Neutral Buoyancy/Parabolic Flight Habitat Studies

Transcription

1 exploration Habitat (X-Hab) 2014 Academic Innovation Challenge Neutral Buoyancy/Parabolic Flight Habitat Studies Dr. David L. Akin Associate Professor of Aerospace Engineering Director, Space Systems Laboratory Department of Aerospace Engineering James Clark School of Engineering University of Maryland Institutional Member of the Maryland Space Grant Consortium Space Systems Laboratory University of Maryland University of Maryland! Page 1

2 Neutral Buoyancy/Parabolic Flight Habitat Studies The University of Maryland (UMd) Department of Aerospace Engineering and Space Systems Laboratory (SSL) is pleased to submit this proposal to the the National Space Grant Foundation and the NASA Human Exploration and Operations Mission Directorate for Neutral Buoyancy/ Parabolic Flight Habitat Studies, for the X-Hab 2014 Academic Innovation Challenge. Dr. David L. Akin, Associate Professor of Aerospace Engineering and Director of the Space Systems Laboratory, will serve as the Principal Investigator and lead faculty instructor for this activity. The University of Maryland is ABET accredited, and a member of the Maryland Space Grant Consortium. Proposal Synopsis Under the 2014 NASA X-Hab Academic Innovation Challenge, the University of Maryland Space Systems Laboratory will perform testing of habitat layouts and individual work station designs in the UMd Neutral Buoyancy Research Facility. This will include assessments of habitability, mobility in both microgravity and partial (lunar and Martian) gravity, and functionality of work station designs and restraint systems. Although we feel that neutral buoyancy investigation of habitability is a rich area of research which could profitably consume all of the resources allocated through the X-Hab 2014 program, we will also seek other funding (such as the NASA Reduced Gravity Flight Experiment Program) to support correlative testing in parabolic flight as a target of opportunity. This project will be used as impetus for academic projects at the freshman (ENAE 100), undergraduate (ENAE 398H, ENAE 483/484, and ENAE 488R), and graduate (ENAE 788D) levels. Undergraduates will be mentored by faculty and graduate students while designing and fabricating components of both a low-fidelity habitat simulator, and a higher-fidelity work station, for use in the UMd Neutral Buoyancy Research Facility.. These components will be extensively tested in the University of Maryland Space Systems Laboratory, and will be able to take advantage of existing research systems in the SSL including high-resolution underwater motion tracking cameras for documenting body motions throughout the tests. Significance The University of Maryland, particularly the A. James Clark School of Engineering, has a long and rich history of student design and development projects. Our curriculum is based on student team-based hands-on projects throughout the curriculum, from the first Introduction to Engineering class to the required senior capstone design courses. In addition, UMd has fielded a large number of highly successful teams in student design competitions, from concrete canoes and alternative fuel vehicles to autonomous underwater vehicles and advanced robotics. While Aerospace Engineering students in the Aeronautical track have always had the opportunity to participate in design-build-fly challenges, X-Hab is one of the first externally sponsored design activities which support design-build- fly (actually design-build-test-evaluate) for our students in the Space track. The immediate significance of this proposed research to NASA is that it addresses significant issues in the NASA Technology Roadmap for TA06 (Human Systems) and TA07 (Exploration Systems); specifically, (Habitation) and (Habitation Evolution). Both of these were in University of Maryland! Page 1

3 the top priority category as rated by the National Research Council review, and in fact habitats were second only to radiation as the top-priority issue for the Human Systems area. The long-term significance to NASA is that the X-Hab Competition will serve as an excellent motivator for students in engineering majors, as well as support additional opportunities for the students to move beyond classical lecture/homework/exams class structures to hands-on design activities. Our experience, which is supported by engineering design faculty across the nation, is that giving students opportunities to get dirty with the creation and testing of real hardware systems acts as an amplifier of their classroom instruction, and in fact motivates a body of students whose learning styles are much more attuned to learning by doing. Content The University of Maryland is uniquely qualified to propose to this topic, as the Space Systems Laboratory is based at the Neutral Buoyancy Research Facility (Figure 1), one of one two active neutral buoyancy facilities in the U.S. and the only one in the world located on a university campus. The NBRF water tank is 50 ft. in diameter and 25 ft. deep, providing nearly 1400 cubic meters of test volume. This facility has been used extensively over its 21 years of existence for simulation of microgravity for investigations in both human and robotic operations in space. The SSL has also developed detailed protocols for testing partial gravity environments underwater by body segment ballasting, as shown in Figure 2. This figure also shows the unique instrumentation installed in the water tank, as 12 motion tracking cameras provide sub-centimeter position resolution for an effectively unlimited number of reflective optical targets at greater than a 20 Hz update rate. This capability allows us to propose tests which monitor not only test subject motions, but body pose and individual limb motion during all activities, including translation or operations at a fixed work station. We propose to perform two levels of testing in this X-Hab activity. The first is gross motion, such as moving around a habitat mockup in various gravity environments. We propose to develop and build a low-fidelity mockup of HAVEN for the water tank, to allow direct correlations between tests with the unit in the Moonyard in 1g and identical protocols in microgravity, lunar, and Mars gravity conditions in the underwater unit. The test subject will be breathing off of a hookah rig to Figure 1 - UMd Neutral Buoyancy Research Facility (NASA Hubble Space Telescope mockup in tank) Figure 2 - Lunar gait research in NBRF (motion capture cameras are bright lights in image) University of Maryland! Page 2

4 avoid the inertial complications of a back-mounted air bottle, and using a full face mask to allow two-way unlimited voice communications for running assessments and safety purposes. In parallel, the SSl will perform fine-scale motions of humans at a work station, looking at the optimal design of the work station and associated restraints as a function of gravity level. Again, the motion capture system will provide details on, for example, how neutral body posture varies between the two well-known cases of microgravity and Earth gravity. Prior to the start of the team s activities, the principal investigator and lead graduate student will develop a set of Level 1 requirements and a top-level schedule, centering on regular milestones. It should be noted that there are significant issues associated with underwater simulation, ranging from the critical aspects of safety to best practices on materials choices, fastener selection, and capabilities of support divers to perform extended work underwater. It will be essential to the success of the proposed program to have a highly experienced SSL graduate student involved on a day-to-day basis to monitor and advise the X-Hab team members on the feasibility of their concepts. Based on past experience, the ideal arrangement is to have evolutionary milestones every two-three weeks, to make sure that continual progress is being made on the project. Major milestones will subsume the listed milestones in the solicitation, as well as other arranged activities such as the biweekly tag-ups of the 2011 X-Hab program. The first section of ENAE 483 (Principles of Space Systems Design) covers the tools and techniques of systems engineering, with particular emphasis on NASA practices and standards. ENAE 483 students working on X-Hab will start with the provided Level One requirements and schedule, and work to create a detailed work breakdown structure (WBS), a multilevel requirements document with traceability of requirement flow-down from Level One, and a detailed schedule for the year-long project which incorporates the faculty-provided high-level schedule. At this time, the team will also start to develop a parts list, drawing list, and document archive to ensure that all X-Hab design product is captured and indexed for easy location by all team members. The ENAE 483/484 design course in the past has had excellent results using TRAC, an open-source program management system which includes a wiki, document and software management (using Subversion, an open-source archiving program), a timelining program to track progress in real time, and a ticket system for assigning and tracking action items. The establishment of the Systems Engineering formal structure for the X-Hab project, along with the initial strawman habitat design, will be the focus of the Systems Requirements Review, which will be conducted at the end of September, 2013, via telecon and Webex to NASA and NSGF reviewers. We also have an established group of professionals in the DC area who serve on 483/484 design review panels each year, and we intend to invite them to sit in on X-Hab reviews as well. During this month, the team will decide on the basic structural concept for the neutral buoyancy habitat mockup, focusing on structures which are easily assembled and reconfigured, and constructed of nonmetallic material to stand up to long-term exposure to the chlorinated water of the tank. Design will also take place on the canonical work station design, drawing from experiences with past microgravity and Earth work station designs. Prototypes of the workstation test stand will be performed ENAE 100 project teams, mentored by the X-Hab faculty and research assistant. ENAE 398H volunteers will work with the faculty to identify higher-level goals for their individual research, such as the use of existing SSL underwater University of Maryland! Page 3

5 dexterous manipulators to provide force reflection to the human operator, both to simulate the use of haptic devices in the space habitats and to provide known perturbation forces in analysis of subject postural responses to controlled impulses. By the Preliminary Design Review at the end of October, the team will have initial results from the prototype evaluations, and a more detailed baseline design for the underwater habitat, including an initial concept for simple reconfiguration of the habitat interior underwater. Concept configuration drawings will be produced, such as SolidWorks, Creo, or NX. Material in the PDR, including tracking performance against the formally established program plan, will be presented for review. The result of the PDR should be sufficient clarity of design to justify the purchasing of long-lead items. Continued design and testing activities will lead to the Critical Design Review at the end of November. The design process will focus on the design of the workstation mockup to accommodate reconfiguration of both the work station envelope and the location and orientation of foot restraints to provide subject body stability in microgravity conditions. At the same time, detailed fabrication and assembly drawings will be nearing completion for the underwater habitat mockup. Production drawing sets should be 95% complete at this point, and a successful CDR will justify the release of funds for purchasing all materials and components necessary for production and testing of the full-scale X-Hab. The goal for December is to ensure that all necessary parts are ordered, and any open items remaining from the CDR are closed out. Experience indicates that due to fall term finals and the end-of-year holidays, December work productivity in academic projects is considerably depressed as compared to the average. At UMd, January is a mid-winter break period, with spring classes starting at the beginning of February. January is therefore an excellent month for research progress, and X-Hab volunteers returning early from break will be encouraged to start the fabrication and assembly of the fullscale habitat and work station. The overriding concept for the habitat and work station mockups, based on decades of SSL experience with long-duration underwater mockup hardware, is to minimize the use of metal structural components, and maximize the use of long-term stable inert materials such as fiberglass, acrylic, and other polymers. With the completion of the base structure from fiberglass extrusion elements, the students can start to construct the habitat shell. There are four basic approaches to the structural elements: rigid fiberglass sheet will be used for floors and fixed walls, acrylic sheets can substitute for fiberglass in areas where visibility is essential for safety or data collection, urethane-coated nylon material is well-suited to temporary (non-loadbearing walls and ceiling structures, and neutrally buoyancy polyethylene netting is an excellent choice in regions where ventilation is necessary to prevent the capture of bubbles, such as those from underwater breathing apparatus located under a ceiling or overhang. A significant focus of the design process will be to carefully pick the right material for each application area of the habitat. With the completion of the habitat, initial underwater tests will begin at this point to verify data collection protocols and adequacy of viewing for the motion capture cameras, particularly for University of Maryland! Page 4

6 activities inside the habitat mockup. All this leads into the first progress review, around the middle of February. Efforts throughout the spring 2014 term will primarily focus on testing with the full-scale habitat and reconfigurable work station. Tests will initially be performed in microgravity simulations; later refinements will include comparative testing with subjects ballasted to simulations of lunar and Mars gravity. This will provide original and invaluable data on mobility within a habitat at various gravity levels, and will inform a much better concept of how habitat design needs to change between destinations. Mechanisms for Integration Rather than conduct the X-Hab activity within a single design course, we propose to establish an innovative structure for the activity, allowing us to draw a more diverse set of students from a number of other courses. The core of the X-Hab design team will be drawn from ENAE 483/484, the year-long senior capstone design course in spacecraft design. Students in ENAE 483/484 are given specific instruction in Systems Engineering tools and techniques as practiced at NASA, along with lectures and problem sets in Systems Analysis; Mission Planning and Analysis; Loads, Structures, and Mechanisms; Power, Propulsion, and Thermal; Crew Systems and Habitability; and Avionics. These students are seniors in Aerospace Engineering, and have all of the disciplinary courses of Aerospace Engineering in their background. The entire class (39 students for the academic year) are formed into a single design team to address the design of a major aerospace system. Design topics in recent years have focused on lunar infrastructure items, such as pressurized rovers and lunar flying vehicles. These topics are selected to allow a substantial design-build-test-evaluate (DBTE) component, in which the class team actually builds hardware and tests it in support of the overall design activities. We look to the participants from the ENAE 483/484 sequence to be the central focus of X-Hab design, development, and fabrication activities. Rather than limit the X-Hab team to the ENAE 483/484 class sequence, we will also use project teams in ENAE 100 (Introduction to Aerospace Engineering) to help develop and test prototype and production hardware. These teams are typically 5-6 freshmen, who are responsible throughout the term for designing, and building an engineering test, and operating it to collect and analyze data. We will identify several technical design issues from X-Habto help design and test candidate concepts for task hardware and for innovative techniques for obtaining quantitative data from test operations. In addition to the freshman teams, honors students in Aerospace Engineering will participate through the ENAE 398H course, which involves individual experimental research for the Aerospace Honors program. Specific design projects, such as a detailed structural analysis of the underwater habitat, will be performed by honors students (typically in their junior year) who wish to participate in the X-Hab project. The University of Maryland is submitting several proposals for the 2014 X-Hab Academic Challenge. While each is a stand-alone research proposal, there is significant synergy in combinations of proposals that might be jointly funded. Most significantly, the proposal for vertical habitat layout assessments would provide direct correlation of the results from this University of Maryland! Page 5

7 proposal in terms of mobility and layout assessment for the HAVEN (5-meter diameter) habitat in the Earth analogue habitat which is continually correlated with underwater results from microgravity, lunar, and Mars gravity simulations. This would be ground-breaking space habitat research as an outcome of the two X-Hab 2014 projects performed in parallel. Diversity As described in the preceding section, we are creating an extended student team for X-Hab, drawing individuals ranging from first-term undergrads to graduate students. This in itself is a dimension of diversity; past experience indicates that the interactions between these groups, particularly the older students mentoring their younger teammates, provides a more cohesive overall team and allows the students to grow in ways other than strict technical skills. The University of Maryland at College Park, as might be expected from a university within the Washington, DC beltway, has a student body which is unusually diverse in race, ethnicity, and national origins; this is the population from which we will draw the overall X-Hab team. We will strive to ensure that the team is a diverse assemblage that encourages members of underrepresented groups to participate fully, such that the team represents not only the diversity of the University of Maryland campus, but that of the society at large. Office of Educational Performance Measurement (OEPM) Reporting Requirements We have participated in OEPM reporting for our activities in the 2011 and 2012 X-Hab competitions, as well as for activities funded by Maryland Space Grant Consortium. This includes tracking all students involved in the program, and reporting names, s, and other information to OEPM for their evaluation activities. Educational Outreach Plan The University of Maryland Space Systems Laboratory has a long history of actively seeking out opportunities for education and public outreach, through laboratory activities and mentoring of student teams. The Space Systems Laboratory, especially the Neutral Buoyancy Research Facility, is one of the most active tour sites on campus, hosting more than 100 tour groups annually with well over 2000 K-12 students. Space systems courses such as ENAE 483/484 have a hard requirement for 100% participation in K-12 outreach; over the years of maintaining this focus, the university has built strong ties with a number of local schools at elementary, middle school, and high school levels. Students participating in this X-Hab activity will be expected to repeatedly participate in K-12 outreach activities, both on campus and at participating schools. The SSL has developed a set of curricula in STEM outreach, emphasizing hands-on activities such as designing vehicles to protect eggs or water balloons in drops from a various heights using only provided materials such as styrofoam cups, drinking straws, and duct tape. Under this project, one emphasis will be on encouraging K-12 students (particularly in younger classes) to design their own space habitat interiors, and to tour the habitats at the UMd Moonyard. Demonstrations at the Neutral Buoyancy Research Facility will illustrate to the students the additional challenges of habitat design for the microgravity environment, or for reduced gravity levels on the Moon and Mars. University of Maryland! Page 6

8 Assessment Plan The University of Maryland School of Engineering for many years led the BESTEAMS ( Building Engineering Student Team Effectiveness And Management Systems ) program for the National Science Foundation, focusing on methodologies for building and maintaining team structures in engineering; Dr. David Akin, the Principal Investigator and lead instructor for this X-Hab proposal, was a participant in the BESTEAMS program, and will adopt a number of their team creation and outcomes assessment methodologies to this project. We will start with documentation of the demographics of students involved in X-Hab, as a metric on the success of our diversity outreach efforts. From the start of the program, we plan to implement an ongoing series of assessment activities throughout and after the completion of X- Hab at the end of the academic year. Using electronic communications through the Canvas interactive communications system in the Clark School of Engineering, participants in the X-Hab Competition will be asked to take an entry questionnaire examining their motivation for participation, expectations for what they will learn, and attitudes towards team projects and the skills necessary for extended collaboration, particularly across grade levels. Online discussion boards with anonymous posting allow ongoing discussions throughout the term, and frequently serve as valuable indications of team morale and suggestion boxes for needed modifications in the faculty administration of the project. This material, along with specific questionnaires and interviews at the end of the project, will be the source for the lessons learned section of the X-Hab final report. All undergraduates in Aerospace Engineering are already interviewed at graduation in support of ABET assessment requirements, and will be questioned during this exit interview on their experiences in X-Hab as a motivating force in their education, and for any impact it may have had on their future career decisions, such as graduate school or which post-graduate job offer to accept. To the extent possible, students are also interviewed (typically by phone) one, three, and six years after graduation to see how their perspective on their education changes with time in their professional careers. Past Performance The University of Maryland is uniquely qualified to conduct a successful entry in the X-Hab Academic Innovation Challenge. The Principal Investigator, Dr. David L. Akin, has taught spacecraft design for thirty years, at both the University of Maryland and the Massachusetts Institute of Technology. He was a member of the National Research Council panel reviewing NASA technology plants in task areas 6 and 7 (Human Systems and Exploration Systems), and thus is fully knowledgeable on the impact of this research on the strategic plans of NASA HEOMD. He was a charter participant in a number of NASA student design competitions, including the University Space Design Program, the Human Exploration and Development of Space - University Partnerships (HEDS-UP), and the Revolutionary Aerospace Systems Concepts - Academic Linkage (RASC-AL) programs. Both undergraduate and graduate teams under Dr. Akin have been highly successful in these design competitions, including first-place finishes in the RASCAL undergraduate category for the last three years in a row. All three of these winning teams in recent years have involved projects with substantial design-build-test content. For example, the 2010 winning entry involved the design, development, and field testing of an astronaut assistance rover, which was demonstrated at the NASA Desert RATS field trials University of Maryland! Page 7

9 in September, Since that time, the rover has been repeatedly used for field trials investigating the effect of advanced robotics on the performance of geological field science in simulated moon and Mars exploration, in a joint program between UMd and Arizona State University sponsored by the NASA Science Mission Directorate. The UMd Department of Aerospace Engineering and the Principal Investigator also have relevant experience in full-scale habitat fabrication and testing, through the NASA ESMD Minimum Functionality Lunar Habitat program. Under this project, the University of Maryland was one of three contractors developing designs for a minimally-functional lunar habitat capable of supporting four crew for a thirty-day nominal stay and sixty-day contingency stay. In addition to the paper studies, the University of Maryland developed a full-scale habitat mockup for use in human factors assessments of interior layout. Given Dr. Akin s nearly forty years of experience in human space flight, both in academia and at NASA, the University of Maryland team has not felt it to be a high priority to identify a NASA technical mentor for this team. The Space Systems Laboratory has a long and productive history of close collaboration with NASA, especially with the NASA technical experts in habitat design and space architecture, and looks forward to continued interaction with them throughout the course of this proposed research. Resources (Sponsors) The budget indicates that we can successfully complete the X-Hab challenge within the $48,000 award value, based on the University of Maryland s agreement to reduce overhead costs and careful attention to cost containment. To add margin to the system, particularly in regard to having the ability to bring a larger number of students to JSC to participate in the June demonstrations, we have requested additional funding from the Maryland Space Grant Consortium and the A. James Clark School of Engineering Minta Martin Endowment. The decision dates on both of these proposals are after the deadline for submission of this proposal. Both funding sources have been generous with student projects in the past; the Maryland Space Grant Consortium, in particular, was the primary funding source for the winning RASC-AL student design entries described in the Past Performance section, above. Although we feel confident we can fully execute the proposed program without additional funding, success with these proposals will provide approximately $10K of additional funding to support and enhance the X-Hab development and demonstrations. University of Maryland! Page 8

10 Schedule Month Activity Summary Milestones September 2013 Program kick-off Development of Level 1 Requirements Development of Requirements Document Development of Work Breakdown Structure Initial strawman design concept Detailed program plan/schedule Systems Requirement Review October November December January 2014 February March April May June Structural analysis Materials selection process complete Prototype component fabrication underway Trade studies complete Completion of prototype design drawings Pathfinder testing of motion capture protocols Prototype full-scale test components All long-lead parts on order Start fabrication of full-scale components Pilot tests of protocols for habitat and workstation Installation of underwater habitat mockup Ongoing underwater tests of habitat and workstation Modifications to test hardware reflecting lessons learned to date Continuation of test operations Completion of nominal test operations Additional tests for missing data points or to examine interesting results Final and submission of the final report Preliminary Design Review Critical Design Review Progress Review #1 Progress Review #2 University of Maryland! Page 9