FW Land Detector: force to landed if currently landed and in launch process

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>

src/modules/fw_pos_control_l1/launchdetection/LaunchDetector.h

@@ -99,9 +99,6 @@ private:
 	 */
 	uint _state{launch_detection_status_s::STATE_WAITING_FOR_LAUNCH};
 
-	// [us] logs the last time the launch detection notification was sent (used not to spam notifications during launch detection)
-	hrt_abstime _last_time_launch_detection_notified{0};
-
 	DEFINE_PARAMETERS(
 		(ParamBool<px4::params::LAUN_ALL_ON>) _param_laun_all_on,
 		(ParamFloat<px4::params::LAUN_CAT_A>) _param_laun_cat_a,

src/modules/land_detector/FixedwingLandDetector.cpp

@@ -60,7 +60,16 @@ bool FixedwingLandDetector::_get_landed_state()
 
 	bool landDetected = false;
 
-	if (hrt_elapsed_time(&_vehicle_local_position.timestamp) < 1_s) {
+	launch_detection_status_s launch_detection_status{};
+	_launch_detection_status_sub.copy(&launch_detection_status);
+
+	// force the landed state to stay landed if we're currently in the catapult/hand-launch launch process. Detect that we are in this state
+	// by checking if the last publication of launch_detection_status is less than 0.5s old, and we're not yet in the flying state.
+	if (_landed_hysteresis.get_state() &&  hrt_elapsed_time(&launch_detection_status.timestamp) < 500_ms
+	    && launch_detection_status.launch_detection_state < launch_detection_status_s::STATE_FLYING) {
+		landDetected = true;
+
+	} else if (hrt_elapsed_time(&_vehicle_local_position.timestamp) < 1_s) {
 
 		// Horizontal velocity complimentary filter.
 		float val = 0.97f * _velocity_xy_filtered + 0.03f * sqrtf(_vehicle_local_position.vx * _vehicle_local_position.vx +

src/modules/land_detector/FixedwingLandDetector.h

@@ -44,6 +44,7 @@
 
 #include <matrix/math.hpp>
 #include <uORB/topics/airspeed_validated.h>
+#include <uORB/topics/launch_detection_status.h>
 
 #include "LandDetector.h"
 
@@ -68,6 +69,7 @@ private:
 	static constexpr hrt_abstime FLYING_TRIGGER_TIME_US = 0_us;
 
 	uORB::Subscription _airspeed_validated_sub{ORB_ID(airspeed_validated)};
+	uORB::Subscription _launch_detection_status_sub{ORB_ID(launch_detection_status)};
 
 	float _airspeed_filtered{0.0f};
 	float _velocity_xy_filtered{0.0f};