launch: add launch specific idle throttle param

src/modules/fw_pos_control_l1/FixedwingPositionControl.cpp

@@ -1060,7 +1060,7 @@ FixedwingPositionControl::control_position(const Vector2f &curr_pos, const Vecto
 		/* making sure again that the correct thrust is used,
 		 * without depending on library calls for safety reasons.
 		   the pre-takeoff throttle and the idle throttle normally map to the same parameter. */
-		_att_sp.thrust = _parameters.throttle_idle;
+		_att_sp.thrust = _launchDetector.getThrottleIdle(_parameters.throttle_idle);
 
 	} else if (_control_mode_current == FW_POSCTRL_MODE_AUTO &&
 		   pos_sp_curr.type == position_setpoint_s::SETPOINT_TYPE_TAKEOFF &&
@@ -1078,7 +1078,8 @@ FixedwingPositionControl::control_position(const Vector2f &curr_pos, const Vecto
 
 	} else {
 		/* Copy thrust and pitch values from tecs */
-		if (_vehicle_land_detected.landed) {
+		if (_vehicle_land_detected.landed && !(_launch_detection_state == LAUNCHDETECTION_RES_DETECTED_ENABLEMOTORS
+						       && pos_sp_curr.type == position_setpoint_s::SETPOINT_TYPE_TAKEOFF)) {
 			// when we are landed state we want the motor to spin at idle speed
 			_att_sp.thrust = min(_parameters.throttle_idle, throttle_max);
 
@@ -1231,7 +1232,7 @@ FixedwingPositionControl::control_takeoff(const Vector2f &curr_pos, const Vector
 			float takeoff_throttle = _parameters.throttle_max;
 
 			if (_launch_detection_state != LAUNCHDETECTION_RES_DETECTED_ENABLEMOTORS) {
-				takeoff_throttle = _parameters.throttle_idle;
+				takeoff_throttle = _launchDetector.getThrottleIdle(_parameters.throttle_idle);
 			}
 
 			/* select maximum pitch: the launchdetector may impose another limit for the pitch
@@ -1820,7 +1821,9 @@ FixedwingPositionControl::tecs_update_pitch_throttle(float alt_sp, float airspee
 	_last_tecs_update = hrt_absolute_time();
 
 	// do not run TECS if we are not in air
-	bool run_tecs = !_vehicle_land_detected.landed;
+	bool run_tecs = !_vehicle_land_detected.landed || (_launch_detection_state == LAUNCHDETECTION_RES_DETECTED_ENABLEMOTORS
+			&& mode == tecs_status_s::TECS_MODE_TAKEOFF);
+	// handles case of land detected / launch detected interference during take-off
 
 	// do not run TECS if vehicle is a VTOL and we are in rotary wing mode or in transition
 	// (it should also not run during VTOL blending because airspeed is too low still)
@@ -1896,10 +1899,12 @@ FixedwingPositionControl::tecs_update_pitch_throttle(float alt_sp, float airspee
 	}
 
 	/* tell TECS to update its state, but let it know when it cannot actually control the plane */
-	bool in_air_alt_control = (!_vehicle_land_detected.landed &&
-				   (_control_mode.flag_control_auto_enabled ||
-				    _control_mode.flag_control_velocity_enabled ||
-				    _control_mode.flag_control_altitude_enabled));
+	bool in_air_alt_control = ((!_vehicle_land_detected.landed ||
+				    (_launch_detection_state == LAUNCHDETECTION_RES_DETECTED_ENABLEMOTORS
+				     && mode == tecs_status_s::TECS_MODE_TAKEOFF))
+				   && (_control_mode.flag_control_auto_enabled
+				       || _control_mode.flag_control_velocity_enabled
+				       || _control_mode.flag_control_altitude_enabled));
 
 	/* update TECS vehicle state estimates */
 	_tecs.update_vehicle_state_estimates(_airspeed, _R_nb,

src/modules/fw_pos_control_l1/launchdetection/CatapultLaunchMethod.cpp

@@ -124,4 +124,11 @@ float CatapultLaunchMethod::getPitchMax(float pitchMaxDefault)
 	}
 }
 
+float CatapultLaunchMethod::getThrottleIdle(float throttleIdleDefault)
+{
+	// use operator defined launching idle (ignore default idle)
+	return _throttleIdle.get();
+}
+
+
 } // namespace launchdetection

src/modules/fw_pos_control_l1/launchdetection/CatapultLaunchMethod.h

@@ -59,6 +59,7 @@ class CatapultLaunchMethod : public LaunchMethod, public ModuleParams
 	LaunchDetectionResult getLaunchDetected() const override;
 	void reset() override;
 	float getPitchMax(float pitchMaxDefault) override;
+	float getThrottleIdle(float throttleIdleDefault) override;
 
 private:
 	hrt_abstime _last_timestamp{0};
@@ -71,9 +72,10 @@ class CatapultLaunchMethod : public LaunchMethod, public ModuleParams
 		(ParamFloat<px4::params::LAUN_CAT_A>) _thresholdAccel,
 		(ParamFloat<px4::params::LAUN_CAT_T>) _thresholdTime,
 		(ParamFloat<px4::params::LAUN_CAT_MDEL>) _motorDelay,
-		(ParamFloat<px4::params::LAUN_CAT_PMAX>) _pitchMaxPreThrottle /**< Upper pitch limit before throttle is turned on.
+		(ParamFloat<px4::params::LAUN_CAT_PMAX>) _pitchMaxPreThrottle, /**< Upper pitch limit before throttle is turned on.
 						       Can be used to make sure that the AC does not climb
 						       too much while attached to a bungee */
+		(ParamFloat<px4::params::LAUN_THR_IDLE>) _throttleIdle
 	)
 
 };

src/modules/fw_pos_control_l1/launchdetection/LaunchDetector.cpp

@@ -119,4 +119,25 @@ float LaunchDetector::getPitchMax(float pitchMaxDefault)
 	}
 }
 
+float LaunchDetector::getThrottleIdle(float throttleIdleDefault)
+{
+	if (!launchDetectionEnabled()) {
+		return throttleIdleDefault;
+	}
+
+	/* if a lauchdetectionmethod is active or only one exists return the idle throttle from this method,
+	 * otherwise use the default */
+	if (_activeLaunchDetectionMethodIndex < 0) {
+		if (sizeof(_launchMethods) / sizeof(LaunchMethod *) > 1) {
+			return throttleIdleDefault;
+
+		} else {
+			return _launchMethods[0]->getThrottleIdle(throttleIdleDefault);
+		}
+
+	} else {
+		return _launchMethods[_activeLaunchDetectionMethodIndex]->getThrottleIdle(throttleIdleDefault);
+	}
+}
+
 } // namespace launchdetection

src/modules/fw_pos_control_l1/launchdetection/LaunchDetector.h

@@ -64,6 +64,8 @@ class __EXPORT LaunchDetector : public ModuleParams
 
 	/* Returns a maximum pitch in deg. Different launch methods may impose upper pitch limits during launch */
 	float getPitchMax(float pitchMaxDefault);
+	/* Returns an idle throttle specific to the pre- "motors enabled" launch detection phase */
+	float getThrottleIdle(float throttleIdleDefault);
 
 private:
 	/* holds an index to the launchMethod in the array _launchMethods

src/modules/fw_pos_control_l1/launchdetection/LaunchMethod.h

@@ -65,6 +65,8 @@ class LaunchMethod
 
 	/* Returns a upper pitch limit if required, otherwise returns pitchMaxDefault */
 	virtual float getPitchMax(float pitchMaxDefault) = 0;
+	/* Returns an idle throttle specific to the pre- "motors enabled" launch detection phase */
+	virtual float getThrottleIdle(float throttleIdleDefault) = 0;
 
 };
 

src/modules/fw_pos_control_l1/launchdetection/launchdetection_params.c

@@ -108,3 +108,14 @@ PARAM_DEFINE_FLOAT(LAUN_CAT_MDEL, 0.0f);
  * @group FW Launch detection
  */
 PARAM_DEFINE_FLOAT(LAUN_CAT_PMAX, 30.0f);
+
+/**
+ * Idle throttle setting during launch detection before motors enabled.
+ *
+ * @min 0.0
+ * @max 1.0
+ * @decimal 2
+ * @increment 0.05
+ * @group FW Launch detection
+ */
+PARAM_DEFINE_FLOAT(LAUN_THR_IDLE, 0.0f);