Proceeding of the 6th International Symposium on Artificial Intelligence and Robotics & Automation in Space: i-SAIRAS 2001, Canadian Space Agency, St-Hubert, Quebec, Canada, June 18-22, 2001.
The Mars Technology Program*
James A. Cutts, Samad A. Hayati, Donald Rapp and Chengchih Chu Jet Propulsion Laboratory California Institute of Technology, Pasadena, CA 91109 and Joeseph C. Parrish, David B. Lavery and Ramon P. DePaula National Aeronautics and Space Administration Washington, DC 20456 drapp@jpl.nasa.gov
Keywords: technological innovations.1 The most important of these is the ability to make a safe landing at any locality on Mars, technology, exploration, lander, rover, sample Mars. These technology innovations would be carried return, technology plan, technology infusion forward into the 2011 mission, which is planned to be a Abstract sample return mission. The Mars Technology Program (MTP) is a NASA-wide The enabling technologies for the proposed 2007 and technology development program managed by JPL. It is 2011 surface missions will be addressed in a Focused divided into a Focused Program and a Base Program. Technology Program that is tightly tied to proposed The Focused Program is tightly tied to proposed Mars Mars Program mission milestones. It involves time- Program mission milestones. It involves time-critical critical deliverables that must be developed in time for deliverables that must be developed in time for infusion infusion into the proposed Mars 2007 and Mars 2011 into the proposed Mars 2007 and Mars 2011 missions. missions. This program bridges the gap between This program bridges the gap between technology and technology and projects by vertically integrating the projects by vertically integrating the technology work technology work with pre-project development in a with pre-project development in a project-like project-like environment. The technology work includes environment with critical dates for technology infusion. validation and risk reduction through simulation, A Base Technology Program attacks higher risk/higher laboratory and field tests and the use of flight payoff technologies not in the critical path of missions. experiments when required. 1. Introduction In addition, a Base Technology Program will address enhancing technologies for missions proposed for 2007 The NASA Mars Exploration Program has plans to and 2011, critical capabilities for Scout/competitive and implement a series of ambitious missions with launches Orbiter missions, and capabilities for all missions every two years, culminating in a sample return mission beyond 2011. The Base Program stresses breakthrough with a launch date in 2011. Launches will alternate technology elements that are not in critical path of between Orbiters and Landers at each Mars launch missions. It will address technology needs that are less opportunity. Orbiters would be launched on 4-year mature and higher risk (and higher payoff) than those centers in 2001, 2005, 2009, …, and will be used as constituting the Focused Program. The Base Program telecommunication relay stations after they carry out includes collaborative programs with the Outer Planets their primary science missions. Landers would be Program, competitive elements, and leveraged launched on 4-year centers in 2003, 2007, 2011,…. technology programs with other funding sources. A series of Scout missions have been proposed for The Focused Technology Program and the Base launch on 4-year centers starting in 2007. These Technology constitute the elements of the Mars missions would be competed for by the science Technology Program (MTP) that is managed by JPL, community. It is possible that they might involve but which is carried out by the full NASA community. airborne vehicles, balloons or networks of small landers, The relationship of the Focused Technology Program but the strongest proposals will be funded regardless of and Base Technology Program to the suite of planned the approach. NASA Mars missions for the next decade is illustrated The 2003 Mars Exploration Rovers (MER) mission in Figure 1. includes two rovers that are far more capable than the Pathfinder rover. The proposed 2007 Smart Lander mission would introduce a number of significant
Mars Express
Base Program ¥ Breakthrough technologies ¥ Broad impact ¥ Support Scouts ¥ Includes collaboration with other sponsors Focused Program ¥ Enable MSL and MSR ¥ Include risk reduction and validation ¥ Run like a project
Figure 1. Contributions of the Focused and Base Programs to Mars missions.
resulting in a landing error ellipse ranging from 100 km In order to develop capabilities for these missions and cross range to 300 km along the downrange vector. The beyond, the NASA Mars Technology Program is being payload mass that can be delivered using existing or implemented under JPL leadership. This Program’s goal anticipated launch vehicles with this system is limited to is to develop and infuse key technologies needed to ~ 70 kg. enable proposed future Mars missions. In this paper, a synopsis of the plan for implementing the Mars Precision landing reduces the risk of encountering Technology Program is provided. hazardous areas such as large craters and steep canyons at any given region of Mars where it is desired to land. 2. Focused Technology Program Our goal is to develop new technology to reduce the 2.1 Mars 2007 Smart Lander landing error ellipse to smaller than 3 x 10 km. In One of the main goals is to develop the capability to addition the payload mass will be raised to ~ 300 kg. To land safely near any chosen site (including higher achieve this goal, each step of the EDL process is elevations) in order to provide a global access to Mars. upgraded with new technology. Figure 2 illustrates the To achieve this ability to land safely at any locality on steps involved in precision EDL. Each step is being Mars, the entire process of entry, descent and landing developed with advanced technology, with systems was reviewed and innovations are planned to provide integration used to assure that all the pieces fit together. the needed capabilities. To achieve this goal, three complementary technologies The present state of the art for EDL on Mars utilizes are being developed: radio-based approach navigation, no control of the lift • Precision landing vector during entry, a single stage parachute, and hazard tolerance only to the extent that either airbags or landing • Hazard avoidance struts are utilized. There is no hazard • Robust landing detection/avoidance capability. Variants of this approach were used on Viking and Pathfinder and will be used on the Mars 2003 mission. The errors in approach navigation propagate through the trajectory,
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Deploy hypersonic chute @ 10-12 km
Jettison backshell & hyper chute (7-9 km)
Deploy subsonic chute; jettison heat shield (7-9 km) Generate terrain map with RADAR; compute landing area (7-9 km) Generate terrain map with LIDAR and RADAR; Designate safe landing area (1.5 km) Jettison subsonic chute, ignite descent engines (.5-.7 km) 30- 45 sec to touchdown
Continue computing reachable landing site ellipse. Compute desired acceleration to achieve touchdown condition Designate a new landing site, if available, to avoid hazards
Descend to 15 m above landing site
Descend at constant acceleration
Shut engine 1 m above surface
Figure 2. Schematic steps involved in precision descent and landing.
lander to a safe landing area. A RADAR sensing system 2.1.1 Precision Landing for 0-7 km altitudes will be developed to generate initial A new optical navigation camera is being developed to terrain maps and create initial estimates of the landing use the Martian moons Phobos and Deimos as reference area at ~ 7 km altitude. When the capsule descends to ~ targets for precise entry. A lifting entry vehicle is being 1.5 km, LIDAR is used to augment the RADAR terrain developed with L/D ~ 0.25 that is capable of actively maps, and alternate landing sites are designated if guiding itself from entry to parachute deployment hazards are detected. Field tests will be conducted with despite uncertainties in the entry conditions, rocket sled and helicopter test platforms to validate atmospheric density profile, winds and aerodynamic these technologies. performance (Figure 3). A two-stage parachute system will be developed with the subsonic parachute having the potential for para-guidance. Improved descent propulsion will be achieved by recapturing Viking technology with new miniaturized components. 2.1.2 Hazard Avoidance Hazard avoidance provides an “eyes wide open” capability at landing. The overall process is illustrated in Figure 2. This makes it possible to make last-minute adjustments to landing location to avoid large craters, large rocks and steep local slopes. (Figure 4) The MTP will develop an integrated terminal guidance, navigation and control system that predicts the descent flight path after the subsonic parachute is deployed, detects hazards such as rocks and slopes using active sensors, and after jettisoning the parachute, steers the Figure 3. Schematic of Controlled Entry
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2.1.3 Robust Landing Once landing is committed to, this technology makes it possible to tolerate the unexpected or provide resilience to failures in either precision landing or hazard avoidance systems (Figures 5 and 6). Two approaches are under study, one involving airbags and the other a pallet system. A down-select to choose the optimum approach is expected by the end of FY2001. 2.1.4 Long Life Surface Power There are two potential approaches for surface power on Mars: radioisotope power and solar photovoltaic power. The Viking missions used small radioisotope thermoelectric generators (RTGs) as power sources. The Mars Pathfinder mission utilized solar photovoltaic power. Each of these approaches has advantages and disadvantages, with significant implications for mission Figure 4. Schematic Hazard Avoidance design. Solar power may be feasible for some surface missions on Mars. Surface missions powered by photovoltaics carry out most operations during a ~ 7 hour period centered on solar noon, and use batteries to provide survival levels of power overnight. The feasible duration of Mars surface missions powered by solar energy depends on: • latitude and season • dust accumulation on photovoltaic arrays • battery life Dust accumulation is expected to be the major impediment to long life solar powered missions. A number of potential methods for dust mitigation are under consideration by the MTP including rollable Figure 5. Schematic Pallet Lander transparent covers, blowers, wipers, etc. Tests on several approaches will be conducted in simulated Mars environments. The MTP is also planning to develop photovoltaic cells optimized for the spectrum on the Mars surface that is depleted at shorter wavelengths. Battery technology is a critical technology for Mars surface missions to provide routine overnight survival, and survival during occasional dust storms. The MTP includes technology to develop batteries that can produce more cycles at lower temperatures. Some future Mars missions will require radioisotope power. Radioisotope power has a number of advantages over solar power: • Continuous power source - no overnight survival mode - batteries for load balancing, not survival • Impervious to dust accumulation, dust storms, shadows from canyon walls, etc. • Virtually unlimited lifetime; independent of latitude Figure 6. Schematic Air Bag Lander However, there are also disadvantages to radioisotope power:
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Need to reject excess heat from aeroshell during cruise, system will be designed, built and tested with a sub- entry, descent and landing. orbital flight. (Figure 7) Radioisotope power is not easily scalable, whereas photovoltaic power is easily scalable. Radioisotope power is much heavier than photovoltaic power when compared at peak power rates (4.5 We/kg vs. >50 We/kg). Some radioisotope power systems are expensive, and availability of radioisotopes is uncertain. In order to greatly reduce the amount of heat that must be rejected during cruise, entry, descent and landing, and to greatly reduce the amount of radioisotopes needed at any power level, the MTP is providing some of the funds needed for further long-term development of the highly efficient Stirling converter. 2.2 Mars 2011 Sample Return Although, the ultimate architecture of the Mars 2011 Sample Return mission is still not settled, the pivotal capabilities that must be developed to enable any Mars Figure 7. Schematic Mars Ascent Vehicle Sample Return mission are understood. These capabilities include those developed for the Mars 2007 Smart Lander, as well as technology specific to sample 2.2.3 Rendezvous and Sample Capture return. The Mars Technology Program will develop needed technology for the proposed Mars 2011 Sample An autonomous sample rendezvous and capture system Return mission, and where aspects of the mission must be developed with the ability to autonomously remain undecided, will provide technical data and locate, track and capture a small sample canister in Mars analysis to assist the Mars Program Systems orbit or deep space for return to Earth. A LIDAR sensor Engineering Team (MPSET) to make these decisions. is under development for utilization in the autonomous Sample return technology is divided into the following sample rendezvous and capture system. five elements. 2.2.4 Sample Containment & Earth Return 2.2.1 Forward Planetary Protection In order to carry out a sample return mission, Forward planetary protection will protect against technology must be developed to provide secure transporting Earth-organisms to Mars that could (1) containment of the sample, while preventing any contaminate the planet, or (2) which could appear in possible Mars organisms from being inadvertently returned samples from Mars, or (3) which could released into the Earth’s environment. In order to interfere with in situ instruments attempting to detect accomplish this, the chain of contact from Mars to Earth life on Mars. Technology will be developed to produce must first be broken without breaking the seal on the a robust cleaning method. This will be accompanied by container. Two complementary techniques for a rapid method for bio-burden validation. It is hoped to sterilizing exposed sealing plane edges in the airlock use a H2O2 plasma sterilization scheme to kill extreme break-the-chain concept are being evaluated. One uses microbes on hardware surfaces. Cleaning and fluorine gas to sterilize the exposed Martian surfaces. sterilization methods will be validated by tests on The other uses explosive welding to sterilize and seal hardware subassemblies. the exposed surfaces. Further work will bring the fluorine technology to NASA Technology readiness 2.2.2 Mars Ascent Vehicle (MAV) Level (TRL) 6 by the end of 2003 and the pyro-weld 2 The Mars Ascent Vehicle must transfer clean samples technology to TRL 5 by the end of 2003. In addition to from the surface of Mars to an Earth Return Vehicle breaking the chain of contact, other technologies such as located either Mars orbit or on an Earth-bound micrometeorite protection and containerization integrity trajectory. The various alternatives for a MAV rocket are being developed. approach (solid, liquid, hybrid, cryo, etc.) are being compared by systems analysis. A down-select to a single approach will be made during FY2001. This
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CY 01 02 03 04 05 06 07 08 09 10 11
Mars 2007 PMSR PDR Launch Smart Lander
PMSR Launch Mars 2011 PDR Sample MSR Concept Selection Return
Mars System Studies Lander Technology TRL 4-5 TRL 6 MSR Technology TRL 5-6 TRL >6
Figure 8. Schedules for infusion of Mars focused technology into the Mars 2007 Smart Lander and the Mars 2011 Sample Return (MSR) missions and the Earth Entry mode where the options are Direct 2.2.5 Returned Sample Handling Entry and Earth Orbit Rendezvous. Key trades that will After the samples are returned to Earth, they must be influence these decisions will be conducted as part of secured to prevent inadvertent release of possible Mars the Mars Program Systems Engineering Team (MPSET) organisms, and the samples must be protected from activities planned in FY’01. The decisions will impact contamination by Earth organisms. Returned sample all elements of the MSR Focused Technology Program handling technology includes cleaning and sterilization at some level. At the same time, the state of technology processes, cold sample storage and processing, and life- advances and projections of advances in these detection technology. technologies over the next several years, will influence the decisions to be made by mission planners by 2.3 Mission Infusion Schedule defining what appears to be feasible within appropriate The schedule for development of Mars focused time spans. Thus there is an ongoing symbiotic relation technology is primarily driven by the project schedules between Mars Sample Return mission planning and for the Mars 2007 Smart Lander and the Mars 2011 advances in sample return technology. Sample Return (MSR) missions as shown in Figure 8. The schedules for validation and infusion of various The two key dates for technology infusion into the MSR technologies are shown in Figure 9. projects are the Preliminary Mission Systems Review (PMSR) and the Preliminary Design Review (PDR). 3. Base Technology Program The maturity of a technology is assessed using the The Base Technology Program will address enhancing NASA Technology Readiness Level (TRL) scale. technologies for missions in 2007 and 2011, critical Technologies at NASA TRL 5-6 at PMSR will capabilities for Scout/competitive and Orbiter missions, influence the mission concept, and technologies at TRL and capabilities for all missions beyond 2011. The Base ≥6 at the time of PDR are candidates for infusion into Program stresses breakthrough technologies and is less the baseline project design. In addition, an early tightly coupled to mission milestones than the Focused preliminary MSR concept selection will be made at the Program. It will address technology needs that are less time when the Smart Lander has its PMSR, in order to mature and higher risk (and higher payoff) than those promote commonality between the two missions. constituting the Focused Program. The Base Program includes collaborative programs with Deep Space Several key decisions on the MSR architecture will Systems, competitive elements, and leveraged greatly influence the technology that will be developed technology programs with other funding sources. The in FY’02 and later. These include a decision on the Base Program includes enhancing technologies that are Earth Return mode where the options are Direct Return, not in critical path of missions. Deep Space Rendezvous and Mars Orbit Rendezvous
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CY 01 02 03 04 05 06 07 08 09 10 11
MARS SAMPLE RETURN SRR PDR CDR Launch
Focused Technology Suborbital Demo(*) MARS ASCENT VEHICLE TRL=7 SRR PDR CDR Launch Focused Technology RENDEZVOUS AND SAMPLE CAPTURE
SRR PDR CDR Launch Earth Orbit Demo
CDR Launch Mars Orbit Demo (CNES 07 Orbiter) TRL=7
FORWARD PLANETARY PROTECTION TRL=6
SRR PDR CDR Launch MARS 2007 SMART LANDER
RETURNED SAMPLE HANDLING TRL=6
(*) Needed if unguided Flight Project Focused Flight Technology solid is selected technology Demo Selection
Figure 9. Schedule for Infusion of MSR technologies into Mars Sample Return Mission
Earth’s atmosphere at around 35 km. These platforms 3.1 Regional Mobility and Subsurface Access provide access to Mars that is intermediate in scale Improved rover autonomy is being developed to enable between orbiters, which can view large areas with safe navigation as well as autonomous science relatively low resolution, and rovers which can examine operations for Mars surface missions including the 2003 relatively smaller areas with high resolution. Mars surface mission. The Base Program is developing Inflatable rovers may enable packaging into small technology for the on-board capability to negotiate spacecraft to provide alternatives for all surface relatively long distances (100 to 200 m/day) without missions. Several alternate designs will be built and supervision from the Earth during traverses from one field-tested. exploration site to another. The time delay inherent to Earth-Mars communications makes it impractical to A comprehensive control architecture is being carry out long traverses with Earth supervision. developed for autonomous rovers that capture the state Technology is also under development to reduce the of the art in robotics and autonomy software. This number of uplinks and downlinks required in making scientific observations. New instrument concepts will be integrated with rover platforms. These technologies will be fully tested and validated with full-scale remote terrestrial field trials in simulated Mars terrain, including simulated science operations. (Figure 10) Studies are being conducted on mechanical scaling of rovers to determine how capabilities to negotiate terrain and characteristics (mass, power, turning capability, ...) vary with scale. Large size vehicles may be needed for carrying heavier payloads over long traverses on rough terrain. A more speculative area with potentially high payoff for Scout missions is lightweight aerial platforms such as balloons and aircraft. Technology is being developed for deploying and inflating super-pressure balloons and Figure 10. Test rover in simulated Mars developing aircraft designs capable of flight in the testbed tenuous Mars atmosphere which has the density of the
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system is distinguished by its layered structure using object-oriented hierarchies. 3.2 Science Instruments The Base Program will develop the capabilities for The Mars Instrument Development Program (MIDP) autonomous access to the subsurface of Mars via provides funds via competitive opportunity to advance drilling or moles within limited power and mass the maturity of unique in-situ instruments to allocations (Figure 11). The initial goal is to achieve characterize the geology and environment of Mars, as depths of 10-20 m; the intermediate goal is 200-400 m; well as for life detection (past or present). A number of and the long-term goal is to achieve depths of up to 2 instruments at NASA Technology Readiness Level ~ 3 km. Ultrasonic drilling devices are being developed. In must be advanced to at least TRL ~ 6 in order to be addition, a competitive opportunity for industry is also candidates for inclusion in future missions. The goal of being implemented to explore a wide range of the MIDP Program is to identify the most promising alternatives. Funding will begin during FY 2001. candidate instruments at TRL ~3 and advance them to TRL ~ 6. Several instruments are presently under development as a result of an NRA issued in 1998 and a new NRA will be issued in 2001. 3.3 Non-Earth-Centric Life Detection Non-Earth-centric life detection is concerned with definition of life in non Earth-centric terms, definition of appropriate bio-signatures, development of data mining approaches, and demonstration of specific approaches and instruments for life detection. 3.4 Transportation and Orbit Insertion The Base Technology Program is exploring three Figure 11. Rover-based drilling system alternative (and to some extent complementary) approaches for achieving higher propulsive efficiency for Mars missions. A system is being developed for automated science operations and data retrieval and visualization. This will 3.4.1 Solar Electric Propulsion include development of a rover operations environment Solar electric propulsion (SEP) imparts a much higher that (1) enables full participation in mission operations exhaust velocity to ions ejected by an engine than is from multiple Internet-based sites, (2) reduces sequence possible with chemical propulsion. As a result, higher generation time by providing collaborative visualization accelerations of a payload is possible with electric and target selection, and concurrent sequence building propulsion. However, the thrust is lower in SEP and by distributed users, and (3) reduces time necessary to therefore it takes considerably more time to achieve this understand planetary terrain and verification of planned ultimate acceleration, and SEP does not function well in sequences by providing a high-fidelity immersive gravitational fields. The Base Technology Program will visualization environment. increase the maximum specific impulse, power level and thrust obtainable through solar electric propulsion A Science Collaboration Testbed (SCT) will use test (Figure 12). This technology has the potential to provide data, mission plans, and sequence designs to create a much higher payload fraction as compared to chemical simulated mission scenarios (SMS), and replay rover propulsion, a reduction in launch vehicle costs, and down-links to verify, validate, integrate, test and global access to Mars. In addition, analysis will be used evaluate new science collaboration tools and models for to optimize the use of SEP in mission trajectories. This landed operations. This will provide prototype virtual will include: (1) developing low-thrust trajectory design mission design, planning, and operations’ interface tools to increase the range of mission types that can be using multi-resolution Mars images, topography, optimized for low-thrust interplanetary trajectories, (2) spectral data, spacecraft position, and instrument making improvements on the present very limited and pointing data. This technology will be adapted for Mars cumbersome capability to design low-thrust ’03 Landing Site selections and Mars ’05 image target interplanetary trajectories with higher fidelity models, selections. and (3) making improvements on the present simple, analytic model for determining a crude estimate of the time and propellant required to capture to or escape from a circular orbit around a planet.
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order to enable high-speed transmission of orbital remote sensing data as well as data relayed from surface assets. The approach is to achieve significant increase in Equivalent Isotropic Radiated Power (EIRP) through: • Higher-power transmitters • Increased aperture (fixed and deployable) • Near-term transition to Ka-band • A flight demo in support of longer-term transition to optical communication 3.5.2 Proximity Link Communications Figure 12. Electric propulsion thruster Proximity link relay communications capabilities are under development to enable increased data return and increased connectivity with future Mars spacecraft, landers, rovers, gliders, etc. The approach involves 3.4.2 Advanced Chemical Propulsion communicating data from assets in the Mars Chemical propulsion systems will be developed with environment at UHF (~800 MHz) to an orbiter equipped lower system mass and higher specific impulse. Some with a powerful trunk line capability. of the technology will be transferable to electric These systems will be radiation tolerant/hardened and propulsion feed systems. Several specific goals include: reconfigurable. • 50% mass reduction in titanium propellant tank. 3.6 Advanced Entry, Descent and Landing • Hydrazine mN thruster - 70% mass reduction, 40- Advanced entry, descent and landing (EDL) is the fold reduction in volume, factor of 100 reduction in logical extension of the EDL development in the thrust. Focused Technology Program, and it aims to develop an • 90% mass reduction in transducers. advanced entry, descent and landing system that provides "pinpoint" delivery (10-100 m accuracy), much • 5 lbf biprop thrusters with 15 sec Isp gain allowing more capable hazard avoidance, and a higher payload 60% mass reduction compared to the state of the delivery (>500 kg). (This technology also looks beyond art. 2011 and may also support Scout activities). Activities 3.4.3 Aerocapture include: Aerocapture has the potential to eliminate the need for • Develop and verify an architecture for employing large quantities of propellant to decelerate a spacecraft multiple sensors for hazard avoidance in landing on when entering a planetary orbit. The challenge is to find Mars. suitable lightweight protective shells to protect the • Develop the ability to deploy and inflate balloon spacecraft from the intense heat generated during the and ballute designs through advanced modeling and aerocapture process. The Base Technology Program analysis of inflatable structures and dynamics. will quantify the benefits and disadvantages of aeroshells and ballutes in terms of mass, aero- • Develop a breadboard for a next-generation Mars thermodynamic loads, and trajectory robustness, and LIDAR aimed at increasing the sensor range to the will then advance the better approach (ballutes or Mars surface aeroshells) to TRL = 6 as preparation for a flight • Use supercomputing based simulation to provide experiment/demonstration. terrain generation, site modeling and visualization 3.5 Telecommunication and Navigation support for Mars EDL activities. Telecommunications advances are needed for • Determine the feasibility of orbiting beacon communication between Earth and Mars and among navigation for precision landing and develop orbital assests and landers, rovers, and aerial platforms guidance algorithms incorporating orbiting beacon at Mars. navigation data. 3.5.1 Deep Space Communications • Develop and test an advanced guidance concept for hypersonic entry and atmospheric flight to increase The goal is to increase the data return capability on the robustness of precision landing schemes to errors “trunk line” deep space link between Mars and Earth in and unceratinties.
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• Develop a fast, robust passive imaging-based hazard detection/avoidance scheme for safe landing on Mars. TRL Accomplishment 4. Conclusions The Mars Technology Program is divided into a 1-2 Concept and application are formulated. Basic Focused Program and a Base Program. The Focused phenomena are observed in a laboratory Program is tightly tied to Mars Program mission environment. milestones. It involves time-critical deliverables that 3 Critical functions are tested in a laboratory must be developed in time for infusion into the Mars environment of breadboard configuration to 2007 and Mars 2011 missions. This program transcends validate proof-of-concept’s potential the usual gulf between technology and projects by performance and lifetime. vertically integrating the technology work with pre- 4 A breadboard system (or at least the major project development in a project-like environment with components of the system) are tested in the critical dates for technology infusion. It will primarily laboratory and verify that components will address developing technology to enable safe landing work together effectively in a system. At this anywhere on Mars, long life surface power, and level, preliminary analytical and enabling sample return technologies. experimentally efforts are made to calculate lifetime performance of critical components. In addition, a Mars Base Technology Program attacks 5 A realistic breadboard portion of the system is higher risk/higher payoff technologies not in the critical thoroughly tested in a relevant environment path of missions. The Base Program will also support that demonstrates the flight system design. technologies that may be enabling for Scout missions. Lifetime performance predictions of critical Further information can be found at the web site: components are validated with accelerated tests. http://stargate.jpl.nasa.gov/devel/redplanet/technology/. 6 System engineering model with approximate “form fit and function” of a flight systems or prototype demonstration tested in a relevant * Acknowledgement: environment on ground or in space. System lifetime performance prediction validated The research described in this paper was carried out by based on accelerated life testing of components the Jet Propulsion Laboratory, California Institute of and subsystems. Technology, under a contract with the National Aeronautics and Space Administration. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer or otherwise, does not constitute or imply its endorsement by the United States Government or the Jet Propulsion Laboratory, California Institute of Technology. 1 "Second Generation Landed Missions," J. Graf, et al., IEEE Conference in Big Sky, Montana, , Paper No. 0- 7803-6599-2/01, March 12, 2001. 2 The NASA TRL scale is used as a measure of the relative maturity of a technology. A technology must reach NASA TRL 6 by spacecraft preliminary design review (PDR) in order to be adopted by a space project.
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