JUL 2NS 94 JUlL 2 1945')
PROPAGATION OF ELECTROMAGNETIC PULSES
IN THE IONOSPHERE
by
Pauline Morrow Austin
B.A., Wilson College 1938
M.A., Smith College 1939
SUBMITTED IN PARTIAL FULFILLMENT OF THE
REQUIRElI&ETS FCR THE DEGRETh OF
DOCTOR OF PHILOSOPHY
at the
MASSACHUSETTS INSTITUTE O TECHNOLOGY
1942
Signature Redacted
Signature of Author ...... Department of Physics, October 7, 1942 Signature Redacted Certified by: ...... b71 Thsis Iiperyisor Signature Redacted
Chairman!, Department Committee on Graduate Students MANAGEMENT GUIDELINES FOR THE EVALUATION AND SELECTION OF THE WELDING TECHNOLOGIES FOR USE IN OUTER SPACE by Ravikumar Ramiah Nagabushanam Submitted to the department of OCEAN ENGINEERING in partial fulfillment of the requirements for the degree of Master of Science in Ocean Systems Management
ABSTRACT
Future construction of space structures and inter planetary vehicles will be carried out in space. Also due to the increased service life of the space structures there is an increased need of repair and maintenance work to be carried out in space. NASA has plans for using welding for this purposes. By using welding reliable repair, maintenance and construction of space, structures can be achieved. However, at present research on space welding is at its infancy and not many experiments have been conducted so far. This is mainly due to the resource constraint faced by NASA.
This thesis explains the need for using proper evaluation and selection methods for choosing R&D projects. It also examines the drawbacks involved in using conventional financial techniques and suggests the use of option valuation techniques and decision tree analysis to overcome those drawbacks. In order to overcome the resource constraints the need for developing alternate strategies has been discussed. The benefits of developing space technologies and the opportunities for developing commercial products and processes have been analyzed. The main focus of this thesis is the financial and strategic issues involved in the decision making process for R&D.
Thesis Supervisor: Koichi Masubuchi Title: Professor of Ocean Engineering and Material Science
2 ACKNOWLEDGEMENTS
I wish to express my deepest gratitude to Professor Koichi Masubuchi, who advised and guided me during my stay at MIT as a professor and a friend. He made the necessary financial aid available and always provided a clear view of the big picture. I am forever indebted to his cheerful and kind support.
I would like to thank Professor Henry S. Marcus, my thesis reader. His help was always enthusiastic and direct, and was available despite his busy schedule. I would like to thank my great friend and guru Dr. Vasudevan for everything he has done for me.
I would like to thank Sushi, Kulasekar uncle, Ram, Mani anni, Anand, Gheetha and Ashok for their immense faith and confidence in me. I would like to thank M.E. Devarajan uncle and family for their kindness and love.
My deepest thanks to my parents and wife, Jaya, who have made many sacrifices and have always encouraged me. Saluations to the Great Lord Anjeneya.
3 DEDICATION
DEDICATED
TO THE IMMENSE LOVE AND AFFECTION OF MY FATHER NAGABUSHANAM AND MOTHER RANGANAYAKI KUMARASAMY
AND
TO THE WONDERFUL
MEENA, ASHWIN, SUNDER, DHIVYA AND SEENU
4 TABLE OF CONTENTS
1 Thesis Overview...... 9
2 Background...... 16
2.1 History of Space Research...... 17
2.2 Space Policy...... 23
2.3 Space Program s Under Development...... 25
2.3.1 Space Station Program ...... 25
2.3.2 Other Space Programs...... 31
3 Introduction...... 34
3.1 Fabrication, Maintenance and Repair of Space
Structures...... 35
3.2 Advantages of Using Welding...... 37
3.3 Requirements of the Welding Technologies...... 41
3.4 Welding Methods Considered for Space Welding...... 46
3.4.1 Strengths and Limitations of these Welding
Technologies...... 52
3.4.2 Present Status of Space Welding...... 58
5 3.5 Resource Constraints Faced by NASA...... 63
4 Managing R & D ...... 65
4.1 Risky Nature of the R&D Projects...... 69
4.2 R&D Expenditures Vs Capital Investment Expenditures ... 71
4.3 Need for Proper Evaluation and Selection Methods...... 73
4.3.1 Analysis of Alternatives...... 74
4.4 R&D in the Public Sector...... 78
5 Evaluation Techniques...... 81
5.1 Conventional Financial analysis...... 84
5.1.1 Limitations ...... 86
5.2 Alternate Methods of Evaluation...... 90
5.2.1 Option Pricing Valuation...... 90
5.2.2 Decision Tree analysis...... 95
6 Strategic Planning ...... 102
6.1 Benefits of Strategic Planning...... 103
6.2 Strategies...... 107
6.2.1 International Co-operations...... 107
6.2.2 Commercialisation of the Space...... 110
6 6.2.3 University Research...... 116
7 Benefits of Developing Space Technologies...... 118
7.1 Opportunities for Developing Commercial Products and Processes ...... 126
8 Sum m ary...... 134
9 Reference and Bibliography...... 140
LIST OF FIGURES AND TABLES fig(1): International partners contribution to Space Station [34].... 27 fig(2): Artist's conception of US and Soviet's Space Station [28]...... 28 fig(3): Future Activities in space [28]...... 30 fig(4): Astronauts explore the Moon using a variety of Lunar vehicles [42]...... 32 fig(5): Comparison of welded and riveted structural joints [7]...... 38 fig(6): Welding selection considerations [14]...... 48 fig(7): Survey of space welding publications [24]...... 60 fig(8): Projected benefit and cost stream for projects [32]...... 85 fig(9): Value of a call expiration [33]...... 92
7 fig(10): Basic diagram of a decision analysis [30]...... 96 fig(11): Simple decision tree for product development [30]...... 99
Table(l): Characteristic of the space environment [14]...... 43
Table(2): Welding processes and related issues of concern for space applications [14]...... 49
Table(3): Investments, options and R&D options [36]...... 93
8 chapter 1
THESIS OVERVIEW
9 chapter 1
THESIS OVERVIEW
NASA has plans for an aggressive space exploration program in the next 30 years, which includes a manned space station, lunar base and mission to Mars. The manufacture and assembly of efficient orbital stations and operating platforms directly in space are also planned. These projects require advanced technologies for construction of vehicles and structures that can withstand high gravitational forces, long term exposure to radiation and bombardment by space debris and micrometeorites. In case of repair and maintainance of space structures, in order to achieve a high reliability and ease of repair for a structure that is expected to last 20 or more years, joining by welding is considered by the NASA's space structures designers.
The _1se of welding to assemble large complex structures has many advantages. It will be more economical to launch only structural components, saving the final joining of these sub- structures until they are in the orbit. By performing the final construction in space, structure does not have to be designed to withstand the high stresses which could occur during launch. Moreover, welding does not increase the weight of the structure, offers greater flexibility in the selection of joint designs, and yields gas tight coupling of components.
10 In order to successfully perform welding in space, considerable knowledge is required to select the proper welding processes. Therefore, more studies and experiments on welding technologies suitable for space applications should be systematically carried out. At present welding fabrication on earth has been reasonably well established. This has been achieved mainly through experiments, experiences and analysis. In order to successfully accomplish welding fabrication in space, we must develop a similar technology or know-how for space welding.
A single welding process can do certain welding jobs, but there are many other jobs which cannot be successfully performed or which can be more effectively performed by other processes. No single welding process will be sufficient to perform all the welding tasks in space. Also in view of the trade-offs caused by the complex interaction of environmental effects, human factors, and particular application limitations, it would be prudent to equip the space repair facility with several different welding systems to cover a wide range of possible repair contingencies. Hence systematic research should be carried out for developing space welding fabrication technologies. However, at present, research on space welding is at its infancy and not many experiments have been conducted so far. This is mainly due to resource constraints faced by NASA.
During the past three decades, the National Aeronautics and Space Administration has enjoyed the advantages of having a very clear set of focused objectives over the course of a series of political 11 administration. As the agency has matured and the opportunities for activities in space have expanded, the resources available to the agency for its endeavors have not maintained the pace. It is this resource limitation that has made it necessary for NASA to assess a number of options and evaluate appropriate directions for the future.
The budget process in the case of the NASA budget is in fact a "zero sum" one, and the entire agency shares a fixed amount of dollars. This is a very important issue given that the amount of interesting work far exceeds the amount of money available to challenge it. This leads to competition among the field installations for their "piece of the action." While this need not lead to an adversarial results, it often does lead to imbalances and cutting down R&D activities. Therefore, evaluating and selecting the appropriate projects that will be undertaken is one of the most important tasks for R&D management. The decision making in this case is particularly difficult and complex because of the unavoidable fact that the R&D process is generally unpredictable.
The decision-making criteria for R&D expenditures are an extension of the decision-making criteria for capital investment expenditures. However, there is an important difference between decisions involving investment in R&D, which purchases knowledge, and decisions involving investment in capital, which purchases plants and equipment. The difference is in the greater degree of risk or uncertainty (or both) inherent in R&D decisions.
12 Capital investment is, in essence, present sacrifice for future benefit. Since the present is relatively well known, whereas the future is always unclear, capital investment also involves certain sacrifice for uncertain benefit. Expenditure for R&D can similarly be regarded as certain sacrifice for uncertain benefit. The greater uncertainty associated with R&D expenditure decisions is largely attributable to the fact that a longer projection into the future is required.
Society and technology have become so interwoven that the successful decision must be able to synergize an entire system of human, political, economic, social, ethical, legal, and technical factors. A large element of judgment is required in solving these management problems. But reliance on judgment alone is not sufficient to cope with today's demands. A much more structured, more systematic and more powerful decision making process is needed. One of the basic problems for NASA is measuring the costs and benefits of the R&D projects for each period and transforming them all back to the present so that one measure of value may be obtained. They have a somewhat difficult problem of measuring benefits because they should include the social benefits (and costs) of the project. Government R&D projects are not without risk so the decision maker is faced with the necessity of making a risk analysis.
With large uncertainties of input parameters, R&D projects cannot be evaluated readily with standard financial evaluation procedures which require single-point inputs. In addition, because 13 of the greater range of possible outcomes, R&D projects may present significant strategic implications. Separating the technical, financial and strategic evaluations of a R&D project is much more difficult than for a project of similar magnitude with no significant uncertainties. The need to integrate the various functional evaluations has important implications to the decision-making process.
Therefore, from both a financial and strategic perspective, evaluating desirability of the R&D projects is uniquely complicated. Since in R&D projects uncertainty of outcomes is a major consideration in the investment decision-making process. Traditional discounted cash flow (DCF) financial evaluation techniques have been criticized as inherently biased against R&D projects. Some critics claim that an overemphasis on short term returns by many American companies, resulting in diminished competitiveness of American firms, can be traced to over-reliance on DCF techniques in the investment decision-making process. Alternate financial evaluation techniques have been developed to substitute for or combine with DCF techniques in an attempt to better deal with the uncertainties of outcomes presented by R&D projects. Examples of alternate evaluation techniques are option valuation techniques and decision-tree analysis [18,43].
In this thesis, management guidelines for the evaluation and selection of the welding technologies suitable for space applications have been discussed. The main focus of this thesis is the financial and strategic issues involved in the decision making process. Also 14 the implications of riskiness for financial evaluation techniques and decision making processes are addressed. International co-operation in R&D efforts, alternate form of funding, commercialisation of the space activities have been analyzed as alternate strategies. Finally, the benefits of developing space technologies and the opportunities for developing commercial products and processes have been analyzed.
15 chapter 2
BACKGROUND
16 chapter 2
BACKGROUND
2.1 History of space research
The catalyst for a major space programme in the United States was Sputnik. The political repercussions of the Soviet breakthrough in space in 1957 brought forth Congressional demands for an across- the-board revitalization of US scientific and technological development, including programmes to improve science and engineering education, increase federal support for science and attract more people to technical careers.
Sputnik also stimulated the formation of a national space agency. President Eisenhower signed the National Aeronautics and Space Act of 1958 which established the National Aeronautics and Space Administration (NASA). The President also established the post of White House Science Advisor and the President's Science Advisory Committee (PSAC).
NASA was deliberately designed to be a civilian agency directly responsive to the President and responsible for all civilian space- related research and de.velopment (R&D). From the beginning, a separation was made between civilian and military space R&D, with military space R&D to be conducted by the Department of Defense (DOD). The Act intended that NASA's 'activities in space should be devoted to peaceful purposes for the benefit of mankind' and should be open to the public. 17 The first space activities involved development of launch vehicles for carrying satellite payloads for science and communications. The large number of launchpad disasters among the early satellites testified to the ambitious pace and objectives of the agency. NASA's earliest launches include the Tiros series of R&D and meteorological satellites which began in 1959. Communications satellite launches were initiated in 1960 with the Echo, Relay, Syncom and, in the 1970s, the ATS satellites. The Explorer series of astrophysical and observational satellites began in 1961.
NASA undertook its most famous planetary satellite series, Pioneer, Mariner, Viking and Voyager, in 1962. That year Mariner 2 passed by Venus, investigating the atmosphere and planetary temperatures, marking the first successful planetary exploration. Later Mariner flights explored Mars and returned to Venus. US exploration of the moon began in the early 1960s with the Pioneer satellites, followed by an Explorer satellite investigating the space environment around the moon. The Apollo space missions also greatly expanded lunar research by retrieving large rock and soil samples.
The first commercial communications satellites, Intelsat and the Westar series, were launched by NASA in 1962. The Explorer, PAGEOS, GEOS and LAGEOS geodesical satellite launches started in 1964. NASA initiated NOAA's meteorological data collection satellites, the ITOS, GOES and NOAA series in 1966. The Landsat
18 series of remote sensing satellites began in 1972. Seasat, the oceanography satellite, was launched in 1978.
President Kennedy's announcement of the Apollo programme, with the objective of landing humans on the moon by the end of the 1960s, marked the beginning of an enormously challenging and costly technological feat that profoundly shaped the US space programme and the course of space research in the 1960s. The commitment to space science encompassed by the Apollo programme was so large that most other space activities also benefited. In the process of achieving the Apollo landing, NASA added significantly to its laboratory structure, creating a combined government contractor workforce -that exceeded 400,000 people at its peak.
Post-Apollo planning for NASA began in- the mid-1960s. However, many of the agency's most ambitious proposals for continued lunar exploration, development of a space station and human planetary flight were rejected by the Johnson Administration. In general, the expansionist attitude toward space ventures was shifting to a more conservative, cost-conscious approach. Proposed missions with significant costs would be funded only if it showed clear utilitarian, including economic, benefits. Apollo technology was used in subsequent visits to the moon and in Skylab. Skylab stretched the utility of Apollo technology, demonstrated extended human flight in Earth orbit and made possible a number of research operations, including observations with a solar telescope.
19 A1
In 1971 NASA began exploratory design of the shuttle. A firm commitment was made to proceed with the shuttle in January 1972. The shuttle was intended to serve a wide variety of 'national needs, both civilian and military. The European Space Agency (ESA), a consortium of European nations, constructed Spacelab, a laboratory module, as a shuttle payload.
The development of the shuttle had two primary effects on US space research and the overall space programme. With the shuttle it was now possible to carry larger, more complex payloads into space, which would then be boosted into higher orbits. The shuttle changed the constraints of these payloads by enabling them to be designed for reuse and repair and for human tending prior to launch into orbit. Larger crews consisting non-astronaut scientific specialists would be able to conduct complete scientific operations in space.
During the Reagan Administration, NASA had continued to emphasize Uevelopment and operation of the space shuttle. However, early in the 1980s many planetary and space science programmes were cancelled or deferred, the space applications technology transfer programme was eliminated altogether and the technology utilization programme was sharply reduced. The budget reductions reflected the Administration's fiscal concerns and its commitment to limit and define more narrowly the role of government support in space R&D.
Development of the shuttle resulted in a five-year hiatus in manned flight missions. The substantial cost overruns of the 20 shuttle's development had also increased budget pressure on other new and existing NASA programmes, such as space science and applications. With development of the shuttle completed, NASA is now involved in serious design and definition of the space station. The new multibillion dollar programme in a period of severe fiscal restraint has caused some concern within the agency and within the scientific community.
Development and funding of a large scale project such as the Space Station generally occurs separately from other space science programmes, but the schedule delays and cost increases has put pressure on the space science components of NASA's budget. However, the concerns about present commitment to large future costs have been allayed somewhat by the modular approach to the Space Station, which provides flexibility in scope and scheduling. Since the shuttle's development has ended and customer reimbursements for shuttle operations has begun to flow in, the Administration has announced commitment to a 1 per cent per year real growth in the total NASA budget, which will allow much larger growth in NASA R&D.
The Space Station does not fit within NASA's overall space programme as a specific project with clearly defined objectives; rather it is an important infrastructural precursor to sustained human activity in space. The combination of the shuttle, the Space Station and related technologies should also significantly enhance US space research capabilities in the 1990s. Combined with generally reduced funding, the shift toward more permanent and longer-lived 21 A
observatories has led to a dramatic decrease in the number of launches of scientific missions, from an average of six per year in the late 1960s to 1.5 per year in the 1980s.
Nevertheless, President Bush has challenged NASA to work towards one of humanity's most exalted long-range goals, the creation of a self sufficient civilization "living off the land" on Mars. The main benefit is that Mars alone will double the land area available to humanity. This great high-technology endeavour will attract international partners, encourage world peace, stimulate advances in science and engineering, generate broad economic benefits, inspire young people, and give our descendants a magnificent legacy of expanding horizons.
22 2.2 National space policy
In his 1984 address, President Reagan synopsized the vision of mankind's future in space in the 21st century in a very few words. He saw man living and working in space for peaceful, economic and scientific gains. By the turn of the century, there will be a significant increase in the number of humans present in space with a much larger range of operating domains, low earth orbit (both polar and equatorial), geosynchronous orbit and transferring between the two locations. Access to space will become routine with a reduction in cost by a factor of ten from the present expenditures. There will be a wide variety of platforms and facilities in orbit for both science and commerce. Some will be automated, some man tended and still others permanently manned. Man will begin to look to near earth space for resources, and developing completely closed ecological systems in space. Pilot processes will be underway to prove the viability of high technology manufacturing in space.
The NASA Goals articulated in 1984 as a direct response to the vision statement are:
1) Develop within a decade a permanently manned Space Station;
2) Conduct effective and productive space and earth sciences programs;
3) Conduct effective and productive space applications and technology programs;
23 4) Make the Space Transportation System fully operational and cost effective in providing routine access to space;
When Americans moved westward in the nineteenth century the government provided land to settlers, incentives for building railroads, and military protection. In modern terms, the government provided or encouraged the development of an infrastructure to allow the westward expansion of the country. Development of air transportation also required a government sponsored infrastructure consisting of airports, flight control centers, radar sites, weather stations, and communications systems. Now once again the United States is developing an infrastructure for expansion into the new frontier of space. A transportation system and a permanently manned space station are the first steps.
Fuller development of the scientific potential of the shuttle and Space Station will bring about the systematic merging of the unmanned science programme and the manned space programme. The Space Station will provide for in-orbit assembly and repair of spacecraft and experiments, a laboratory for conducting experiments, and a base for space missions, further reducing the number of mission launches and, ideally, the cost of experiments.
24 2.3 Space programs under development
2.3.1 Space Station Program
In his State of the Union Message of January 5, 1984, President Reagan directed NASA to develop a permanently manned Space Station and to do it within a decade. The purpose is for peaceful economic and scientific gain and for quantum leaps in research and technology.
The Space Station is expected to be completed by mid 1990's. According to the current design the space station will be larger than a football ground when completed. The structure consists of a long horizontal truss 50 feet across. Four modules will be attached to the truss: two United States modules, one of which -will be used as a laboratory where microgravity experiments will be conducted, and the other used as the living quarters for the eight-person crew, containing bunks, a galley, head, shower, washing machine, medical facilities and excercise equipment. The European Space Agency is planning to provide an attached laboratory. The Japanese module will have a platform outside the module with robotic arms to conduct space experiments.
Four large nodes, or tunnels, will connect the modules. The nodes will serve primarily as passageways for crew and equipment, but will also house many of the systems required to operate the station. The atmosphere inside the modules and the tunnels will be the same as that of Earth's surface. Canada having produced the
25 Canadarm of the space shuttle will develop a mobile servicing arm for the Space Station, along with an arm to be used in assembly of the station. Large solar panel arrays will provide electric power for the station and other panels will radiate accumulated heat into space. The truss structure will also accommodate a variety of instruments for observations and experiments fig(i) and fig(2).
The Space Station is the culmination of a trend toward sustained observations from larger, more complex, longer-lived observatories and planetary explorers. The space telescope is an example of permanent remote sensing observatories. An Earth Observing System (EOS) now under consideration for the space station's polar platforms will provide sustained simultaneous observations necessary to understand Earth's physical, chemical and biochemical systems.
Many of the scientific research tasks now being done by satellites will be done better aboard a permanently manned Space Station. We will see advances in astronomy, earth resources, and solar and space physics from the laboratory in space. Cost savings are a factor, too. Presently, unmanned satellites must be proven 100 percent perfect before launches because if something goes wrong in orbit, that is the end of it. Ground testing to certify the equipment ready for space is expensive and time consuming. Such perfection is not so necessary if the equipment is aboard a space station with someone tending it. Also, now if the results of experiments and measurements suggest a new or modified approach to the experiment, a new satellite has to be designed, tested, and launched. 26 ESA JAPAN NASA/GO DDARD ELEMENTS: ELEMENTS: (Maryland) " PRESSURIZED * PRESSURIZED LABORATORY LABORATORY MODULE ELEMENT5- MODULE S EXPOSED FACILITY 0 POLAR PLATF Gnu * POLAR PLATFORM * EXPERIMENT LOGISTICS - ATTACHED P AYLOAD "MANNED-JENDED MODULE - CLCOM TI FREE FLYER C SERVICER (UTFI) -
NASA/ , ' JOHNSON
E~fTS: * TRUSS * MOBILE TRANSPORTER (PHASE 1 CANADA -4 NASA/MARSH ALL * AIRLOCKS ELEMENTS: (Alabama) * NODES (PREsSUn SHELL - MSFCl 0 MOBILE SERVICING SYSTEMS: CENTER (PHASE 11 ELEMENTS: * EXTERNAL THERMAL CONTROL * PRESSURE $HELLS 0 EVA FOR NODES * DATA MANAGEMENT * LABORATORY MODU tL 0 COMMUNICATIONS & TRACKING * HABITATION MOU L9 * GUIDANCE. NAVIGATION S CONTROL ASAILEWIS (o (OUTFITTING TD V JSC( 0 PROPULSION (tHRUSTER TO BY MSFCA o) * LOGISTICS MODULI 1PRESS a UNPRESSI * NSTSSBS ATTACHMENT SYSTEMS ELEMENTS: SYSTEMS: * POWER MODULES - PV * EC~LS 5I1tEM: * INTERNAL THERMA L CONTROL * ELECTRICAL POwER * INTERNAL AUDIO & VIDEO DISIRIBUTION
fig(l): International partners contribution to Space Station 1341. fig(2): Artist's conception of US and Soviet's Space Station [281.
U.S. SPACE STATION
134'
SOVIET MIR
SOS- In the future, people tending experiments on or near the Space Station can modify the experiment and test, repair, or replace the equipment. Radio, television, and data link interactions between the on-board scientist and the scientists on Earth can be fruitful in many ways. Experiments and manufacturing aboard a space station could go on indefinitely.
In advanced robotics, any move of the operator's hands and arms would be reproduced exactly by the machine. Therefore, by using advanced robotics arm an astronaut in a Space Station could take care of repair, maintenance or adjustments. Using orbital- maneuvering vehicles (OMV), satellites and perhaps people will be carried to and from higher orbit, particularly geosynchronous orbit. The OMV will be able to return satellites to the Space Station when necessary for repair and maintenance. It, too, -would be remotely controlled from the Space Station.
An *OMV could boost the space telescope to higher orbits as needed to maintain pointing accuracy. If it transported the telescope to an orbit higher than can be reached by the Shuttle, boosts would not be required as often. An OMV could also bring the telescope back to the station for routine maintenance and overhaul. Doing these jobs in a "drydock" at the station would save the expense and possible damage to the instrument inherent in bringing it back to Earth.
29 PROGRAM PLANNING FOCUS
SYSTEM MISSION CLASSES CLASSES 1990's 2000's 201O's 2020's
ADV. CilYO - EO OTV 01 I hASLUNARI AND MARS 0 VM DAV.MNE 1V RnANSPOr IAlION SYSI EM C) CREW EMERGENCY RESCUE VEHICLE@ 0 2 SDV o NIITILEIIEElACEMEN
PIANE IAfY SYSl EI M ADV. LAUNCH SYStEM __LANEAY__Y___ _E _ MOBILE COMM. SA
cc----- COM RENDEZVOUS/ASIEROID FLY Y U SAIiIIN OIIDIIER S. 4 MARS SAMPLE RETURN PLANEJARY Q PlIOUES
LEAII OBSERVING SYS IEMS GLO OUIEn PLAN tr OIIIBIIEIIS
LARGE DEPLOYABLE REFLECTOR IOC SPACE STATION GROWIH SPACE SI IO0 U).Tt WOW ETHEIIEDSYSTEMS
IL U) LUNAIIOUIPOSI LUNAR BASE _J U) >.MAIIS U) MAIlS SPIllNIS AIlPOSI * *
fig(3): Future Activities in space 1281. 2.3.2 Other space programs
In the summer of 1989, at the twentieth anniversary celebration of the Apollo's landing on moon, the U.S. President George Bush announced his plan to construct a base on the moon and to send a manned-mission to explore the planet Mars. As its first action, NASA presented a plan which includes the re-landing and construction of a permanent base on the moon, by 2001; furthermore, in 2011, NASA will send human explorers to Mars, who will build permanent base on Mars fig(3).
According to the plan, in the year 1999, an unmanned spaceship will be sent to the moon, followed by a four-man crew sent to the satellite for thirty days in 2001 and a one-year exploration of the moon by mid-2002; moreover, by 2003, a.nuclear power device and an electricity manufacturing instrument will be established; in the year 2005, a residence module will be constructed, enabling eight men, who alternate shifts every year, to live on the moon starting the following year. In addition, the nuclear power generating ability will produce upto 550 kilowatt, while the oxygen production will rise to 60 tons per year. On the Mars, a four-manned spaceship will reach the planet in 2011, performing investigation in a radius of ten kilometers for thirty days. Moreover, building construction materials for permanent residences will be transported along with four men, who are planned to stay on the planet for 600 days fig(4). Following the year 2018, standard consumption goods, various parts of scientific equipments, etc., will be transported to further continue the 31 fig(4): Astronauts explore the Moon using a variety of Lunar vehicles [42].
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32 exploration. Therefore, it is very clear that due to these increased activities in space there is an immediate need for developing advanced technologies to support the various space programs. Space Welding is one such technology. In the next chapter the advantages and the needs for using welding for fabrication, maintenance and repair of space structures have been discussed.
33 -j
chapter 3
INTRODUCTION
34 chapter 3
INTRODUCTION
3.1 Fabrication, maintainance and repair of space structures
During the thirty year service life, the Space Station will require repair. The damage may be caused by collision with the space shuttle during a docking approach, accidental impact with another man made object, collision with debris in space or collision with a meteorite. It is possible that some of the experiments to be carried out at the Station may cause damage as well. Components of the Station may have to be replaced as routine maintenance, perhaps such as a solar power array. New equipment may be required for further experiments, but for which no foundations or brackets are on the Station. The space shuttle may also, at some point, require repair during a mission. It has also been estimated that the Space Station will require 2,200 hours of astronaut conducted maintenance annually.
As already been indicated, due to their large size future construction of inter planetary vehicles and space structures will be carried out in space. Several shuttle flights will bring in materials for vehicle construction to the Space Station where construction will proceed. The final launching of a large space constructed vehicle will be much easier in space because the bulk of the gravitational force of earth does not have to be overcome during a space-launch. Because the thrust required for a space launch is greatly reduced, the
35 structure of the vehicle may not have to be as massive to tolerate the high stresses developed in a terrestrially launched vehicle.
In order to carry out reliable fabrication, maintenance and repair of these space structures elaborate welding techniques are required. The repair of damaged structures containing human life becomes significantly more critical in space applications. Therefore, a short repair time is very important. Hence it is necessary to maximise the versatality of the joining processes to be developed for space applications.
36 3.2 Advantages of using welding
A weld can be defined as a coalescence of metals produced by heating to a suitable temperature with or without the application of pressure and with or without the use of the filler metal. Welding is the most efficient way to join metals. It is the only way to join two or more pieces of metal to make them act as one piece. It is widely used to manufacture or repair all products made of metal. Almost everything made of metal is welded; the world's tallest building, moon rocket engines, nuclear reactors, home appliances, and automobiles to mention a few.
To join two members by bolting or riveting requires holes in the parts to accommodate the bolts or rivets. These holes reduce the cross-sectional area of the members to be joined. The joint may also require the use of one or two gusset plates, thus increasing the weight of material required. Whereas, the entire cross section of a member of a welded design is utilized to carry the load. In view of this material savings, ships and storage tanks are no longer riveted. Pipes joined by welding offer similar economies. However, the wall thickness of the pipe should be heavy enough to carry the required load.
According to the present plans space station is to be fabricated on earth and assembled in space using mechanical fasteners. Mechanical fastening is simple, however, welding has the following advantages when compared with mechanical fastening fig(5):
37 Pipe jointsi
II
0 00 000O
RIVETE SPLUCE IN WIDE =LANGE MEM.BER
WELDED SPLICE IN WIDE FLANGE MEMBER fig(5): Comparison of welded and riveted structural joints f7].
38 (a) Welding has high rigidity. Therefore, it is easy to maintain their exact shapes.
(b) Mechanical joints may become loose during service.
(c) It is difficult to obtain air tightness with mechanical joints during service.
(d) Welded joints normally have higher strengths over a wide range of temperatures than mechanical joints.
The advantages of using welding over casting are as follows: Converting castings to weldments allows the designer to reduce weight by reducing metal thickness. Welding is a design concept which allows freedom and flexibility not possible with cast construction. Heavy plates can be used where strength is required and thin ones can be used where possible. The uniform thickness rule and minimum thickness required for foundry practice are not necessary .for weldments. Additionally, high-strength materials can be used in specific areas, while normal strength materials are used where required.
Additionally, welding is the best way to protect and conserve materials by protecting their surface with special metal overlays. Corrosion and wear can be greatly reduced by welding. Special alloys are weld-deposited on base metals to provide corrosion- resistant surfaces. Hard surfacing overlays can be made by welding to provide special alloys with wear-resistant surfaces.
39 All metals can be joined by one welding process or another. There is a saying, "If it's metal, weld it," and it is certainly true. The weldment design can be readily and economically modified to meet changing product requirements. The production time for a weldment is usually less than that of other manufacturing methods. The weldment will be more accurate with respect to dimensional tolerances. Weldments are more easily machined. The capital investment for producing weldments is quite low.
As mentioned already, most construction jobs in the early stages of the Space Station Program will be performed on earth, and fabricated modules will be joined, by mechanical fastening methods such as bolts and nuts. Although most bolts will be placed on earth, we may find it necessary to place some bolts on site in space. Or we may find that some joints are mismatched, requiring some bolts to be cut and new bolts placed in different locations. Also, there will be many occasions in which insulation materials will need to be placed over some structural members. By using stud welding it is possible to place studs without piercing holes through the structural members; then these studs can be used to secure the insulation materials. As already indicated, structural members may be damaged during service. For example, a hole may be pierced in a wall of a space station when it is hit by a meteorite or other space debris. It is possible to develop welding techniques for repairing some of the damages on site, for example by placing a patch over the damaged areas.
40 3.3 Requirements of the welding technologies
Welding is a relatively complicated joining process, which requires certain scientific knowledge and human skills. Proper processes, equipment, and consumables, as well as joint design and welding conditions (welding current, arc voltage, torch travel speed, etc.) must be used to successfully weld certain materials in given thicknesses. Welding operations, including manipulation of the welding torch, must be performed in a proper manner in order to produce a weld free from defects such as cracks, lack of fusion, porosity, and slag inclusion. Welding engineers have spent considerable effort to -minimize the adverse effects caused by oxygen, nitrogen, and hydrogen.
Welding in space creates greater challenges and opportunities for welding engineers. Many of the commercially available processes may be used for space applications. However, in space applications we must consider many different materials, different structures and different welding conditions. The lack of an atmosphere in space will be helpful in obtaining uncontaminated welds and also will readily permit the use of high power-density welding processes such as electron beam welding. However, a number of problems will be posed by the particular nature of the space environment and the great distance from the earth. In order to successfully perform welding construction and repair in space, we must first study problems associated with welding in space and then develop welding technologies suitable for space applications.
41 A
Space is characterized in particular by four conditions table(1): a) Weightlessness: This suppresses static buoyancy(lift) convection and a range of other physical effects. It also affects for example the density of materials and their phases. The weightlessness plays an important role as regards the surface tension of liquids. Also the astronauts cannot propel themselves up during their work, as is usual when working under terrestrial conditions, which of course considerably complicates assembly and welding work. On earth, gravity and surface tension slightly compress a weld pool to squeeze some of the gases out of the weld. In space, where gravity is greatly reduced, the effect of gravity will be greatly reduced, though surface tension of the weld metal will still be effective in forcing out some gases. These effects require more study.
b) Vacuum: It may be assumed that the large volume space stations
are erected on an orbit corresponding to a pressure of 10-2 to 10-4 Pa. This is the pressure range existing in electron beam and diffusion welding. The space vacuum is characterized, however, by an extremely high, almost infinite pumping rate. The work must be carried out in space suits, which gives rise to further difficulty. The high vacuum of space may cause some gases that remain in solution in the molten weld metal on Earth to form bubbles in space which may cause porosity in welds. Techniques will have to be developed that will minimize this effect. c) Temperatures: The boundary between the illuminated and shaded areas is fairly sharp. This means that the structures are exposed to
42 Table(1): Characteistics of the space environment[14].
Alitude Pr Kinetic Gasnoas Compotion Ultraviolet Partcle radiaton (kM) (torr) temperare density radiation (OK) (particle (paricles CM-3) -21 9 Sea level 760 -300 2.xl01 78% N2, Section of 21% 02, solar 1%A spectrum .. , 0.3
17 30 10 -1200 4x10 N2 ,02 ,A Absorption
__ _ _zone_
200 10-6 -1300 1010 N2 ,0.02,0+ Full solar sMectm
800 10-9 106 O.He.o+,H Full solar
I_ _ spectrum 6500 10-13 103 H+,H.He+ Full solar 104 pirtons spectrum >35 MeV 104 electvns >40 keV
13 protons 22000 <10- 101-102 85% H+, Full solar 108 15% He2+ spectrum >5 MeV 108 electmns >40 keV 104 electrons >1.6 MeV
43 temperatures of between about -120 and +220 OC in operation. The decreased thermal and material exchange in space also means that regions of large temperature difference can exist close to one another on a structural part. The expected temperature ranges on the skin of the Space Station are +250 OF to -250 OF depending on whether the surface is in the sun or the shade. With such a wide variety of temperatures, coupled with the high thermal conductivity of aluminum, control of the cooling rate of any weld is difficult to impossible without a great deal of energy input, of which the Space Station is in limited supply. The wide range of cooling rates expected in space welded materials may require different techniques depending on the temperature of the base metal to minimize the effects of the wide-ranging cooling rates.
d) Ionizing and hard ultraviolet radiation: Over- a prolonged reaction time these impair the properties of materials and their weld joints.
Hence we must develop the welding technologies that are suitable for these space conditions mentioned above. Also, the space station will have a limited source of continuous power which must serve all of the purposes of the station. Dedicated power for welding is not an option at this point. Therefore, any type of joining used must minimize the power required in its adaptation to operation in space. The restrictions of any payload for launch to, or contaminent on the space station apply also to the types of welding equipment used in orbit. The chosen methods must minimize weight and volume in order to be feasible. All joining equipment must be able to operate under the microgravity, high vacuum and extreme
44 temperature ranges conditions as well as the joints they produce must be acceptable and inspectable. Exterior joining techniques must also limit the amount of material and electromagnetic contamination they produce to reduce harmful effects on the body and operation of the station. Joining within the habitat of the module must be safe for human exposure, so toxic products, oxygen depleting reactions and dangerous electrical and mechanical energy releases must be minimized.
It should also be noted that even though the welding of simple joints in a certain material is successfully made, it does not necessarily mean that welding fabrication of a complex structure would be successfully achieved. There are certain problems associated with welding fabrication of complex structures composed with a number of members. One of the problems is related to residual stresses and distortion. Hence research should be carried out to understand the influence of residual stress and distortion on welding in space. Finally, it should be noted that welding is only a part of total fabrication system that includes plate cutting, forming, and edge preparation, assembly of parts to be welded and tack welding, welding, and inspection. In considering welding in space, we must also consider how to perform total fabrication in space.
45 3.4 Welding methods considered for space welding
Today about 100 or so welding processes are known. However, over the past twenty five years serious studies have been carried out in around fourteen welding processes for use in space. They can be classified into three major groups as follows:
ARC WELDING GROUP
1) Gas Tungsten Arc Welding (GTAW)
2) Gas Metal Arc Welding (GMAW)
3) Plasma Arc Welding (PAW)
4) Stud Welding (SW)
MISCELLANEOUS GROUP
5) Electron-beam Welding (EBW)
6) Laser Welding (LBW)
7) Resistance Welding (RW)
8) Brazing (B)
9) Focussed sunlight technique (FST)
10) Friction welding (FW)
SOLID-STATE GROUP
11) Ultrasonic Welding (USW)
46 12) Diffusion Welding (DFW)
13) Explosion Welding (EXW)
14) Cold Welding (CW)
Brief description of these welding methods are as follows, Arc welding: Shielded metal arc welding accounts for the largest total volume of welding today. In this process an electric arc is struck between the metallic electrode and the workpiece. Tiny globules of molten metal are transferred from the metal electrode to the weld joint. Arc welding can be done with either alternating or direct current. A holder or clamping device with an insulated handle is used to conduct the welding current to the electrode. A return circuit to the power source is made by means of a clamp to the workpiece. Gas-shielded arc welding in which the arc is shielded from the air by an inert gas such as argon or helium, can deposit more material at a higher efficiency and can be readily automated. The tungsten electrode version finds its major application in highly alloyed sheet materials. Either direct or alternating current is used and filler metal is added either hot or cold into the arc.
Friction welding: Friction welding is a process in which the heat for welding is produced by 'direct conversion of mechanical energy to thermal energy at the interface of the work pieces without the application of electrical energy or heat from other sources to the workpieces. Friction welds are made by holding a nonrotating workpiece in contact with a rotating workpiece under constant or
47 MA F AC I ( IRS
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-I 4P lb APPLICAYIDN .Am- L -
vAC JINT GEWI RY ErrI cis MAT1IM 1A TMIAL PRPER TIES T T REMTE crHi RIEI D VS LOCAL OPIJRA MI IDIWERATURE DITERIR VS EXTERIOR REPAR
fig(6): Welding selection cousiderationsil41. EVIRNMENTALFACTURS Table(2): Welding processes and related issues of concern for space applications[14]
PROCESS
I I PRC
Issue Brazing Remsance Lamer Eecron GTAW welding welding beam
weldin _ IVA Possible Possible Possible No Yes EVA Possible Possible Possible Yes Yes Quality Medium Medium HMzb Hi__ Hizb Efficienc_ LOw Medium Very low Very hih Hzb Versatility Limited Medium Moderate Limited to Very bigh EVA
Automation Possible Limited Generally Generally Possible Radiation None None None Personnel None (penetrating) shielding for X-ray Radianon None None Eye No Eye (optical) protection protection rea'd =e'd
anspectability Poor Poor Component Component Component devendent devendent deoendent
Other Demonstrated Fit-up advantages on orbit tolerant Process conrol oossible Other Two-side Manipulation Vacuum Inert gas disadvantages access req'd Limited req'd required Fit-up Magnetic 9 deflection 49 gradually increasing pressure until the interface reaches welding temperature, and then stopping rotation to complete the weld.
Resistance welding: Resistance welding is a process in which the required heat for joining is generated at the interface by the electrical resistance of the joint. Welds are made in a relatively short time using a low voltage, high current power source with force applied to the joint through two electrodes, one on each side.
Electron-beam welding: Electron-beam welding is a process in which the workpiece is bombarded with a dense stream of high-velocity electrons. The energy of these electron is converted to heat upon impact. A beam-focussing device is included, and the workpiece is usually placed in an evacuated chamber to allow uninterrupted electron travel. Heating is so intense that the beam almost instantaneously vaporizes a hole through the joint.
Cold welding: The joining of materials without the use of heat can be accomplished simply by pressing them together. Surfaces have to be well prepared, and pressure sufficient to produce 35-90 percent deformation at the joint is necessary, depending upon the material.
Brazing: Brazing, is one of the oldest forms of metal joining used. The brazing joint has relaltively large area and small thickness. The filler metal is either preplaced or fed into the joint as the parts are heated. Parts with small clearances allow the filler metal to flow into the joint by capillary action.
50 Laser welding: Laser welding is accomplished by focussing the light energy emitted from a laser source upon a workpiece to fuse materials together. One of the difficulties is that the speed and the thickness that can be welded are not so much controlled by power but by the thermal conductivity of the metals and by the avoidance of metal vaporization at the surface.
Diffusion bonding: This type of bonding relies on the effect of applied pressure at an elevated temperature for an appreciable period of time. Generally, the pressure applied must be less than that necessary to cause 5% deformation so that the process can be applied to finished machine parts. The process has been used for joining materials and shapes that otherwise could not be made.
Ultrasonic welding: Ultrasonic joining is achieved by clamping the two pieces to be welded between anvil and a vibrating probe or sonotrode. The vibration, properly applied, raises the temperature at the interface and produces the weld.
Explosive Welding: The majority of explosive welding technology has been in the joining of flat plates explosive materials are placed on the opposite sides of plates to be joined and upon detonation, the resulting plastic deformation produces metallic bonding.
Stud welding: The welding of a small diameter stud to some surface, may be accomplished by two different techniques. On both cases, stud welding is a process that is an intermediate step in fabrication,
51 the studs providing anchor points for other parts that are then joined together using mechanical fasteners.
Focused Sunlight joining: In this technique, transducers or mirrors are used to focus sunlight on the area to be welded. The availability of solar energy in space make this technique attractive, but would probably require elaborate sun-tracking apparatus, would be available only part of the time.
3.4.1 Advantages and limitations of these welding processes
Serious studies in case of friction welding for space applications has not been carried out extensively with the exception of welding group of ocean engineering department at MIT. The appealing features of friction welding are as follows, friction welding can be used in attaching studs, bolts, tubes etc. as long as at least one work piece is flat in the region of the joint. Flat plate butt welds and lap joints among others are, unfortunately, not producible by this method. Friction welding is easily automated, requires low operator skill level and low power, produces no harmful by products and shows no detrimental effects in high vacuum or microgravity. For a given material combination, weld quality is highly repeatable since it is determined by the energy of the system which is preset. The discussion of the advantages and disadvantages mentioned in the literature for the remaining welding methods mentioned above are as follows,
Arc welding, is today perhaps the most widely used metals joining method, was one of the first to be tested in actual space
52 conditions during the flight of the Soyuz-6 spacecraft. The Soviets found that the high vacuum of space adversely affected arc ignition and stability in plasma arc welding. Similar arc instability problems were confirmed by the Astroarc Company ( Sun Valley, CA) who was subcontracted to test gas tungsten arc welding under laboratory vacuum conditions [11,14,24,25].
Of the second group of welding processes, electron-beam is perhaps the most promising. Ideally suited for the vacuum of space, actual experiments aboard Soyuz and the 1973 Skylab mission have shown that this method produced superior welds, although some increased porosity was noted in aluminum specimens. Even though it is possible to electron-beam weld in air (which requires more energy input), laser welding has the advantage of negligible beam attenuation under this condition; a possible requirement when welding inside a pressurized module. Even though successful pulsed- laser welding of aluminum has been demonstrated, the major disadvantages of this method are low electrical to optical energy conversion efficiency and significant laser reflection from smooth metallic surfaces both of which result in a lower energy transfer to the workpiece and a consequent need for higher power input. It should be noted that a major prerequisite of any space welding system is low power consumption, since the power availability initially expected on the Station will be limited to 75kW or may be even lower[14,24,25].
Of the four solid-state methods listed, diffusion and explosion welding can be performed in vacuum and is, in fact, a requirement
53 for the diffusion process. Welding under vacuum conditions for ultrasonic and cold welding should not be detrimental to these processes due to its cleanliness preservation effect [14,24].
The cleanliness of a welding method is of the utmost importance in a space environment. It is likely that some amount of welding repair or fabrication will be necessary as the need arises inside the Station as well. Of the three welding groups listed above, the arc processes are the most serious contamination offenders due to their production of fumes and use of gases that could easily pollute such an environment.
Since electron-beam and laser welding vaporize some of the base metal in the process, some fume production is inevitable. Shielding from X-rays high voltages, and welding debris, produced from the electron-beam process are limitations that must be accounted for in equipment design. Laser systems, on the other hand, have two advantages: 1) no potentially harmful X-rays are produced and 2) beam attenuation in air is relatively negligible. However, fume and ozone production are still serious drawbacks. With the exception of explosive welding, which requires relatively large volume of gaseous by-products to achieve a weld, the solid- state methods appear to be the cleanest of the welding processes. This is due primarily to the fact that they depend upon diffusion and/or material deformation to weld in temperature ranges below the melting temperature of the joined materials. This results in negligible fume production [14,24,25]
54 The Soyuz-6 findings indicate that the gas metal arc process produced more pronounced welding beads of decreased penetration due to the dominant surface tension effects. It would seem reasonable to expect similar results in other fusion welding processes. Microgravity should have no effect on solid-state systems since no liquid phases are present. Solid-state techniques consequently eliminate concern over the influence of weld cast structures on joint strength as is the case in fusion welds [14,24].
The expected temperature extremes of 250 OF, coupled with the microgravity and vacuum levels expected on-orbit, will least affect diffusion welding, cold welding, and resistance welding. The adhesion effects between metals in vacuum attributes the apparent increase in adhesion efficiency with temperature rise to the "thermal relaxation of the yield strength and a corresponding increase in plastic ductility." It appears that solid-state bonding methods would benefit from the sun and "hot" surfaces, while fusion welding processes would be better performed in the colder shadows. Since the effects of temperature on welding can be complex and sensitive to the method employed, further study is warranted for each particular repair scenario expected.
The great cost of -space logistics, especially for the support of personnel, underlines the importance of developing automatic space welding for remote locations. To decide on the degree of required or attainable automation and autonomy in space welding applications, we should both consider the requirements of the task on hand, the
55 availability of human operators on site, and the current or projected state of the art in the field. The availability of human operator capable of performing high quality of welding depends on the specific application, but most probably cannot be guaranteed in space construction or repair. Therefore, until the manning level grows large enough to accomodate personnel devoted to the sole purpose of maintenance, repairs will have to be done by scientists and flight crew with minimal joining and repair training. Obviously then, welding systems that are selected and developed for use in space should, be simple to operate and 'Intelligent' requiring minimal welding expertise and control by the operator during the welding process, be as self-contained and compact as possible, be "user friendly" in design (i.e., operable by personnel in a bulky spacesuit, gloves, remote manipulators, etc.), be reliable in producing consistently high quality welds which would minimize extensive re- work by the operator, thereby reducing the need for extensive non destructive evaluation, also, the process must not produce by- products that are harmful in any way.
Therefore it is clear that efforts to develop space welding technology, which do not require the on site presence of the welding engineer is a necessity. It should also consist of welding systems which can perform remote manipulation and which can be used effectively by operators with no welding knowledge. Finally, technologies for performing certain welding jobs through the guidance and assistance from the earth station shall be developed. Although development of a totally autonomous system is currently
56 not feasible, the very active research in artificial intelligence and related field can most likely guarantee that such a development will soon be possible.
Also in remote fabrication good welding expertise cannot be readily available and welding conditions either have to be preset for the particular task, or have to be adjusted using either remote consultations with earth based experts, or using some local intelligence, either in the form of a human operator or a computer based "expert system." Such an expert welding machine should also have the appropriate sensing and control capability that would . permit interfacing with the welding process, as well as the necessary intelligence to communicate with the user on a higher level. Furthermore, it should be capable not only of acquiring and using the expertise of welding engineers, but also to correct and improve its performance based on past experience. The work on this area has been extensively carried out by the Welding group of MIT Ocean Engineering department.
In case of interior and exterior repairs, each will have their own set of restrictions and latitudes that will have to be satisfied by the welding systems. For instance, a clean solid-state process would undoubtedly have advantages over an arc process inside the Space Station, from a contamination point of view, while electron-beam welding may prove fruitful in an isolated external application. Also, in the selection of a welding method for a particular repair application, one must consider the properties of the materials to be joined, as well as the specific joint geometries involved.
57 i
Since Aluminum has comparatively high coefficient of thermal expansion it is more susceptible to distortion and buckling from welding operations than other materials. The molten aluminium weld metal will shrink about three times as much as a similar volume of steel weld metal and is generally "the major contributor to distortion in weldments." Solid-state methods on the other hand, do not have this problem since molten metals do not exist. Another apparent disadvantage of using fusion welding methods lies in the affinity of the molten aluminum weld pool for hydrogen. As welding proceeds, hydrogen is picked up by the molten metal from various sources. As solidification of the weld metal occurs during cooling, the solubility of the hydrogen decreases and the gas is liberated, leaving significant levels of porosity in the weldment with a consequent degradation of weld integrity. Prof. Masubuchi~ studied this problem and attributed the suspected sources of contamination to: 1) Moisture on the metal surface. 2) Grease, fingerprints, and other forms of hydrocarbons on the welded surfaces. 3) Hydrogen-containing chemical compounds of aluminum on the metal surface. Aluminum's tenacious oxide layer plays havoc with both fusion and solid-state consolidation methods, each displaying its own level of sensitivity towards its presence [14,24,25].
3.4.2 Present status of space welding R&D
From the above discussion it is clear that as on earth, no one joining technique will satisfy all of the construction requirements on- orbit. The effects of atmosphere, microgravity, vacuum and robotic
58 adaptability all influence the choice of the joining technique for a specific application. Joining method also depends on the hardware configuration of the joint (access to both sides) and material. The additional considerations for an acceptable joining method are minimal power requirements, adaptability to automation and minimal user skill.
Another important consideration is that some metals are easy to weld, and others are difficult to weld. The metals that are easily weldable can be welded in thickness from the very thinnest, about the thickness of this paper page, to the thickest or heaviest produced. The difficult-to-weld metals require special procedures and techniques that must be developed for specific applications. The complex behaviour of material under space conditions will have to be investigated specifically due to the lack of knowledge.
Also the additional primary joining that is done on earth leads to increased volume and structural restriction for launch. Whereas, the more joining that is done on-orbit requires advancement of current welding and joining techniques to take full advantage of the microgravity and vacuum conditions of space.
The main reason for extensive research in space welding is that even though welding is widely used because of its advantages over other joining methods, there are some problems with welding fabrication, one of which is that it is rather complicated and requires some knowledge and skill. It requires considerable knowledge to
59 NUMSER OF PUBLICATIONS 4 6 7 8 9 10
MAJOR EVENTS
- .. .w.. I E 3 GUN USA 5~ SC)YUZ 1 - - - EX-. Ti PE Sc YUZ 6 WELDING ffI'// 70I EB WELD ER USSR SALYUT 1
C LU SKYLAB = cn -. '* -- . .. . -- .,... ~1 I- 75 *. a- BEAM BUILDER
LU
ISO I 1 W7iKF~ N ~W1M EXP. EURO .F E V/ / // - BRAZING SPACE SHUTTLE - L I lEE B I F>I- I fig(7): Survey of space welding publications[24].
60 select the proper welding process for critical work. Our job is to learn enough about welding so we can utilize its many advantages.
For identifying probable joining tasks in space, a survey was made by Prof. Masubuchi and Dr. Agapakis on examining publications on space welding and related subjects fig(7). The study found that serious technical publications on space welding started to appear around 1966. Most of the information on space welding and fabrication has been generated by two countries, U.S.A. and U.S.S.R.
Among the 53 publications on welding and brazing, electron beam welding has been discussed in the largest number of articles. Other processes that have been discussed for space applications include solar energy welding, cold welding and diffusion bonding, and explosive welding. It is clear from the survey that the amount of research done on the space welding is not sufficient and in order to successfully perform welding in space more studies and experiments on welding technologies are an immediate necessity.
Currently the electron beam method is popular. It cannot be. said, however, that the situation will not change in the future. A single welding process can do certain welding jobs, but there are many other jobs which cannot be successfully performed or which can be more effectively performed by other processes. No single welding process will be sufficient to perform all the welding tasks in space. Therefore, it is clear that the selection of the one "best" welding method for use in space structural repair is difficult. Hence, in view of the trade-offs caused by the complex interaction of environmental effects, human factors, and particular application
61 limitations, it would be prudent to equip the space repair facility with several different welding systems to cover a wide range of possible repair contingencies.
We should also start looking at the space welding techniques that are likely to be used extensively in the distance future, say in 2020 or 2050. It is reasonable to assume that GTAW and possibly GMAW processes are likely to be used extensively for welding space structures which will be made in light metals and materials with high strength to weight ratio such as titanium alloys. Therefore, possible use of these processes in space should be studied extensively. Also in developing space welding technologies there are two basic approaches, one is to develop technologies around generic joining processes. The other approach is to select and develop joining technologies which are more suitable for certain structures which need to be fabricated.. For example, if we need to make a long pipeline in space, such processes as high frequency resistance welding may become very attractive.
Therefore, each of these welding alternatives must be analyzed and evaluated in terms of its value, cost and risk characteristics. The value of any welding alternative shall be measured in terms of its contributions to the achievement of each of the goals. The value of each welding alternative should be assessed in terms of the benefits that can be expected to result if it is chosen, and in terms of the regrets that can be suffered if it is not chosen. A focus on the regrets that may occur by not choosing a particular welding alternative can
62 often be very revealing. In some cases, the regrets for an alternative may be so enormous that it must be chosen.
3.5 Resource constraints faced by NASA
Hence from the reasons cited in the earlier sections it is clear that systematic research should be carried out for developing space welding fabrication technologies. But, due to resource constraints faced by NASA space welding R&D is not progressing as it should. At present, research on space welding is at its infancy and not many experiments have been conducted so far. It is usually easier to interest organisations in improving an existing capability than in developing a new one. However, the design of a R&D strategy has to accept that much of the future is unpredictable. In more developed organisation which makes use of strategic management techniques it expected to prepare alternate technologies that can be useful if conditions should change. Especially, in case of high technology research, which encounters frequent and unfamiliar changes an adaptive structure is required.
One of the reasons for this resource constraint is due to the Reagan Administration's military build-up, together with its aversion to increasing taxes and the political difficulty of reducing social security (pension) benefits to retired and disabled persons, this had helped produce a major crisis in the federal budget. From 1981 to 1986 the federal deficit (excess of expenditure over revenue) grew from less than $50 billion a year to over $200 billion a year. At this level it represents a significant fraction of the US gross national
63 product and is having substantial deleterious effects on the government support in space R&D.
Due to these restriction of federally funded R&D to basic and long-lead research programs not many experiments on space welding have been conducted so far and future of increased R&D efforts in space welding remains uncertain. We should remember that the shift to a new technology may take a decade or more to complete, therefore it is crucial to anticipate and develop advanced technologies needed for space activities relatively far in advance. At present cost has become the most important issue in evaluating R&D projects, but this may lead to undesirable results in the future. Therefore, in order to avoid hardships in future in the form of lack of needed crucial technologies one must take a different approach to the evaluation of the R&D investments. In the following chapters the different approaches to the evaluation of the R&D investments and the need for the development of objective tools for rationally selecting and managing the welding technologies for space applications have been discussed.
64 chapter 4
MANAGING R&D
-1 65 chapter 4
MANAGING R&D
Research and development, as defined by the National Science Foundation, includes activities of three kinds. First, there is basic research, which is "original investigation for the advancement of scientific knowledge . .. which do[es] not have immediate commercial objectives." For example, an economist who constructs an econometric model without any particular application in mind, is performing basic research. Firms carry out some basic research, but it is a small percentage of their R &D work. Second, there is applied research, which is research that is aimed at a specific practical payoff. Third is development which is the systematic use of scientific knowledge directed forward the production of useful materials, devices, systems or methods.
In modern industrial research and development programs, basic research is commonly directed toward a generalized goal, such as the investigation of a newly discovered frontier of technology. Applied research is carried on for a specific need. Unified concept of research and development has been an integral part of economic planning, both by government and by private industry. Immediate goal of most industrial R&D is technological innovation. By this means industry either produces technologies which consumers prefer, or produces technologies more efficiently and at lower cost. The consequence of such increases in economic efficiency will be
66 reflected in a higher Gross National Product. Thus technology contributes to growth.
The general expression of the production functions is
Q =f(K, L,T) where K = capital, L = labor, and T is a factor which depends on the state of technology, on the type of techniques available and in use. It is on the basis of this form of expression of the relationship between output and technology that the economist Robert Solow attempted to measure the contribution of technical change to growth in the USA. Essentially, Solow's method consisted of the fitting of a particular form of the production function to data on inputs and outputs in the USA economy between 1909 and 1949. Solow expressed the state of technology as the multiplier (A (t) ) in the production function:
Q = A (t)f (K, L)
His conclusion was that while output per man doubled in the period 1909 to 1949 only 12.5% of this increase was attributable to the use of more capital. 87.5% of the increase was therefore attributable to something else - Solow called it 'technical progress'. By virtue of Solow's definition it is implied that all changes in output which are not due to changes in K and L are due to changes in A.
For the most part, technical progress is due to some kind of systematic endeavor like the contemporary research and development (R&D) programs undertaken by many industrial firms and by research centers funded by national governments. However,
67 real progress in the management of R & D cannot always be - measured by the sum of successful projects. Unfortunately or fortunately, as this case may be each failure represents progress; it's a process of buying information. Consequently, real progress in R&D is a process of sequentially moving beyond failures toward the application of new knowledge.
Unfortunately, the general trend has been to turning more and more to R&D that has immediate benefit. The emphasis, and sometimes overemphasis, on achieving an early benefits from an R&D activity has led to concern that the future health of technology and economy is being imperiled by inadequate support of longer- term and riskier R&D. Investment in R&D contributes to efficiency and output growth by adding to the stock of useful knowledge and by yielding new and improved processes and products. Also R&D plays a central role in the growth and development. Therefore the effective and efficient management of R&D becomes crucially important.
68 4.1 Risk and uncertainty
The successful outcome of R& D programs is manifested either in new types of advanced technology and services. Despite this important role all is not smooth sailing with R&D. There are problems and disadvantages. Research and development costs money, some of it may be quite expensive. In basic and applied research the outcome is so uncertain the expense may be wasted, especially if no new technology result. More important than the greater uncertainty associated with the R&D investment is the greater uncertainty associated with future benefits. Unlike other types of investment R&D investments generally have a higher level of risk (or uncertainty) associated with them. This uncertainty arises from the fact that R&D spending will generally accrue over a more distant time horizon. Furthermore, the lags in benefits from R&D- type programs are usually irregular and very long. Also, the more distant a benefit forecast, the higher the degree of risk and uncertainty associated with it. Therefore in order to achieve maximum benefits the society must postpone or sacrifice a portion of present consumption so that some resources can be diverted to R&D activities.
While evaluating R&D investment it is critical to understand that the R&D risk is a complex topic. It is often confused with the concept of uncertainty. The terms "risk" and "uncertainty" are often used imprecisely as synonyms. Risk exists when a course of action (say, an investment decision) will lead to one of a set of possible
69 A
outcomes (rates of return) with known probabilities. Uncertainty exists when the probabilities of the possible outcomes or the outcomes themselves are completely or partially unknown. The degree of risk can be measured by the dispersion of the probability distribution of the event whose value is being predicted. Uncertainty can be measured by the degree of lack of confidence that the estimated probability distribution is correct.
70 -1
4.2 R&D expenditure vs capital investment expenditure
In general, our decision-making criteria for R&D expenditures are an extension of the decision-making criteria for capital investment expenditures. However, there is an important difference (apart from the difference in tax treatments) between decisions involving investment in R&D, which purchases knowledge, and decisions involving investment in capital, which purchases plants and equipment. The difference is the greater degree of risk or uncertainty (or both) inherent in R&D decisions.
Most of the times capital investment involves present sacrifice for future benefit. Since the present is relatively well known and the future is always unclear, capital investment also involves certain sacrifice for uncertain benefit. Expenditure for R&D can similarly be regarded as certain sacrifice for uncertain benefit. The greater uncertainty associated with R&D expenditure decisions is largely attributable to the fact that a longer projection into the future is required. The level of uncertainty attached to the estimates of sacrifice and benefit is accordingly higher. For example, suppose a capital investment and an investment in R&D are made in the same year. The capital investment could involve expansion of an existing plant or a new plant capacity installation for an existing product. Or the investment could involve building a plant to manufacture a product new to the company, through a licensed process or through the erection by a contractor of a plant. Another possibility is the erection of a plant to manufacture a new product created by past
71 R&D activities. In all these possible forms of capital investment, the magnitude and timing of the "present sacrifice," if not certain, are fairly well known. The future benefits, while uncertain, are believed to commence in a reasonably short time.
The investment in the R&D project, on the other hand, purchases information that is intended to result in a capital investment. As the first step in the process leading to capital investment, the R&D project is automatically some years behind a capital investment project undertaken in the same year. Even after the technical feasibility of an approach is established, it may take five or more years of development engineering and related activities before capital investment is undertaken. The R&D project is therefore only the first link in a chain of expenditures of somewhat uncertain duration and amount.
72 MOOM02--_
4.3 Need for proper evaluation and selection methods
In general R & D is regarded by organizations as a force for growth and survival and as a throttle through which the organization controls its exposure to the uncertainty of future conditions, yet the very nature of innovation is to process new knowledge under uncertainty. The "measure" of uncertainty varies with the class of innovation. For example, product improvements may not be as uncertain as departure into a radical innovation that is characterized by the application of totally new knowledge. It is quite common to discard quantitative methods in favor of simpler "rule of thumb" methods in R&D decision making for project evaluation and selection.
However, the quantitative modeling does not satisfy all the needs of managerial decision-making in project selection and management. Quantitative models cannot "capture" all of the elements encountered in the management of R & D, and to think so is absurd. Indeed, regardless of all the available guidance, the state of the art in the management of R & D reduces to a picture of need for its efficient and effective management. Nevertheless, management science is becoming more sophisticated and the process of managerial decision making in the R & D setting is becoming better understood. Meaningful quantitative generalizations on the value of R&D cannot be made. Since, as in other human activities, individuals and organizations are not all equally good performers. However, we can usefully direct our attention to the financial consequences and implications of a R&D program or ideal.
73 0022922 _
Concern over financial consequences rather than technology is, understandable. The costs associated with the translation of an idea into a reality are high, and the failure rate is even higher. However, an emphasis on early economic analysis can place those with ideas- be they R&D managers or business managers-at a disadvantage unless they understand the rules of the economic game. The understanding of the value of an alternative in terms of its contribution to the achievement of the end results is critical.
4.3.1 Analysis of alternatives
Each alternative must be analyzed and evaluated in terms of its value, cost and risk characteristics. The value of an alternative is measured in terms of its contributions to the achievement of each of the goals. The value of each alternative should be assessed in terms of the benefits that can be expected to result if it is chosen, and in terms of the regrets that can be suffered if it is not chosen. A focus on the regrets that may occur by not choosing a particular alternative can often be very revealing. In some cases, the regrets for an alternative may be so enormous that it must be chosen.
The cost of each alternative must be carefully assessed in terms of its opportunity costs, and follow-on costs. The out-of pocket costs are the day-to-day expenses and capital outlays which must pay out to finance the alternative. Opportunity costs are hidden costs, other opportunities foregone because funds are invested in this alternative. The follow-on costs of each alternative should be very carefully examined. It is not unusual to find that an alternative
74 which looks inexpensive may require massive capital at a later date to implement or maintain it.
The risk characteristics of each alternative should be carefully assessed, in terms of the likelihoods of achieving each of the goals. Some high-valued alternatives may have the potential to make very large contributions to the achievement of the goals. However, the likelihood that they will actually accomplish these potentials may be very small. Other, medium-valued alternatives may exhibit a high degree of certainty of making moderate contributions. Thus, when their risk characteristics are taken into account, the medium-valued alternatives may be the higher-contributing choices.
In general, in most decision situations, multiple goals will exist.
Some of the goals will be more important than - others. These differences in importance need to be carefully expressed as a basis for distinguishing between the alternatives. An alternative that contributes to a highly important goal will generally be a higher- valued alternative than one that contributes to a less important goal.
Theoretically, the alternatives can be ranked from best to worst on the basis of some benefit/cost, regret/cost, or risk/cost ratios. However, it is not possible to include all the relevant factors in such an index. Some of these relevant factors are: the efficiency with which the alternative solves the problem, the impact of the alternative on the goals, and the inter relationships between the alternatives.
75 ii
It is also possible that Judgment, negotiation, and analytical processes may often be used in selecting the best alternative. In the judgmental approach, an individual makes an intuitive choice from among the alternatives. The judgmental approach is often so intuitive that it is not easily documented or explained to another decision maker. Negotiation is a process by which a group of decision makers with conflicting goals exercise judgments, converse about them, and then trade off wants and desires until some agreement is reached. The analytical approach involves factual evaluations and rigorous comparisons of the alternatives on the basis of costs, benefits, regrets, and other measures. The analytical approach includes a quantitative and procedural measurement of values and costs. The effective use of all these approaches in decision making leads to desirable results.
Normally, in the structured decision process, the best alternative is selected on the basis of the application of analytical models and techniques. Operations research and management science methods are used to help the decision maker select the optimum choice, on the basis of economic considerations. Systematic and controlled judgments are incorporated into the process at various points, in order to include non economic and non quantifiable considerations. It is desirable to arrive at a decision that balances off all the various needs and desires. Sometimes a single best alternative may be chosen. Sometimes several alternatives may be found to be satisfactory. More often, no one alternative will be the best on all the criteria or under all the considerations. Then, a
76 package of alternatives may be devised. Or several alternatives may be selected for implementation in a sequence of steps, ranging from the least risky to the most risky. In case of selecting the welding technologies for use in outer space we face a similar situation.
It is critical to note that many of the decisions, based on conscious economy studies involving estimates of expected costs (and possible benefits) are incorrectly made because of the failure of the estimator to reason clearly about the differences between alternatives that involve common elements. Imperfect alternatives are sometimes the most economical. The satisfaction of the engineer's sense of perfection is not a necessary prerequisite for the most economical alternative. Sometimes it happens that a careful study will show that an alternative that at first was summarily rejected affords the most economical solution of a given problem. It is obvious that one way in which study can reach a wrong conclusion is by the omission of an alternative that is better than those that have been considered. Hence we should recognise the value, cost and risk characteristics of each of the alternatives before we decide to abandon a project.
77 4.4 R&D in the public sector
World War I brought home to every government involved the importance of having its armed forces supported by an industry using the most advanced scientific techniques. Since then it has been generally accepted that it is frequently desirable to encourage research and development for reasons of economic growth as well as national security. This has resulted in massive support from public funds for many sorts of laboratories. Subsequently, there was a massive increase in the funding of R&D in the 1940s and 1950s for defense and space. However, the methods used in evaluating R and D in the public sector, have lagged behind this funding increase. Initially, this did not hamper activities because the drive for weapon superiority in the shortest possible time made budgetary considerations secondary. Only in the past 20 years, as R&D methods began to be applied to a wide range of nonwar-related activities, has cost effectiveness become as issue.
While evaluating R&D in the public sector the following aspects should be taken into consideration. We also should note that there are several features that are similar for both businesses and public sectors. First, each has a product or service that is provided as a basis for justifying its existence. These goals are also influenced by a variety of groups, external and internal to the public sector. Additionally, the public sector should conduct an environmental analysis, resulting in a planning base similar to that of the business sector, to determine if the composition or needs of its industry are
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changing or if the organization is losing its ability to meet those needs. Like a business, the public sector may select from several strategies to accomplish its goals. There are also similarities between a public sector and a business in the implementation of a strategy. The means-end chain serves as the implementation framework for both. Their organizational designs are very similar.
However, in the public sector, one must take a totally different approach to the evaluation of a R&D investment. Accounting principles conventional in the private sector cannot be applied. Evaluating investments in R&D that are designed to enhance the welfare of the nation and are therefore classified as in the area of welfare economics. The major analysis technique in this area is the benefit-cost ratio concept. Some of the benefits of public sector R&D is that it provides indirect Federal support for higher education, improves the Nation's Defense posture, increases the size of the pool of scientifically trained individuals, increases the pool of scientific knowledge, encourages the introduction of new and improved processes and products by the private sector.
The economic benefits are that it will improve the nation's balance of payments by reducing the importation of raw materials or finished goods, will render the private sector better able to compete in the international markets, will improve industrial productivity in the private sector, will encourage the introduction of processes and products with a large component of positive social benefits, will speed the introduction of processes and products that will help achieve the national goals. Therefore, it is clear that the methods
79 used in evaluating private sector investment cannot be used for the public sector. This very important aspect has been taken into consideration for our discussion in the following chapters for the evaluation and selection of welding technologies for use in outer space. This modified approach for the evaluation is much more effective and will lead to long term benefits with regard to space developments.
80 chapter 5
EVALUATION TECHNIQUES
81 MMM"
chapter 5
EVALUATION TECHNIQUES
There are many factors involved in the selection of R&D projects. However, they can be reduced to four basic criteria, each of which has an indirect relation to the future benefits of the organization. The first two criteria are primarily concerned with technical considerations; the third deals with the financial obligation assumed in conducting the research and the fourth deals with the strategic elements of the current operations. The four criteria are as follows, a) Promise of success: What is the best estimate of the promise of technical success consistent with known economics and the state of the art? Obviously it is impossible to state the outcome of a research project in advance and, because each proposal tends to be unique, there are no data from which to compute a probability based on experience. The best that a research manager can do is to have someone who is familiar with the state of the art in the welding field and make an expert appraisal of the situation and provide an estimate of the promise of success consistent with known economics. Naturally, with the other criteria having the same weight, welding projects with higher promise of success would be selected. b) Time to completion: How long will it take to complete the research effort from this time forward? Time is an important element, it has value since it reflects the span over which uncertainty will prevail. Here again, the manager of research must estimate the time that is
82 expected to take to develop a welding technology. Other things being equal, a project that can be completed within a specified time is more valuable than one that takes longer. c) Cost of the research: The financial obligation assumed in pursuing the research represents the magnitude of the risk involved. d) The strategic need: Research that contribute most to the organizational needs and goals with the greatest efficiency would be favoured. In addition to these four criteria focusing on the development of alternate welding technologies for contingencies as well as for future needs are crucial, which we have discussed elaborately in the previous chapters. In this chapter financial criteria for evaluating the desirability of the welding technologies are discussed. At first the conventional financial analysis has been considered for the evaluation of these projects then the limitations involved in this kind of evaluation such as failure to consider the complex -relationship between technical uncertainties and financial performance have been elaborately discussed. Therefore, in order to accomodate the uncertainity of future benefits, option valuation techniques and decision tree analysis techniques have been made use of for our project evaluation. The assumption made for our thesis discussions is that benefits are readily expressible in financial terms.
83 5.1 Conventional Financial Analysis
At present, to establish a fair basis of comparison for the costs and benefits of a project the common yardstick used is money. It is, therefore, necessary to express the projects in terms of funding needed and the rewards that may be expected fig(8). Also, dollar estimates of costs and benefits must be placed in the same time frame. For this purpose Net Present Worth (NPW) is the most common technique used for comparing the benefits of research projects. The benefits are usually measured in cash terms that accrue over time.
Net Present Worth (NPW) of the future benefits of a project is simply its present discounted benefits minus its present discounted cost. Discounting is a method used to compare different cashflow over a period of time. The basis of discounting is that money held in the present is worth more than the same sum in future. This is because money held in the present can be invested or make a profit, so that it has an increased value as the time passes.
Thus, the Discounted Cash Flow-Net Present Worth (DCF-NPW) technique compares the project's incoming to outgoing cash flows, with all cash flows discounted for risk and for time. If the analysis calculates a positive net discounted cash flow, the project is accepted fig(8). The general procedure for this technique is to estimate the project's incremental net cash flows, assess the project's overall risk, estimate the opportunity cost of investing in the project by comparison with the expected returns in an equivalent-risk
84 B $ x 103
I I I I I I I I I I 2 ' 3 ' 4 '5 's '6 8 '9 '6
(YEARS) TIME
$ x 103 C I Projected benefit and cost stream for project A.
a $ x 103 4' 111I S 2 '3 '4 '5
C The time stream of benefits at costs for project B. fig(8): Projected benefit and cost stream for projects[32]
85 investments and discount all estimated cash flows at a constant opportunity cost of capital and calculate NPW. The project's contribution of value to the organization is the NPW resulting from an evaluation of the project by the above procedure.
5.1.1 Limitations of this analysis
However, this conventional methods of evaluation has some inherent drawbacks. Since, the estimates required for employing DCF-NPW are technical estimates and financial estimates. In reality the estimates from these two categories are inter-related. The inability of DCF-NPW to properly capture the complex relationship between technical uncertainties and financial performance is a major drawback of the technique. Two characteristics of the DCF-NPW technique account for this inadequacy. They are 1) Uncertainty of cash flows is not properly considered 2) Discounting of cash flows for risk is inexact.
We know that the DCF-NPW technique requires discrete, single point estimates of cash flows. In reality there exists significant uncertainty about future cash flows in any R&D project. Since discrete estimates of all parameters are required for the DCF-NPW technique, the mode or "most likely estimate" is used in most cases. As a consequence of the inability of DCF-NPW to represent the uncertainty of cash flows, the operating options inherent in a R&D project are ignored in the DCF-NPW analysis. In general, the technologies have different operating option characteristics. As uncertainties are resolved over the life of the project, the organisation
86 may choose to abandon, suspend, or expand the project. The freedom to exercise these operating options partially depends on the development technology selected. The flexibility to respond to unforeseen conditions in the future may impact ultimatly on the financial returns of the project. To account for these operating options in the financial evaluation process, the technical selection and financial evaluation must be carried out interactively. Since these operating options can be the source of value to a project with uncertain cash flows, DCF-NPW may undervalue projects with operating options.
Moreover, the DCF-NPW technique requires that all projected cash flows in the future be discounted to equivalent values at a common point in time. These discounted cash flows are summed to calculate a net value, usually at time zero before the initial investment is made. This discounting procedure adjusts for the riskiness of the cash flows and the time value of the cash flows simultaneously. But the drawback is that a singular discount factor is applied to all cash flows throughout the life of the project. The assumption inherent in using a constant risk adjusted discount rate is that the ratio of the certainty equivalent of a cash flow to its expected value decreases over time at a constant rate. This assumption may not be valid in the case of a R&D project. Since R&D projects pass through several phases of varying riskiness. The application of different discount rates for these phases is not generally accommodated with conventional DCF-NPW techniques.
87 In addition, another controversial question occurring in this analysis is the "correct" investment factor or, more precisely, the "social discount rate" to be used to calculate the present value of future costs and benefits of a project. The intuitive choice of a social discount rate which is incorrect may lead to wrong conclusions. Also DCF-NPW evaluation determines the abandonment time and the project value from single-point estimations of cash flows. This approach fails to properly capture the value of the abandonment options. A project's owner decides whether to abandon at any point in time based on the prevailing conditions at that time and based on expectations of future conditions. The optimal abandonment strategy under uncertainty will be different from the DCF-NPW abandonment strategy. Furthermore, the project's expected value with the optimal abandonment strategy usually will be greater than the DCF-NPW calculated from single-point estimates.
Thus, the traditional financial evaluation techniques such as DCF-NPW do not accurately capture the realities of the project. The dilemma of project evaluation then becomes reconciliation between the need to accurately model the investment decision and properly value the cash flow. Alternative financial evaluation techniques have been developed to substitute for or combine with DCF-NPW techniques in an attempt to better deal with the uncertainties of outcomes represented by risky projects. Examples of alternative evaluation techniques are option valuation and decision-tree analysis. The following section discuss how these techniques can be
88 I
adopted in our evaluation process in order to make an effective choice of welding technologies for outer space.
89 5.2 Alternate methods of evaluation
5.2.1 Option pricing evaluation
Options valuation techniques provide some remedies for the two basic criticisms of the DCF-NPW method. Uncertainty of future benefits can be accommodated with options valuation techniques. In addition, options valuation techniques do not require the estimation of a discount rate. Most situations involving options can be considered to be call options or put options, but they occur in many guises and frequently in combinations. Call options provide the owner with the option to make an investment or to acquire an asset. Put options provide the owner of an asset with the right to dispose of it on favorable terms. If the investment opportunity will not be available in the future, or if the investment opportunity is certain to be worth less if it is undertaken at a later date, then the NPW is the appropriate decision criterion. However, if it is feasible to delay accepting the investment and there is a chance that the investment may become more valuable in the future because of changing conditions, then the decision about whether or not the investment should be undertaken immediately is comparable to the decision to exercise a call option. This is exactly the situation faced in the case of space welding technology development.
The owner of a R&D project has the opportunity to respond to the resolution of uncertainties in ways that maximize the value of project. If such action capabilities did not exist, fate would dictate totally the ultimate project value. Although uncertainty about a risky
90 I
project cannot be eliminated, uncertainty can be reduced to some extent. Furthermore, management can actively respond to the evolution of the remaining uncertainties. Such opportunities for action responses are termed operating options. The following operating options exist in a typical R&D program
- The option to wait to develop
- The option to abandon the project
- The option to expand the project
- The option to temporarily suspend the project
- The option to switch technology
The advantage is that the operating options may or may not be exercised. Also the owner has to exercise the option at the opportune time. For all these reasons, operating options may add value to a project
Thus it is evident that the R&D expenditures are in many ways parallel to the American call option which will permit the owner to purchase stock at a specified price (exercise price) at any time prior to an agreed upon expiration date. The value of a stock option varies with stock price as shown in the fig(9). In establishing the parallel between the R&D option and the stock option: 1) The price of the call option is analogous to the cost of the R&D program. 2) The exercise price is analogous to the cost of the future investment needed to capitalize on the R&D program when the investment is made. 3) The
91 -J ~1 4 I-) lA~ 0 w -J 4
45 S i EXERCII E PRICE VALUE OF S TOCK (S) (CALL EXPIRES OUT OF T14E MONEYI (CALL EXPIRES IN TIlE MONE'!I
fig(9): Value of a call expirationl331. FACTOR IiVESIMENUT CALL QPTIQN B&D PIN
I. Downside Risk nisk substantial. * Call expires out-ol- or gan - does not make May lose complete the-money. major investment- -lose the investment. . Do not exercise option. cost of the R&D project. (May and thus lose the cost have gained valuable insights of the option. for future R&D and other opportunities.)
VALUE DECLINES VALUE INCREASES VALUE INCREASES 2. Uncertainly As uncertainly o Volatility increases the Wide array of speculative or (Volatility) outcome increases. Value ol Option upside partially defined applications Iicusases NPV is discounted potential without (as with more basic due to risk aversion. Increasing downside innovations) Increases the risk. upside potential without increasing downside risk. ICost of R&D I
.ALUEDEC IMEF VALUE INCBEASES VALUE INCHEASES 3. Time Ireases Longer payback Increased probability Option to make investments discounts value. of exceeding a given (as yet not completely exercise price. defined) over a prolonged period is much more attractive than a short range or limited window of application
Table(3): Investments, options and R&D options[36]. value of the stock for the call option is analogous in the R&D case to the benefits received from the investment. Table(3) illustrates the difference between options and investments and the direct parallel between R&D options and stock options.
Just like the stock option, the downside risk for the R&D option occurs when the organization, for whatever reason, does not make the follow up investment necessary to capitalize on the R&D program. The equivalent loss is the cost of the R&D program, which in general will be much smaller than the follow up investments. Regarding volatility, R&D options parallel the call option in that R&D programs which address high impact opportunities with a modest or low probability of success, do not imply higher risk. With respect to timings the parallel situation for the R&D option is that R&D programs offer flexibility in the timing of the -subsequent investment or financial commitment, and particularly those providing the opportunity to make a series of investments over a period of time, should be preferred to those projecting a short range application. R&D options have one very important advantage over stock options. The purchase of a stock option has no direct effect on the exercise price or the future price of the stock, whereas the major purpose of the R&D option is to influence the future investment favorably, either by lowering costs- or by increasing returns. This fact should be fully utilised in case of space welding technology development.
Despite the above mentioned significant advantages, current options valuation methodologies have some drawbacks which minimize their usefulness for evaluating risky projects. However, the
94 development of options theory and its application to capital projects is progressing rapidly. In time the shortcomings may be remedied. For example, it may be possible to model the technical uncertainties by employing a sequential series of options. Another possibility is a combination of options techniques and Monte Carlo Simulation.
Thus, there is no question that the application of option theory to capital budgeting decisions will be a major capital budgeting development of the next decade, and managers involved in a firm's capital budgeting process should understand when these concepts can usefully be applied. Even where exact quantitative results cannot be obtained, option theory makes an important contribution by calling attention to the existence of the alternatives and the need to value flexibility that results from a given investment alternative.
5.2.2 Decision tree analysis
Decision Analysis (DA) or risk analysis requires that the possible outcomes, along with their probability and the value of each outcome to the decision maker, be established in advance. This involves serious practical difficulty. However, DA does proceed in a fashion that appears logical and straightforward. Thus it overcomes one of the difficulties common to most other analytic techniques.
In quantitative analysis, risk is generally measured by probabilities. There are basically two ways of estimating probabilities: the objective way and the subjective way. An objective probability is the proportion of times an event has occurred out of the total number of times it could have occurred. Historical analyses
95 fig(10): Basic diagram of a decision analysis[30].
Pu A Ou'TCOME
B P C
Dp + PI- 1.0 0'
Decision Box
0 PSI X OuJTCOME
z may be used to establish frequency counts of past events, which may be converted to proportions or probabilities of occurrence. For instance, if 5 of every 10 projects have failed in the past, then it may be objectively claimed that the probability of project failures is 5/10 = 0.50. A subjective probability is an index of personal belief. For instance, a subjective probability number of 0.70 simply means that the individual feels the odds are 7 to 3 that this event will occur. A subjective probability need not relate to any objective probability whatsoever. In many cases where subjective probabilities are used, the particular event may be a unique event that has not yet occurred, i.e., the outcome of-a new project. A subjective probability is an expressed judgment, based on personal experience and insights. The subjective probability number is an index, on a scale from 0.0 to 1.0, that reflects the individual's felt judgment- that the event will occur. DA uses subjective probabilities and the Bayes theorem to extend its range.
The decision tree analysis requires the following steps. For example, if the problem can be cast in the form of fig(10), one can choose the more appealing option by calculating the Expected Monetary Value (EMV) of each branch. A decision is represented by a square box and subsequent chance outcome is represented by a circle. There is a cost associated with making the decision. Probabilities are placed on each outcome and the sum of the probabilities must be unity.
We can easily incorporate the different conditions faced by a R&D project such as waiting to develop the project and abandonment
97 of the project in the decision tree analysis. For example, suppose a decision from among three alternatives is required at time=0. If no investment is made initially, one can wait for say, six years, at which time the same investment alternatives are available. Thus, the opportunity to invest exists only at time=0 and time=6 years. The opportunity to abandon the project is available at time=6 years, after the initial investment is made and uncertainty about field size is resolved. Thus abandonment options are artificially constrained to only one time period. In reality the project could be abandoned at any time. Limiting the possible investment and abandonment alternatives is necessary in order to keep the number of tree branches at a practical level.
Fig (11) shows an example. Development costs are estimated to be $100,000 and there is a probability of 0.7 that the development will be technically successful. It is estimated that there is a probability of 0.4 that the product will be highly successful and that it will produce an income of $400,000 (after subtracting the development cost). There is probability of 0.4 that the product will be moderately successful and the income will be $100,000 (break even) and there is a probability of 0.2 that the product will be a failure and that it will lose $100,000. The EMV of each outcome is shown in the figure. The total EMV for the value of the decision to develop the product is the sum of all the expected outcomes, $26,000. The value is compared to the EMV of the alternative decision of not developing the product, which has a value of zero. Thus it is evident that decision tree analysis can be employed to
98 fig(I1): Simple decision tree for product development[30].
INCOME P EHV HIGII.Y SUCCESSFUL $300,000. 0.28 $84,000 - +$400,000 6
P0.4 MODERATEL.Y SUlCCESSFUL $0 0.-28 $0
$100 00 1*0 -200,000 0.14 -$28,000
0.30 -$20.000 ST ART -$100.000 1.00 $26,000
$0 1.00 $0 arrive at a much more effective decision making when compared with the conventional DCF-NPW techniques.
However, one of the drawbacks of traditional decision analysis is that it allows only a few possible outcomes. This drawback can be overcome if we incorporate Monte Carlo Simulation techniques into decision tree framework. Monte Carlo Simulation recognizes uncertain- quantities as continuous probability distributions rather than discrete estimates. Each uncertain variable is represented typically by a cumulative probability distribution. The probability of the random variable taking on a value less than or equal to a specific quantity is assigned a probability between 0 and 1. In this manner, all possible values of the variable are represented, unlike traditional DA where only a few possible outcomes are allowed. Monte Carlo Simulation techniques can be efffectively incorporated into the decision tree framework to overcome this drawback. Instead of permitting a few branches from each chance node, a continuous probability distribution is used at a chance node to demonstrate the entire range of possible outcomes and their likelihood of occurrence. The primary advantage of Monte Carlo simulation is that it permits an accurate description of the uncertainties about the input variables of the investment decision. This uncertainty is then translated into uncertainty about the output variables, for eg., NPW of the project.
Thus it is quite evident that instead of using the conventional financial techniques if we use the option valuation technique and decision tree analysis we could be able to analyze the alternatives available in a much more effective manner. Each of the welding
100 A
alternatives can be analyzed in terms of its value, cost and risk characteristics by making use of these methods, these methods recognize that a small investment in the R&D at present may become more valuable in the future because of changing conditions. Therefore, the dangers involved in over reliance on a single space welding process should be assessed realistically with the aid of these objective evaluation tools. In the following chapter we focus on the strategic management approach that could be employed in order to overcome the resource constraints that are affecting progress in the space welding technology developments.
101 chapter 6
STRATEGIC PLANNING
102 chapter 6
STRATEGIC PLANNING
6.1 Benefits of strategic planning
Organizations tend to adopt a planning process and develop strategies by rote, without actually thinking strategically. They can significantly improve their value of their planning by better understanding and facilitating strategic thought within their planning process. Of course, there is no need to develop rigid medium to long term guidelines, but a sense of direction based on overall medium to long term objective is necessary so that opportunities are not missed. Therefore, organizations must think strategically. They must translate their insights into effective strategies -to cope with their changing circumstances. They must develop the rationales necessary to lay the groundwork for the adoption and implementation of their strategies..
The key questions that are helpful in stimulating organization to think strategically are 1) What is likely to upset organizations expectations? and what might be its impact if it happened? and 2) What important opportunities are organization currently foregoing? This kind of effective environmental assessment should provide several benefits to the organization. Among the most important is that it produces information vital to the organization's prosperity. It also helps to identify potential source of vulnerability and prepare contingency plans if the vulnerability ia likely to result
103 in disaster. Moreover, it is difficult to imagine that an organization can be truly effective unless it has an intimate knowledge of its strengths and weaknesses in relation to the opportunities and threats it faces.
A strategy is a unified, comprehensive, and integrated plan that relates the strategic advantages of the organization to the challenges of the environment. It is designed to ensure that the basic objectives of the enterprise are achieved through proper execution by the organization. Plans, objectives, and goals are all important elements of the planning process, but the strategy is the basis of the thinking process. Strategy includes the determination and evaluation of alternative paths to achieve the objectives and mission and eventually a choice of alternatives that is to be adopted. Inherent in the process of strategy selection is the requirement that strategic alternatives must be identified. The view of continuous change rather than a set pattern requires continuous effort to keep the strategy upto date. When viewed in totality strategy is really. the result of a continuous process. Therefore, strategy is a bridge between the organization and it's environment and understanding of strategic issues and development of alternate strategies are critical in the survival of any organisation.
The strategic issue is defined as the fundamental policy choice affecting an organization's mandates, mission, values, cost, financing, or management. Strategies are developed to deal with strategic issues, that is, they outline the organization's response to fundamental choices. A number of benefits ensue from the 104 identification of strategic issues. The main advantage is that attention is focused on what is truly important. Thus, identifying strategic issues is the heart of the strategic planning process. The purpose of this step is to identify the fundamental choice facing the organization.
One of the advantages of strategic planning (SP) is that it sees the organization as a whole in relation to its environment. Such a view keeps the organization from being victimized by the present. Strategic planning is defined as a disciplined effort to produce fundamental decisions and actions that shape and guide the organization. SP requires broadscale information gathering, an exploration of alternatives, and an emphasis on the future implications of present decisions. Most of the time, SP & Long Range Planning(LRP) are used synonymously. But in practice they differ in the following fundamental ways. SP relies more on identifying and resolving issues, while LRP focuses on specifying goals and objectives. SP emphasizes assessment of the environment far more than LRP does. SP is much more action oriented than LRP. SP considers a range of possible futures and focus on the implications of present decisions. Strategic planners may be guided by vision of success, but they know that different strategies may need to be pursued to achieve this vision if the future does not turn out as planned.
Therefore, we conclude that the main benefits of SP are that it clarifies future direction, establishes priorities, makes today's decisions in light of their future consequences, develops a coherent 105 and defensible basis for decision making, and deals effectively with rapidly changing circumstances. Also, SP also forces us to extend ourselves in unfamiliar areas and it forces us to adopt a broader goal structure for the organization than usual. SP forces us to extend our time horizon. By employing this approach it becomes evident that we cannot restrict ourselves to normal short-range operational goals at least in the initial phases. Many choices made intuitively or thought to be "don't care" choices also become differentiated. Future opportunities and difficulties receive early recognition. Available options are highlighted. Therefore one must not restrict thinking to status quo. Premature closure of a project must be resisted and all possible alternatives must be considered with an open mind.
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6.2 Strategies Therefore, by effectively employing strategic management approach NASA could generate sufficient funds to invest in the development of space welding technologies. Following are some of the strategies NASA could employ in order to overcome the resource constraints: international co-operation, commercialisation of the space and university research. 6.2.1 International co-operation With military confrontation among major powers declining, economies expanding around the world and astronautical proficiency rising, the next 40 years should see a global surge of investment on the space frontier. The Soviet Union is well on the way towards establishing a permanent human presence in space and may be in the early stages of preparing for a human mission to Mars. Moreover, Soviet Union's space policies are based on the principles that all countries have the same rights to space, and that the use of space should have entirely peaceful purposes. The Soviet Union has kept to these principles since the beginning of the space era. The capabilities of other space powers are also continuing to improve. European and Japanese have impressive scientific and technical resources as well as growing space capabilities and by the late 1990's both Europe and Japan may have their own manned launch systems. Thus these space powers can bring significant scientific, engineering, and financial resources to cooperative efforts in space. Additionally, the agendas of these space powers overlap with US. However, they too face financial strains in realizing their space agendas. Thus international cooperation could be important in bringing these
107 proposed projects to fruition. The United States recognized this when it invited Western European nations, Japan and Canada to join the U.S. in building a Space Station. This approach should be adopted in case of developing advanced technologies to be used in space as well. Properly designed international cooperation could accelerate human expansion into the solar system. The models for international co-operation in developing advanced technologies for use in outer space can be as follows 1) A selective multilateral one, in which US could work with two or more foreign partners, as it is doing in the Space Station, another example of this kind of co-operation is the Inter Agency Consultative Group (IACG), consisting of the space agencies of the U.S., the U.S.S.R., Western Europe, and Japan. Originally established to coordinate missions to Halley's Comet, the IACG is now coordinating the International Solar Terrestrial Physics program. 2) The second model could be an inclusive multilateral one, in which all interested nations could participate. One precedent for this might be the Space Agency Forum for International Space Year, which includes 23 space agencies from around the world. The International agency thus created shall undertake activities and research programmes for developing advanced technologies for use in outer space. The funds for the organization can be obtained from its members. International co-operation in space studies is practically a matter of necessity for two main reasons. The first relates to logistics and remote locations. The second principal reason is that there are only a limited number of experts trained in space welding. Scientists engaged in space research in space are dependent on very 108 limited resources in transportation and supplies; therefore, it -is essential that these scientists make optimum use of combined facilities. These kind of scientific programs are critically dependent on logistics. Especially, the transition from broad exploratory investigations to problem oriented research programs increases the complexity of logistic support, because the later involve more numerous, detailed, and sophisticated measurements. It is a known fact that the space welding must be performed in locations extremely far from the earth, where there are not large number of people with vast knowledge and experience and no abundant amount of tools, consumables, materials and energy resources. Also no one country boasts a large amount of talent in this highly sophisticated field. Consequently, it has been implicitely recognized that the small number of specialists. in this area must to one extent or another join forces in order to achieve progress in this complex field. The model to be followed in sharing the space welding expertise and equipments can be similar to that being followed for Antarctica Research. The scientific co-operation in Antarctica involves a high degree of co-operation among the scientists of many countries and stations in Antarctica. Also the international co- operation in Antarctica includes not only scientific co-operation but also logistic aid from one country to another; transport, rescue, search, and assistance by ships, ice breakers, and airplanes of the various countries to personnel of the other countries under the Antarctica Treaty. A similar arrangement between space faring nations will be very beneficial for everyone of the participating countries for the reasons stated above. 109 6.2.2 Commercialisation of space
Space has long been the province of national governments only. Since Sputnik was launched in 1957, the only effective participants in exploration of space and exploitation of its resources have been governments or quasi-government entities. Governments provide funds for space research and development. In terms of aggregate investment globally the overwhelming proportion of expenditure so far has been by governments either individually or inter- governmentally in jointly funded projects. These are projects that are ultimately financed by the taxpayer in various parts of the world, but not generally by the private saver. However, at present there is an increased need for the funds as expenditure in space has increased due to the increased importance of the space activities. Therefore, it will not be possible for the government to fund the entire space research. Hence steps should be taken to attract private funds for the development of space activities. The major facilities required for commercial applications in space can easily attract private funds. Hence this possibility should be exploited thoroughly for the benefit of space research and therefore now is the time to shift the space funding burden to the private sector to the greatest extent possible.
At present, the way the space programs are conducted are inefficient for a number of reasons. From the U.S. perspective especially, "business" in space has not been conducted as a business at all, but rather as a series of federally funded programs, subject to both the uncertainties of budgetary cycles and the inherent
110 inefficiencies of large bureaucratic organizations. When the National Aeronautic and Space Administration was established, Congress contemplated the development of a private sector space industry. Congress intended that the industry would pass to the private sector. To this end, NASA was to register all patents on the public record in order to give the private sector the opportunity to capitalize on the fruits of invention and further advance the state of the art. Thus, in the U.S.A. much of the technology was effectively passed on for development, at low or no cost to industry, whereas in U.K., the knowledge generated in the research establishments were gradually commercialized and benefits passed on to the private sector either directly or indirectly.
Another startling example of NASA's missed opportunities for generating revenues should bring the problem into sharp focus. NASA has never charged a television network for the rights to televise manned space launches. ABC, CBS, and NBC have always been invited along for the ride, free of charge. In and of itself, this does not seem particularly earthshaking. That is until one realizes the commercial value of those broadcasts. Television today is a multi-billion dollar enterprise. Advertising time during Super Bowl XXIII ran a staggering $1.4 million a minute. ABC paid the International Olympic Committee $309 million for the rights to broadcast the 1988 Calgary Winter Olympic Games, and then spent an additional $390 million to produce and air its 94.5 hours of sports spectacular. The price tag for a 30 second spot in prime-time (8:00 p.m.11:00 p.m. EST) was $600,000.
111 What does this have to do with space? Simple. NASA is precluded by its statutory mandate from charging for the right to broadcast space missions. Private companies are not so constrained. Private enterprise in space has this distinct advantage over government, an advantage which, in the case of publicity rights alone, is worth billions of dollars. Publicity rights extend beyond just broadcast rights, and private enterprise may well be able to enter joint ventures, barter agreements, or otherwise reduce the cost of space activities through selling slices of the publicity pie.
Also, if any consideration is given to eventual revenues to be gained from space, those revenues are either assumed to be nascent for many years to come, or assumed to come only from government purchase of space facilities and products, whiich does nothing to lower the overall cost of exploration and exploitation. The outer space environment is now rich in opportunities for entrepreneurial business organizations. Thirty years ago, the prospects of private economic potential from space were barely recognized. Today, the communication satellite industry alone, born with the space age, is a multibillion dollar a year enterprise. The commercial satellite industry is a good example of a case in which the U.S. industry has credit for research, development, testing, and manufacturing, a case in which the U.S. industry has gone from the drawing board to the commercial exploitation of space. This shows that the commercial applications can easily attract private funds. Therefore, NASA should not continue to miss the opportunities for generating revenues by commercialisation and immediate steps should be taken to shift the
112 space funding burden to the private sector to the greatest extent possible. Also, in general the publically funded spending tends to be bureaucratic and less likely to achieve an economic return than privately funded spending.
Some of the sources of private funding for space related activities are: 1) Venture capital: This is direct investment in new companies. The form of investment is usually equity or a form of debt that will be converted ultimately to equity. An initial investment is usually followed by several more at staged intervals. 2) Banks and institutional debt market: This market has the capacity to support the largest known commercial projects. Funds are usually supplied by small groups of large publicly or government owned banks and insurance companies. 3)Publicly owned debt and equity: In this case, debt obligations and equity are sold to the public. This is an international market with the capacity to finance virtually any known commercial activity. 4) Limited partnerships, joint ventures and closely held corporations: These are forms of organizations where corporations and governments with corporations join together to form operating companies that need large amounts of capital but entail substantial business risk. 5) Research and development limited partnerships: This is a type of organization where high income people join in a partnership to develop a technology and sell it to a company which will then use it in its line of business. The incentives to the investors are royalties
113 from the use of the technology and income tax benefits obtained from financing research and development.
There exists a number of space projects that can be easily attract these private funds. For that purpose projects that are regarded as commercially viable now and in the foreseeable future are: (i) ground facilities, launch, landing and monitoring; (ii) launch vehicles, including reusable vehicles; (iii) satellites, for a variety of applications; (iv) space laboratories; (v) space stations.
Presently, Johnson and Johnson have an exciting joint venture for the manufacture of pharmaceutical in space, which includes drugs for haemophilia, a one-shot diabetes cure, a blood-thinning drug and a human growth hormone drug. Clearly the markets for such products are enormous and the investments involved are likely to run into hundreds of millions of dollars. A company called Microgravity Research Associates is at present working with NASA on the manufacture of gallium arsenide in space. This substance is one that may according to some claims, eventually replace silicon for advanced computer chips. Union Carbide is involved in the development of specialized materials manufacture in space and is already experimenting with metallurgical furnaces in these conditions. Fibre optics is another area of relevant technology where space conditions appear, in principle to solve certain ' stringing problems and a number of companies are working on this technology. From these evidences it is very clear that it will not be difficult to attract private funds for these kind of projects.
114 There has also been a great deal of interest in the possibility of privately funded launch vehicles. Fairchild have a highly developed proposal to provide a space platform that would be available on a lease basis for customers with requirements going from quite small to large. The estimated cost of developing the first platform is approximately $200 million and there appears to be considerable industrial and financial interest in the project. Also, dramatic lowering of launch cost expected in near future will have a substantial effect on the economics of space manufacturing. Therefore, NASA should make use of this increased interest of private sector and should take all efforts to encourage the commercial infrastructure development.
When we analyze the future of space development, it is clear that only those who can afford it will be able to take advantage of the vast resources of space and its potential for monumental improvement of the human condition. And only those who can find a way to make money in space will be willing to lead the way in the research and development. Therefore, in order to encourage the business outlays that may lead to innovations, liberal tax credits shall be granted for space R&D expenditures. In the following section funding university research as a cost effective method to gain access to space welding expertise has been discussed.
115 6.2.3 University Research
The framework for government/university relations was established during and immediately following World War II. Prior to that time, government funding for academic research was relatively limited and concentrated in a few specific areas, especially agriculture. During and after the war, support for scientific research came to be viewed as a legitimate role of government. Universities are a natural home for the scientific research, since their faculties and research laboratories are well-established, and they have a steady supply of advanced students who could receive their training while assisting in the research. Also the universities are an excellent and convenient source of technological expertise and they offer an ideal source of instant expertise.
Universities also offer the important benefit of being relatively cost effective places to gain access to expertise. Therefore, NASA can achieve its research objectives at less cost through funding university research than it can by conducting the research in its own laboratories. This cooperative R&D offer substantial benefits in a varity of forms. For eg., it offers an opportunity to overcome, atleast in part, the serious shortcomings in NASA research spending. In case of the universities such cooperation can yield not only additional research resoures but also new intellectual challenges which can result in society-wide benefits. These add up to a more exciting and challenging environment for teachers and students which in turn leads ultimately to better educational programs. Since improved. 116 cooperation between universities and NASA can help NASA to deploy its R&D resources more effectively this opportunity should be exploited aggressively. So far in all our discussions even though we have been discussing the development of the welding in space, there are several possible uses for these concepts for non-space applications. In the following chapter the benefits of developing space technologies and the possible uses for the concepts developed for non-space applications have been analyzed.
117 chapter 7
BENEFITS OF DEVELOPING SPACE TECHNOLOGIES
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chapter 7
BENEFITS OF DEVELOPING SPACE TECHNOLOGIES
People often ask, "Isn't it a waste of money to go into space? Why shouldn't we spend that money here on the Earth instead of throwing it away in space?" It is not a correct assumption since that money is being spent on this planet. It's being invested in helping us find the resources we need to grow as a civilization. It is, in fact, helping us solve many of our global problems. And that money saves lives as well. The average person speaks of Earth with little awareness that it is just one small planet in the vast universe. Only from space have we begun to look at what our planet really is, a small blue ball, floating in an endless vacuum, moving around an ordinary, insignificant star, just one of hundreds of billions in the Milky Way galaxy. Only from orbit can we see many features too big for us to perceive on the ground. From space, we can see the outlines of huge craters where meteorites once hit this planet, remnants of the forces that first formed our world. Only from space can we begin to get a complete picture of the world's weather and climate. Instead of taking thousands of measurements from random points on the surface of the Earth, we can now take a photograph of an entire hemisphere of the planet in one moment, and watch the storms and clouds and rain and hurricanes and snow unfold in mysterious, intricate patterns.
Satellites now routinely allow us to monitor the Earth's crops; we can spot agricultural blights before they spread too far to control.
119 We can find geological resources from space; telltale formations where minerals or oil lie hidden often can be seen from orbit. Scientists have developed increasingly sophisticated spacecraft that can monitor the Earth's surface at many different frequencies, not just with visible light, but with infrared and ultraviolet light, and with microwave frequencies, too. Different rocks and plants, and snow cover, emit distinctive patterns of frequencies that a computer can be programmed to detect. Pollution can also be monitored similarly. Until we began to watch the Earth from space, we couldn't make many observations essential to our progress that simply cannot be made close up.
Unknown thousands have been saved by the weather satellites that detect the motion of hurricanes and other storms. Without the advance warnings from these satellites, many people would have died in the terrible -storms and hurricanes now routinely observed from space. One of the most exciting space developments in recent years may even prevent starvation in many countries. We may find hidden water sources with which to help stem the droughts that plague inhabited areas on the fringes of the desert, and thus prevent mass starvation.
One of the most important things we can do in space is to watch for any changes on our own planet. There is, for instance, a growing suspicion that Earth is getting warmer and may suffer from a "greenhouse effect" like Venus. If so, the climate of the future may be radically different from now, and the effects could start to become apparent in the next decade or two. Droughts may hit places that
120 ordinarily have good rainfall. Shorter growing seasons could cause massive, worldwide food shortages. If this effect continues into the next century, the polar ice caps might melt sufficiently to flood coastal cities. The main cause of this alarming trend is the widespread burning of fossil fuels such as coal and oil, and even wood. All these fuels are carbon compounds-organic chemicals-and when they burn, the oxygen in the air combines with the carbon to produce carbon dioxide. Carbon dioxide builds up in a thick layer over the whole Earth, eventually acting much like the walls of a greenhouse, keeping us warmer than we'd otherwise be.
The whole picture is so complicated that no one can confidently predict what's going to happen. On top of all the factors immediately visible, we know there have been ice ages and tropical ages in the distant past, long before humanity began to fiddle with the planet. Clearly we can expect changes in Earth's climate, independent of our actions. The only way we can know whether we are going to trigger climatic disaster or not is to study the atmosphere and the oceans, the forests and farmlands, from space.
Asteroids also present a potential hazard to Earth. For example, one called Hermes passed only half a million miles from the Earth in 1937. That's just twice as far away as the Moon, incredibly close by astronomical standards. Even the impact of a small asteroid could be disastrous. Many scientists now think, for example, that it was an object only about ten miles in diameter that hit the Earth 65 million years ago and created an enormous explosion, covering the Earth with a dark cloud that prevented sunlight from penetrating,
121 drastically lowering the temperature, killing off much plant life, and extinguishing many animal species, including the dinosaurs. Such a collision would release more destructive energy than all the nuclear weapons on Earth today. The smaller these objects are, the more likely one of them is to collide with the Earth, because they are so numerous. But the problem is that small objects are extremely difficult .to spot from afar. Usually they cannot be detected if they are very small until they are relatively close to the Earth, at which time we would have little chance to react to them. Some scientists have suggested that we create a sky survey to watch for such asteroids, so we can prevent them from hitting the Earth. It is inevitable that sooner or later a small asteroid will hit us with the energy of a H-bomb; but if we could detect its approach in time, we could send missiles into space to divert or destroy it.
One of the important benefits from the space activities is the improvement in medical care which has been revolutionized by sensors and monitoring systems developed for astronauts. Another benefit is with regard to world population. Earth is already overpopulated by many measures, and the population continues to increase, even if at a slower rate than before. Billions of people will be added in the next decades. To overcome this problem of overpopulation several of the moons and planets can be transformed into livable places with the technology that should become available in future centuries. The human race stands now on the threshold of a new frontier, whose richness surpasses a thousand fold that of the new western world of five hundred years ago. That frontier can be
122 exploited for all of humanity, and its ultimate extent is a land area many thousands of times that of the entire Earth.
If we build new lands in space, starting from the Earth, we are the "gravitationally disadvantaged." We are at the bottom of a gravitational well 4000 miles deep, from which materials can only be lifted into space at great cost. Our technique must exploit the fact that the Moon has a gravitational well only 1/20 as deep, and as we now know from the Apollo samples is a rich source of metals, glass, oxygen, and soil. The Moon has a surface area roughly equal to one of Earth's continents. Probably every metal needed by civilization is there in enough abundance to supply the Earth for the foreseeable future. The question is whether this world of resources can be made available to us at a reasonable price. When we think of going into space, we think of the huge rockets required to get us off the Earth. Many people assume that it would require a similarly huge project to get any resources off the Moon and into space. But, as pointed out earlier, that effort would be much less on the Moon than on Earth.
If we were to mine the Moon and process the materials there, we could shoot them off the surface of the Moon with relative ease, perhaps using electromagnetic catapults, something like those that launch airplanes off airplane carriers. The materials could be caught by factories orbiting the Earth and used to expand them, as well as to build larger space colonies, eventually perhaps exporting further- refined lunar materials to Earth. Microelectronics shows no sign of slowing its explosive growth, and micromachinery looks like it's going to follow the same path. And the power of computer software
123 continues to increase dramatically, making those small packages ever smarter. By combining the advances in these technologies effective
electromagnetic catapults can be built efficiently. At first, of course, the space construction would have to be supplied from the Earth, but later on, we'd be able to supply most of the needs of the space dwellers from lunar resources. The catapults used for this purpose would mean great savings, since they would eliminate the need for chemical rocket fuel. Catapults are driven by electromagnets, powered by solar energy or other sources. In the laboratory, scale- model catapults of the type needed to get materials off the surface of the Moon have already been built.
There are many number of benefits that are to be derived from the use of space station as well. If we have people living up in space day after day in zero-gravity, and able to modify their research as they get new results,- devising new experiments on the spot that don't have to be planned and approved years in advance, they will undoubtedly make discoveries we cannot guess at now. In the long run, a Space Station could pay for itself in both the practical and scientific fruits of its research. Also the Space Station would be the place to start testing what may be the main power source of the 21st century: solar-powered satellites. As Peter Glaser has shown, solar energy can be efficiently converted to electricity in space and transmitted to Earth as a microwave beam. As everyone knows, the Sun is a virtually inexhaustible source of clean energy. It is difficult to use on Earth as more than a small supplement to other sources, though, for two reasons one is that though solar energy is available
124 full time in space, on Earth it is cut off by nighttime, by seasonal variation in the day-length, and by clouds and secondly the low average intensity. Hence for these reasons it is more efficient to tap solar energy in space.
The solar energy that is tapped can be used for cheap space travel and can be adapted for human spaceflight, making it easier to colonize places like Mars. The physicist Gerard O'Neill believes that solar energy will be the biggest economic benefit of space for the foreseeable future, and could replace most of civilization's dependence on fossil fuels and nuclear power. Many of the techniques he and his colleagues propose need to be tested in space, and the Space Station is the ideal place. One of the scientific predictions for space activities is that within 25 years, it is very likely that we will see practical solar-power satellites in orbit, exporting energy to 'Earth. Hence it is just a matter of time before the advanced technologies revolutionize space travel. In the following section the opportunities for developing commercial products and processes are explored.
125 A
7.1 Opportunities for developing commercial products and processes
The physical environment of outer space has many properties which are very different from the conditions found on earth. These environmental properties of space present interesting opportunities for developers of commercial products and processes. Some of the properties described below do not have obvious or immediate commercial applications, but in time all may be profitably exploited.
The most widely discussed property of space is weightlessness, often incorrectly described as the absence of gravity. Microgravity conditions can be simulated on earth for limited periods of time, 10 to 30 seconds in NASA's vacuum drop towers and on aircraft flying in parabolic arcs, and as long as 5 minutes on a suborbital sounding rocket. Microgravity eliminates many of the phenomenon we take for granted on earth and their absence creates commercial opportunities. For example, structures in space need not be strong enough to support their weight against the pull of gravity. Thus, very large, but very delicate structures can be built in space (such as antennas) that would collapse if built on earth. Similarly, the absence of hydrostatic pressure (the pressure gradient in a column of fluid caused by gravity) makes it possible to use float zone processing techniques on low surface tension materials. This cannot be done on earth because gravitational forces are stronger than the surface tension of most materials so an unsupported fluid column will bulge or sag during float zone processing. In addition, in
126 microgravity, the dominance of surface tension forces means that liquids naturally form into "perfect spheres." There are many potential commercial applications for perfectly uniform spheres such as ball bearings and latex calibration spheres.
Microgravity also eliminates thermal convection currents. On earth, hot air and hot liquids are lighter than cooler air and liquids so they rise, creating currents that disrupt the even mixing of solutions and lead to nonuniformities and defects especially in crystals. This effect can be virtually eliminated in space. Without convection currents, diffusion effects can be observed directly. Similarly, there can be neither sedimentation nor buoyancy effects in microgravity. Lighter materials will not separate from a mixture and - float on top of more dense materials so new alloys can be made in space that would not mix on earth. These new alloys may have commercially attractive properties. Conversely, solids will not precipitate out of a solution which permits the use of relatively weak, but precisely controlled forces such as electric fields to be used to purify or separate materials in solutions, leading to higher purity and greater production yields.
Materials in microgravity can be processed without containers through the use of acoustic levitation or electric or magnetic fields to hold them in position during processing. Containerless processing techniques have commercial potential for use with corrosive materials and materials which must be processed at high temperatures where contamination can be introduced from reactions with the walls of a container.
127 -- A
Space is a near perfect vacuum of enormous dimensions, of a quality and consistency difficult to attain on earth even with elaborate equipment. The exact level of the space vacuum depends on the altitude of the spacecraft and the level of solar flare activity. Although vacuum chambers can be built on earth, they are generally imperfect, and large, high vacuum chambers are very expensive. The space vacuum, and the ability to introduce any type of atmosphere at any desired pressure should facilitate many experiments and commercial processes. Some highly reactive materials that on earth require multiple processing steps in a vacuum or inert atmosphere, such as titanium alloys and aluminum/lithium alloys used in aerospace applications, could be fabricated with greater ease in space. The space vacuum also enables processing or experimentation with ultrahazardous materials to be conducted safely. Some controversial genetic biology experiments, for example, might be suited to development and testing in space. The presence of vacuum also facilitates hyper- velocity manufacturing processes since materials can be accelerated to enormous velocities without air resistance. Hyper-velocity processes might be used for preparing refractory facings on drill bits, ultra high pressure manufacturing, and possibly for removal of space debris.
Solar energy in space is available in unlimited amounts and the fuel is free. The potential of solar energy has only begun to be explored. Considering the number of terrestrial processes which require repeated heating and cooling steps, both of which consume
128 costly energy, the commercial value of free thermal energy is apparent. Charged particles from the sun, known as the solar wind, are trapped by earth's magnetic field in the Van Allen radiation belts which range 400 to 40,000 miles from earth. The ability to test products and processes, in high and reasonably consistent levels of hard radiation for applications such as biomedical research, or testing nuclear power equipment or military hardware, may eventually become a commercially viable business, especially since a comparable environment would be difficult and very hazardous to duplicate on earth.
Satellites eventually run out of fuel, break down and some components degrade over time. Repairs are desirable but difficult to accomplish because most satellites are in geosynchronous orbit which cannot be reached by the shuttle, and very few -are designed to be repaired in space in any event. The rescue of Westar VI and Palapa B-2, and the repair of the Solar Maximum Mission satellite demonstrated that repair and rescue are technically feasible, albeit complex and expensive. A commercial on orbit satellite servicing market is not likely to develop until the number of satellites in low earth orbits increases and the technological uncertainties decrease. However, the space insurance industry may be forced into advancing the development of this segment as a means of reducing their future losses, an important objective since industry losses total nearly $300 million since February 1984.
The lack of electric power is one of the most serious current constraints on conducting research, production and other commercial
129 space projects. The shuttle can only provide 4 to 6 kilowatts at present which is inadequate to serve the needs of all users. The continuing demand for increasing amounts of electric power suggests a future market may exist for an electric utility industry in space to service the needs of commercial manufacturing facilities and large laboratories such as the space station. . The flight of Senator Garn demonstrated that civilians can survive in space with relatively little special training as thus commecialisation of space tourism is possible as well.
There are also several possible uses of the concepts developed for space application for non-space applications. For example, the potential application of experience derived from Space Station to the clean room design and development are unlimited. Clean rooms or rooms that were the predecessors of modern day clean room can trace their beginning back to World War I days. At that time there was no "clean rooms" as we know of today. But there were controlled areas that performed similar functions. These controlled areas within factories and laboratories attempted to eliminate the gross contamination associated with manufacturing areas. This contamination, consisting of heavy dust-laden air, had caused seizure of small bearings and gears used in the first aircraft instruments. As a result, controlled assembly areas were built. By segregating the work areas from other manufacturing operations, and by providing a filtered air supply, contamination control was first effected by cleaning practices. With the beginning of the World War II period, better filtration systems were developed, air conditioning and room
130 pressurization were considered essential. Personnel protective clothing were added later, as were air showers and personnel cleaning equipment.
The present day clean rooms are a result of advancing technology in the many other engineering fields. This advancement is a twentieth-century discovery. Clean rooms produce many present day products of sophisticated design. The main use of clean rooms are in micro-electronics and semiconductor facilities, the prime concern is to keep manufactured components free from contamination by any airborne particles, and this is especially important as component details reach sub-micron level. Control of the factors in and about a product is a function of technological advancement in science. Once this technology was well developed it was adopted by medical science for the operating rooms.
The nature of work performed in an operating room on humans is similar in nature to work performed in clean rooms on equipment. Room decontamination functions are both necessary and vital to continued, successful clean room operation. The events leading to the development of operating rooms were initially paralleled by events leading up to the development of clean rooms. With greater emphasis being placed on miniaturization of products by the electronic age, however cleanliness requirements for some clean rooms exceed those for operating rooms. Techniques of workers in operating rooms and clean rooms are similar in that they are controlled. Hence it is quite evident that the experience gained from the Space Station, which has many similar characteristics as that of a
131 clean room, will be adopted for the advancement of clean room technology. This in turn will benefit in developing better operating rooms.
In our earlier discussions even though we have been discussing the development of the welding in space, there are several possible uses of these concepts for non-space applications as well. For example, there are a number of cases in which welding must be performed in locations where skilled human welders are not easily available. They include such cases as welding in deep sea for salvaging and repair of under sea structures, welding construction and repair of structures in Arctic and Antarctic regions, and welding repair of nuclear reactor components in radioactive environments.
The remote technology developed for space applications can be used, perhaps with some modifications for a variety of non space welding jobs which are currently very difficult or impossible to perform. Also, there are some welding jobs which are physically difficult to perform by human welding. In number of cases, such as pipings in a submarine or a boiler, structures are designed in such a way that human welding can perform welding for construction and repair. However, some of the welding jobs are very difficult to perform due to the physical size of the human. Small, light weight, integrated automatic welding systems developed for space application may be useful for various welding jobs, which must be performed in a small, confined space.
Finally, the Scientists know that we have to explore new frontiers in order to advance the sciences. Typically, their greatest
132 difficulty is convincing the research funders to support basic research, which often seems to have no practical application, even though such research in the past has usually led to breakthroughs that benefit us all on an everyday basis. It's ironic that many scientists-those who know the value of raw research-are critical of the Space Station, where so much fundamental experimentation could be conducted. The history of science and technology suggests that as soon as a new niche in the technological environment is found, practical engineers and inventors find totally unexpected ways to fill that niche. It was the study of the use of humble hot water that gave rise to the steam engine, which powered the Industrial Revolution. Returning to the economy, the benefits of space will be same or more than the research on microelectronics which has created employment and profits for -many. Also the Europeans and Japanese know that space technology has been one of the greatest spurs to American technology as a whole. So it is not surprising that both the Western Europeans and Japanese have offered to participate in the Space Station, to the tune of three billion dollars, to make sure they have access to the Station itself and to any associated technology. Therefore, in order to provide greatest spurs to the American technology and to take full advantage of the vast resources of space and its potential for the improvement of the human conditions, increase in research activities in advanced space technologies is needed immediately.
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chapter 8
SUMMARY
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chapter 8
SUMMARY
In this thesis, in the first three chapters the growing nature of space activities and NASA's plans for space exploration programmes in the next 30 years have been discussed in detail. The development and nature of space research over the years and the national space policy issues have been addressed as well. Due to their large size future construction of space structures and inter planetary vehicles will be carried out in space. Also due to the increased service life of the space structures there is an increased need of repair and maintenance work to be carried out in space. The space structures are exposed to radiation and bombardment by micrometeorites. Therefore, the need for immediate development of space welding technologies for construction of space structures that can withstand high gravitational forces have been discussed. The major advantages of using welding for reliable repair and maintenance of space structures, especially for the damaged structures containing human life have been elaborated.
Since in space applications different materials, different structures and different welding conditions are encountered the need to carry out extensive studies in welding in space and then develop welding technology suitable for space applications was emphasised. The main requirements of the welding technologies for space applications are stated. The welding methods cosidered for space welding and the advantages and limitations of these welding 135 processes and the present status of space welding R&D was discussed extensively. It was concluded that at present mainly due to resource constraints the research is focussed on electron beam welding with a view of short term benefits only. No single welding process will be sufficient to perform all the welding tasks in space. A single welding process can do certain welding jobs, but there are many other jobs which cannot be successfully performed or which can be more effectively performed by other processes.
In view of the trade-offs caused by the complex interactions of environmental effects, human factors, and particular application limitations, it could be prudent to develop several different promising and versatile welding systems to cover wide range of contingencies. Therefore, each of these welding alternatives must be analyzed and evaluated in terms of its value, cost and risk characteristics. The value of each welding alternative should be assessed in terms of the benefits that can be expected to result if it is chosen for development, and in terms of the regrets that can be suffered if it is not chosen. Also, we should note that the shift to a new technology may take a decade or more to complete, it is, therefore, crucial to anticipate and develop welding technologies for space activities relatively far in advance.
At present cost has become the most important issue in evaluating space R&D projects, but this will result in dangerous situations in future. One of the main reasons for this state of affairs is due to the reliance on the conventional financial evaluation techniques. Therefore, in our discussions we have compared and 136 A
contrasted the R&D expenditure and capital investment expenditures and also the need for the public sector to take a different approach to the evaluation of a R&D investment. We have also noted the complex nature of the evaluation of the R&D projects and the inherent bias of the traditional financial evaluation techniques against R&D projects. Because of the greater range of possible outcomes, R&D projects may present significant strategic implications. Also each stage of a R&D investment yields information, which reduces the initial uncertainty over the ultimate value of the project.
Therefore, the management of a space project can respond to new information and thereby continuously alter the investment commitment and the risk of the project. Thus, the management commitment to a project should not be assumed to be constant for all time. Projects should be regularly evaluated .and if it does not result in a desirable outcome, investment can be terminated. For example, in case of developing space welding technologies, presently we can carry out R&D for promising welding technologies and depending on the future development and needs we could always abandon or increase investment in a particular project. These factors are not easily accommodated within the conventional financial techniques, but they fit naturally within option valuation techniques and decision tree analysis. Application of option evaluation techniques and decision tree technique for this purpose was discussed elaborately. It is suggested to combine all these techniques in order to evaluate the various welding technologies.
137 We have also noted that due to the increased need for the funds as expenditure in space has increased, it will not be possible for the government to fund the entire space research. Hence there is an immediate need for NASA to embrace the principles and processes involved in strategic management and develop alternate strategies for generating funds for the space welding research. International co-operation, commercialisation of space and increased funding for university research have been extensively analysed as alternate strategies. We have also discussed the importance and benefits of developing space technologies for exploiting the unprecedented opportunities the space have to offer. Also the several possible uses of the concepts developed for space applications for non-space applications have been listed.
The exploration of space pose one of the largest technological and scientific challenges for mankind. Just by wishful thinking and intense desire alone we cannot accomplish space exploration. Also, the success of the space programs will largely depend on meeting the technological and scientific challenges. Therefore, the only way to sustain advancement in space technology is by producing the best technology. By sustained R&D efforts it will be possible to take complex and expensive technologies and simplify them to inexpensive and reliable technologies. Therefore, the space activities should not be biased toward the satisfaction of immediate needs. Moreover, we should learn lessons from the mistakes committed in case of Hubble Space Telescope. NASA was blamed for missing the mirror's flaw because of its fixation on cost and therefore it should 138 stop trading higher risks for lower costs and a long term view of the space activities should be pursued relentlessly.
139 chapter 9
REFERENCE AND BIBLIOGRAPHY
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