Merge pull request #1222 from PX4/asfilter

Airspeed filtering, reinstate TECS for testing

ROMFS/px4fmu_common/init.d/rc.fw_defaults

@@ -11,4 +11,8 @@ then
 	param set NAV_RTL_ALT 100
 	param set NAV_RTL_LAND_T -1
 	param set NAV_ACCEPT_RAD 50
+	param set FW_T_HRATE_P 0.01
+	param set FW_T_RLL2THR 15
+	param set FW_T_SRATE_P 0.01
+	param set FW_T_TIME_CONST 5
 fi

makefiles/config_aerocore_default.mk

@@ -80,6 +80,7 @@ LIBRARIES	+= lib/mathlib/CMSIS
 MODULES		+= lib/mathlib
 MODULES		+= lib/mathlib/math/filter
 MODULES		+= lib/ecl
+MODULES		+= lib/external_lgpl
 MODULES		+= lib/geo
 MODULES		+= lib/geo_lookup
 MODULES		+= lib/conversion

makefiles/config_px4fmu-v1_default.mk

@@ -108,6 +108,7 @@ LIBRARIES	+= lib/mathlib/CMSIS
 MODULES		+= lib/mathlib
 MODULES		+= lib/mathlib/math/filter
 MODULES		+= lib/ecl
+MODULES		+= lib/external_lgpl
 MODULES		+= lib/geo
 MODULES		+= lib/geo_lookup
 MODULES		+= lib/conversion

makefiles/config_px4fmu-v2_default.mk

@@ -121,6 +121,7 @@ LIBRARIES	+= lib/mathlib/CMSIS
 MODULES		+= lib/mathlib
 MODULES		+= lib/mathlib/math/filter
 MODULES		+= lib/ecl
+MODULES		+= lib/external_lgpl
 MODULES		+= lib/geo
 MODULES		+= lib/geo_lookup
 MODULES		+= lib/conversion

src/drivers/meas_airspeed/meas_airspeed.cpp

@@ -92,7 +92,7 @@
 #include <drivers/airspeed/airspeed.h>
 
 /* I2C bus address is 1010001x */
-#define I2C_ADDRESS_MS4525DO	0x28	//0x51 /* 7-bit address. */
+#define I2C_ADDRESS_MS4525DO	0x28	/**< 7-bit address. Depends on the order code (this is for code "I") */
 #define PATH_MS4525		"/dev/ms4525"
 /* The MS5525DSO address is 111011Cx, where C is the complementary value of the pin CSB */
 #define I2C_ADDRESS_MS5525DSO	0x77	//0x77/* 7-bit address, addr. pin pulled low */
@@ -102,9 +102,9 @@
 #define ADDR_READ_MR			0x00	/* write to this address to start conversion */
 
 /* Measurement rate is 100Hz */
-#define MEAS_RATE 100.0f
+#define MEAS_RATE 100
-#define MEAS_DRIVER_FILTER_FREQ 3.0f
+#define MEAS_DRIVER_FILTER_FREQ 1.5f
-#define CONVERSION_INTERVAL	(1000000 / 100)	/* microseconds */
+#define CONVERSION_INTERVAL	(1000000 / MEAS_RATE)	/* microseconds */
 
 class MEASAirspeed : public Airspeed
 {

src/lib/ecl/module.mk

@@ -39,3 +39,5 @@ SRCS		 = 	attitude_fw/ecl_pitch_controller.cpp \
 			attitude_fw/ecl_roll_controller.cpp \
 			attitude_fw/ecl_yaw_controller.cpp \
 			l1/ecl_l1_pos_controller.cpp
+
+MAXOPTIMIZATION	 = -Os

src/lib/external_lgpl/module.mk

@@ -46,3 +46,5 @@
 #
 
 SRCS		 = 	tecs/tecs.cpp
+
+MAXOPTIMIZATION	 = -Os

src/modules/controllib/blocks.cpp

@@ -121,6 +121,9 @@ int blockLimitSymTest()
 
 float BlockLowPass::update(float input)
 {
+	if (!isfinite(getState())) {
+		setState(input);
+	}
 	float b = 2 * float(M_PI) * getFCut() * getDt();
 	float a = b / (1 + b);
 	setState(a * input + (1 - a)*getState());

src/modules/controllib/blocks.hpp

@@ -114,7 +114,7 @@ public:
 // methods
 	BlockLowPass(SuperBlock *parent, const char *name) :
 		Block(parent, name),
-		_state(0),
+		_state(0.0f/0.0f /* initialize to invalid val, force into is_finite() check on first call */),
 		_fCut(this, "") // only one parameter, no need to name
 	{};
 	virtual ~BlockLowPass() {};

src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp

@@ -42,8 +42,8 @@
  *    Proceedings of the AIAA Guidance, Navigation and Control
  *    Conference, Aug 2004. AIAA-2004-4900.
  *
- * Implementation for total energy control class:
+ * Original implementation for total energy control class:
- *    Thomas Gubler
+ *    Paul Riseborough and Andrew Tridgell, 2013 (code in lib/external_lgpl)
  *
  * More details and acknowledgements in the referenced library headers.
  *
@@ -87,10 +87,13 @@
 #include <mavlink/mavlink_log.h>
 #include <launchdetection/LaunchDetector.h>
 #include <ecl/l1/ecl_l1_pos_controller.h>
+#include <external_lgpl/tecs/tecs.h>
 #include <drivers/drv_range_finder.h>
 #include "landingslope.h"
 #include "mtecs/mTecs.h"
 
+static int	_control_task = -1;			/**< task handle for sensor task */
+
 
 /**
  * L1 control app start / stop handling function
@@ -115,9 +118,9 @@ public:
 	/**
 	 * Start the sensors task.
 	 *
-	 * @return		OK on success.
+	 * @return	OK on success.
 	 */
-	int		start();
+	static int	start();
 
 	/**
 	 * Task status
@@ -131,7 +134,6 @@ private:
 
 	bool		_task_should_exit;		/**< if true, sensor task should exit */
 	bool		_task_running;			/**< if true, task is running in its mainloop */
-	int		_control_task;			/**< task handle for sensor task */
 
 	int		_global_pos_sub;
 	int		_pos_sp_triplet_sub;
@@ -192,6 +194,7 @@ private:
 	math::Matrix<3, 3> _R_nb;			///< current attitude
 
 	ECL_L1_Pos_Controller				_l1_control;
+	TECS						_tecs;
 	fwPosctrl::mTecs				_mTecs;
 	bool						_was_pos_control_mode;
 
@@ -199,6 +202,21 @@ private:
 		float l1_period;
 		float l1_damping;
 
+		float time_const;
+		float min_sink_rate;
+		float max_sink_rate;
+		float max_climb_rate;
+		float heightrate_p;
+		float speedrate_p;
+		float throttle_damp;
+		float integrator_gain;
+		float vertical_accel_limit;
+		float height_comp_filter_omega;
+		float speed_comp_filter_omega;
+		float roll_throttle_compensation;
+		float speed_weight;
+		float pitch_damping;
+
 		float airspeed_min;
 		float airspeed_trim;
 		float airspeed_max;
@@ -226,6 +244,21 @@ private:
 		param_t l1_period;
 		param_t l1_damping;
 
+		param_t time_const;
+		param_t min_sink_rate;
+		param_t max_sink_rate;
+		param_t max_climb_rate;
+		param_t heightrate_p;
+		param_t speedrate_p;
+		param_t throttle_damp;
+		param_t integrator_gain;
+		param_t vertical_accel_limit;
+		param_t height_comp_filter_omega;
+		param_t speed_comp_filter_omega;
+		param_t roll_throttle_compensation;
+		param_t speed_weight;
+		param_t pitch_damping;
+
 		param_t airspeed_min;
 		param_t airspeed_trim;
 		param_t airspeed_max;
@@ -361,7 +394,6 @@ FixedwingPositionControl::FixedwingPositionControl() :
 	_mavlink_fd(-1),
 	_task_should_exit(false),
 	_task_running(false),
-	_control_task(-1),
 
 /* subscriptions */
 	_global_pos_sub(-1),
@@ -438,6 +470,21 @@ FixedwingPositionControl::FixedwingPositionControl() :
 	_parameter_handles.land_heading_hold_horizontal_distance = param_find("FW_LND_HHDIST");
 	_parameter_handles.range_finder_rel_alt = param_find("FW_LND_RFRALT");
 
+	_parameter_handles.time_const = 			param_find("FW_T_TIME_CONST");
+	_parameter_handles.min_sink_rate = 			param_find("FW_T_SINK_MIN");
+	_parameter_handles.max_sink_rate =			param_find("FW_T_SINK_MAX");
+	_parameter_handles.max_climb_rate =			param_find("FW_T_CLMB_MAX");
+	_parameter_handles.throttle_damp = 			param_find("FW_T_THR_DAMP");
+	_parameter_handles.integrator_gain =			param_find("FW_T_INTEG_GAIN");
+	_parameter_handles.vertical_accel_limit =		param_find("FW_T_VERT_ACC");
+	_parameter_handles.height_comp_filter_omega =		param_find("FW_T_HGT_OMEGA");
+	_parameter_handles.speed_comp_filter_omega =		param_find("FW_T_SPD_OMEGA");
+	_parameter_handles.roll_throttle_compensation = 	param_find("FW_T_RLL2THR");
+	_parameter_handles.speed_weight = 			param_find("FW_T_SPDWEIGHT");
+	_parameter_handles.pitch_damping = 			param_find("FW_T_PTCH_DAMP");
+	_parameter_handles.heightrate_p =			param_find("FW_T_HRATE_P");
+	_parameter_handles.speedrate_p =			param_find("FW_T_SRATE_P");
+
 	/* fetch initial parameter values */
 	parameters_update();
 }
@@ -488,6 +535,22 @@ FixedwingPositionControl::parameters_update()
 
 	param_get(_parameter_handles.throttle_land_max, &(_parameters.throttle_land_max));
 
+	param_get(_parameter_handles.time_const, &(_parameters.time_const));
+	param_get(_parameter_handles.min_sink_rate, &(_parameters.min_sink_rate));
+	param_get(_parameter_handles.max_sink_rate, &(_parameters.max_sink_rate));
+	param_get(_parameter_handles.throttle_damp, &(_parameters.throttle_damp));
+	param_get(_parameter_handles.integrator_gain, &(_parameters.integrator_gain));
+	param_get(_parameter_handles.vertical_accel_limit, &(_parameters.vertical_accel_limit));
+	param_get(_parameter_handles.height_comp_filter_omega, &(_parameters.height_comp_filter_omega));
+	param_get(_parameter_handles.speed_comp_filter_omega, &(_parameters.speed_comp_filter_omega));
+	param_get(_parameter_handles.roll_throttle_compensation, &(_parameters.roll_throttle_compensation));
+	param_get(_parameter_handles.speed_weight, &(_parameters.speed_weight));
+	param_get(_parameter_handles.pitch_damping, &(_parameters.pitch_damping));
+	param_get(_parameter_handles.max_climb_rate, &(_parameters.max_climb_rate));
+
+	param_get(_parameter_handles.heightrate_p, &(_parameters.heightrate_p));
+	param_get(_parameter_handles.speedrate_p, &(_parameters.speedrate_p));
+
 	param_get(_parameter_handles.land_slope_angle, &(_parameters.land_slope_angle));
 	param_get(_parameter_handles.land_H1_virt, &(_parameters.land_H1_virt));
 	param_get(_parameter_handles.land_flare_alt_relative, &(_parameters.land_flare_alt_relative));
@@ -500,6 +563,23 @@ FixedwingPositionControl::parameters_update()
 	_l1_control.set_l1_period(_parameters.l1_period);
 	_l1_control.set_l1_roll_limit(math::radians(_parameters.roll_limit));
 
+	_tecs.set_time_const(_parameters.time_const);
+	_tecs.set_min_sink_rate(_parameters.min_sink_rate);
+	_tecs.set_max_sink_rate(_parameters.max_sink_rate);
+	_tecs.set_throttle_damp(_parameters.throttle_damp);
+	_tecs.set_integrator_gain(_parameters.integrator_gain);
+	_tecs.set_vertical_accel_limit(_parameters.vertical_accel_limit);
+	_tecs.set_height_comp_filter_omega(_parameters.height_comp_filter_omega);
+	_tecs.set_speed_comp_filter_omega(_parameters.speed_comp_filter_omega);
+	_tecs.set_roll_throttle_compensation(_parameters.roll_throttle_compensation);
+	_tecs.set_speed_weight(_parameters.speed_weight);
+	_tecs.set_pitch_damping(_parameters.pitch_damping);
+	_tecs.set_indicated_airspeed_min(_parameters.airspeed_min);
+	_tecs.set_indicated_airspeed_max(_parameters.airspeed_max);
+	_tecs.set_max_climb_rate(_parameters.max_climb_rate);
+	_tecs.set_heightrate_p(_parameters.heightrate_p);
+	_tecs.set_speedrate_p(_parameters.speedrate_p);
+
 	/* sanity check parameters */
 	if (_parameters.airspeed_max < _parameters.airspeed_min ||
 	    _parameters.airspeed_max < 5.0f ||
@@ -561,6 +641,9 @@ FixedwingPositionControl::vehicle_airspeed_poll()
 		}
 	}
 
+	/* update TECS state */
+	_tecs.enable_airspeed(_airspeed_valid);
+
 	return airspeed_updated;
 }
 
@@ -621,7 +704,17 @@ FixedwingPositionControl::vehicle_setpoint_poll()
 void
 FixedwingPositionControl::task_main_trampoline(int argc, char *argv[])
 {
+	l1_control::g_control = new FixedwingPositionControl();
+
+	if (l1_control::g_control == nullptr) {
+		warnx("OUT OF MEM");
+		return;
+	}
+
+	/* only returns on exit */
 	l1_control::g_control->task_main();
+	delete l1_control::g_control;
+	l1_control::g_control = nullptr;
 }
 
 float
@@ -733,6 +826,14 @@ FixedwingPositionControl::control_position(const math::Vector<2> &current_positi
 
 	float eas2tas = 1.0f; // XXX calculate actual number based on current measurements
 
+	/* filter speed and altitude for controller */
+	math::Vector<3> accel_body(_sensor_combined.accelerometer_m_s2);
+	math::Vector<3> accel_earth = _R_nb * accel_body;
+
+	if (!_mTecs.getEnabled()) {
+		_tecs.update_50hz(_global_pos.alt /* XXX might switch to alt err here */, _airspeed.indicated_airspeed_m_s, _R_nb, accel_body, accel_earth);
+	}
+
 	/* define altitude error */
 	float altitude_error = _pos_sp_triplet.current.alt - _global_pos.alt;
 
@@ -758,6 +859,9 @@ FixedwingPositionControl::control_position(const math::Vector<2> &current_positi
 		/* get circle mode */
 		bool was_circle_mode = _l1_control.circle_mode();
 
+		/* restore speed weight, in case changed intermittently (e.g. in landing handling) */
+		_tecs.set_speed_weight(_parameters.speed_weight);
+
 		/* current waypoint (the one currently heading for) */
 		math::Vector<2> next_wp((float)pos_sp_triplet.current.lat, (float)pos_sp_triplet.current.lon);
 
@@ -1066,9 +1170,9 @@ FixedwingPositionControl::control_position(const math::Vector<2> &current_positi
 		_att_sp.thrust = launchDetector.getThrottlePreTakeoff();
 	}
 	else {
-		_att_sp.thrust = math::min(_mTecs.getThrottleSetpoint(), throttle_max);
+		_att_sp.thrust = math::min(_mTecs.getEnabled() ? _mTecs.getThrottleSetpoint() : _tecs.get_throttle_demand(), throttle_max);
 	}
-	_att_sp.pitch_body = _mTecs.getPitchSetpoint();
+	_att_sp.pitch_body = _mTecs.getEnabled() ? _mTecs.getPitchSetpoint() : _tecs.get_pitch_demand();
 
 	if (_control_mode.flag_control_position_enabled) {
 		last_manual = false;
@@ -1084,10 +1188,6 @@ void
 FixedwingPositionControl::task_main()
 {
 
-	/* inform about start */
-	warnx("Initializing..");
-	fflush(stdout);
-
 	/*
 	 * do subscriptions
 	 */
@@ -1248,20 +1348,29 @@ void FixedwingPositionControl::tecs_update_pitch_throttle(float alt_sp, float v_
 		const math::Vector<3> &ground_speed,
 		tecs_mode mode)
 {
-	/* Using mtecs library: prepare arguments for mtecs call */
+	if (_mTecs.getEnabled()) {
-	float flightPathAngle = 0.0f;
+		/* Using mtecs library: prepare arguments for mtecs call */
-	float ground_speed_length = ground_speed.length();
+		float flightPathAngle = 0.0f;
-	if (ground_speed_length > FLT_EPSILON) {
+		float ground_speed_length = ground_speed.length();
-		flightPathAngle = -asinf(ground_speed(2)/ground_speed_length);
+		if (ground_speed_length > FLT_EPSILON) {
-	}
+			flightPathAngle = -asinf(ground_speed(2)/ground_speed_length);
-	fwPosctrl::LimitOverride limitOverride;
+		}
-	if (climbout_mode) {
+		fwPosctrl::LimitOverride limitOverride;
-		limitOverride.enablePitchMinOverride(M_RAD_TO_DEG_F * climbout_pitch_min_rad);
+		if (climbout_mode) {
+			limitOverride.enablePitchMinOverride(M_RAD_TO_DEG_F * climbout_pitch_min_rad);
+		} else {
+			limitOverride.disablePitchMinOverride();
+		}
+		_mTecs.updateAltitudeSpeed(flightPathAngle, altitude, alt_sp, _airspeed.true_airspeed_m_s, v_sp, mode,
+				limitOverride);
 	} else {
-		limitOverride.disablePitchMinOverride();
+		/* Using tecs library */
+		_tecs.update_pitch_throttle(_R_nb, _att.pitch, altitude, alt_sp, v_sp,
+					    _airspeed.indicated_airspeed_m_s, eas2tas,
+					    climbout_mode, climbout_pitch_min_rad,
+					    throttle_min, throttle_max, throttle_cruise,
+					    pitch_min_rad, pitch_max_rad);
 	}
-	_mTecs.updateAltitudeSpeed(flightPathAngle, altitude, alt_sp, _airspeed.true_airspeed_m_s, v_sp, mode,
-			limitOverride);
 }
 
 int
@@ -1295,14 +1404,7 @@ int fw_pos_control_l1_main(int argc, char *argv[])
 		if (l1_control::g_control != nullptr)
 			errx(1, "already running");
 
-		l1_control::g_control = new FixedwingPositionControl;
+		if (OK != FixedwingPositionControl::start()) {
-
-		if (l1_control::g_control == nullptr)
-			errx(1, "alloc failed");
-
-		if (OK != l1_control::g_control->start()) {
-			delete l1_control::g_control;
-			l1_control::g_control = nullptr;
 			err(1, "start failed");
 		}
 

src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c

@@ -154,6 +154,182 @@ PARAM_DEFINE_FLOAT(FW_THR_MIN, 0.0f);
  */
 PARAM_DEFINE_FLOAT(FW_THR_LND_MAX, 1.0f);
 
+/**
+ * Maximum climb rate
+ *
+ * This is the best climb rate that the aircraft can achieve with 
+ * the throttle set to THR_MAX and the airspeed set to the 
+ * default value. For electric aircraft make sure this number can be 
+ * achieved towards the end of flight when the battery voltage has reduced. 
+ * The setting of this parameter can be checked by commanding a positive 
+ * altitude change of 100m in loiter, RTL or guided mode. If the throttle 
+ * required to climb is close to THR_MAX and the aircraft is maintaining 
+ * airspeed, then this parameter is set correctly. If the airspeed starts 
+ * to reduce, then the parameter is set to high, and if the throttle 
+ * demand required to climb and maintain speed is noticeably less than 
+ * FW_THR_MAX, then either FW_T_CLMB_MAX should be increased or 
+ * FW_THR_MAX reduced.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_CLMB_MAX, 5.0f);
+
+/**
+ * Minimum descent rate
+ *
+ * This is the sink rate of the aircraft with the throttle 
+ * set to THR_MIN and flown at the same airspeed as used 
+ * to measure FW_T_CLMB_MAX.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_SINK_MIN, 2.0f);
+
+/**
+ * Maximum descent rate
+ *
+ * This sets the maximum descent rate that the controller will use. 
+ * If this value is too large, the aircraft can over-speed on descent. 
+ * This should be set to a value that can be achieved without 
+ * exceeding the lower pitch angle limit and without over-speeding 
+ * the aircraft.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_SINK_MAX, 5.0f);
+
+/**
+ * TECS time constant
+ *
+ * This is the time constant of the TECS control algorithm (in seconds). 
+ * Smaller values make it faster to respond, larger values make it slower
+ * to respond.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_TIME_CONST, 5.0f);
+
+/**
+ * Throttle damping factor
+ *
+ * This is the damping gain for the throttle demand loop. 
+ * Increase to add damping to correct for oscillations in speed and height.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_THR_DAMP, 0.5f);
+
+/**
+ * Integrator gain
+ *
+ * This is the integrator gain on the control loop. 
+ * Increasing this gain increases the speed at which speed 
+ * and height offsets are trimmed out, but reduces damping and 
+ * increases overshoot.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_INTEG_GAIN, 0.1f);
+
+/**
+ * Maximum vertical acceleration
+ *
+ * This is the maximum vertical acceleration (in metres/second square)
+ * either up or down that the controller will use to correct speed 
+ * or height errors. The default value of 7 m/s/s (equivalent to +- 0.7 g) 
+ * allows for reasonably aggressive pitch changes if required to recover 
+ * from under-speed conditions.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_VERT_ACC, 7.0f);
+
+/**
+ * Complementary filter "omega" parameter for height
+ *
+ * This is the cross-over frequency (in radians/second) of the complementary 
+ * filter used to fuse vertical acceleration and barometric height to obtain 
+ * an estimate of height rate and height. Increasing this frequency weights 
+ * the solution more towards use of the barometer, whilst reducing it weights 
+ * the solution more towards use of the accelerometer data.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_HGT_OMEGA, 3.0f);
+
+/**
+ * Complementary filter "omega" parameter for speed
+ *
+ * This is the cross-over frequency (in radians/second) of the complementary 
+ * filter used to fuse longitudinal acceleration and airspeed to obtain an 
+ * improved airspeed estimate. Increasing this frequency weights the solution
+ * more towards use of the arispeed sensor, whilst reducing it weights the 
+ * solution more towards use of the accelerometer data.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_SPD_OMEGA, 2.0f);
+
+/**
+ * Roll -> Throttle feedforward
+ *
+ * Increasing this gain turn increases the amount of throttle that will 
+ * be used to compensate for the additional drag created by turning. 
+ * Ideally this should be set to  approximately 10 x the extra sink rate 
+ * in m/s created by a 45 degree bank turn. Increase this gain if 
+ * the aircraft initially loses energy in turns and reduce if the 
+ * aircraft initially gains energy in turns. Efficient high aspect-ratio 
+ * aircraft (eg powered sailplanes) can use a lower value, whereas 
+ * inefficient low aspect-ratio models (eg delta wings) can use a higher value.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_RLL2THR, 10.0f);
+
+/**
+ * Speed <--> Altitude priority
+ *
+ * This parameter adjusts the amount of weighting that the pitch control 
+ * applies to speed vs height errors. Setting it to 0.0 will cause the 
+ * pitch control to control height and ignore speed errors. This will 
+ * normally improve height accuracy but give larger airspeed errors. 
+ * Setting it to 2.0 will cause the pitch control loop to control speed 
+ * and ignore height errors. This will normally reduce airspeed errors, 
+ * but give larger height errors. The default value of 1.0 allows the pitch 
+ * control to simultaneously control height and speed. 
+ * Note to Glider Pilots - set this parameter to 2.0 (The glider will 
+ * adjust its pitch angle to maintain airspeed, ignoring changes in height).
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_SPDWEIGHT, 1.0f);
+
+/**
+ * Pitch damping factor
+ *
+ * This is the damping gain for the pitch demand loop. Increase to add 
+ * damping to correct for oscillations in height. The default value of 0.0 
+ * will work well provided the pitch to servo controller has been tuned 
+ * properly.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_PTCH_DAMP, 0.0f);
+
+/**
+ * Height rate P factor
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_HRATE_P, 0.05f);
+
+/**
+ * Speed rate P factor
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_SRATE_P, 0.05f);
+
 /**
  * Landing slope angle
  *

src/modules/fw_pos_control_l1/mtecs/mTecs.cpp

@@ -76,6 +76,7 @@ mTecs::mTecs() :
 	_counter(0),
 	_debug(false)
 {
+	warnx("starting");
 }
 
 mTecs::~mTecs()

src/modules/fw_pos_control_l1/mtecs/mTecs_params.c

@@ -241,7 +241,14 @@ PARAM_DEFINE_FLOAT(MT_FPA_MAX, 30.0f);
  *
  * @group mTECS
  */
-PARAM_DEFINE_FLOAT(MT_A_LP, 1.0f);
+PARAM_DEFINE_FLOAT(MT_A_LP, 0.5f);
+
+/**
+ * Airspeed derivative calculation lowpass
+ *
+ * @group mTECS
+ */
+PARAM_DEFINE_FLOAT(MT_AD_LP, 0.5f);
 
 /**
  * P gain for the airspeed control
@@ -268,7 +275,7 @@ PARAM_DEFINE_FLOAT(MT_ACC_D, 0.0f);
  *
  * @group mTECS
  */
-PARAM_DEFINE_FLOAT(MT_ACC_D_LP, 1.0f);
+PARAM_DEFINE_FLOAT(MT_ACC_D_LP, 0.5f);
 
 /**
  * Minimal acceleration (air)
@@ -286,13 +293,6 @@ PARAM_DEFINE_FLOAT(MT_ACC_MIN, -40.0f);
  */
 PARAM_DEFINE_FLOAT(MT_ACC_MAX, 40.0f);
 
-/**
- * Airspeed derivative calculation lowpass
- *
- * @group mTECS
- */
-PARAM_DEFINE_FLOAT(MT_AD_LP, 1.0f);
-
 /**
  * Minimal throttle during takeoff
  *