FlightModeManager: fix integral reset on ground

This information could also be used for yaw and integral
resets of the lower level controllers.

msg/vehicle_constraints.msg

@@ -11,4 +11,5 @@ float32 tilt # in radians [0, PI]
 float32 min_distance_to_ground # in meters
 float32 max_distance_to_ground # in meters
 bool want_takeoff # tell the controller to initiate takeoff when idling (ignored during flight)
+bool reset_integral # tells controller to reset integrators e.g. since we know the vehicle is not in air
 float32 minimum_thrust # tell controller what the minimum collective output thrust should be

src/modules/flight_mode_manager/FlightModeManager.cpp

@@ -454,7 +454,7 @@ void FlightModeManager::generateTrajectorySetpoint(const float dt,
 		// set yaw-sp to current yaw
 		setpoint.yawspeed = 0.f;
 		// prevent any integrator windup
-		// _control.resetIntegral(); TODO
+		constraints.reset_integral = true;
 	}
 
 	_trajectory_setpoint_pub.publish(setpoint);

src/modules/mc_pos_control/MulticopterPositionControl.cpp

@@ -254,6 +254,10 @@ void MulticopterPositionControl::Run()
 			_control.setConstraints(constraints);
 			_control.setThrustLimits(constraints.minimum_thrust, _param_mpc_thr_max.get());
 
+			if (constraints.reset_integral) {
+				_control.resetIntegral();
+			}
+
 			// Run position control
 			if (_control.update(dt)) {
 				_failsafe_land_hysteresis.set_state_and_update(false, time_stamp_now);