Pixhawk autopilot problems with skid steer rover

Hello, I have been troubleshooting for several days with getting Guided mode to work for my rover.

-Pixhawk with Ublox gps
-Spektrum DX6i tx with satellite reciever
-Sabertooth 2x60 speed controller (dip switch positions 1:Down, 2:Up, 3:Up, 4:Down, 5:Up, 6: Up)
-Skid steering setup with wheelchair motors

I am using left stick for throttle and right stick for steering. It works great in manual mode but flipping to Guided mode makes the rover spin in circles with only one motor operating.

There is GPS fix and the compass and GPS headings are pointing in the correct direction.

From the Pixhawk, I am using outputs 1 and 3 going into the Sabertooth S1 and S2 respectively.

I know people have had similar issues, but I have not found a solution that works. Any suggestions would be greatly appreciated as I am presenting the rover as my final engineering project in 2 weeks.

Thank you!

Update: I reversed the motor outputs from the pixhawk and it doesn’t spin in circles but now it turns West and continues straight. Not toward the waypoints.


We got some patch on road : https://github.com/ArduPilot/ardupilot/pull/3756 , https://github.com/ArduPilot/ardupilot/pull/3828 . I can provide you the compiled filed to test if you want.
In rover 3.0, you need to arm motor or it will do the crazy things you see (there are other bugs in skid steering mode)

1 Like

I think I had the same problem with the turn to the West last week.
You could actually see that even though the mission was read properly, the orange heading to next WP on Mission Planner was westwards.

The problem was solved with a powercycle (I think) so I didn’t give much thought to it.