ADVANCING TECHNOLOGY AND EDUCATION FOR A HUMAN BASE ON THE MOON AND FOOTPRINTS ON MARS Presentation to the Engineering Dean’s Conference Nancy J. Currie, Ph. D. Deputy Director, JSC Engineering NASA, Johnson Space Center
ADVANCING TECHNOLOGY & EDUCATION FOR A HUMAN BASE ON THE MOON AND FOOTPRINTS ON MARS AGENDA Challenges Space Shuttle International Space Station Constellation Examples of Current Collaborations with Academia Dexterous Robotics Autonomous Rendezvous and Docking Preparation of NASA’s Future Engineering Workforce Working in multi-disciplinary teams Systems Engineering Process and procedures
Vision for Space Exploration Space Shuttle Use Space Shuttle to transport elements and complete assembly of the International Space Station (ISS) Retire the Space Shuttle when ISS assembly is complete (2010) International Space Station Complete ISS assembly including the U. S. components that support U. S. and foreign partners space exploration goals Focus ISS research on supporting space exploration goals Space Exploration Beyond Low Earth Orbit Undertake lunar exploration activities to enable sustained human and robotic exploration of Mars and more distant destinations in the solar system Initiate a series of robotic missions to the Moon to prepare for and support future human exploration activities Conduct the first extended human expedition to the lunar surface as early as possible but no later than the year 2020 Use lunar exploration activities to further science, and to develop and test new approaches, technologies, and systems, including use of lunar and other space resources, to support sustained human space exploration to Mars and other destinations
Engineering Challenges Associated with the Space Shuttle Safe and successful completion of all missions through end of program life Risk due to debris can never be completely eliminated Impacts from debris is an inherent risk based on Space Shuttle design Minimal tolerance for debris impacts Methods to repair the Shuttle’s thermal protection system (TPS) on orbit are desired TPS repair consists of three problems: Materials capable of withstanding entry temperatures and concepts for attachment of repair systems Operability problems performing repairs in the space environment (microgravity, thermal) Engineering verification that repairs can withstand thermal effects during entry Repair Capabilities Tile - Emittance wash; Shuttle Tile Ablator-54; Tile overlay Reinforce Carbon-Carbon - Crack repairs, Plugs, Overlay* * R&D development project
Space Shuttle Foam Impact Analysis and Testing Foam projectile representative debris Foam projectile released during debris Foam projectile representative debris representative STS-107: 19” x 11. 5”during STS-107: released x 5. 5” released during STS-107: 1. 67 lbs 19” x 11. 5” x 5. 5” density of 2. 4 lbs/ft 3 1. 67 lbs density of 2. 4 lbs/ft 3 Velocity at liberation ~2, 300 fps Velocity atat impact ~1, 500 fps Velocity liberation ~2, 300 fps Velocityat impact ~1, 500 fps liberation ~2, 300 Velocity at to low ballistic coefficient of ∆V due Velocity at impact ~1, 500 fps ∆V due to low foam low-density ballistic coefficient of ∆V due to low ballistic coefficient of low-density foam
Space Shuttle Challenge - Tile Repair Emittance Wash RTV base material with silicon carbide filler Apply material on damaged tiles to increase heat rejection through radiation by increasing surface emittance (ε) to >0. 76 Shuttle Tile Ablator 54 (STA-54) Mixture of Room-Temperature-Vulcanizing (RTV) rubber, glass microballoons, silicone oil, a fumed silica, and a catalyst RTV material serves as the base material for the reaction is mixed with a catalyst Silicone condensation reaction creates a silicone rubber that is pyrolized during entry heating to a ceramic state Materials loaded into two separate tubes housed in a caulk-gun-like applicator which mixes the two parts as EVA astronauts dispense it into the damaged area
Space Shuttle Challenge - Tile Repair Tile Overlay Concept Purpose: Elevate thermal capability of the damaged thermal protection system tiles by covering damaged area with a thin, flexible plate Tile Overlay repair hardware consists of four parts: Coated C/Si. C overlay plate (0. 040” x 15” x 25”) shielding the damage area from plasma flow Compliant alumina (Saffil) as gasket to eliminate plasma flow between cover plate and tile OML and reduce radiant heating Saffil blankets/bags inside the cavity to minimize radiant heating Augers/washers to secure cover plate to Vehicle
Engineering Challenges for Crew Exploration Vehicle Skip Entry Landing site “Skip” maneuver can be used to adjust landing site to guarantee anytime return from any lunar latitude to a single identified CONUS landing location Capability to perform a skip entry estimated at Technology Readiness Level 3 Guidance, navigation, control, TPS, aerodynamics, environment, mass properties STS-107 investigation concluded a number of high atmosphere phenomena (winds, density shears) challenge entry guidance algorithms SM Disposal Footprint Antipode 7, 350 nm Descending Approach to KSC Nominal Ballistic Abort Landing Antipode Entry Interface motion during lunar month TEI Moon at -28. 6 degs Minimum declination 7, 350 nm Ascending Approach to KSC Constant Radius Access Circle (CRAC) 7, 350 nm
Engineering Challenges for Automated Rendezvous and Docking is not a system; but a complex phase of flight that is tightly integrated with many vehicle subsystems Automated is typically used to mean “scripted; ” Autonomous is used for applications that operate without human intervention Level of automation or autonomy varies greatly based on application
Engineering Challenges: Docking/Capture Systems Docking/capture envelope influences: Relative navigation sensor accuracy requirements Trajectory and approach profile Vehicle thruster size and placement Extremely specialized field with few experts (even internationally) Low Impact Docking System (LIDS) for the Crew Exploration Vehicle Two docking systems are under consideration for CEV docking to the International Space Station - Androgynous Peripheral Attachment System (APAS) and the Low Impact Docking System (LIDS)
Engineering Challenges: Relative Navigation Sensors Relative navigation sensors are used to provide the crew, vehicle, and ground elements with relative navigation data between two spacecraft Provide the backbone for the capability to have automated operations Provide “situational awareness” for piloted operations Relative navigation sensors may be laser-based, radio frequency (RF)based, or based on a video system Laser-based and video based typically have reflectors or visual targets on the target spacecraft Specific Challenges: Technology is too immature for human spaceflight (low technology readiness levels) Sensor redundancy and overlap for reliability Sensors that provide good accuracy at short range do not necessarily provide long range capability Sensor placement and visibility Target infrastructure to support sensors (reflectors, transponders, visual targets, etc. )
Academic Collaborations - Robotics Focus Areas Surface Mobility Crew mobility on Lunar Surface Movement of cargo on Lunar Surface Handling Deployment of instruments Assembly and Repair Command & Control Earth-Moon Time Delays Human-Robot EVA Teams Current University Collaborations Dexterous Manipulation (UMass) Motion Control (Clemson) Learning Algorithms (Vanderbilt) Autonomous Manipulation (MIT) Lunar Polar Exploration (CMU) Recent Academic Partners University of Southern California; University of Texas-Austin; Texas A&M, University of Houston, University of Washington, Rice University, University of Oklahoma
Academic Collaborations - Autonomous Rendezvous and Docking Ability for two spacecraft to autonomously rendezvous and dock (AR&D) is critical for the success of future human spaceflight missions Two universities (University of Texas & Texas A&M University) will independently build two spacecraft with communications and mechanically interfaces for successful rendezvous and dock Project initiated by JSC Engineering, Aeroscience and Flight Mechanics Division in the fall of 2005 Anticipated to be an 8 -year program - satellite launches ~ every 2 years JSC Engineers serve as mentors with significant support and assistance from the faculty and staff of both universities Objectives of the project include: Demonstrate precision relative navigation Demonstrate precision real-time navigation Provide orbit determination Mission duration - minimum of 24 hours Data collection and downlink over 75% of the mission duration
JSC Engineering Workforce Demographics
Preparation of JSC’s Engineering Future Workforce Experience working in multi-disciplinary teams Design of most spacecraft systems requires a “Mechatronics” approach Electrical, mechanical, aero, software “Optimal” design rarely possible, compromise almost always required to meet myriad of competing requirements Training in Systems Engineering Skills in systems engineering and integration are extremely important for design and development of large-scale aerospace projects Government will have a more substantial role in spacecraft development Use of collaborative engineering tools NASA and most large aerospace companies are geographically dispersed Process and procedures associated with engineering projects Student projects can use real-world examples and the phasing of project deadlines can emulate typical project milestones Requirements, design, and safety reviews Familiarizes students with typical project management constraints – technical, schedule, cost
Preparation of NASA’s Future Engineering Workforce Training in Systems Engineering Systems integration and control Systems acquisition and life cycle management Requirements development/analysis/management System verification/validation Integrated planning and scheduling Cost estimating Risk Management Pilot Program in Systems Engineering 39 engineers at JSC will participate Courses taught by California Institute of Technology (professors will travel to JSC) and University of Southern California (distance learning)
ADVANCING TECHNOLOGY AND EDUCATION FOR A HUMAN BASE ON THE MOON AND FOOTPRINTS ON MARS QUESTIONS? JSC Engineering Contact Information Director: Mr. Stephen J. Altemus; 281 -483 -1396; stephen. j. altemus@nasa. gov Deputy Director: Dr. Nancy J. Currie; 281 -483 -8018; n. currie@nasa. gov Mailing Address: NASA – Johnson Space Center Mailcode EA 2101 NASA Parkway Houston, TX 77058
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