Department of Aeronautics and Astronautics

Personnel Information

After seven outstanding years of service, Professor Edward Crawley stepped down as department head. His replacement is Professor Wesley L. Harris.

Professor Edward M. Greitzer has finished the manuscript of a text entitled Internal Flow: Concepts and Applications. The book is scheduled for publication in early 2004. The coauthors are C. S. Tan (principal research engineer) and M. B. Graf. The prospective audience spans from first-year graduate students to practicing engineers. While a number of excellent texts focus on the external flow around aircraft, ships, and automobiles, for many engineering fluid devices (jet engines or other propulsion systems and fluid machinery) the motion is appropriately characterized as an internal flow, and there is no unified treatment of these situations. The aim of the text is to provide such a treatment.

Professor Moe Win and his graduate students are working on the application of mathematical and statistical theories to communication, detection, and estimation problems, with application to measurement and modeling of time-varying channels, design and analysis of multiple antenna systems, ultrawide bandwidth (UWB) communications systems, optical communications systems, and space communications systems. Specific accomplishments of Professor Win include:

Professor Win has been involved actively in organizing and chairing sessions and has served as a member of the Technical Program Committee in a number of international conferences. He currently serves as the Technical Program chair for the Instituteof Electricaland Electronics Engineers (IEEE) Communication Theory Symposium of ICC-2004. He is the secretary for the Radio Communications Technical Committee and the current editor of Equalization and Diversity for the IEEE Transactions on Communications. Recently, he served as an executive committee member for the International Workshop on Ultra Wideband Systems (2003); Technical Program chair for the IEEE Conference on Ultra Wideband Systems and Technologies (2002); Technical Program vice chair for the IEEE International Conference on Communications (2002); and a guest-editor for the 2002 IEEE Journal on Selected Areas in Communications, Special Issue on "Ultra-Wideband Radio in Multiaccess Wireless Communications."

Professor Moe Win has been invited to deliver a plenary presentation at the IEEE 8th International Symposium on Spread Spectrum Techniques and Applications, Sydney, Australia, August 2004. He delivered invited plenary presentations at the International Workshop on Ultra Wideband Systems, Oulu, Finland, June 2003; the International Conference on Present and Future of UWB Technology, Seoul, Korea, December 2002; the 3rd International Symposium on Mobile Multimedia Systems and Applications, Delft, Netherlands, December 2002; and the European Conference on Wireless Technology, Milano, Italy, September 2002. He was a distinguished lecturer at the Annual Assembly of the CNIT (Consorzio Nazionale Interuniversitario per le Telecomunicazioni) and GTTI (Gruppo di Telecomunicazioni e Teoria dell' Informazione), Trieste, Italy, June 2002. He also gave invited talks at the Information Technology Conference, "Extreme Communications: A Radical Rethinking of Business, Technology, and Regulatory Strategies," MIT, Cambridge, MA, April 2003; the 32nd Annual IEEE Communication Theory Workshop, Mesa, AZ, April 2003; the Korea Electronics Technology Institute, Ministry of Commerce, Industry, and Energy, Seoul, Korea, December 2002; the Radio Communications Laboratory, Nokia Research Center, Helsinki, Finland, December 2002; and the Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA, September 2002.

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Undergraduate Program

Enrollment over the Last Ten Years

  92–93 93–94 94–95 95–96 96–97 97–98 98–99 99–00 00–01 01–02 02–03
Sophomores 33 36 36 30 46 40 48 59 68 56 64
Juniors 60 31 37 31 23 33 37 40 53 69 51
Seniors 66 66 38 37 29 24 35 37 45 53 70
Totals 159 133 111 98 98 97 120 136 166 178 185
Women % 28% 32% 31% 29% 26% 30% 33% 30% 32% 33% 35%
Minorities % 12% 23% 19% 16% 18% 22% 15% 12% 21% 22% 30%

Note: 2002–2003 data are based on fifth-week enrollment.

Graduate Program

Enrollment Statistics, Academic Year 2002–2003

February 2003 June 2003 September 2003 Total
Applications 38 11 280 329
Admitted 11 9 122 142
Accepted Admission 5 9 74 88
# SM 5 9 70 84
# Phd 0 0 4 4
# Minority 0 1 8 9
# SM 0 1 8 9
# Phd 0 0 0 0
# Female 2 2 15 19
# SM 2 2 14 18
# Phd 0 0 1 1
Funding Accepted
# Fellowship (MIT) 0 2 22 24
# Fellowship (other) 0 2 1 3
# RA & Draper 4 2 26 32
# TA 0 0 2 2
# Other 0 0 0 0

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Faculty Awards

Professor Vincent W. S. Chan was named professor of telecommunications by the Massachusetts Telecommunications Council.

Professor John-Paul Barrington Clarke received the American Institute of Aeronautics and Astronautics (AIAA) Distinguished Lecturer Award.

Professor Olivier L. de Weck received the (MIT internal) Robert N. Noyce career development professorship (2002–2005) and won 2nd place in the (external) International Council on Systems Engineering Robotics Competition, 2003 (faculty team advisor).

Professor Jonathan P. How received the Institute of Navigation Burka Award in recognition of outstanding achievement in the preparation of papers contributing to the advancement of navigation and space guidance.

Professor Manuel Martinez-Sanchez received (together with Zolti Spakovszky, Fred Ehrich, and three others) the American Society of Mechanical Engineers(ASME) Melville Award for Best Paper of the Year in Mechanical Engineering.

Professor Eytan H. Modiano and Li-Wei Chen received Honorable Mention in the Best Paper Award competition at the Infocom 2003 Conference for their paper, "Efficient Routing and Wavelength Assignment for Reconfigurable WDM Networks with Wavelength Converters."

Professor Earll M. Murman received the Vickie Kerrebrock Award.

Professor Zoltan S. Spakovszky received the ASME Melville Medal, 2003; the NASA Honor Award; the Enhanced Aeroengine Compressor Stability Team Group Achievement Award, 2003; the AIAA Undergraduate Advising Award, 2003 (Institute Award); and the ASME International Gas Turbine Institute's Turbomachinery Committee Best Paper Award, 2002.

Professor Mark S. Spearing became an associate fellow of the AIAA.

Professor Ian A. Waitz received the NASA 2003 Turning Goals ino Reality Award for work on aviation noise reduction. He also became a MacVicar Faculty Fellow.

Professor Moe Win received the International Telecommunications Innovation Award from Korea Electronics Technology Institute; the MIT School of Engineering Educational Innovation Award; the Young Investigator Award from the Office of Naval Research; and the IEEE Antennas and Propagation Society's Sergi A. Schelkunoff Transactions Prize Paper Award.

Professor Laurence A. Young was the subject of a "Festschrift" in his honor, a celebration and symposium recognizing his career in space research: the 6th Symposium on the Vestibular Organs and the Exploration of Space, held in Portland OR, October 2002. The proceedings will be published as a NASA Special Publication, with selected papers appearing in a special issue of the Journal of Vestibular Research.

Professor Wesley L. Harris received the Arthur C. Smith Award.

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Staff Awards

Bill Litant was named one of the first three lifetime members of the National Association of Bar Executives (an affiliate of the American Bar Association), Section on Communications.

Margaret (Peggy) Udden received the Infinite Mile Award for Excellence from the School of Engineering.

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Undergraduate Awards

The Andrew Morsa Memorial Award—for demonstration of ingenuity and initiative in the application of computers to the field of aeronautics and astronautics—was awarded to seniors Elizabeth Bly and Brian Guzman for "demonstration of ingenuity and initiative in the development of a color recognition system in a single chip, for use in remote sensing operations." The Morsa Award was also received by senior Jennifer Underwood for "demonstrating outstanding ingenuity and initiative in the application of computers to the EMFFORCE Satellite System Test Bed in Subject 16.686."

The Yngve Raustein Award—given to a unified engineering student who best exemplifies the spirit of Yngve Raustein and to recognize significant achievement in unified engineering—was awarded to sophomore Christopher Sequeira for "outstanding team work, intellectual curiosity, positive attitude, and overcoming obstacles in pursuit of aerospace engineering exemplifying the spirit of Yngve Raustein."

The David J. Shapiro Memorial Award—given to Aeronautics and Astronautics (Aero/Astro) undergraduate students to pursue special aeronautical projects that are student initiated, and/or to support foreign travel for the enhancement of scientific/technical studies and research opportunities—was given to sophomore Thomas Coffee for his project, "Mars Gravity Biosatellite Centrifuge Study on Vestibular Effects of Artificial Gravity Centrifugation on Mice." The Shapiro Award was also received by junior Douglas Quattrochi for "travel to conduct interviews on space tourism."

The Apollo Program Prize—given to an Aero/Astro student who conducts the best undergraduate research project on the topic of humans in space—was given to senior Paul Wooster for "leadership of the Mars gravity project to test the feasibility of artificial gravity with mice."

The Leaders for Manufacturing Prize—given to 16.622 teams who have used their project to directly deal with issues related to the interaction between manufacturing and engineering—was given to senior Jesús Bolivar for "designing, building, and testing a liquid nitrogen system for maintaining high temperature superconducting electro-magnet coils at cryogenic temperatures."

The United Technologies Corporation Award—given for outstanding achievement in the design, construction, execution, and reporting of an undergraduate experimental project—was awarded to seniors Timothy Pigeon and Ryan Whitaker for "outstanding achievement in the design, demonstration, and reporting of a near vacuum hall thruster." The United Technologies Award was also presented to seniors Philip Springmann and Glenn Tournier for "outstanding achievement in the design, demonstration, and reporting of missile control through center of pressure motion"; and to Stefano Alziati and Warren Bennett (exchange students from Cambridge University) for "outstanding achievement in addressing difficulties associated with the development of test procedures for ice climbing equipment."

The James Means Memorial Award—given for excellence in space systems engineering—was presented to senior Elizabeth Bly for "carrying out numerous technical tasks for the EXOSPHERES Project with skill, leadership, and enthusiasm."

The James Means Memorial Award—given for excellence in flight vehicle engineering—was presented to the four teams in this year's 16.82 class for "excellence in the design of an unmanned cargo aircraft system." The four teams were:

The Admiral Luis De Florez Award—given for original thinking or ingenuity—was awarded to seniors Richard Sheridan and Margaret Stringfellow for "original thinking and ingenuity in the design and execution of a Mars Terrain Generator for defining the performance of RRT–based path-planning algorithms."

The Henry Webb Salisbury Award—given for outstanding academic achievement—was presented to senior Krzysztof Fidkowski for "superior academic achievement in every category of the undergraduate degree program of the Department of Aeronautics and Astronautics, and for demonstrated excellence in theory, design, and implementation covering several components of aeronautics and astronautics."

The Aeronautics and Astronautics Teaching Assistantship Award—given to a teaching assistant or assistants in one of the department's undergraduate or graduate subjects who has demonstrated conspicuous dedication and skill in helping fulfill the subject's educational objectives—was presented to the 16.62x teaching assistants, Daniel Craig, Gregory Mark, and Caroline Twomey.

The American Institute of Aeronautics and Astronautics Undergraduate Advising Award for 2002–2003 was presented to Professor Zoltan Spakovszky.

The American Institute of Aeronautics and Astronautics Teaching Award for 2002–2003 was presented to Professor Ian Waitz.

The Sigma Gamma Tau Graduate Teaching Award for 2002–2003 was presented to Professor James Kuchar.

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Aerospace Systems Division of Instruction

The Aerospace Systems Division is responsible for instruction and research in systems engineering, a discipline that denotes the methods used in architecting, designing, manufacturing, and operating the highly complex and demanding systems in the field of aeronautics and astronautics. The division is comprised of nine faculty with research and teaching interests in systems engineering, together with a group of affiliates from within the department and the School's Engineering Systems Division whose interests encompass aerospace systems. During AY2003, the division offered four undergraduate and thirteen graduate subjects, including two new ones: 16.85 Aircraft Systems Engineering and 16.86 Air Transportation Systems Architecting. The division developed "roadmaps" for graduate studies in three domains: air transportation systems, aircraft systems, and space systems. These roadmaps provide students with a holistic framework for planning their degree programs. Included are learning objectives, required core subjects, recommended tracks for specialization, and integration of research and industry experiences. A search for a dual faculty position with the Engineering Systems Division was concluded with the hiring of Dr. Annalisa Weigel, who will join the faculty in the spring of 2004. The division was saddened with the untimely passing of Dr. Joyce Warmkessel in February 2003.

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Man-Vehicle Laboratory

The Man-Vehicle Laboratory (MVL) continues to be at the forefront of research in aerospace physiology, human factors, and cognitive engineering, supported by NASA, the National Space Biomedical Research Institute, DOT, FAA, and industry. Professor Young completed a nine-month sabbatical at the College de France in Paris, and Professor Newman returned in June after completing a circumnavigation as part of her Galatea Odyssey World Education Project, which introduces students to history, geography, science, and technology by means of local lectures, visits aboard, and an expedition web site.Professor Newman will be leading the Technology and Policy Program during the coming year.Former NASA astronaut Jeffrey Hoffman joined the MVL as professor of the practice and is codirector along with Professor Young of the Space Grant Consortium.

In the space research domain, the Man-Vehicle Laboratory continues a multiyear effort to build the suite of spaceflight-qualified virtual reality display hardware for the International Space Station (ISS) Human Research Facility, with the assistance of professional engineering staff from MIT's Center for Space Research. The hardware supports VOILA (Visuomotor and Orientation Investigations in Long Duration Astronauts), a family of nine flight experiments developed under MVL director Dr. Charles Oman's leadership by a US–French-Italian-Canadian science team, to be conducted on the ISS in 2004–2005. Professor Dava Newman's new microgravity disturbance experiment for ISS, MICRO-G, is approved and has entered definition stage. Meanwhile, ground laboratory experiments continue in the areas of intermittent, short-radius artificial gravity (Professor Young), visual orientation and spatial memory (Dr. Oman), and mechanical counterpressure space suits (Professors Newman and Hoffman). Dr. Oman leads all National Space Biomedical Research Institute (NSBRI) programs in the neurovestibular discipline (42 investigators from 21 institutions). Professors Young and Hoffman have also worked to define MIT's potential role in a NASA International Space Station Science Institute. Dr. Oman serves on the Space Station Utilization Advisory Subcommittee of the NASA Advisory Council. He co-organized the 6th Symposium on the Role of the Vestibular Organs in Space Exploration, Portland, OR, and edited a special issue of the Journal of Vestibular Researchdevoted to space neurovestibular research progress.

In the cockpit human factors domain, Dr. Oman and Professor James Kuchar completed experiments on time-critical decision making in a military aircraft route replanning context. Results were presented at the 2002 International Conference on Human-Computer Interaction in Aeronautics in Boston. Dr. Oman began a new research program on pilot attention and eye movement patterns using hidden Markov models in collaboration with DOT Volpe Research Center colleagues as part of a research program on airliner heads up display certification standards.

In the educational domain, Dr. Oman collaborated with Professor Kuchar and Dr. Michelle Yeh of the Volpe Research Center to develop a new version of the undergraduate and graduate subjects 16.400 and 16.453 Human Factors Engineering. Professor Newman continued to develop new curricula in the space biomedical engineering area, supported by the NSBRI. Over Independent Activities Period 2003, Dr. Oman and Brian Nield of Boeing held a 4-day, 22-hour Boeing 767 systems and automation course, utilizing the Project iCampus flight simulation lab facilities, Boeing-supplied computer-based training software, and an aircraft made available in the evenings at Logan Airport by Delta Airlines. Several pilot alumni also assisted as instructors. Dr. Oman serves as student chapter of the Human Factors and Ergonomics Society. Professor Young's translation of Ernst Mach's Fundamentals of the Theory of Movement Perception was published by Kluwer.

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Software Engineering Research Laboratory

Research in the Software Engineering Research Laboratory (SERL) focuses on topics related to the design of complex systems having software components. The development of software in these systems cannot be separated from system engineering activities, and much of the research in the lab would more properly fit into the category of systems engineering than software engineering. SERL research is cross-disciplinary and spans aeronautics and astronautics, computer science, human factors and cognitive engineering, system safety engineering, and other disciplines and applications using computers for control (such as transportation and medical devices). SERL researchers are working with Eurocontrol, NASA, Raytheon, Ford, and others on such diverse applications as air traffic management, aircraft avionics and flight management systems, autonomous vehicles, robots, the International Space Station, and interplanetary spacecraft. Research topics include model-based system and software engineering, system safety engineering, system and software requirements specification and analysis, and design of human-computer interaction (cognitive engineering).

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Space Grant Consortium

The Massachusetts Space Grant Consortium (MASGC) includes MIT (lead institution), Tufts University, Wellesley College, Harvard University, Boston University, the University of Massachusetts, the Worcester Polytechnic Institute, the Marine Biological Laboratory, the Five College Astronomy Department, Northeastern University, Williams College, Holy Cross University, the Boston Museum of Science, the Christa McCaulliff Center/Framingham State College, and the Charles Stark Draper Laboratory. MASGC continues to support a wide variety of programs aimed at education/public outreach and aerospace workforce development. The consortium contributes to the education of precollege teachers in space science and engineering through summer workshops run by the Wright Center at Tufts. It continues to support undergraduate research through the MIT Undergraduate Research Opportunities Program (UROP) and similar programs at affiliate institutions. It also provided graduate fellowships last year for three students. MASGC supported several students at the summer Space Academies at NASA's Goddard and Ames Centers. It increased the number of companies involved in placing students for summer employment in the aerospace industry. Last November, in cooperation with the Boston Museum of Science, MASCG hosted the annual Space Day, inviting students supported by the consortium to present the results of their research to an assembly of Boston-area high school students. The students then heard a lecture by Dr. John Grunsfeld, NASA astronaut, on "New Eyes for Space Exploration: Upgrading the Hubble Space Telescope." During the spring semester at MIT, MASGC sponsored a popular undergraduate seminar on Modern Space Science and Engineering, with guest speakers from our industrial and academic affiliates. The annual Space Grant Public Lecture this year was given by Dr. Jim Garvin, lead scientist for Mars Exploration, NASA, on "The Quest for Mars: Scientific and Human Destiny?"

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Technology Laboratory for Advanced Composites

The personnel of the Technology Laboratory for Advanced Composites (TELAC) during AY2003 included three Faculty members (Lagace, Radovitzky, and Spearing), one research scientist, one engineering specialist, four postdoctoral researchers, nineteen graduate students, eleven UROP students, and five undergraduate students in the undergraduate projects class (16.621/2) who performed their research projects in the laboratory. Brian Wardle, a graduate of the laboratory, arrived in June 2002 as an assistant professor after four years in business. Professor Carlos Cesnik was a visitor in the lab from the University of Michigan during 2002–2003. Four students finished their master's theses and four doctorates were completed during the past year. Professor Spearing was made an associate fellow of the AIAA in October 2002. Approximately 52 research papers and reports were published during the year by laboratory personnel. The paper by S. S. Kessler, S. M. Spearing, and C. Soutis entitled "Structural Health Monitoring in Composite Materials Using Lamb Wave Methods" was awarded the Best Paper Prize for functional composites at the 17th Meeting of the American Society for Composites, Purdue University, October 2002.

Laboratory personnel have been strongly involved in the Singapore-MIT Alliance and the Cambridge-MIT Institute, both in the area of micro-electro-mechanical systems (MEMS). Continuing sponsored research projects include the following: numerical modeling of blast-structure interaction; the accelerated insertion of materials (composites); actively conformable aerodynamic control surfaces; direct simulation of polycrystals; highly flexible active composite wings; conformable aerodynamic surfaces; fatigue of GLARE and Ti/Gr hybrid laminates; materials, structures, and package design for high-power density microsystems; metal-composite adhesive joining; piezo-induced fatigue of adhesive joints; and structural health monitoring for composites.

The laboratory continues to have extensive collaborations with industry, including Boeing, the Draper Laboratory, and Rockwell Scientific. Seth Kessler and Mark Spearing were coinventors on the patent for the Wide Area Surveillance Projectile Flyer Assembly, which was recognized for being the best patent from the Draper Laboratory during 2002. Collaborations exist with other academic institutions, including the California Institute of Technology, Cambridge University, Clark Atlanta University, the University of Michigan, and Stanford University. Within MIT, strong collaborations exist with the Gas Turbine Laboratory, the Fluid Dynamics Research Laboratory, the Microsystems Technology Laboratory, and groups in Chemical Engineering, Materials Science and Engineering, and Mechanical Engineering.

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Lean Aerospace Initiative

Current Goals, Objectives, and Priorities

In its third phase of operations—the "Enterprise Value Phase" (September 1, 2002–August 31, 2005)—the Lean Aerospace Initiative (LAI) shifted its research focus to understanding the interactions between and across various core enterprise functions. The main organizing principles of this new phase reflect the crucial insight set forth in the 2002 published book, Lean Enterprise Value: Insights From MIT's Lean Aerospace Initiative. This is that "lean" is not just a matter of elimination of waste; rather, becoming lean is a process of eliminating waste with the goal of creating value for enterprise stakeholders.

With the knowledge and tools researched and developed in this phase, the national aerospace enterprise will be able to more quickly improve its capability and agility in delivering best life-cycle value. Additionally, enterprise-level research will provide the foundation for emerging systems-thinking approaches to enterprise architecting and enterprise transformation.

During the past year, LAI continued to uphold its mission to research, develop, and promulgate knowledge, principles, and practices—tools to enable and accelerate the envisioned transformation of the greater US aerospace enterprise through people and processes. The following six goals provide the framework for consortium efforts:

Transforming the US Aerospace Enterprise

Industry members of the consortium have, with the support of the LAI, made significant progress in implementing lean principles and practices in production operations. As a consortium, there are noted "islands of success," but the expectation is to continue recognizing opportunities for the enterprise, as it is the latter that represents greater value. Consider these enterprise level value propositions:

To catalyze future enterprise transformation, particularly among government stakeholders, LAI rolled out Lean Now in 2002. Lean Now, a government-conceived initiative, is a total enterprise team facilitated through the LAI venue to leverage collective knowledge, eliminate barriers that impede progress, and capitalize on government and industry teamwork. Lean Now taps industry expertise by creating a cadre of coaches and trainers known as LAI Subject Matter Experts. The effort takes a spiral approach as it engages program prototypes. Spiral One included the F/A-22, F-16, and Global Hawk system program offices.

Accomplishments, Research Results, and Knowledge Deployment

In the past year, LAI also stepped up efforts to help transform the US aerospace enterprise by developing and deploying education programs as well as leadership and transformational tools steeped in ongoing research .

LAI Research

Key questions drive ongoing and future LAI research efforts. These are:

Recently published research in the form of reports, conference papers, and student theses includes observations and recommendations such as these: "The Pursuit of Acquisition Entrepreneurs"; "A Holistic Approach to Manufacturing System Design in the Defense Aerospace Industry"; "Value Stream Analysis and Mapping for Product Development"; "Lean Enterprise Self-Assessment as a Leading Indicator for Accelerating Transformation in the Aerospace Industry"; "Multi-Attribute Tradespace Exploration with Concurrent Design as a Value-Centric Framework for Space System Architecture and Design"; "Product Development Processes and Their Importance to Organizational Capabilities"; and "Multi-Attribute Tradespace Exploration and its Application to Evolutionary Acquisition."

LAI Products

LAI Knowledge Deployment

"Transformation across Enterprise Boundaries—Pioneering the Future of Aerospace." This annual stakeholder event brought more than 250 lean learners together from across the aerospace industry to help shape the future of the aerospace industry by examining past and present accomplishments and the risk takers behind them. LAI's codirector, Professor Debbie Nightingale opened the forum by conjuring up imagery of the Wright Brothers in the early days of flight, when people thought there was something "strange about man with wings." She challenged audience members by asking, "Are you ready to flap your wings?" A few odd stares might be the price of innovation. Other keynote leadership perspectives were provided by General Lester Lyles, commander, Air Force Materiel Command, and Dan Burnham, chairman and CEO, Raytheon Company, who shared their perspectives on what it takes to transform government and industry perspectives. "We want to enable an expeditionary mindset and culture, be innovative, adaptive, and responsive, known as easy to do business with as well as effective and efficient, " said General Lyles. "LAI is poised to enable air force acquisition to meet today's challenges."

Moving Forward

LAI has grown and flourished as an innovative model of industry, government, labor, and university partnership. The consortium also represents a true learning community with the ability to leverage multiple perspectives for longer-term solutions. Through this community, LAI is able to open and sustain knowledge sharing, create a common vocabulary, infuse new ideas into the industry, and enhance communication among all stakeholders. This accelerates lean transformation efforts by bridging sectors and cultures as well as organizational functions, layers, and competing interests. It also creates a system to rapidly diffuse best practices throughout the enterprise. So LAI is, in fact, poised to do for the rest of the enterprise what it did for manufacturing.

Today, LAI's learning community includes stakeholders from 38 organizations from aerospace companies, US government offices and programs, organized labor, and MIT. This consortium-guided research program continues to be led by the MIT Department of Aeronautics and Astronautics in close collaboration with MIT's Sloan School of Management and managed under the auspices of the Center for Technology, Policy, and Industrial Development. LAI also collaborates internationally with the Lean Aerospace Research Program at Linköping University and the UK LAI.

LAI Leadership

Over the past year LAI has been managed by a trio of codirectors representing the various stakeholder interests. They are Professor Deborah Nightingale, Department of Aeronautics and Astronautics, Professor Tom Allen, MIT Sloan School of Management, and Frederick "Terry" Bryan of Raytheon. This management model will continue in the future with John Carroll, professor of behavioral and policy sciences in the Sloan School of Management, succeeding Tom Allen on July 1, 2003.

The Lean Academy is about collaborative education in applying lean principles for the next generation of workforce. Pictured here – Professor Earll Murman, MIT Department of Aeronautics and Astronautics, leads Rolls Royce interns through LAI's lean enterprise "game."

General Lester Lyles, Commander Air Force Materiel Command, speaks to the challenges of Air Force acquisition today during the annual LAI Conference March 2003.

More information about the Lean Aerospace Initiative can be found on the web at http://web.mit.edu/lean/.

Lean Sustainment Initiative

The mission of the Lean Sustainment Initiative (LSI), established in 1997, is to enable a fundamental transformation of the US commercial and military maintenance, repair, and overhaul (MRO) industries into cost-effective, quality-driven, timely, and responsive support enterprises. As a joint academic-military-industry consortium, LSI develops research-based recommendations for systemic change followed by the implementation of military-industry pilot projects to demonstrate the impact of the recommendations on the MRO effectiveness of the enterprises.

Aeronautics and Astronautics Department professor Wesley L. Harris is LSI director. He was named head of Aero/Astro as of July 1, 2003. This year he was selected cochair of the American Institute of Aeronautics and Astronautics Product Support and Logistics Technical Committee.

More information about LSI can be found on the web at http://www.leansustainment.org/.

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Space Systems Laboratory

The Space Systems Laboratory (SSL), affiliated with the Department of Aeronautics and Astronautics at the MIT, was founded in 1995. The SSL has the mission of developing the technology and systems analysis associated with small spacecraft, precision optical systems, and International Space Station technology research and development. The laboratory encompasses expertise in structural dynamics, control, thermal technology, autonomy, space power, propulsion, MEMS, and software development and systems. A major activity in this laboratory is the development of small spacecraft thruster systems as well as looking at issues associated with the distribution of function among satellites (distributed satellite systems). In addition, technology is being developed for spaceflight validation in support of a new class of space-based telescope that exploits the physics of interferometry to achieve dramatic breakthroughs in angular resolution. The objective of the laboratory is to explore innovative concepts for the integration of future space systems and to train a generation of researchers and engineers conversant in this field.

Distributed Satellite Systems

The objective of the SSL's research into distributed satellite systems is to understand when and why it makes sense to distribute mission functionality across multiple satellites. To this end, the SSL has developed the Generalized Information Network Analysis (GINA) systems architecting methodology for conducting quantitative design trades at the mission concept level. In addition, several enabling technologies are being developed to support such mission concepts.

Generalized Information Network Analysis

The fundamental assumption that MIT's GINA methodology makes is that almost all envisioned satellite systems are information disseminators that can be represented as information transfer networks. Whether the network allows one to obtain a navigational fix, communicate with a colleague, send data files around the globe, or provide an image of a stellar nursery to a scientist, all of these networks fundamentally transfer information between well-defined origin-destination pairs. Furthermore, satellite networks must be seen as a part of the wider information network in which they are imbedded or else unbiased comparative analyses cannot be made (e.g., terrestrial fiber optic vs. satellite links).

GINA is currently an extensive modeling framework that is used to quantify a mission's life-cycle productivity and cost, the ratio of which corresponds to the efficiency of the mission. This framework is currently being used extensively to architect the air force's TechSat21 mission as well as NASA's Terrestrial Planet Finder mission.

Electromagnetic Formation Flight (EMFF)

The SSL has developed Electromagnetic Formation Flight (EMFF), an innovative method for maneuvering satellites in close proximity relative to each other without the need for propellant. Elimination of the need for a consumable, such as propellant, significantly extends the lifetime of satellite formation flight missions. Electromagnets, composed of high-temperature superconductors, are used to control altitude, relative spacing, and rotate the array on the sky. EMFF is receiving serious consideration from space telescope missions such as NASA's Terrestrial Planet Finder mission.

Formation Flight and Sparse Aperture Synthesis

The use of distributed satellites enables large space telescopes to be developed, applying principles of sparse apertures that are a fraction of the cost of monolithic systems. Technical challenges that arise, however, originate from the need to form favorable subaperature geometry through spacecraft formation flight while in the presence of environmental constraints such as orbital dynamics, collision avoidance,and so on. The SSL has developed methods for trading aperture performance against propellant use by finding innovative ways in which to use orbital dynamics, formation flight, and tethers to maintain and reconfigure the spacecraft geometry.

Space Telescope Dynamics and Controls

The SSL has developed the Dynamics, Optics, Controls, and Structures (DOCS) software toolset for analyzing and optimizing the coupled behavior of these disciplines for precision systems such as space telescopes. DOCS provides an immersive environment where complex trades between system design, dynamic behavior, optical layout, and control formulation can be easily conducted on these complex systems. DOCS is currently being used to analyze and design NASA's Space Interferometry Mission, Next Generation Space Telescope, and Terrestrial Planet Finder Mission.

Microgravity Laboratories on the International Space Station

Over the past decade, the SSL has flown five dynamics and controls laboratories on the space shuttle and MIR. The SSL is the leader in the design of dynamics and controls laboratories for the conduct of fundamental research in microgravity conditions.

SPHERES

The SPHERES satellite formation flight test bed was built collaboratively between the SSL and the MIT Department of Aeronautics and Astronautics as a part of an undergraduate educational experiment in Conceive, Design, Implement, Operate. Over the course of a three-semester undergraduate subject, 13 students started with a blank sheet of paper, designed and built a world-class formation flight test bed, and ended by operating their test bed on NASA's KC-135 microgravity aircraft. SPHERES is now transitioning to an International Space Station laboratory, where it will support up to a year of fundamental formation flight research. SPHERES is manifest on the shuttle (STS-116), which has a "no earlier than" launch date of May 2004.

Orion Formation Flying Experiment

A key focus of our research is navigation and control issues for a revolutionary new approach to space science that uses distributed arrays of simple but highly coordinated spacecraft. This approach, called formation flying, requires that we accurately maintain a spacecraft's position relative to the other vehicles in the fleet to ensure that they avoid collisions and collect the best possible science data. NASA and the Department of Defense are particularly interested in formation flying because it will provide improved space science and offer more flexible mission architectures. The technologies being developed to perform formation flying can be used in many other applications, including autonomous farming, "smart highways," and "free-flight" of aircraft.

The primary challenges of formation flying are to maintain constant and precise measurements of the relative vehicle states (navigation) and then to apply immediate adjustments (real-time control) to the spacecraft motion to meet stringent performance requirements while preserving fuel. Previous attempts to perform formation flying have been limited by the lack of a sensing system (both hardware and algorithms) that provides precise measurements of the relative positions of the vehicles in the fleet. Our research has developed a novel end-to-end sensing approach based on rigorous theory, architectural innovation, component development, and complete system demonstration.

As part of this research, we have designed and validated a new concept for a carrier-phase differential GPS (CDGPS) sensing system to perform very precise autonomous relative navigation (position, velocity, and timing synchronization) for multiple spacecraft. We also developed techniques to decentralize these estimation algorithms, which greatly improves the robustness and flexibility of the overall approach. Our work has pioneered the development of an augmentation to the CDGPS relative navigation using local radio-frequency ranging between vehicles to improve navigation accuracy and to help initialize the relative navigation. We have also designed two actively controlled microsatellites for a mission called Orion, which should provide the first demonstration of true formation flying on-orbit. Recent ground tests of the OrionGPS flight hardware yielded the best relative position (≈1.5 cm) and velocity (≈0.3 mm/s) errors reported to date for this low Earth orbit application.

In the process of focusing on the formation flying control problem, we have identified two previously unrecognized sources of error (velocity noise and reference orbit eccentricity) that can have a significant impact on fuel cost. We also derived techniques to compensate for these errors in the formation control design. Our research provides a new approach to the coupled problem of high-level fleet control and low-level spacecraft trajectory optimization using Mixed-Integer Linear Programming (MILP), which provides the globally optimal solution to this complex optimization problem.

These estimation and control algorithms have been demonstrated on a high-fidelity simulator of the orbital dynamics, and they are currently being coded into the Orion flight computer. We are still negotiating for a launch date for Orion.

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Spacecraft Autonomy

Model-Based Embedded and Robotic Systems

We are developing a new paradigm for rapidly creating collections of long-lived, robotic explorers that reason quickly, extensively, and accurately about their world. These explorers are prototyped rapidly through an approach we call model-based programming. Model-based programming involves specifying commonsense models of the goals that the explorers should achieve, models of their internal mechanisms, models of how things might go wrong, and models of the world in which they interact. To respond correctly in novel, time-critical situations, these systems depart from conventional artificial intelligence (AI) wisdom, using their onboard models to perform extensive deductive reasoning and planning within fractions of seconds. They will need to embody the resourcefulness exemplified by humans during the Apollo 13 crisis—reasoning from common sense to quickly diagnose the source of anomalous events and quickly responding by exploiting all available assets in a novel manner. In the future, these model-based autonomous systems will be composed of large webs of vehicles that work in coordination to achieve complex space, air, or land missions. Finally, to achieve longevity these robots will need to learn and adapt, automatically elaborating their commonsense models into quantitative models that support high-performance diagnosis and control.

Model-Based Reactive Programming and Control of a Mission to Mercury

In May of 1999, working with NASA's Jet Propulsion Laboratory and Ames Research Center, we demonstrated Remote Agent, a model-based autonomous system that was able to navigate the NASA Deep Space One probe through a wide range of failures. Remote Agent accomplished this by quickly reasoning from a set of commonsense models of hardware and operations knowledge to achieve and track a set of high-level goals. This involved autonomously planning and executing a complex set of maneuvers, monitoring and diagnosing failures, generating and executing repairs, and replanning mission sequences.

In the future, a likely showstopper for widely deploying this level of autonomy is the myriad of AI modeling languages Remote Agent employed and the corresponding expertise required to implement the functions of planning, task decomposition execution, commanding, diagnosis, and repair. Using these systems is difficult and clumsy, and it is analogous to using early operating systems and languages.

We are currently developing a new paradigm that hides these powerful deductive capabilities under the hood of a modern reactive programming language. We start with a language similar to Esterel that embodies such classical concepts as concurrency, preemption, procedural encapsulation, objects, and polymorphism. We gracefully extend this to another language, called the Reactive Model-Based Programming Language (RMPL), that is able to model uncertain effects, hidden state, time, redundancy, and utility of action. The interpreter for RMPL will reason from this knowledge and sensor information on the fly in order to flesh out program details, diagnose novel situations, and generate contingencies where needed. During 1999 and 2000 we performed the initial design of the RMPL language. We also developed an algorithm, called conflict-directed A*, that supports logical reasoning and optimal decision making in real time. Finally, we began the development of algorithms built on top of conflict-directed A* for monitoring, diagnosis, and high-level planning.

We are currently exploring the deployment of RMPL on NASA's Messenger mission to Mercury, currently under development at the John Hopkin's University Applied Physics Laboratory. At the beginning of the mission, RMPL will perform simple onboard monitoring and diagnostic tasks. As the mission matures, RMPL's planning capabilities will assist ground crews in the operation of Messenger.Finally, after a year of mapping Mercury's surface, it is our hope that RMPL will allow Messenger to become fully autonomous, offering a sentinel for unforeseen science events.

Model-Based Planning of Cooperative Air Vehicles

In the future, webs of unmanned air and space vehicles will act together to robustly achieve elaborate missions within uncertain environments. Achieving this robustness will require continuous coordination between intelligent autonomous agents. Autonomously controlling a single vehicle requires methods that reason extensively through system interactions in order to robustly manage the internals of a vehicle. The movement toward webs of vehicles introduces an additional layer of reasoning involving intervehicle communication, coordinated image recognition, asset reconfiguration, formation flying, commanding, and response to contingencies.

We are extending the model-based programming paradigm to the creation of cooperative autonomous agents that are able to create and adapt coordinated mission plans on the fly by reasoning extensively from models of their constituents, collaborators, and pursuants. During the past year we developed the Activity Modeling Language (AML), which extends model-based programming to allow for the expression of complex concurrent behaviors, metric time constraints, and multiple contingencies. Next we created the Temporal Planning Network representation, a compact encoding of AML models that supports efficient planning. Finally, we implemented a centralized planning system, called Kirk, which draws from the techniques of network search, conflict resolution, and hierarchical decomposition to perform rapid multiple-vehicle mission planning. The Kirk system was demonstrated in simulation to perform a coordinated search and rescue mission. In future years, Kirk will be extended to perform high-speed, decentralized planning and coordination.

Coordination and Control of Multiple UAVs via Mixed-Integer Linear Programming

We have developed a new approach to trajectory optimization for autonomous aerial vehicles performing large-scale cooperative maneuvers. The main result is a receding horizon trajectory planner based on Mixed-Integer Linear Programming (MILP) that optimizes trajectories to a goal in an environment constrained by nonconvex no-fly areas. MILP is well suited to this application because it can directly incorporate logical constraints such as obstacle avoidance and waypoint assignment and because it provides an optimization framework that can account for basic dynamic constraints such as turn limitations. However, applying MILP with a fixed planning horizon is not suited to real-time control because the computational effort required grows rapidly with the length of the route to be planned and the number of obstacles to be avoided. We show that this limitation can be avoided by using a receding planning horizon in which MILP is used to form a shorter plan that extends toward the goal but does not necessarily reach it. The key in this case is to develop a good approximation of the cost-to-go from the plan's end point, accounting for decisions required to reach the goal that are beyond the planning horizon. We have developed an approximation that accurately estimates this cost-to-go and provides an efficient linkage of the two parts of the trajectory.

This trajectory design approach has also been extended to include robustness to bounded disturbances and to ensure a priori that the vehicle trajectory is safe even with only limited knowledge of the environment. The MILP approach has also been used to extend a recently developed "maneuver automaton" approach to trajectory design. Our new formulation to this problem uses a model that consists of both linear time invariant (LTI) modes and some aggressive maneuvers for rapid changes between the LTI modes. Trajectory optimization for the new class of models can be directly cast as a MILP, wherein the binary decision variables are used to characterize the options of staying in an LTI mode or of executing an aggressive maneuver.


The first test bed uses multiple rovers and blimps.

The second test bed has six small unmanned aerial vehicles.

Future plans include demonstrating this combination of activity and trajectory planning of multiple vehicles on our two new test beds funded by the Defense University Research Instrumentation Program (DURIP). The first test bed uses multiple rovers and blimps operated indoors to emulate a heterogeneous fleet of vehicles that could be used to perform a search and rescue mission. The second test bed has six small unmanned aerial vehicles (UAVs) that are flown autonomously using a commercially available autopilot. Small aircraft (RC-sized trainers) were purposely chosen for this test bed to reduce the operational complexity while still providing a high degree of flexibility in the missions that can be performed. These test beds are being used to demonstrate several recent advances in the cooperative path planning and team task assignment components of the overall control architecture. Working with these test beds will highlight the fundamental challenges associated with (1) planning for a large team in real time, (2) developing controllers that are robust to measurement errors and uncertainty about the environment and sufficiently flexible to respond to dynamic changes, and (3) using communication networks and distributed processing to develop integrated and cooperative plans.

Model-Based Hybrid Health Management and Control of a Martian Habitat

Recent failures of space missions, such as the Mars Climate Orbiterand the Mars Polar Lander, might be avoided in the future with capable model-based health management and autonomy capabilities. However, while existing model-based reasoning techniques use discrete, qualitative models, these recent incidents involve subtle failures that require additional quantitative models in order to diagnose and compensate for their causes. We call the mix of discrete and continuous behaviors a hybrid model. We are developing a new generation of hybrid health management and control capabilities that unify symbolic, model-based reasoning methods with methods for model-based state estimation and control. During the past year, we began the development of methods for learning the parameters of hybrid models that merge discrete automata with ordinary differential equations. In future years we will extend these methods to high-fidelity monitoring, diagnosis, and control synthesis. These methods are being developed to control and monitor the health of Bioplex, a test bed at NASA's Johnson Space Center that simulates a Martian colony.

Space Power and Propulsion

The Space Propulsion Laboratory (SPL), part of SSL, focuses on the interactive problems related to the propulsion and power-generating systems of spacecraft. The propulsive activity has dominated recently and has continued to center on various aspects of electric propulsion and its mission applications.

We have extended our existing numerical simulation model of the plume of Hall thrusters by including the possibility of nonneutral regions, as can occur around high-altitude plumes. The rectangular grid has been replaced by a more versatile tetrahedral grid that can be automatically generated from a triangular surface grid representing complex objects, such as a complete spacecraft. The whole code (now called AQUILA) is written so as to interface directly with a broader, user-friendly computational environment (COLISEUM) created by the Air Force Research Laboratory for General Spacecraft Interaction Studies. Doctoral students Shannon Cheng and Murat Celik and master's student Mark Santi are active in this program.

A new and more advanced simulation code for Hall thrusters—in which electrons as well as heavy particles are treated as dynamic entities and moved in accordance to self-consistent electric fields—is being readied by J. Szabo (PhD candidate). This will shed light on ionization, electron transport, and wall-plasma effects in these devices. The code is being used by master's student Kay Sullivan for a study, supported by NASA Glenn Research Center, of the operation of Hall thrusters at high voltages and with more than one acceleration stage. Concurrently, MS student Noah Warner has been performing for verification internal Langmuir probe studies on a high-voltage thruster at Busek Company.

Doctoral candidate T. Onishi completed his doctoral thesis on a numerical code to compute the performance of bare metallic tethers as electron collectors in space. The model was later extended and refined by Jean Benoit Ferry is his master's thesis. This bare tether concept, originated at our laboratory, is being implemented as the basis for ProSeds, a flight mission in preparation by NASA's Marshall Space Flight Center, and an extension to flat-tape geometry is being applied to a MIR station reboost project.

As a result of our scaling studies of electric propulsion, we have advocated a revival of colloidal propulsion technology for use in microspacecraft and have formed an informal alliance with industry (Busek Company) and Yale University for this purpose. Our studies (sponsored by the Air Force Office of Scientific Research, NASA, Draper Labs, Connecticut Analytical, and Lockheed-Martin) show this to be a very promising micropropulsion avenue for the future. We have developed a complete formulation of the physical model characterizing the operation and performance of colloidal thrusters in the pure droplet regime (Jorge Carretero). Results compare very well with experiments and reveal the reason for the existence of two different subregimes, depending on the liquid's dielectric constant. Our small-dedicated vacuum facility for colloidal studies was used by Paulo Lozano (now a postdoc in the laboratory), in his PhD thesis to perform accurate time-of-flight mass spectroscopy on sprays of various fluids in the droplet, mixed droplet/ion and pure ion regimes. Doctoral student Luis F. Velasquez is finalizing the process of creating a microfabricated cluster of 250 colloid thrusters on a silicon chip; since each of them provides submicro Newton thrust, these arrays hold great promise for high-precision spacecraft. In addition, we plan on extending the work to two-dimensional dense arrays of emitters, aiming at the application to primary propulsion for small spacecraft. Studies are also underway on using capillarity for wick-type feeding of the liquid and on operating bipolar arrays to obviate the need for an electron emitter for neutralization (MS student José M. López-Urdiales).

A new propulsion facility has been established with funding from DURIP. The facility includes two new vacuum chambers, nicknamed AstroVac II and MiniVac, on the 4th floor of Building 37.


Astrovac chamber.

AstroVac is intended for studying small Hall thrusters or other ion engines. The chamber is a large cylinder, 1.4 m in diameter and 1.6 m long, with two cryogenic pumps, which produce a pumping speed of 7000 l/s of Xenon. During regular thruster operation, the vacuum chamber is expected to achieve a pressure of 2x10-5Torr. There are six windows and numerous ports for electrical, water, and gas feedthroughs. Graduate students will be able to develop instruments and run experiments on thruster plasma plumes (exhaust). The facility also has a thrust balance used for determining thruster performance. Hall thrusters are currently a hot research subject as they are being considered for various commercial uses, but they remain much less understood than familiar chemical engines.

This facility has already been used by master's students Stephanie Thomas, Anne Pacros, and Yassir Azziz to perform plasma plume measurements on a small Hall thruster (BHT-200), on loan to the laboratory by Busek Company. The May 2003 thesis by Y. Azziz shows very detailed explorations of the plume with Langmuir, Faraday, and emissive probes, mounted on an automated motorized arm that was built by UROP students. The data are clean and consistent and correlate well with our theoretical models.


MiniVac.

MiniVac, installed in September 2000, is used primarily for research on colloid thrusters. This facility is quite small—just 8 inches in diameter. Equipment for this chamber includes a microscope and a set of electrostatic lenses and collimators that can be reconfigured in various ways for basic physical studies of colloid and ion beams.

With funding from Loral Aerospace, master's students Scott Kimbrel and James Whiting have developed a powerful tool for optimization of mixed impulsive–low thrust missions to place spacecraft in geosynchronous orbit.

Wesley L. Harris
Department Head
Charles Stark Draper Professor of Aeronautics and Astronautics

More information about the Department of Aeronautics and Astronautics can be found on the web at http://web.mit.edu/aeroastro/www/.

 

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