Change Skidsteering Motor ratio

[Simon6468]

Hello,
i have a skid steer boat setup with Ardurover. Ive just tried the Autopilot and have one problem. When the boat is approaching a waypoint its slowing down to zero Speed to turn on the spot. But it doesnt turn on the spot because the outer motor is turning too much / the inner Motor isnt enough reversing. Is there a parameter or setting to change that?
Heres a picture of the result.
Thanks in advance

[geofrancis ([𝙂𝙚𝙤])]

you will need to adjust MOT_THST_ASYM: Motor Thrust Asymmetry.

https://ardupilot.org/rover/docs/parameters.html#mot-thst-asym-motor-thrust-asymmetry

[Simon6468]

Thank you a lot worked for me

[xen0mk (Stefan Spirkovski)]

Hey Simon or @geofrancis I would appreciate your help if possible

I was reading the documentation, I have the same behavior. So for example if I turn left (stern facing me), the right motor spins faster then the left motor asking for reverse, and the turn radius is high because it’s propelling forward the hull.

I can see that you can edit the parameter MOT_THST_ASYM only in positive increments, but not negative. If for example I set it to 2, does that mean that the reverse trust will be twice as the forward one?

[geofrancis ([𝙂𝙚𝙤])]

@xen0mk

ause it’s propelling forward the hull.

I can see that you can edit the parameter MOT_THST_ASYM only in positive increments, but not negative. If for example I set it to 2, does that mean that the reverse trust will be twice as the forward one?

yes that will run the propeller going backwards twice as fast to compensate.

[xen0mk (Stefan Spirkovski)]

Thanks Geo fixed it!