DOCSLIB.ORG

Overview of the ASPIRE Project June 12-16, 2017 - the Hague, NL

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Overview of the ASPIRE Project June 12-16, 2017 - the Hague, NL 14th International Planetary Probes Workshop Overview of the ASPIRE Project June 12-16, 2017 - The Hague, NL. Clara O’Farrell, Ian Clark & Mark Adler Jet Propulsion Laboratory, California Institute of Technology © 2017 California Institute of Technology. Government Sponsorship Acknowledged. ASPIRE Disk-Gap-Band (DGB) Parachute Heritage MSL (2012) MER (2004) • Developed in the 60s & 70s Viking (1974) for Viking – High Altitude Testing – Wind Tunnel Testing – Low Altitude Drop • Successfully used on 5 Mars missions – Leveraged Viking development Viking BLDT Test MER Drop Test MSL Wind Tunnel Test Image credit: mars.nasa.gov June 12-16, 2017 14th International Planetary Probes Workshop 2 jpl.nasa.gov Aerospace in recent DGB designs: Clark & Tanner, IEEE Broadcloth stress Conference Paper 2466 (2017): (per unit length) Broadcloth ultimate load estimated by treating the disk as a pressure vessel: Disk diameter have been eroding jpl.nasa.gov 3 180 Actual Flight Load ASPIRE 160 Parachute Design Load Broadcloth Ultimate Load DGB Heritage & Design Margins Strength margins may 140 f b l 120 • 3 0 1 x , 100 d a o L e 80 t u h c a r 60 a P 40 parachutes well below those achieved in supersonic tests 20 stresses seen in subsonic testing may not bound the 14th International Planetary Probes Workshop -Densityringsail Supersonic0 Decelerators Project saw failures of two 9. 19 12 12 12 S V V V V P S O P M 1 . P ik ik ik ik at pi p ho S m 7 2 2 2 E i i i i h r p e L m m m m D n n n n f it o n M - g g g g in rt i 1 M M M M II A A I I d u x . 1 1 2 3 V V I e n 5 . r it 6 5 9 7 3 - - y 9 1 2 1 1 4 The Low • supersonic LDSD experience • stresses seen in supersonic testing, at least for some parachutes -16, 2017 June 12 ASPIRE The ASPIRE Project • Advanced Supersonic Parachute Inflation Research Experiments Project established to investigate the physics of supersonic DGB inflation • DGBs to be tested on sounding rocket flights out of Wallops Flight Facility (WFF) starting summer 2017 • Expose two candidate M2020 parachute designs to a supersonic inflation environment Payload Sep Mortar Fire L+104 s L+160-170 s Alt: ~50 km Alt: 39-45 km Mach: 1.8 q∞: 360-820 Pa Line Stretch Mach: 1.65-1.9 MF+~1 s q∞: 400-930 Pa Mach: 1.68 2nd stage Brant burnout L+35.5 s Alt: 16.7 km Peak Load Mach: 3.2 MF+~2 s q∞: 400-900 Pa Mach: 1.64 2nd stage Brant Ignition L+8.0 s Alt: 1.5 km Nosecone Jettison Alt: 3 km 1st stage Terrier burnout L+5.2 s Alt: 0.7 km WFF Launch Site Splashdown Atlantic Ocean L + ~30 min ~60 -100 km jpl.nasa.gov ASPIRE Test Architecture st a l l a • Rail-launched Terrier Black Brant Ballast b (jettisoned before • Spin-stabilized at 4 Hz splashdown) • Yo-yo de-spin after 2nd stage Payload (7.54 m) burnout Buoyancy Aid (foam) & m a • Mortar-deployed full-scale DGB o electronics f • Cold gas ACS active from payload separation to before mortar fire Telemetry (sealed) cs i n o 17. 7 m vi • Recovery aids: a – Foam provides buoyancy – Nosecone ballast (for aerodynamic 2nd Stage Black Attitude Control Brant IX stability) is jettisoned before System S AC BLACK BLACK BRANT (5.89 m) splashdown m a o f • Payload mass: / Experiment r a – Launch: 1268 kg rt mo / e – Post-separation: 1157 kg t u ch – Splashdown: 128 kg ra a 1st Stage Terrier Aft transition & p (4.3 m) separation Hardware TERRIER TERRIER r e De-spin hardware t p a d a June 12-16, 2017 14th International Planetary Probes Workshop 5 jpl.nasa.gov ASPIRE Parachutes Test two full-scale mortar-deployed DGBs: • MSL built-to-print • Strengthened version of MSL DGB with a stronger broadcloth MSL built-to-print Strengthened D0 21.35 m 21.45 m SL length 37.0 m (1.73 D0) 36.44 m (1.70 D0) Riser length 7.05 m 7.78 m Geometric Porosity 12.5% 12.5% No. of gores 80 80 SL line material 2100 lb Technora 3500 lb Technora Band fabric PIA-C-7020 Type I Custom nylon Heathcoat Ltd. Disk fabric PIA-C-7020 Type I (skirt)/Polyester 8860 (crown) (1.86 yd/oz, 100 lbf/in) Radials 2100 lb Technora 3500 lb Technora Mass 49.8 kg 75.4 kg Fabric permeability 100 cfm 90 cfm June 12-16, 2017 14th International Planetary Probes Workshop 6 jpl.nasa.gov ASPIRE Schedule & Test Matrix • Top Level Objectives • Expose two candidate designs to a supersonic inflation environment • Acquire data sufficient to characterize the flight environment, loads, and performance of the parachute • Baseline strategy requires four successful flights: Parachute Load Purpose Target date SR01 35 klbf Ensure test approach doesn’t introduce Built-to-print Sept. 19, 2017 (MSL @ Mars) new parameters. SR02 Ensure strengthened design survives 35 klbf Strengthened MSL load; calibrate targeting for next two Nov. 1, 2017 (MSL @ Mars) flights SR03 Strengthened 70 klbf Strength test of new design Dec. 19, 2017 SR04 Strengthened 70 klbf Address testing variability Feb. 4, 2018 SR05 TBD SR06 • Six flights planned to provide margin on four required tests June 12-16, 2017 14th International Planetary Probes Workshop 7 jpl.nasa.gov ASPIRE Instrumentation Experiment section: 3x load pins at triple- Instrument Ring: bridle attachments Parachute Pack Mortar Tube Instrument Ring 3x HS/HR cameras 3x SitVid cameras for stereo imaging • Additional on-board instrumentation: – GLN-MAC IMU – GPS – C-band transponder (radar tracking) • Meteorological instrumentation: – 3x meteorological balloons carrying Radiosondes: temperature, density, winds to 35 km – 2x SuperLoki rockets w/inflatable ROBIN spheres: temperature, density, winds for 30 - 60km • Allow reconstruction of: – Parachute loads – Conditions at parachute deploy (Mach, dynamic pressure, angle of attack) – Parachute shape & position • See B. Sonneveldt et al “Instrumentation and Reconstruction for the ASPIRE Supersonic Parachute Test Campaign” (poster) June 12-16, 2017 14th International Planetary Probes Workshop 8 jpl.nasa.gov ASPIRE ASPIRE Data Products & Success Criteria • Data products: • Payload trajectory from separation until mortar fire + 60 sec: position, velocity, acceleration, attitudes rates • Payload aerodynamic states trajectory from separation until mortar fire + 60 sec: Mach, dynamic pressure, angles of attack, sideslip • Synchronized parachute load history • Synchronized HS/HR camera imagery • Parachute inspection report • Minimum success criteria • Deliver the experiment to the required test conditions. • Acquire, transmit, and record the required experiment data. • Recover the experiment section without recovery induced damage to the data. • Recover sufficient data to determine the parachute peak load, assuming proper payload functionality. • Comprehensives success criteria • Recover the parachute assembly (that remains attached to the experiment section) without recovery-induced damage. June 12-16, 2017 14th International Planetary Probes Workshop 9 jpl.nasa.gov ASPIRE Acknowledgments The authors are grateful for the many contributions from the ASPIRE team. Project Manager: Tom Randolph Deputy Project Manager: Mike Hughes Project Manager Emeritus: Mark Adler Principal Investigator: Ian Clark Parachute CogE: Chris Tanner Flight Performance (JPL): Mark Ivanov Flight Performance (LaRC): Eric Queen Aerosciences: Suman Muppidi Sounding Rocket Lead: Brian Hall NSROC Mission Manager: Jay Scott WFF Range Lead: Dave Wilcox This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. June 12-16, 2017 14th International Planetary Probes Workshop 10 jpl.nasa.gov jpl.nasa.gov.
Load more

Recommended publications
  • Concepts and Approaches for Mars Exploration1
    June 24, 2012 Concepts and Approaches for Mars Exploration1 ‐ Report of a Workshop at LPI, June 12‐14, 2012 – Stephen Mackwell2 (LPI) Michael Amato (NASA Goddard), Bobby Braun (Georgia Institute of Technology), Steve Clifford (LPI), John Connolly (NASA Johnson), Marcello Coradini (ESA), Bethany Ehlmann (Caltech), Vicky Hamilton (SwRI), John Karcz (NASA Ames), Chris McKay (NASA Ames), Michael Meyer (NASA HQ), Brian Mulac (NASA Marshall), Doug Stetson (SSECG), Dale Thomas (NASA Marshall), and Jorge Vago (ESA) Executive Summary Recent deep cuts in the budget for Mars exploration at NASA necessitate a reconsideration of the Mars robotic exploration program within NASA’s Science Mission Directorate (SMD), especially in light of overlapping requirements with future planning for human missions to the Mars environment. As part of that reconsideration, a workshop on “Concepts and Approaches for Mars Exploration” was held at the USRA Lunar and Planetary Institute in Houston, TX, on June 12‐14, 2012. Details of the meeting, including abstracts, video recordings of all sessions, and plenary presentations, can be found at http://www.lpi.usra.edu/meetings/marsconcepts2012/. Participation in the workshop included scientists, engineers, and graduate students from academia, NASA Centers, Federal Laboratories, industry, and international partner organizations. Attendance was limited to 185 participants in order to facilitate open discussion of the critical issues for Mars exploration in the coming decades. As 390 abstracts were submitted by individuals interested in participating in the workshop, the Workshop Planning Team carefully selected a subset of the abstracts for presentation based on their appropriateness to the workshop goals, and ensuring that a broad diverse suite of concepts and ideas was presented.
    [Show full text]
  • Zlib Home Site
    zlib Home Site http://zlib.net/ A Massively Spiffy Yet Delicately Unobtrusive Compression Library (Also Free, Not to Mention Unencumbered by Patents) (Not Related to the Linux zlibc Compressing File-I/O Library) Welcome to the zlib home page, web pages originally created by Greg Roelofs and maintained by Mark Adler . If this page seems suspiciously similar to the PNG Home Page , rest assured that the similarity is completely coincidental. No, really. zlib was written by Jean-loup Gailly (compression) and Mark Adler (decompression). Current release: zlib 1.2.6 January 29, 2012 Version 1.2.6 has many changes over 1.2.5, including these improvements: gzread() can now read a file that is being written concurrently gzgetc() is now a macro for increased speed Added a 'T' option to gzopen() for transparent writing (no compression) Added deflatePending() to return the amount of pending output Allow deflateSetDictionary() and inflateSetDictionary() at any time in raw mode deflatePrime() can now insert bits in the middle of the stream ./configure now creates a configure.log file with all of the results Added a ./configure --solo option to compile zlib with no dependency on any libraries Fixed a problem with large file support macros Fixed a bug in contrib/puff Many portability improvements You can also look at the complete Change Log . Version 1.2.5 fixes bugs in gzseek() and gzeof() that were present in version 1.2.4 (March 2010). All users are encouraged to upgrade immediately. Version 1.2.4 has many changes over 1.2.3, including these improvements:
    [Show full text]
  • Arthur C. Clarke 2001: a Space Odyssey
    Volume 33, Issue 2 AIAAAIAA HoustonHouston SectionSection www.aiaa-houston.orgwww.aiaa-houston.org April 2008 Arthur C. Clarke 1917 - 2008 2001: A Space Odyssey - 40 Years Later Yesterday’s Tomorrow Artwork by Jon C. Rogers and Pat Rawlings AIAA Houston Horizons April 2008 Page 1 April 2008 T A B L E O F C O N T E N T S From the Acting Editor 3 HOUSTON Chair’s Corner 4 2001: A Space Odyssey - 40 Years Later: Yesterday’s Tomorrow 5 Horizons is a quarterly publication of the Houston section of the American Institute of Aeronautics and Astronautics. International Space Activities Committee (ISAC) 14 Arthur C. Clarke: A Prophet Vindicated by Gregory Benford 16 Acting Editor: Douglas Yazell [email protected] Book Review (Subject: Ellington Field in Houston) & Staying Informed 18 Assistant Editors: Scholarship & Annual Technical Symposium (ATS 2008) 19 Jon Berndt Dr. Rattaya Yalamanchili Lunch-and-Learn Summary: Mars Rovers by Dr. Mark Adler/JPL 20 Don Kulba Robert Beremand Dinner Meeting Summary: John Frassanito & Associates 21 Lunch & Learn: Sailing the Space Station with Zero-Propellant Guidance 22 AIAA Houston Section Executive Council Membership 23 Chair: Douglas Yazell Inaugural Space Center Lecture Series: Harrison Schmitt of Apollo 17 24 Chair-Elect: Chad Brinkley Past Chair: Dr. Jayant Ramakrishnan Yuri’s Night Houston by AAS, co-sponsored by AIAA Houston Section 26 Secretary: Sarah Shull Constellation Earth, Michel Bonavitacola, AAAF , Toulouse, France 27 Treasurer: Tim Propp Calendar 30 JJ Johnson Sean Carter Cranium Cruncher and a Pre-College Event: Engineer for a Day 31 Vice-Chair, Vice-Chair, Operations Branch Technical Branch Odds and Ends: EAA Houston Chapter 12, James C.
    [Show full text]
  • Mars Exploration Entry, Descent and Landing Challenges1,2
    Mars Exploration Entry, Descent and Landing Challenges1,2 Robert D. Braun Robert M. Manning Georgia Institute of Technology Jet Propulsion Laboratory Atlanta, GA 30332-0150 California Institute of Technology (404) 385-6171 Pasadena, CA 91109 [email protected] (818) 393-7815 [email protected] Abstract—The United States has successfully landed five interesting locations within close proximity (10’s of m) of robotic systems on the surface of Mars. These systems all pre-positioned robotic assets. These plans require a had landed mass below 0.6 metric tons (t), had landed simultaneous two order of magnitude increase in landed footprints on the order of hundreds of km and landed at sites mass capability, four order of magnitude increase in landed below -1 km MOLA elevation due the need to perform accuracy, and an entry, descent and landing operations entry, descent and landing operations in an environment sequence that may need to be completed in a lower density with sufficient atmospheric density. Current plans for (higher surface elevation) environment. This is a tall order human exploration of Mars call for the landing of 40-80 t that will require the space qualification of new EDL surface elements at scientifically interesting locations within approaches and technologies. close proximity (10’s of m) of pre-positioned robotic assets. This paper summarizes past successful entry, descent and Today, robotic exploration systems engineers are struggling landing systems and approaches being developed by the with the challenges of increasing landed mass capability to 1 robotic Mars exploration program to increased landed t while improving landed accuracy to 10’s of km and performance (mass, accuracy and surface elevation).
    [Show full text]
  • Applied Mathematics & Information Sciences
    Empirical Study on Effects of Compression Algorithms in Web Environment Lukáš Čegan1 1University of Pardubice, Faculty of Electrical Engineering and Informatics, Department of Information Technology, Pardubice, Czech Republic Web resource compression is one of the most useful tools, which is utilized to accelerate website performance. Compressed resources take less time to transfer from server to client. This leads to faster rendering of web page content resulting in a positive impact on the user experience. However, content compression is time consuming and also brings extra demands on system resources. For these reasons, it is necessary to know how to choose a suitable algorithm in relation to particular web content. In this paper we present an empirical study on effects of the compression algorithms which are used in web environment. This study covers Gzip, Zopfi and Brotli compression algorithms and provides their performance comparison. Keywords: Compression, Website, Gzip, Zopfi, Brotli. 1. INTRODUCTION big compression ratio, but they are slow. However, it may not be a hindrance for static content, because it can be Today’s web users are not very patient. They expected easily preprocessed and deployed to the web server. But delivery content from web servers to their devices in a flash. this practice is definitely inapplicable for dynamic Therefore, web developers, UX designers, software generated content because it is created on-the-fly, on the architects, network experts and many others care about server side. For this reasons it is necessary to have a deep many optimization technics and appropriate solutions that knowledge of the performance data of different algorithms help them to delivery whole web content to the client as in different kinds of deployment.
    [Show full text]
  • Technology, Innovation & Engineering Committee Report
    National Aeronautics and Space Administration Technology, Innovation & Engineering Committee Report NASA Advisory Council Presented by: Dr. Bill Ballhaus, Chair July 31, 2015 www.nasa.gov/spacetech TI&E Committee Meeting Attendees July 27-28, 2015 • Dr. William Ballhaus, Chair • Mr. Gordon Eichhorst, Aperios Partners • Mr. Michael Johns, Southern Research Institute • Mr. David Neyland, Consultant • Mr. Jim Oschmann, Ball Aerospace & Technologies Corp. • Dr. Mary Ellen Weber, STELLAR Strategies, LLC Absent: Dr. Matt Mountain, Association of Universities for Research in Astronomy 2 TI&E Committee Meeting Presentations July 27-28, 2015 • Joint Session with HEOMD (STMD Overview, HEO Tech Development Efforts, Hydrocarbon Engine Overview, NASA Launch Services Overview) • Welcome Remarks – Dr. Charles Elachi, Director, JPL • Space Technology Mission Directorate Status and Update – Mr. Stephen Jurczyk, Associate Administrator, STMD – Dr. James Reuther, Deputy Associate Administrator for Programs, STMD • Update on Deep Space Optical Communications Project – Mr. Thomas Glavich, Project Manager, JPL • Update on Deep Space Atomic Clock Project – Dr. Todd Ely, Principal Investigator, JPL – Mr. Allen Farrington, Project Manager, JPL • Update on Low Density Supersonic Decelerator Project – Dr. Mark Adler, Project Manager, JPL – Dr. Ian Clark, Principal Investigator, JPL • Chief Technologist Update – Dr. David Miller, NASA Chief Technologist • Working Lunch with JPL NASA Space Technology Research Fellows 3 National Aeronautics and Space Administration
    [Show full text]
  • Robotic Mars Exploration Strategy 2007–2016
    National Aeronautics and Space Administration Mars Advanced Planning Group 2006 Robotic Mars Exploration Strategy 2007–2016 Daniel J. McCleese Chair and Editor March 2006 Contents 1. Introduction 2 2. Context for 2006 Plan 5 3. Status of Mars Exploration 6 4. Science Pathway and Implementation Strategy 15 5. Sustaining Elements of the Strategy 28 6. Summary 32 In the summer of 2005, the Mars Advanced Planning Group (MAPG) was charged by NASA with updat- ing the 2002 Mars science exploration plan (Mars Exploration Strategy, McCleese et al., 2004) in light of recent scientific findings about Mars, and in re- sponse to new constraints on NASA’s Mars explora- tion program. In accomplishing this request, MAPG found it necessary to broaden the scope of the re- search performed in the exploration program, revise the investigations in the latter half of the coming decade, and adjust the program’s architecture by scheduling key missions beyond the horizon of the plan. The objectives of the 2004 plan were retained in creating the revised plan. MAPG began its work by identifying recent discover- ies and findings from data returned from past and still-active missions: Mars Global Surveyor (MGS); Mars 1. Introduction Odyssey (ODY); Mars Exploration Rovers (MER); and Mars Express (MEx). The group also explored how the stated intent and potential findings from new mission Mars Reconnaissance Orbiter (MRO) might influence the architecture presented in the 2004 plan. A similar evalu- ation was performed on the coming-decade missions, Phoenix and Mars Science Laboratory (MSL), which are now well defined but not yet launched.
    [Show full text]
  • Lesson 6: People of the Cassini Team
    THE CASSINI–HUYGENS MISSION LESSON People of the Cassini Team 6 1.5–2 hrs Students use a diverse collection of profiles of people who work on the Cassini–Huygens mis- sion to learn about science as a human endeavor and to reflect on their own career goals and per- sonal impressions of the mission. MEETS NATIONAL PREREQUISITE SKILLS SCIENCE EDUCATION Reading in the content area of science STANDARDS: Working in small groups History and Nature of Science Interpreting narrative information • Science as a Taking careful notes human endeavor Science in Personal Writing essays and Social Perspectives • Science and technology in BACKGROUND INFORMATION society Background for Lesson Discussion, page 144 A model of the Cassini–Huygens spacecraft at JPL and a few of Questions, page 147 the thousands of Cassini team members. Answers in Appendix 1, page 225 56–63: The Cassini–Huygens Mission 77–80: The People of the Cassini Team EQUIPMENT, MATERIALS, AND TOOLS For the teacher Materials to reproduce Photocopier (for transparencies & copies) Figures 1–19 are provided at the end of Overhead projector this lesson. Chart paper (18" × 22") FIGURE TRANSPARENCY COPIES Color markers; clear adhesive tape 1 1 1 per group 3-ring binder (notebook) 2 1 1 per group 3-hole punch 3–18 1 of each (3-hole punched) For each group of 3 to 4 students 19 1 per student Pencils (3-hole punched) Red and blue markers (optional) Chart paper (optional) Atlas or world map (optional) 143 Saturn Educator Guide • Cassini Program website — http://www.jpl.nasa.gov/cassini/educatorguide • EG-1999-12-008-JPL Background for Lesson Discussion LESSON 6 In Part II (Making Connections to Cassini), • What do you notice about the work that is Step 6, discussion questions might include: required for a space mission? It is important to recognize the vast number and • What was missing from the Jobs Chart that was diversity of talents, interests, and careers neces- created at the beginning of the lesson compared sary to support and carry out a space mission.
    [Show full text]
  • LCH-Png-Chapter.Pdf
    1 Overview PNG, the Portable Network Graphics format, is a robust, extensible, general-purpose and patent-free image format. In this chapter we briefly describe the events that led to its creation in early 1995 and how the resulting design decisions affect its compression. Then we examine PNG’s compression engine, the deflate algorithm, quickly touch on the zlib stream format, and discuss some of the tunable settings of its most popular implementation. Since PNG’s compression filters are not only critical to its efficiency but also one of its more unusual features, we spend some time describing how they work, including several examples. Then, because PNG is a practical kind of a format, we give some practical rules of thumb on how to optimize its compression, followed by some “real-world” comparisons with GIF, TIFF and gzip. Finally we cover some of the compression-related aspects of MNG, PNG’s animated cousin, and wrap up with pointers to other sources for further reading. 2 Historical Background Image formats are all about design decisions, and such decisions often can be understood only in an historical context. This is particularly true of PNG, which was created during—and as part of—the “Wild West” days of the Web. Though PNG’s genesis was at the beginning of 1995, its roots go back much further, to the seminal compression papers by Abraham Lempel and Jacob Ziv in 1977 and 1978.[?, ?] The algorithms described in those papers, commonly referred to as “LZ77” and “LZ78” for obvious reasons,[?] spawned a whole host of refinements.
    [Show full text]
  • Data Compression Algorithms in Fpgas
    Data Compression Algorithms in FPGAs Gonçalo César Mendes Ribeiro Thesis to obtain the Master of Science Degree in Electrical and Computer Engineering Supervisor: Prof. Horácio Cláudio de Campos Neto Examination Committee Chairperson: Prof. António Manuel Raminhos Cordeiro Grilo Supervisor: Prof. Horácio Cláudio de Campos Neto Members of the Committe: Prof. Pedro Filipe Zeferino Tomás May 2017 Acknowledgements I would like to thank Professor Horácio Neto, who accepted to be a part of this journey as my supervisor and always helped me when I needed. I also thank the Electronic System Design and Automation (ESDA) group of INESC-ID — which I integrated during the course of this work — for the resources they provided me. A thank you to Charles Bloom and Mark Adler, who did not leave me without a reply when I contacted them with some questions. Also, I would like to thank the friends who accompanied me during my time at IST. Alongside some of them I helped build HackerSchool, which helped me grow and made these years more enjoyable. I would also like to express my gratitude to my parents and family without whom I could not have started pursuing this course, much less finish it with this work. And finally, to Rita, who is always supportive, a great company and makes me smile. i Abstract Data compression is increasingly important as more and more data is produced, transferred and stored on a daily basis. It allows to reduce storage costs, speed up data transfers over limited bandwidth, reduce network congestion and even improve energy efficiency in wireless devices.
    [Show full text]
  • Network Working Group P. Deutsch Request for Comments: 1950 Aladdin Enterprises Category: Informational J-L
    Network Working Group P. Deutsch Request for Comments: 1950 Aladdin Enterprises Category: Informational J-L. Gailly Info-ZIP May 1996 ZLIB Compressed Data Format Specification version 3.3 Status of This Memo This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind. Distribution of this memo is unlimited. IESG Note: The IESG takes no position on the validity of any Intellectual Property Rights statements contained in this document. Notices Copyright (c) 1996 L. Peter Deutsch and Jean-Loup Gailly Permission is granted to copy and distribute this document for any purpose and without charge, including translations into other languages and incorporation into compilations, provided that the copyright notice and this notice are preserved, and that any substantive changes or deletions from the original are clearly marked. A pointer to the latest version of this and related documentation in HTML format can be found at the URL <ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html>. Abstract This specification defines a lossless compressed data format. The data can be produced or consumed, even for an arbitrarily long sequentially presented input data stream, using only an a priori bounded amount of intermediate storage. The format presently uses the DEFLATE compression method but can be easily extended to use other compression methods. It can be implemented readily in a manner not covered by patents. This specification also defines the ADLER-32 checksum (an extension and improvement of the Fletcher checksum), used for detection of data corruption, and provides an algorithm for computing it.
    [Show full text]
  • NASA Entry, Descent, and Landing Technology Area Roadmap
    National Aeronautics and Space Administration DRAFT Entry, DEscEnT, AnD LAnDing RoadmAp Technology Area 09 Mark Adler, Chair Michael Wright, Chair Charles Campbell Ian Clark Walt Engelund Tommaso Rivellini November • 2010 DRAFT This page is intentionally left blank DRAFT Table of Contents Foreword Executive summary TA09-1 1. Detailed Portfolio Discussion TA09-6 1.1. Aerobraking, Aerocapture, and Entry Systems (AAES) TA09-6 1.1.1. Rigid Thermal Protection Systems (TPS) (cross cutting with TA05-Thermal Management) TA09-8 1.1.2. Flexible Thermal Protection Systems (cross cutting with TA05-Thermal Management) TA09-9 1.1.3. Rigid Aeroshells TA09-10 1.1.4. Deployable Aeroshells TA09-11 1.1.5. Entry Instrumentation and Health Monitoring TA09-11 1.1.6. Entry Modeling and Simulation TA09-12 1.2. Descent TA09-13 1.2.1. Attached Deployable Decelerators TA09-13 1.2.2. Trailing Deployable Decelerators TA09-14 1.2.3. Supersonic Retropropulsion (SRP) TA09-14 1.2.4. Guidance, Navigation, & Control Sensors TA09-15 1.2.5. Descent Device Modeling & Simulation TA09-15 1.3. Landing TA09-16 1.3.1. Touchdown Systems TA09-16 1.3.2. Egress and Deployment TA09-17 1.3.3. Landing Propulsion TA09-17 1.3.4. Landing Guidance, Navigation, and Control for Large Bodies TA09-17 1.3.5. Small Body Systems TA09-18 1.4. Vehicle Systems Technology TA09-18 1.4.1. Separation Systems TA09-19 1.4.2. Vehicle Technology TA09-20 1.4.3. Atmospheric Modeling and Surface Characterization TA09-22 2. Infrastructure TA09-23 3. Immediate Actions TA09-24 Acronyms TA09-25 Acknowledgements TA09-25 References TA09-26 DRAFT Foreword NASA’s integrated technology roadmap, including both technology pull and technology push strategies, considers a wide range of pathways to advance the nation’s current capabilities.
    [Show full text]