THE ROLE OF UNIVERSITIES IN SMALL SATELLITE RESEARCH

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1 THE ROLE OF UNIVERSITIES IN SMALL SATELLITE RESEARCH Michael A. Swartwout * Space Systems Development Laboratory 250 Durand Building Stanford University, CA USA 27 August, 1997 ABSTRACT The investigation of fundamental scientific problems is a core mission of the university. Professors and researchers have had a long, successful history as principal investigators for such projects. Now, because technological advances have made small spacecraft less expensive and more capable, universities can offer their services in the area of spacecraft design and development as well. This is not a call for students to build and operate high-performance spacecraft. Rather, it is an announcement of opportunity for universities to apply their strengths education and innovation to a new field. For the research and teaching process which universities use to contribute to scientific investigation also equips them to contribute to spacecraft engineering. Students and professors can take risks, make mistakes, and learn from them, allowing them to try out wild ideas in search of helpful lessons. The university environment allows research and study in new methods of spacecraft design, fabrication and operation - at lower costs and with more acceptable risk than is possible in industry. There is also a valuable byproduct: knowledgeable, capable students seeking employment. Experience in two Stanford satellite projects, Sapphire and Opal, confirms these assertions. Sapphire has demonstrated the feasibility of space-based alternatives to standard ground-based testing of new components. Opal has provided researchers with an alternate mission architecture that has justified a new project at the Jet Propulsion Laboratory. These spacecraft, and the others that will be developed at Stanford, contribute to the training of students in spacecraft systems engineering, and help demonstrate new technologies and processes. Such contributions are necessary elements in the effective use of small spacecraft. INTRODUCTION Successful scientific investigation is founded on "hypothesis and test" approach; a scientists presents a possible explanation for a physical process, which has certain effects that are predictable and testable. The scientist performs the test in his or her laboratory, confirming or * Doctoral Candidate, Aeronautics & Astronautics

2 rejecting the hypothesis. Often, the results of the test give new information leading to new hypotheses. This is no different with science conducted from small spacecraft. What makes this particular approach challenging, however, is the complexity and cost involved in creating and maintaining an orbital platform. While ground-based experiments can be personally monitored, adjusted, and re-started as necessary, it is no easy task to retrieve and fix a satellite. Thus, risk management becomes a dominant issue in developing space-based scientific experiments. Often, it is the cost, complexity and risk of the enabling technology, not the science, that limits the use of spacecraft for experiments. Risk can be alleviated by bringing universities into partnerships with professional spacecraft enterprises. Universities are specially equipped to accept the challenges inherent in such projects. Their focus on education and innovation not only allows universities to participate in the development of the science payloads, but also equips them to further the technologies and processes involved in all aspects of building spacecraft. As the cost of space-capable electronics continues to decrease and the capabilities of these components continues to increase, students can actively contribute to more areas of the spacecraft industry. This paper describes the strengths of weaknesses of the university in the context of developing small spacecraft for scientific pursuits. Recommendations are made for including students and researchers in the spacecraft process, thereby reducing costs while increasing the performance of the space missions. Examples from the projects at Stanford's Space Systems Development Laboratory (SSDL) are used to illustrate these points. THE LUXURY OF FAILURE The advantages universities bring to spacecraft development can be summed in one word: failure. Students have the "luxury" to fail, something that most in professional space industry must avoid. In fact, failing and learning from failure are some of the most important parts of a student's education. Students in a university setting are encouraged to seek out innovative (and therefore often risky) approaches to solving problems. By taking risks and comparing their results with standard methods, the students gain insight into the underlying phenomena and have a better appreciation for accepted practice. They develop habits of identifying and challenging the assumptions used in solving problems. "Encouraged failure" trains students to learn from their mistakes. And of course, sometimes students discover new and exciting solutions to problems that once were thought to be unsolvable. By emphasizing their role as educators, training the next generation of spacecraft engineers and scientists, universities are well-suited to contribute to the development of spacecraft for scientific studies. If "mission success" from the university's standpoint is defined as students who have been well-prepared for careers in the space industry and researchers who have been given the opportunity to study challenging problems, then the success or failure of the project in question is of secondary importance. A university can fully accomplish its goals with a project that does not work as planned or never even leaves the ground!

3 This is not to say that universities should only seek out the projects that cannot work or an excuse to put forth only the minimum effort to satisfy their educational needs. The luxury of failure is a freedom to allow universities to seek out new, innovative, and risky projects. Such ventures provide maximum challenges and opportunities for their students and researchers, and is a direct way for the university to contribute to projects that otherwise could not risk getting started. And, as is the case for all student investigations, sometimes these risky, wild ideas produce magnificent results. EXAMPLES FROM SSDL PROJECTS The Space Systems Development Laboratory (SSDL) at Stanford University was chartered in 1994 to promote basic research in all areas of spacecraft design, fabrication, and operations. Part of its charter is fulfilled in the Satellite Quick Research Testbed (SQUIRT) program [1]. This is a year-long project that takes students through all aspects of building and operating spacecraft. Work on the first two SQUIRT satellites, SAPPHIRE and OPAL, has begun in earnest, and additional studies have been undertaken in the areas of spacecraft operations and autonomy. During its young existence, SSDL has already demonstrated that the university's strengths of education and innovation enable it to contribute to space-based scientific pursuits. SAPPHIRE [2] was started in March of It is a completely student-designed, student-built, and student-operated microspacecraft. Its seven missions include the first flight of a nextgeneration horizon detector, an on-board fault detection autonomy experiment, and other basic research in spacecraft operations. SAPPHIRE is undergoing final environmental testing and will be ready in early 1998, at a total out-of-pocket expense of less than $50,000. In addition to educating some seventy-five students, several of whom have already taken prominent positions in the space industry, SAPPHIRE is opening the door to the use of student satellites for space research. The horizon detectors, developed by Professor Tom Kenny of Stanford, take advantage of new micromachined technology to place the entire sensor on a computer chip, making it a very small, room-temperature infrared sensor. The developers' limited resources effectively restricted testing of this space sensor to the ground until a low-cost option like SAPPHIRE became available. The contributions of OPAL are similar yet, in some ways, more significant. OPAL [3] started in March of 1995 with a main payload funded by the same sources as SAPPHIRE. The Jet Propulsion Laboratory (JPL) was interested in developing a new technology for deploying hundreds of extremely small sensors over a wide range to study the Earth's magnetic field. OPAL demonstrated a feasible design to launch many hockey-puck sized objects from a very small (16" from tip to tip) spacecraft. Partially due to the efforts of the OPAL team, JPL has created a fully-funded office to further develop this technology. OPAL is an unusual example of a project that fulfilled its project goals before the satellite launched! OPAL's flight hardware is currently being integrated and will be undergoing environmental testing in the fall of In each case, ideas that were judged to be too risky or having too little payoff were given new life by investing a small amount into student projects. And, in each case, the students'

4 contributions paved the way for future studies by others in the spacecraft industry. Such results are possible for any organization willing to "risk" investing in university projects. PROPERLY DEFINING THE UNIVERSITY'S ROLE Yet despite its obvious benefits, the university is not the "magic solution" to all the challenges of small spacecraft development. Universities cannot and should not be used to create low-cost "state of the art" satellites. Not only does this exceed the charter and scope of academic pursuits, but the professional spacecraft industry is much better equipped to face the demands of developing capable spacecraft. Often, it is mistakenly assumed that low-cost graduate students can match the performance of full-time professionals; the result usually is a mission that runs years behind schedule, if it is ever finished at all. The success of the SAPPHIRE and OPAL projects is largely due to the proper scope of the problems under investigation. Each spacecraft is being used to address a few, clearly-defined questions. Solving these problems is within the capability of these students; it is their unusual and/or high-risk nature, not their complexity, that makes the professional industry uninterested in studying them. The results, however, are of significant interest, and have proved to be of great value to other programs. The university contributes best to spacecraft development when it is in partnership with industry and government, each adding its strengths to the overall project. With its "luxury of failure", the university provides opportunities for low-cost investigation of risky and/or innovative methods. Government and industry can sponsor student investigations for a fraction of the cost to study it in-house. In return for such investments of resources and support, the university also produces its most valuable resource: trained, capable students, ready to enter the spacecraft industry. ACKNOWLEDGEMENTS The author wishes to thank his fellow students in SSDL, especially Chris Kitts for his willingness to discuss these sort of issues. Appreciation is offered to the design teams of the OPAL and SAPPHIRE projects for their long hours and dedication. Thanks are also due to Professor Robert Twiggs for sliding deadlines in order to complete and present this paper. This work has been performed in partial satisfaction of graduate studies at Stanford University. REFERENCES [1] Kitts, Christopher A., and Robert J. Twiggs, The Satellite Quick Research Testbed (SQUIRT) Program, Proceedings of the 8th Annual AIAA/USU Conference on Small Satellites, Logan, Utah, Aug Sept. 1, 1994.

5 [2] Lu, Richard A., Tanya A. Olsen, and Michael A. Swartwout, Building Smaller, Cheaper, Faster Satellites Within the Constraints of an Academic Environment, Proceedings of the 9th Annual AIAA/USU Conference on Small Satellites, Logan, Utah, September 19-22, [3] Engberg, Brian, Jeff Ota, and Jason Suchman, The OPAL Satellite Project: Continuing the Next Generation Small Satellite Development, Proceedings of the 9th Annual AIAA/USU Conference on Small Satellites, Logan, Utah, September 19-22, 1995.