VITL Preliminary Design Review (PDR)

1. VITLPreliminary Design Review (PDR) Monday, November 10, 2014 Team Members: Ryan Hickman, Chris Homolac, Jen Krupp, Kyle Ligon, Heather Love, Alex Paulson, Kathryn Rash, Veronica Vertucci

2. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 2

3. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 3

4. Objectives & Goals Overview • Design and build a prototype for the locomotion system of a vehicle exploring Europa • Capable of traversing 1 km of icy terrain in 7 days • Capable of traversing obstacles characteristic of Europa • Maximize traversable incline • Maximize range • Minimize power draw and mass Vehicle for Icy Terrain Locomotion 4

5. Why Europa? One of the best candidates for life beyond earth Under Europa’s surface (~100m) is the most likely location for liquid water outside of Earth Technological Challenges Europa’s surface temperature is about 100K Power Radiation Traction 1/6 Earth gravity Objectives Overview Vehicle for Icy Terrain Locomotion 5

6. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 6

7. System Design Alternatives Wheeled Spider UAV Snake Roller Tracked Vehicle for Icy Terrain Locomotion 7

8. System Design Alternatives • Performance Variables • Experience • Power • Thermal • Traction • Speed • Stability • Complexity • Agility • Mass • Structure • Payload • Initial Calculations • Trade Study Weighting • Top Level Feasibility • Wheeled Architecture • 3, 4 and 6 Wheeled designs • Additional Trades • 6 Wheeled Design Vehicle for Icy Terrain Locomotion 8

9. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 9

10. System Design To Specifications Vehicle for Icy Terrain Locomotion 10

11. Design To Specifications • Traction and Maneuverability • Six wheels to grip icy terrain • Sufficient traction for accurate navigation • Autonomy • Sensors to detect hazardous terrain • Navigate unpredictable terrain • Survivability • Substantially built • Insulated to survive at cryogenic temperatures • Last seven days • Travel one kilometer • Payload attachment Vehicle for Icy Terrain Locomotion 11

12. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 12

13. Drive System Vehicle for Icy Terrain Locomotion 13

14. Drive: Design To Specifications • Geometry • Maximum Size of vehicle: 1 m3 • Terrain Crossing • Ice at 100 K • Ruts & Ridges: 1 m x 8 cm x 3 cm (L x W x H) • Inclination: 20° • Capabilities • Zero turning radius • Range: 1 km in 7 Earth days Vehicle for Icy Terrain Locomotion 14

15. Drive: Design Components Vehicle for Icy Terrain Locomotion 15

16. Drive: Drivetrain Alternatives Vehicle for Icy Terrain Locomotion 16

17. Design 3 Design 4 Design 1 Design 2 Drive: Wheel Alternatives • Location & Number Vehicle for Icy Terrain Locomotion 17

18. W D D Motor FN Fτ h Wheel Design Alternatives • Size Vehicle for Icy Terrain Locomotion 18

19. Drive: Motor Alternatives • Type NASA Report “Selection of Electric Motors for Aerospace Applications” Vehicle for Icy Terrain Locomotion 19

20. Drive: Suspension Alternatives • Type Vehicle for Icy Terrain Locomotion 20

21. Design A Design B Design C Suspension Design Alternatives • Turning Vehicle for Icy Terrain Locomotion 21

22. Sensors • Design-to-Specifications • Slope • Vehicle shall not exceed a slope of 20° • Obstacles • Vehicle shall detect obstacles that are larger than 1” as defined by customer • Cliff • Vehicle must be able to detect if a cliff, wall, or slope larger 20° is in its current path • Distance • Vehicle shall travel 100 m and be accurate to that distance within one vehicle body length Vehicle for Icy Terrain Locomotion 22

23. Sensors Vehicle for Icy Terrain Locomotion 23

24. C&DH/Comm Design Alternatives Vehicle for Icy Terrain Locomotion 24

25. Criteria Easily programmable Fair price Must be able to afford back up CPUs Supports enough ADC for all analog inputs If not, ability to add external ADCs or have two controllers working together C&DH: CPU Alternatives Vehicle for Icy Terrain Locomotion 25

26. Structures • Overview • Primary requirements • Volume less than 1 m3 • Survival at 100 K • Payload Considerations (<10 kg) • Flowdown requirements • Structural stability • Structure/drivetrain interactions • Support for subsystems (structural and wiring) • Maximum load sustained Vehicle for Icy Terrain Locomotion 26

27. Structures • Fundamental Design Alternatives • Primary structure layout • Box • Circular • Subsystem boxes • Shell • Wire frame • Drivetrain interface • Integration into design • Modular • Wiring support • Common bus • Distributed network Vehicle for Icy Terrain Locomotion 27

28. Structures • Primary Structure Layout Alternatives CircularBox -Minimize stress points -Conventional Design -Complex drivetrain interaction, stability -Straightforward drivetrain -Good for agility, common data/power -Strength may be an issue Vehicle for Icy Terrain Locomotion 28

29. Structural Feasibility Vehicle for Icy Terrain Locomotion 29

30. Power • Design To Specifications • Wattage/Voltage • Provide enough wattage and voltage to run all components needed for testing • Capacity • Provide a long enough run-time to verify the requirements for the tests Vehicle for Icy Terrain Locomotion 30

31. Power • Not a requirement for prototype but is still considered • Needed for testing purposes • Actual Rover • RTG’s - but these may cause contamination • Future technological advancements • Prototype • Batteries: Lithium Ion • Wide range of operating temperatures • High capacity • Rechargeable Vehicle for Icy Terrain Locomotion 31

32. Thermal • Design To Specifications • Thermal Vac • Provide the system with enough heat where needed to function properly at 100K • Other tests • Keep the ambient temperature of each of the components within operating temperatures Vehicle for Icy Terrain Locomotion 32

33. Thermal • Need to keep all internal components -20°C or above for prototype • Due to operating temperatures of most components • Actual Rover • Need heaters on all servos • Due to the specifications of the material used • Can use RHU’s • Aerogel Insulation • Prototype • Fiberglass insulation • Aerogel for thermal vacuum testing Vehicle for Icy Terrain Locomotion 33

34. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 34

35. Testing: Verification of Requirements Vehicle for Icy Terrain Locomotion 35

36. Testing: Needs Vehicle for Icy Terrain Locomotion 36

37. Testing: Terrain Course Vehicle for Icy Terrain Locomotion 37

38. Testing: Out of Prototype Scope • Design • Power Source • Testing • Europa Environment • Radiation • Pressure • Total vehicle at 100 K Vehicle for Icy Terrain Locomotion 38

39. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 39

40. Top Risks Assessment (1) Motor/Electronics Failure at 100K Use cryogenic motors/electronics Add heaters (2) Localized Stress Concentrations Design with large stress margins (3) Schedule Delays Overestimate time by at least 2x (4) Cost Overruns Apply for UROP/EEF Maximize existing facilities and resources (5) Availability of Testing Facilities Backup thermal tests at lower temp. Consequence Probability Vehicle for Icy Terrain Locomotion 40

41. Risk Assessment: Prototyping • Component boxes to represent subsystem loads and distributions • Motor testing in thermal vacuum (if available) • Possible materials testing in thermal vacuum (if available) Vehicle for Icy Terrain Locomotion 41

42. Overview • Project Objectives Overview • System Design Alternatives • System Design-To Specifications • Subsystem Design Alternatives & Feasibility • Drive System • Sensors & Software • Command & Data Handling (C&DH) • Structure • Power • Thermal • Testing Analysis • Risk Assessment • Project Management Plan Vehicle for Icy Terrain Locomotion 42

43. Organizational Responsibilities Vehicle for Icy Terrain Locomotion 43

44. Work Breakdown Structure (WBS) Vehicle for Icy Terrain Locomotion 44

45. PDR-CDR Schedule Vehicle for Icy Terrain Locomotion 45

46. Spring Semester Schedule Vehicle for Icy Terrain Locomotion 46

47. Cost Estimates • Will require additional funding from EEF/UROP grants Vehicle for Icy Terrain Locomotion 47

48. Limited Budget • Still possible without EEF/UROP funding • Requires substantial decrease in Testing and Structures and minor cuts in the remaining subsystems Vehicle for Icy Terrain Locomotion 48

49. Specialized Facilities and Resources • Ball Thermal Vacuum • University of Colorado Ice Rink • Lake Vehicle for Icy Terrain Locomotion 49

50. Acronym List • ADC: Analog to Digital Converter • C&DH: Command and Data Handling • COTS: Commercial Off The Shelf • CPU: Central Processing Unit • RF: Radio Frequency • RHU: Radioisotope Heater Unit • RTG: Radioisotope Thermoelectric Generator • RX: Receiver • TX: Transmitter • WBS: Work Breakdown Structure Vehicle for Icy Terrain Locomotion 50