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Engineering Challenges at JSC - NASA

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Engineering Challenges at JSC - NASA Powered By Docstoc
					         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 the 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
 representative STS-107:
released during debris
  Foam projectile representative debris
  released x 5.5”
19” x 11.5”during STS-107:
 released during STS-107:
  19” x 11.5” x 5.5”
1.67 lbs
 19” x 11.5” x 5.5”
density of 2.4 lbs/ft3
  1.67 lbs
 1.67 lbs
  density of 2.4 lbs/ft3
 density of 2.4 lbs/ft3




  Velocity at liberation ~2,300 fps
  Velocity liberation ~2,300 fps
Velocity atat impact ~1,500 fps
 Velocityat impact ~1,500 fps fps
             liberation ~2,300
Velocity at to low ballistic coefficient of
     ∆V due
 Velocity at impact ~1,500 fps
   ∆V due to lowfoam
     low-density ballistic coefficient of
    ∆V due to low ballistic coefficient of
   low-density foam
    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/SiC 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
                                                             SM
                                                           Disposal
  adjust landing site to guarantee                         Footprint
                                                                       7,350 nm Descending
  anytime return from any lunar        Antipode
                                                              Nominal
                                                                       Approach to KSC                     TEI
  latitude to a single identified                             Ballistic
                                                              Abort
  CONUS landing location                                           Antipode motion
                                                              Landing
                                                                                             Moon at -28.6 degs
                                        Entry Interface           during lunar month         Minimum declination
 Capability to perform a skip
  entry estimated at Technology                                                7,350 nm Ascending
                                                                               Approach to KSC
  Readiness Level 3
     Guidance, navigation, control,     Constant Radius Access
                                         Circle (CRAC) 7,350 nm
      TPS, aerodynamics,
      environment, mass properties

 STS-107 investigation
  concluded a number of high
  atmosphere phenomena
  (winds, density shears)
  challenge entry guidance
  algorithms
         Engineering Challenges for Automated Rendezvous
                           and Docking


              Subsystems or Areas
              that are integrated for            GN&C                 THERMAL
                      AR&D

                  Flight System
                   Influenced           Mission Manager                POWER
                   by AR&D



 Automated Rendezvous                           FDIR                  C&DH
  and Docking is not a
  system; but a complex                 IVHM                            COMM.
  phase of flight that is
  tightly integrated with
  many vehicle subsystems                      SENSORS              VEHICLE
                                                                    CONFIG
 Automated is typically                  FLIGHT
  used to mean “scripted;”                                    PROPULSION
                                        PROCESSORS
  Autonomous is used for
  applications that operate                       DOCKING          EXTERNAL SYSTEM
  without human                                    SYSTEM        (Grnd, GPS, TDRSS, Etc.)

  intervention                             HUMAN             GROUND
                                         INTERFACE          PLANNING
 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
      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

                               Highest Degrees - Directorate                                                 Degree Fields - Directorate
                                                                             250
                                            PhD None                                                                                                      224
                                             58  44      Assoc
                                                 5%                          200
                                            7%             6                                                               171
                                                                                       166
                                                          1%
                                                                             150
                               Mast
                               263
                                                                             100
                               31%
                                                                                                                                                                    45
                                                          Bach               50                                           36                                                           29
                                                                                                            27                                      27
                                                                                                                 20                                                      19
                                                           476                                         10             6                    11            11                       11
                                                                                   1         1 2 1 2                             3 2 1 1        4               4             1             1 1 3 1 1 4
                                                          56%                 0




                                                                                         Chem

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                                                                                    Humanitie



                                                                                          Matl

                                                                                         Metal
                                                                                          Civil




                                                                                   Plant Phys
                                                                                     Physical



                                                                                            SE
                                                                                          Geo




                                                                                          Math

                                                                                         Mech

                                                                                         None
                                                                                      Environ




                                                                                       Phych


                                                                                       Physio
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                                                                                         Tech.
                                                                                         Other
                                                                                          Elec




                                                                                         Legal




                                                                                      Physics



                                                                                   Secre. Sci
                                                                                           Bio
                                                                                   BusAdmin
                                                                                            AI




                                                                                    Unknown
                                                                                    AstroPhy
                                                                                         Aero


                                                                                       Astron
                                                                                     Account


                                                                                          Arts
                    Directorate Distribution by Age
50

45                                                                                                                    Degree Field - Directorate
40                                                                                                                             Physics
                                                                                                                                 29                 Aero
35                                                                                                                               3%                 166
                                                                                                        All Other
30                                                                                                                                                  19%         BusAdmin
                                                                                                           196
                                                                                                                                                                   27
25                                                                                                        22%
                                                                                                                                                                   3%
20                                                                                                                                                              Comp
15                                                                                                                                                               36
                                                                                                                                                                 4%
10

5
                                                                                                                                                         Elec
0                                                                                                                 Mech                                   171
     20   25   30    35   40   45    50   55   60   65   70   75   80   85                                         224                   Math            20%
                                                                                                                  26%                     27
                                      Age
                                                                                                                                          3%
         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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posted:1/6/2013
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