Merge remote-tracking branch 'upstream/master' into ros_messagelayer_merge_attctlposctl

src/modules/mc_pos_control/mc_pos_control_main.cpp

@@ -35,6 +35,12 @@
  * @file mc_pos_control_main.cpp
  * Multicopter position controller.
  *
+ * Original publication for the desired attitude generation:
+ * Daniel Mellinger and Vijay Kumar. Minimum Snap Trajectory Generation and Control for Quadrotors.
+ * Int. Conf. on Robotics and Automation, Shanghai, China, May 2011
+ *
+ * Also inspired by https://pixhawk.org/firmware/apps/fw_pos_control_l1
+ *
  * The controller has two loops: P loop for position error and PID loop for velocity error.
  * Output of velocity controller is thrust vector that splitted to thrust direction
  * (i.e. rotation matrix for multicopter orientation) and thrust module (i.e. multicopter thrust itself).
@@ -727,11 +733,18 @@ MulticopterPositionControl::control_auto(float dt)
 		reset_alt_sp();
 	}
 
+	//Poll position setpoint
 	bool updated;
 	orb_check(_pos_sp_triplet_sub, &updated);
-
 	if (updated) {
 		orb_copy(ORB_ID(position_setpoint_triplet), _pos_sp_triplet_sub, &_pos_sp_triplet);
+
+		//Make sure that the position setpoint is valid
+		if (!isfinite(_pos_sp_triplet.current.lat) || 
+			!isfinite(_pos_sp_triplet.current.lon) || 
+			!isfinite(_pos_sp_triplet.current.alt)) {
+			_pos_sp_triplet.current.valid = false;
+		}
 	}
 
 	if (_pos_sp_triplet.current.valid) {