Motor shutdown in air

jinchengde · December 21, 2021, 4:58am

@bnsgeyer
hi bill, thanks for you reply
yes, the collective pitch is setup for 3D
H_COL_MAX 10 degree
H_COL_MID 0 degree
H_COL_MIN -10 degree

In messages, we see that “LAND_COMPLETE_MAYBE”, so check the land_detector code

github.com

ArduPilot/ardupilot/blob/db0f06fb581fe3ae15d666a0c338ba85a3842c27/ArduCopter/land_detector.cpp#L99-L102

    
      
          if (motor_at_lower_limit && accel_stationary && descent_rate_low && rangefinder_check && WoW_check) {
              // landed criteria met - increment the counter and check if we've triggered
              if( land_detector_count < ((float)LAND_DETECTOR_TRIGGER_SEC)*scheduler.get_loop_rate_hz()) {
                  land_detector_count++;

the detect condition include
motor_at_lower_limit
accel_stationary
descent_rate_low
rangefinder_check
WoW_check

so , let’s check the motor_at_lower_limit

github.com

ArduPilot/ardupilot/blob/db0f06fb581fe3ae15d666a0c338ba85a3842c27/ArduCopter/land_detector.cpp#L68-L69

    
      
          bool motor_at_lower_limit = ((flightmode->has_manual_throttle() && (motors->get_below_land_min_coll() || heli_flags.coll_stk_low) &&
                                      fabsf(ahrs.get_roll()) < M_PI/2.0f) || (motors->limit.throttle_lower && pos_control->get_vel_desired_cms().z < 0.0f));

RTL flightmode have auto throttle but not manual, so it looks like no relation with collective pitch