On his picture above is RC trim is set to 1543.
isn’t it for a normal mode PWM throttle Ardupilot takes RC trim as zero throttle an so is not going below?
He can try to set RC trim to around 1000 than the the ESC might work but Ardupilot will missinterpret the zero throttle value
That’s servo trim. But it’s a common mistake to miscalibrate the throttle RC channel, which results in this behavior.
If you want reverse, the throttle channel needs to have a trim point in the middle. Zero throttle should be full reverse. Mid throttle should be stopped. Full throttle should be full forward.
Solution : set RC3_TRIM to 1500
So now when throttle is fully down (ch3 in at min value) at 988us then Pixhawk send 988us to the cytron motor driver (full speed reverse motor spin direction) and when throttle is fully up (ch3 in at max value) at 2011 us the PIxhawk sends 2011us to the cytron motor driver (full speed forward motor spin direction).
So it works now as intended. However what I do not understand is why during the radio calibration, mission planner did not set the middle point correctly. It has set the max (2011us) and minimun (988us) coorectly but it had also set wrongly the mid point to the minimum value (988us) instead of the middle point value (1500us).
Is this a bug in the radio calibration routine of mission planner?
In the meantime I would suggest adding an important note in the wiki for ardurover motor setup ( Motor and Servo Configuration — Rover documentation) to set and check manually in the full parameters list the RC3_TRIM value and set it to the mid point of the throttle curve.
(especially that this issue of not being able to reverse direction in ardurover is a recurring question asked on many forums for many years now. So this point is obviously not clear for most people…)
A window will appear with the prompt, “Ensure all your sticks are centered and throttle is down and click ok to continue”. Move the throttle to the center and press “OK”.
