FW Pos C: add option to disable airspeed setpoint via stick input

-rename FW_POSCTL_INV_ST to FW_POS_STK_CONF and make bitmask out of it:
  - bit 0: alternative mapping (height rate on throttle stick, airspeed on pitch)
  - bit 1: enable/disable airspeed setpoints via stick

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

src/modules/fw_pos_control_l1/FixedwingPositionControl.cpp

@@ -325,13 +325,19 @@ FixedwingPositionControl::manual_control_setpoint_poll()
 	_manual_control_setpoint_altitude = _manual_control_setpoint.x;
 	_manual_control_setpoint_airspeed = math::constrain(_manual_control_setpoint.z, 0.0f, 1.0f);
 
-	if (_param_fw_posctl_inv_st.get()) {
+	if (_param_fw_pos_stk_conf.get() & STICK_CONFIG_SWAP_STICKS_BIT) {
 		/* Alternate stick allocation (similar concept as for multirotor systems:
 		 * demanding up/down with the throttle stick, and move faster/break with the pitch one.
 		 */
 		_manual_control_setpoint_altitude = -(math::constrain(_manual_control_setpoint.z, 0.0f, 1.0f) * 2.f - 1.f);
 		_manual_control_setpoint_airspeed = math::constrain(_manual_control_setpoint.x, -1.0f, 1.0f) / 2.f + 0.5f;
 	}
+
+	// send neutral setpoints if no update for 1 s
+	if (hrt_elapsed_time(&_manual_control_setpoint.timestamp) > 1_s) {
+		_manual_control_setpoint_altitude = 0.f;
+		_manual_control_setpoint_airspeed = 0.5f;
+	}
 }
 
 
@@ -375,20 +381,22 @@ FixedwingPositionControl::vehicle_attitude_poll()
 float
 FixedwingPositionControl::get_manual_airspeed_setpoint()
 {
-	float altctrl_airspeed = 0;
+	float altctrl_airspeed = _param_fw_airspd_trim.get();
 
-	// neutral throttle corresponds to trim airspeed
+	if (_param_fw_pos_stk_conf.get() & STICK_CONFIG_ENABLE_AIRSPEED_SP_MANUAL_BIT) {
-	if (_manual_control_setpoint_airspeed < 0.5f) {
+		// neutral throttle corresponds to trim airspeed
-		// lower half of throttle is min to trim airspeed
+		if (_manual_control_setpoint_airspeed < 0.5f) {
-		altctrl_airspeed = _param_fw_airspd_min.get() +
+			// lower half of throttle is min to trim airspeed
-				   (_param_fw_airspd_trim.get() - _param_fw_airspd_min.get()) *
+			altctrl_airspeed = _param_fw_airspd_min.get() +
-				   _manual_control_setpoint_airspeed * 2;
+					   (_param_fw_airspd_trim.get() - _param_fw_airspd_min.get()) *
+					   _manual_control_setpoint_airspeed * 2;
 
-	} else {
+		} else {
-		// upper half of throttle is trim to max airspeed
+			// upper half of throttle is trim to max airspeed
-		altctrl_airspeed = _param_fw_airspd_trim.get() +
+			altctrl_airspeed = _param_fw_airspd_trim.get() +
-				   (_param_fw_airspd_max.get() - _param_fw_airspd_trim.get()) *
+					   (_param_fw_airspd_max.get() - _param_fw_airspd_trim.get()) *
-				   (_manual_control_setpoint_airspeed * 2 - 1);
+					   (_manual_control_setpoint_airspeed * 2 - 1);
+		}
 	}
 
 	return altctrl_airspeed;

src/modules/fw_pos_control_l1/FixedwingPositionControl.hpp

@@ -286,6 +286,11 @@ private:
 	param_t _param_handle_airspeed_trans{PARAM_INVALID};
 	float _param_airspeed_trans{NAN};
 
+	enum StickConfig {
+		STICK_CONFIG_SWAP_STICKS_BIT = (1 << 0),
+		STICK_CONFIG_ENABLE_AIRSPEED_SP_MANUAL_BIT = (1 << 1)
+	};
+
 	// Update our local parameter cache.
 	int		parameters_update();
 
@@ -461,7 +466,7 @@ private:
 		(ParamFloat<px4::params::FW_THR_MIN>) _param_fw_thr_min,
 		(ParamFloat<px4::params::FW_THR_SLEW_MAX>) _param_fw_thr_slew_max,
 
-		(ParamBool<px4::params::FW_POSCTL_INV_ST>) _param_fw_posctl_inv_st,
+		(ParamInt<px4::params::FW_POS_STK_CONF>) _param_fw_pos_stk_conf,
 
 		(ParamInt<px4::params::FW_GPSF_LT>) _param_nav_gpsf_lt,
 		(ParamFloat<px4::params::FW_GPSF_R>) _param_nav_gpsf_r,

src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c

@@ -885,17 +885,17 @@ PARAM_DEFINE_FLOAT(FW_T_TAS_TC, 5.0f);
 PARAM_DEFINE_FLOAT(FW_GND_SPD_MIN, 5.0f);
 
 /**
- * RC stick mapping fixed-wing.
+ * RC stick configuraton fixed-wing.
  *
- * Set RC/joystick configuration for fixed-wing position and altitude controlled flight.
+ * Set RC/joystick configuration for fixed-wing manual position and altitude controlled flight.
  *
  * @min 0
- * @max 1
+ * @max 3
- * @value 0 Normal stick configuration (airspeed on throttle stick, altitude on pitch stick)
+ * @bit 0 Alternative stick configuration (height rate on throttle stick, airspeed on pitch stick)
- * @value 1 Alternative stick configuration (altitude on throttle stick, airspeed on pitch stick)
+ * @bit 1 Enable airspeed setpoint via sticks in altitude and position flight mode
  * @group FW L1 Control
  */
-PARAM_DEFINE_INT32(FW_POSCTL_INV_ST, 0);
+PARAM_DEFINE_INT32(FW_POS_STK_CONF, 2);
 
 /**
  * Specific total energy rate first order filter time constant.