I’m building custom mission handler on companion computer. Missions looks like this:
Arm motors on POS_HOLD mode
Takeoff with MAV_CMD_NAV_TAKEOFF
Switch to GUIDED_NOGPS mode (indoors flight with OF sensor)
Fly wherever with SET_ATTITUDE_TARGET command
Problem is that step 3 (command 176) fails with result code 3 (MAV_RESULT_UNSUPPORTED).
Little confusing since as far as i know, GUIDED_NOGPS should be supported with AC 3.5.3 vesion.
If you got no gps, you need to set the home position before takeoff ! It is needed to initialise the EKF and you need to use EKF3 I think. Check on wiki how it should be done