Unable to setup tank style with SKID_STEER_X params

Hi there,

I’m just new to Rover platform :slight_smile:
I want to setup a basic 4 wheel vehicle so that I can drive it as a tank (RC1 and RC3 used as left/right instead of steer/throttle) using a Pixhawk, ESC, motors …
I had a look at the wiki and found that I had to set SKID_STEER_IN and SKID_STEER_OUT to 1. That’s what I did with mission planner.

Before pluging the pixhawk to the rest of the platform I wanted to ensure that PWM were correct on both RC1 and RC3 outputs.
So I plugged a joystick on the PC and assigned RIGHT stick to Throttle and LEFT stick to Roll and had a look at RC1 and RC3 outputs on the scope.

The behaviour is quite strange to me !! :open_mouth:
Behaviour I expected:

  • when moving left stick, RC1 ranges from pwm min to pwm max / RC3 is fix and set to trim
  • when moving right stick, RC3 ranges from pwm min to pwm max / RC1 is fix and set to trim
    Behaviour I have :
  • when moving left stick, RC1 ranges from pwm min to pwm max / RC3 changes between 2 lower values
  • when moving right stick, I have strictly the same thing that with left stick for RC1 and RC3!

I was wondering if I had to change some STEER_X values as steering has no real meaning in tank style …
Thanks for your help :slight_smile:

For a start only set SKID_STEER_OUT to 1.
What are you using for a receiver for your Pixhawk?
If using a Spektrum satellite receiver, you will have to modify the RCMAP_X parameters.
The skid steering output of the Pixhawk is usually on servo outputs 1 and 2.

I only set SKID_STEER_OUT to 1 but it doesn’t change the behavior.
For the moment I’m not using any radio command, I use a gamepad plugged to the PC with LEFT stick being the roll (assigned to servo1 via RCMAP) and RIGHT stick being the throttle (assigned to servo3 via RCMAP)




My friend and I have been using an X-Box gamepad with the Rover SITL and we have found that there are joystick issues when using Mission Planner so you are on your own.
I do not know if there will be any further development of the joystick function.

Whaou !! In fact all works fine :stuck_out_tongue:
I just understood how tank style works!!
I thought that in tank style left stick was driving left side motors and right stick was driving right side motors.
In fact right stick is still the throttle and left stick still the steering but the steering is done by having left/right motors turn in reverse directions.
Hope this topic could help those who just misunderstood as I did
Anyway, thanks TCIII for your help.