1. Michael Wagner, Stuart Heys, Dimi Apostolopoulos, Chris Williams
Rover Mobility
Michael Wagner, Stuart Heys,
Dimi Apostolopoulos, Chris Williams

2. Traverse Speed
In 2004, science operations saw Zoë driving at 1.8 km/hr
Further testing in Pittsburgh showed Zoë can achieve 3.2 km/hr
Science maneuvers or obstacle avoidance slows down the average speed to a new locale
Maximum Speed [km/hr]
Turning Radius [m]
Zoë Speed Limits
Navigator Arc Set
Close
Maneuvers

3. Mobility Problems: Slopes
Maximum slope on fine sand is much lower than on rocky slopes
Once it slips, it starts digging its wheels into the soil
Humans better than autonomy system at handling slops
Humans back up or pick a path that is not too steep
Autonomy software much more likely to begin slipping

4. Tough Terrain
Steep
slopes
Channels
Sandy?

5. Tough Side Slope
Wheels
slip
Axles
rotate

6. Mobility Problems: Obstacles
Too many obstacles: rover cannot find a safe path
Zoë will back up and try again
This recovery maneuver does not always work!
Obstacles sticking out of the ground are manageable
Holes and ditches are much more difficult to see

7. Mobility Problems: Faults
Zoë gets stuck driving along one side of a fault, railroad or drainage
Go up and down drainages
Faults are not always wide enough to see in DEM but often deep
Man-made stuff is really bad

8. Trenches, Roads

9. Humanity
Ditches
Pits
Roads

10. More Tough Terrain

11. No Problem

12. Mitigating Risk Can you find dangerous terrain from orbit?
Some obstacles can’t be seen even on high resolution data
Should use SPI panoramas for guidance
The paths will be significantly safer with a rover expert helping to create the plan

13. How to Handle Failures?
How do we handle navigation failures autonomously?
Must have some kind of run-out plan
Be able to recover next sol with human oversight
FI mosaics may also fail due to driving problems: tough to build mosaic on rough surface
Basically, forget any chance of returning to an FI location

14. Targeted Moves
Unreachable
Unreachable
Unreachable