Behavior on motor failure

What is px4 behavior on motor failure in multicopter?
As I understand if you have 6 or 8 rotors you should not fall.
Are there any special logic in px4 which can detect such case and stop opposite motor to compensate yaw?
Are there SITL config to simulate motor failure?

@LorenzMeier Could you explain this?


There is no special behavior because there is no detection or feedback from the motors/ESCs.

Hexs or Octos are able to fly with a motor failure if and only if the integral gains are set high enough. Without integral gains, it will be difficult to counteract the asymmetry caused by a motor out.

I usually recommend to test the behaviour with a motor out using some sort of instrumentation, so that one motor can be disabled mid-flight. Alternatively, you could also disconnect one, and try to take-off.

The logic is to compensate an asymmetry using the integral in the controller. There is no detection logic because that’s generally a hard thing to get right because you don’t want any false positives, ever.
A cleverer way would be smarter ESCs with feedback, of course.

Good idea! Not that I’m aware off, although it would be fairly easy to add.

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