refactor(commander): remove duplicate failure_detector_status from vehicle_status (#26754)

The failure_detector_status bitmask in vehicle_status duplicates the
separate FailureDetectorStatus topic. Remove it and read directly from
the dedicated topic in failureDetectorCheck and HIGH_LATENCY2.

src/modules/commander/Commander.cpp

@@ -1925,7 +1925,6 @@ void Commander::run()
 
 		// Check for failure detector status
 		if (_failure_detector.update(_vehicle_status, _vehicle_control_mode)) {
-			_vehicle_status.failure_detector_status = _failure_detector.getStatus().value;
 			_status_changed = true;
 		}
 
@@ -1998,7 +1997,7 @@ void Commander::run()
 			send_parachute_command();
 		}
 
-		// publish states (armed, control_mode, vehicle_status, failure_detector_status) at 2 Hz or immediately when changed
+		// publish states (armed, control_mode, vehicle_status) at 2 Hz or immediately when changed
 		if ((now >= _vehicle_status.timestamp + 500_ms) || _status_changed || nav_state_or_failsafe_changed
 		    || !(_actuator_armed == actuator_armed_prev)) {
 

src/modules/commander/HealthAndArmingChecks/checks/failureDetectorCheck.cpp

@@ -35,7 +35,13 @@
 
 void FailureDetectorChecks::checkAndReport(const Context &context, Report &reporter)
 {
-	if (context.status().failure_detector_status & vehicle_status_s::FAILURE_ROLL) {
+	failure_detector_status_s fd_status;
+
+	if (!_failure_detector_status_sub.copy(&fd_status)) {
+		return;
+	}
+
+	if (fd_status.fd_roll) {
 		/* EVENT
 		 * @description
 		 * The vehicle exceeded the maximum configured roll angle.
@@ -51,7 +57,7 @@ void FailureDetectorChecks::checkAndReport(const Context &context, Report &repor
 			mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Attitude failure (roll)");
 		}
 
-	} else if (context.status().failure_detector_status & vehicle_status_s::FAILURE_PITCH) {
+	} else if (fd_status.fd_pitch) {
 		/* EVENT
 		 * @description
 		 * The vehicle exceeded the maximum configured pitch angle.
@@ -68,7 +74,7 @@ void FailureDetectorChecks::checkAndReport(const Context &context, Report &repor
 		}
 	}
 
-	if (context.status().failure_detector_status & vehicle_status_s::FAILURE_ALT) {
+	if (fd_status.fd_alt) {
 		/* EVENT
 		 */
 		reporter.armingCheckFailure(NavModes::All, health_component_t::system, events::ID("check_failure_detector_alt"),
@@ -79,7 +85,7 @@ void FailureDetectorChecks::checkAndReport(const Context &context, Report &repor
 		}
 	}
 
-	if (context.status().failure_detector_status & vehicle_status_s::FAILURE_EXT) {
+	if (fd_status.fd_ext) {
 		/* EVENT
 		 * @description
 		 * <profile name="dev">
@@ -94,12 +100,10 @@ void FailureDetectorChecks::checkAndReport(const Context &context, Report &repor
 		}
 	}
 
-	reporter.failsafeFlags().fd_critical_failure = context.status().failure_detector_status &
-			(vehicle_status_s::FAILURE_ROLL | vehicle_status_s::FAILURE_PITCH | vehicle_status_s::FAILURE_ALT |
-			 vehicle_status_s::FAILURE_EXT);
+	reporter.failsafeFlags().fd_critical_failure = fd_status.fd_roll || fd_status.fd_pitch || fd_status.fd_alt ||
+			fd_status.fd_ext;
 
-	reporter.failsafeFlags().fd_imbalanced_prop = context.status().failure_detector_status &
-			vehicle_status_s::FAILURE_IMBALANCED_PROP;
+	reporter.failsafeFlags().fd_imbalanced_prop = fd_status.fd_imbalanced_prop;
 
 	if (reporter.failsafeFlags().fd_imbalanced_prop) {
 		/* EVENT

src/modules/commander/HealthAndArmingChecks/checks/failureDetectorCheck.hpp

@@ -35,6 +35,8 @@
 
 #include "../Common.hpp"
 
+#include <uORB/Subscription.hpp>
+#include <uORB/topics/failure_detector_status.h>
 
 class FailureDetectorChecks : public HealthAndArmingCheckBase
 {
@@ -45,4 +47,5 @@ public:
 	void checkAndReport(const Context &context, Report &reporter) override;
 
 private:
+	uORB::Subscription _failure_detector_status_sub{ORB_ID(failure_detector_status)};
 };

src/modules/mavlink/streams/HIGH_LATENCY2.hpp

@@ -55,6 +55,7 @@
 #include <uORB/topics/vehicle_local_position.h>
 #include <uORB/topics/vehicle_attitude.h>
 #include <uORB/topics/vehicle_status.h>
+#include <uORB/topics/failure_detector_status.h>
 #include <uORB/topics/failsafe_flags.h>
 #include <uORB/topics/health_report.h>
 #include <uORB/topics/vehicle_air_data.h>
@@ -135,6 +136,7 @@ private:
 			updated |= write_heading_if_updated(&msg);
 			updated |= write_mission_result_if_updated(&msg);
 			updated |= write_failsafe_flags(&msg);
+			updated |= write_failure_detector_status(&msg);
 
 			// these topics are already updated in update_data() and thus we just copy them here
 			write_airspeed(&msg);
@@ -454,10 +456,6 @@ private:
 				}
 			}
 
-			if (status.failure_detector_status & vehicle_status_s::FAILURE_MOTOR) {
-				msg->failure_flags |= HL_FAILURE_FLAG_ENGINE;
-			}
-
 			// flight mode
 			union px4_custom_mode custom_mode {get_px4_custom_mode(status.nav_state)};
 			msg->custom_mode = custom_mode.custom_mode_hl;
@@ -492,6 +490,21 @@ private:
 		return false;
 	}
 
+	bool write_failure_detector_status(mavlink_high_latency2_t *msg)
+	{
+		failure_detector_status_s fd_status;
+
+		if (_failure_detector_status_sub.update(&fd_status)) {
+			if (fd_status.fd_motor) {
+				msg->failure_flags |= HL_FAILURE_FLAG_ENGINE;
+			}
+
+			return true;
+		}
+
+		return false;
+	}
+
 	bool write_wind(mavlink_high_latency2_t *msg)
 	{
 		wind_s wind;
@@ -665,6 +678,7 @@ private:
 	uORB::Subscription _gps_sub{ORB_ID(vehicle_gps_position)};
 	uORB::Subscription _mission_result_sub{ORB_ID(mission_result)};
 	uORB::Subscription _status_sub{ORB_ID(vehicle_status)};
+	uORB::Subscription _failure_detector_status_sub{ORB_ID(failure_detector_status)};
 	uORB::Subscription _failsafe_flags_sub{ORB_ID(failsafe_flags)};
 	uORB::Subscription _tecs_status_sub{ORB_ID(tecs_status)};
 	uORB::Subscription _wind_sub{ORB_ID(wind)};