Octanis Rover Drive Tests

Todo:

  • Check GPS_RAW_INT message for correctness.
  • Check correct survey in.
  • Send waypoints.
  • Check arm/disarm (via ethernet). Recording script on olimex must be running (and acknowledge the arm command).
  • Check navigation (are waypoints reached) - use ethernet, not lora (disabled).

Observations:

  • Slipping >20° with peak 4.9A at 3.3V
  • Max speed 6.25cm/s
  • Radius at 80/100%: 4.25m
  • 20° feasible, above 23° total slip on wet snow
  • FBS Battery open circuit at the end of test (solar was connected): 3.99V 0C
  • Test duration: 11:30 - 15:30
  • Base station is fully charged, weather was mostly cloudy with intermittent sun
  • shutdown script on rover runs in wrong ENV
  • All struts locked results in worse performance than if one side is unlocked from the body
  • Bad packing of rover
  • Objective: Recharge while driving. Mitigate resets. Tune PID.
  • Continuous driving test at EPFL campus starting 20:22 and ending 23:20.
  • Free drive until reset:
    • 21:00 - 21:15
    • 21:15 - 21:24
    • 21:24 - 21:28
    • 21:28 - 21:45
    • 21:45 - 21:47
    • 21:48 - 21:51
    • 21:51 - 21:52
    • 21:52 - 22:15
    • 22:15 - 22:24
    • 22:24 - 22:28
    • 22:28 - 22:30
    • 22:30 - 22:57
    • 22:57 - 23:08
  • Wheel Hub detached from M4 at 23:05 due to vibrational loosening of the set screw. This will be resolved with a bit of Loctite.
  • ~2m turning radius was measured
  • 218m/h speed was measured
  • battery voltage (at room temperature, no load):
    • beginning: 4.08 V
    • end: 3.66 V
  • battery voltage (at outdoor temperature (10°C), under driving load)
    • beginning: 3.67 V (ADC 8-bit value: 156)
    • end: 2.90 V (ADC 8-bit value: 46) –> note that this voltage is below the pre-programmed 20% battery charge level (threshold = 2.95 V (ADC_val = 52)), at which the 11V motor supply voltage is turned off)