1. Universal Chassis for Modular Ground Vehicles University of Michigan Mars Rover Team Presented by Eric Nytko August 6, 2005 The 2 nd Mars Expedition Planning Workshop

2. Universal Chassis for Modular Ground Vehicles Overview University of Michigan Mars Rover Team Concept of the Universal Modular Chassis Vehicle Classification Core Technologies Examples of Configurations and Mission Scenarios Conclusions

3. Universal Chassis for Modular Ground Vehicles Michigan Mars Rover Team Student research group founded in 2000 Designs, fabricates, and tests manned ground vehicles for planetary exploration Inspires and educates students about space exploration 2 nd place in RASC-AL Forum’05 with Universal Chassis Concept

4. Universal Chassis for Modular Ground Vehicles Mobility Challenges Mars Exploration Rovers Speed: 0.18 km/hr Payload: 45 kg Future Capabilities Speed: 20 km/hr Payload: 3000 kg Support long-range, long-term human operations

5. Universal Chassis for Modular Ground Vehicles Concept of the Universal Modular Chassis Developmental Advantages More thorough design and testing Reutilization of research resources Standardization of procedures and equipment Operational Advantages Less total launch mass Increased redundancy and mission flexibility Increased crew experience Disadvantages Unused subsidiary capabilities Design complexity

6. Universal Chassis for Modular Ground Vehicles Vehicle Types and Functional Requirements Robotic Exploration Rover Pre-EVA scouting EVA Assistant All Terrain Vehicle Single-person mobility Unpressurized Rover Short-range crew transport Utility Truck Equipment transport Pressurized Rover Long-range crew transport Construction Rover Nuclear reactor transport Road grading Creating banks of soil

7. Universal Chassis for Modular Ground Vehicles Classifications

8. Core Technologies Interfaces and modularity Computing Drive control Hub motors Mobility Fuel cells and fuel storage

9. Universal Chassis for Modular Ground Vehicles Interfaces and Modularity Chassis must provide Power Communication with modules Structural support Thermal control Allows for body modularity and chassis universality

10. Universal Chassis for Modular Ground Vehicles Computing Software and hardware modularity Modular development infrastructure Autonomous or semi- autonomous operation

11. Universal Chassis for Modular Ground Vehicles Drive Control Eliminates hydraulic and mechanical linkages Reduces launch mass Robust and redundant control Incorporates both autonomy and human control Commercial automotive solution in rad-hard applicable

12. Universal Chassis for Modular Ground Vehicles Hub Motors Power individual wheels Greater motion control Interface with electronic drive control Higher efficiency and redundancy

13. Universal Chassis for Modular Ground Vehicles Mobility CompanyTRLProducts GM4Hummer (Front: Torsion bar & gas shocks, Rear: Multi- Link w/ var. rate coils & gas shocks, 4 17" by 8.5" wheels) Boeing9Lunar Rover (double horizontal wishbone, 4 wheels) Peugeot4Quark ATV (triangular wishbone, 4 17" wheels) JPL9MER/MSL (Rocker-Bogie, 6 wheels) John Deere and iRobot 4R-Gator (4 wheels) Vehicle mobility is dependent on suspension and wheels Suspension Reduces effects of rough terrain Supports vehicle weight Maintains wheel contact for sufficient traction Controls direction of travel Wheels Critical to overcoming obstacles Reduce effects of inconsistent terrain

14. Universal Chassis for Modular Ground Vehicles Fuel Cells and Fuel Storage Power system affects design, capabilities, and mission architecture Fuel cells More efficient than other power systems Adaptable Scalable Easily configured to fit universal chassis platforms Fuel storage Liquid methane and oxygen Pressurized tanks CompanyTRLProducts GM6PEM Fuel Cells (129 kW/100 kg) Honda4FCX Fuel Cells (80kW)

15. Universal Chassis for Modular Ground Vehicles Design Overview Universal chassis comparison Small chassis design Medium chassis design Large chassis design Modularity example

16. Universal Chassis for Modular Ground Vehicles Universal Chassis Comparison 1m 0.6m 0.3m 1.9m2.5m 4.5m 1.9m 3.0m 4.8m 1.2m 1.7m 2.5m 120 kW 2000 kW-hr 16kW 24 kW-hr 8 kW 6 kW-hr 2000 kg 400 kg 250 kg 3000 kg 300 kg 150 kg Carrying capacity

17. Universal Chassis for Modular Ground Vehicles Small Chassis Design Hub Motors Reformer Methane Storage Oxygen Storage Computing Mobility Fuel Cell Interfaces

18. Universal Chassis for Modular Ground Vehicles Medium Chassis Design Hub Motors Reformer Methane Storage Oxygen Storage Fuel Cell Mobility Computing Interfaces

19. Universal Chassis for Modular Ground Vehicles Large Chassis Design Hub Motors Reformer Methane Storage Oxygen Storage Fuel Cell Mobility Computing Interfaces

20. Universal Chassis for Modular Ground Vehicles Modularity Example: Small Chassis The same small chassis can support both ATV and EVA assistant functions and be reconfigured in the field

21. Universal Chassis for Modular Ground Vehicles Mission Scenario Example for Small Chassis Mission with multiple dispersed sites (scouting): Use Small Chassis with ATV and Robotic Exploration Rover payloads to cover more ground Mission with small number of interesting sites (in-depth site exploration): Use Small Chassis with EVA Assistant payload to investigate the site during EVA

22. Universal Chassis for Modular Ground Vehicles Modularity Example: Large Chassis The same large chassis can support both the Construction Vehicle and Pressurized Rover

23. Universal Chassis for Modular Ground Vehicles Mission Scenario Example for Large Chassis Land vehicle with Nuclear Reactor Deployment payload Deploy nuclear reactor before crew arrives Use Construction payload for base construction Use Pressurized payload for long range exploration

24. Universal Chassis for Modular Ground Vehicles Conclusions Universal chassis concept will support a variety of missions and mission scenarios for all aspects of base operation Cost sharing with other technology sources will reduce development expenses Development plan must leverage current and future automotive technology

25. Universal Chassis for Modular Ground Vehicles Questions?