[Pixhawk Setup]Motor specific config

I have been struggling to setup Pixhawk on my Mantis280 drone.

The problem is the drone never get stabilized and motor speed keeps diverge right after increasing the throttle.

Changing the PID gain didn't work.

ESC calibration didn't work.

RC calibration didn't work.

My final guess is about the motor and ESC combination I am using is as follows.

Motor: FR1806-2300KV from RCTimer

ESC: K18A ESC(KISS ESC18A) 2-4S also from RCTimer

Theses motors and escs are for racing equipment and has higher KV to normal setup.

I found slight increase of throttle causes too much output, so I decided to find ways to make pixhawk not to increase the output too much.

The way I found it adjusting the parameter in MOT section.

Launch Mission Planner and go to <CONFIG/TUNING> tab, then Open <Full Parameter Tree>

Find MOT section as below picture.

MOT_THST_MAX was 0.9 which means pixhawk will use 90% of the throttle range of the motor.

I reduced this number to 0.4

MOT_THST_EXPO governs the slope of response and higher number means more steep response to the motor.

Default was around 0.65 and also decreased to 0.5.

 

With above adjustment, the drone finally get stabilized!!

No twitching at all. Of course I may lose some power but I don't need that much of power for my drone purpose at this time.

 

This guide first uploaded on 2016/6/12 by Kyubot