FeasibilityChecker: Add new TakeoffLandAvailable option

ADd a new misison feasiblity checker option to check if a proper landing approach is defined when in air. There must be at least a mission landing or a VTOL approach defined in order for the mission to be accepted. Else, use the same logic as in MIS_TKO_LAND_REQ=4

src/modules/navigator/MissionFeasibility/FeasibilityChecker.cpp

@@ -125,6 +125,12 @@ void FeasibilityChecker::updateData()
 		_current_position_lat_lon = matrix::Vector2d(vehicle_global_position.lat, vehicle_global_position.lon);
 	}
 
+	if (_rtl_status_sub.updated()) {
+		rtl_status_s rtl_status = {};
+		_rtl_status_sub.copy(&rtl_status);
+		_has_vtol_approach = rtl_status.has_vtol_approach;
+	}
+
 	param_t handle = param_find("FW_LND_ANG");
 
 	if (handle != PARAM_INVALID) {
@@ -577,17 +583,22 @@ bool FeasibilityChecker::checkTakeoffLandAvailable()
 		break;
 
 	case 4:
-		result = _has_takeoff == _landing_valid;
+		result = hasMissionBothOrNeitherTakeoffAndLanding();
+
+		break;
 
-		if (!result && (_has_takeoff)) {
-			mavlink_log_critical(_mavlink_log_pub, "Mission rejected: Add Landing item or remove Takeoff.\t");
-			events::send(events::ID("navigator_mis_add_land_or_rm_to"), {events::Log::Error, events::LogInternal::Info},
-				     "Mission rejected: Add Landing item or remove Takeoff");
+	case 5:
+		if (!_is_landed && !_has_vtol_approach) {
+			result = _landing_valid;
 
-		} else if (!result && (_landing_valid)) {
-			mavlink_log_critical(_mavlink_log_pub, "Mission rejected: Add Takeoff item or remove Landing.\t");
-			events::send(events::ID("navigator_mis_add_to_or_rm_land"), {events::Log::Error, events::LogInternal::Info},
-				     "Mission rejected: Add Takeoff item or remove Landing");
+			if (!result) {
+				mavlink_log_critical(_mavlink_log_pub, "Mission rejected: Landing waypoint/pattern required.");
+				events::send(events::ID("feasibility_mis_in_air_landing_req"), {events::Log::Error, events::LogInternal::Info},
+					     "Mission rejected: Landing waypoint/pattern required");
+			}
+
+		} else {
+			result = hasMissionBothOrNeitherTakeoffAndLanding();
 		}
 
 		break;
@@ -600,6 +611,23 @@ bool FeasibilityChecker::checkTakeoffLandAvailable()
 	return result;
 }
 
+bool FeasibilityChecker::hasMissionBothOrNeitherTakeoffAndLanding()
+{
+	bool result{_has_takeoff == _landing_valid};
+
+	if (!result && (_has_takeoff)) {
+		mavlink_log_critical(_mavlink_log_pub, "Mission rejected: Add Landing item or remove Takeoff.\t");
+		events::send(events::ID("navigator_mis_add_land_or_rm_to"), {events::Log::Error, events::LogInternal::Info},
+			     "Mission rejected: Add Landing item or remove Takeoff");
+
+	} else if (!result && (_landing_valid)) {
+		mavlink_log_critical(_mavlink_log_pub, "Mission rejected: Add Takeoff item or remove Landing.\t");
+		events::send(events::ID("navigator_mis_add_to_or_rm_land"), {events::Log::Error, events::LogInternal::Info},
+			     "Mission rejected: Add Takeoff item or remove Landing");
+	}
+
+	return result;
+}
 
 bool FeasibilityChecker::checkHorizontalDistanceToFirstWaypoint(mission_item_s &mission_item)
 {

src/modules/navigator/MissionFeasibility/FeasibilityChecker.hpp

@@ -36,6 +36,7 @@
 #include "../navigation.h"
 #include <mathlib/mathlib.h>
 #include <uORB/topics/home_position.h>
+#include <uORB/topics/rtl_status.h>
 #include <uORB/topics/vehicle_status.h>
 #include <uORB/topics/vehicle_global_position.h>
 #include <uORB/topics/vehicle_land_detected.h>
@@ -97,6 +98,7 @@ class FeasibilityChecker : public ModuleParams
 	uORB::Subscription _status_sub{ORB_ID(vehicle_status)};
 	uORB::Subscription _land_detector_sub{ORB_ID(vehicle_land_detected)};
 	uORB::Subscription _vehicle_global_position_sub{ORB_ID(vehicle_global_position)};
+	uORB::Subscription _rtl_status_sub{ORB_ID(rtl_status)};
 
 	// parameters
 	float _param_fw_lnd_ang{0.f};
@@ -106,6 +108,7 @@ class FeasibilityChecker : public ModuleParams
 
 	bool _is_landed{false};
 	float _home_alt_msl{NAN};
+	bool _has_vtol_approach{false};
 	matrix::Vector2d _home_lat_lon = matrix::Vector2d((double)NAN, (double)NAN);
 	matrix::Vector2d _current_position_lat_lon = matrix::Vector2d((double)NAN, (double)NAN);
 	VehicleType _vehicle_type{VehicleType::RotaryWing};
@@ -247,4 +250,8 @@ class FeasibilityChecker : public ModuleParams
 	 * @return False if the check failed.
 	*/
 	void doMulticopterChecks(mission_item_s &mission_item, const int current_index);
+
+	// Helper functions
+
+	bool hasMissionBothOrNeitherTakeoffAndLanding();
 };

src/modules/navigator/mission_params.c

@@ -68,6 +68,7 @@ PARAM_DEFINE_FLOAT(MIS_TAKEOFF_ALT, 2.5f);
  * @value 2 Require a landing
  * @value 3 Require a takeoff and a landing
  * @value 4 Require both a takeoff and a landing, or neither
+ * @value 5 Same as previous, but require a landing if in air and no valid VTOL landing approach is present
  * @group Mission
  */
 PARAM_DEFINE_INT32(MIS_TKO_LAND_REQ, 0);