feat(commander): add Remote ID in-flight failsafe

Extend COM_ARM_ODID into a unified arming + in-flight failsafe parameter (0 = Disabled, 1 = Warning, 2 = Return, 3 = Land, 4 = Terminate)

Values >= 2 block arming and trigger the configured action if Remote ID
is lost while airborne.

msg/FailsafeFlags.msg

@@ -59,3 +59,4 @@ bool flight_time_limit_exceeded       # Maximum flight time exceeded
 bool position_accuracy_low            # Position estimate has dropped below threshold, but is currently still declared valid
 bool navigator_failure        	      # Navigator failed to execute a mode
 bool parachute_unhealthy              # Parachute system missing or unhealthy
+bool remote_id_unhealthy              # Remote ID (Open Drone ID) system missing or unhealthy

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

@@ -36,17 +36,17 @@
 
 void OpenDroneIDChecks::checkAndReport(const Context &context, Report &reporter)
 {
-	// Check to see if the check has been disabled
+	reporter.failsafeFlags().remote_id_unhealthy =
+		!context.status().open_drone_id_system_present ||
+		!context.status().open_drone_id_system_healthy;
+
 	if (!_param_com_arm_odid.get()) {
 		return;
 	}
 
-	NavModes affected_modes{NavModes::None};
-
-	if (_param_com_arm_odid.get() == 2) {
-		// disallow arming without the Open Drone ID system
-		affected_modes = NavModes::All;
-	}
+	const bool is_error = _param_com_arm_odid.get() >= 2;
+	const NavModes affected_modes = is_error ? NavModes::All : NavModes::None;
+	const events::Log log_level = is_error ? events::Log::Error : events::Log::Warning;
 
 	if (!context.status().open_drone_id_system_present) {
 		/* EVENT
@@ -57,9 +57,9 @@ void OpenDroneIDChecks::checkAndReport(const Context &context, Report &reporter)
 		 * This check can be configured via <param>COM_ARM_ODID</param> parameter.
 		 * </profile>
 		 */
-		reporter.armingCheckFailure(affected_modes, health_component_t::open_drone_id,
-					    events::ID("check_open_drone_id_missing"),
-					    events::Log::Error, "Open Drone ID system missing");
+		reporter.healthFailure(affected_modes, health_component_t::open_drone_id,
+				       events::ID("check_open_drone_id_missing"),
+				       log_level, "Open Drone ID system missing");
 
 		if (reporter.mavlink_log_pub()) {
 			mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Open Drone ID system missing");
@@ -74,9 +74,9 @@ void OpenDroneIDChecks::checkAndReport(const Context &context, Report &reporter)
 		 * This check can be configured via <param>COM_ARM_ODID</param> parameter.
 		 * </profile>
 		 */
-		reporter.armingCheckFailure(affected_modes, health_component_t::open_drone_id,
-					    events::ID("check_open_drone_id_unhealthy"),
-					    events::Log::Error, "Open Drone ID system not ready");
+		reporter.healthFailure(affected_modes, health_component_t::open_drone_id,
+				       events::ID("check_open_drone_id_unhealthy"),
+				       log_level, "Open Drone ID system not ready");
 
 		if (reporter.mavlink_log_pub()) {
 			mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Open Drone ID system not ready");

src/modules/commander/commander_params.yaml

@@ -612,17 +612,24 @@ parameters:
       default: 1
     COM_ARM_ODID:
       description:
-        short: Enable Drone ID system detection and health check
+        short: Open Drone ID system check and in-flight failsafe
         long: |-
-          This check detects if the Open Drone ID system is missing.
-          Depending on the value of the parameter, the check can be
-          disabled, warn only or deny arming.
+          Configures both the arming check and the in-flight failsafe for the
+          Open Drone ID (Remote ID) system.
+
+          Warning: warns at arming but does not block it, and takes no in-flight action.
+          Land / Return / Terminate: block arming without the ODID system present and
+          healthy, and trigger the corresponding failsafe action if the system is lost
+          while airborne (heartbeat timeout > 3 s).
       type: enum
       values:
         0: Disabled
         1: Warning only
-        2: Enforce Open Drone ID system presence
+        2: Return
+        3: Land
+        4: Terminate
       default: 0
+      increment: 1
     COM_ARM_TRAFF:
       description:
         short: Enable Traffic Avoidance system detection check

src/modules/commander/failsafe/failsafe.cpp

@@ -442,6 +442,37 @@ FailsafeBase::ActionOptions Failsafe::fromRemainingFlightTimeLowActParam(int par
 	return options;
 }
 
+FailsafeBase::ActionOptions Failsafe::fromOdidFailActParam(int param_value)
+{
+	ActionOptions options{};
+
+	switch (open_drone_id_failsafe_mode(param_value)) {
+	case open_drone_id_failsafe_mode::Return_mode:
+		options.action = Action::RTL;
+		options.clear_condition = ClearCondition::OnModeChangeOrDisarm;
+		break;
+
+	case open_drone_id_failsafe_mode::Land_mode:
+		options.action = Action::Land;
+		options.clear_condition = ClearCondition::OnModeChangeOrDisarm;
+		break;
+
+	case open_drone_id_failsafe_mode::Terminate:
+		options.allow_user_takeover = UserTakeoverAllowed::Never;
+		options.action = Action::Terminate;
+		options.clear_condition = ClearCondition::Never;
+		break;
+
+	case open_drone_id_failsafe_mode::Disabled:
+	case open_drone_id_failsafe_mode::Warning:
+	default:
+		options.action = Action::None;
+		break;
+	}
+
+	return options;
+}
+
 bool Failsafe::isFailsafeIgnored(uint8_t user_intended_mode, int32_t exception_mask_parameter)
 {
 	switch (user_intended_mode) {
@@ -577,6 +608,11 @@ void Failsafe::checkStateAndMode(const hrt_abstime &time_us, const State &state,
 	// Parachute system health failsafe
 	CHECK_FAILSAFE(status_flags, parachute_unhealthy, Action::RTL);
 
+	// Remote ID (Open Drone ID) loss failsafe
+	if (state.armed && _param_com_arm_odid.get() >= int32_t(open_drone_id_failsafe_mode::Return_mode)) {
+		CHECK_FAILSAFE(status_flags, remote_id_unhealthy, fromOdidFailActParam(_param_com_arm_odid.get()));
+	}
+
 	// Battery low failsafe
 	// If battery was low and arming was allowed through COM_ARM_BAT_MIN, don't failsafe immediately for the current low battery warning state
 	const bool warning_worse_than_at_arming = (status_flags.battery_warning > _battery_warning_at_arming);

src/modules/commander/failsafe/failsafe.h

@@ -157,6 +157,14 @@ private:
 		Return_mode = 3
 	};
 
+	enum class open_drone_id_failsafe_mode : int32_t {
+		Disabled = 0,
+		Warning = 1,
+		Return_mode = 2,
+		Land_mode = 3,
+		Terminate = 4,
+	};
+
 	static ActionOptions fromNavDllOrRclActParam(int param_value);
 
 	static ActionOptions fromGfActParam(int param_value);
@@ -168,6 +176,7 @@ private:
 	static ActionOptions fromHighWindLimitActParam(int param_value);
 	static ActionOptions fromPosLowActParam(int param_value);
 	static ActionOptions fromRemainingFlightTimeLowActParam(int param_value);
+	static ActionOptions fromOdidFailActParam(int param_value);
 
 	static bool isFailsafeIgnored(uint8_t user_intended_mode, int32_t exception_mask_parameter);
 
@@ -209,7 +218,8 @@ private:
 					(ParamInt<px4::params::COM_QC_ACT>) _param_com_qc_act,
 					(ParamInt<px4::params::COM_WIND_MAX_ACT>) _param_com_wind_max_act,
 					(ParamInt<px4::params::COM_FLTT_LOW_ACT>) _param_com_fltt_low_act,
-					(ParamInt<px4::params::COM_POS_LOW_ACT>) _param_com_pos_low_act
+					(ParamInt<px4::params::COM_POS_LOW_ACT>) _param_com_pos_low_act,
+					(ParamInt<px4::params::COM_ARM_ODID>) _param_com_arm_odid
 				       );
 
 };