ManualSmoothing in xy

src/lib/FlightTasks/CMakeLists.txt

@@ -41,6 +41,7 @@ px4_add_module(
 		tasks/FlightTaskManualAltitudeSmooth.cpp
 		tasks/FlightTaskManualPosition.cpp
 		tasks/Utility/ManualSmoothingZ.cpp
+		tasks/Utility/ManualSmoothingXY.cpp
 		SubscriptionArray.cpp
 		FlightTasks.cpp
 	DEPENDS

src/lib/FlightTasks/tasks/Utility/ManualSmoothingXY.cpp

@@ -0,0 +1,241 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file ManualSmoothingXY.cpp
+ */
+
+#include "ManualSmoothingXY.hpp"
+#include "uORB/topics/parameter_update.h"
+#include <mathlib/mathlib.h>
+#include <float.h>
+
+ManualSmoothingXY::ManualSmoothingXY(const matrix::Vector2f &vel) :
+	_vel(vel), _vel_sp_prev(vel)
+{
+	_acc_hover_h = param_find("MPC_ACC_HOR_MAX");
+	_acc_xy_max_h = param_find("MPC_ACC_HOR");
+	_dec_xy_min_h = param_find("DEC_HOR_SLOW");
+	_jerk_max_h = param_find("MPC_JERK_MAX");
+	_jerk_min_h = param_find("MPC_JERK_MIN");
+	_vel_manual_h = param_find("MPC_VEL_MANUAL");
+
+	/* Load the params the very first time */
+	_setParams();
+}
+
+void
+ManualSmoothingXY::smoothVelFromSticks(matrix::Vector2f &vel_sp, const matrix::Vector2f &vel, const float dt)
+{
+	_updateParams();
+
+	_updateAcceleration(vel_sp, vel, dt);
+
+	_velocitySlewRate(vel_sp, dt);
+}
+
+void
+ManualSmoothingXY::_updateParams()
+{
+	bool updated;
+	parameter_update_s param_update;
+	orb_check(_parameter_sub, &updated);
+
+	if (updated) {
+		orb_copy(ORB_ID(parameter_update), _parameter_sub, &param_update);
+		_setParams();
+	}
+}
+
+void
+ManualSmoothingXY::_setParams()
+{
+	param_get(_acc_hover_h, &_acc_hover);
+	param_get(_acc_xy_max_h, &_acc_xy_max);
+	param_get(_dec_xy_min_h, &_dec_xy_min);
+	param_get(_jerk_max_h, &_jerk_max);
+	param_get(_jerk_min_h, &_jerk_min);
+	param_get(_vel_manual_h, &_vel_manual);
+}
+
+void
+ManualSmoothingXY::_updateAcceleration(matrix::Vector2f &vel_sp, const matrix::Vector2f &vel, const float dt)
+{
+	/*
+	 * In manual mode we consider four states with different acceleration handling:
+	 * 1. user wants to stop
+	 * 2. user wants to quickly change direction
+	 * 3. user wants to accelerate
+	 * 4. user wants to decelerate
+	 */
+	Intention intention = _getIntention(vel_sp);
+
+	/* Adapt acceleration and jerk based on current state and
+	 * intention. Jerk is only used for braking.
+	 */
+	_getStateAcceleration(vel_sp, vel, intention, dt);
+
+	/* Smooth velocity setpoint based on acceleration */
+	_velocitySlewRate(vel_sp, dt);
+}
+
+ManualSmoothingXY::Intention
+ManualSmoothingXY::_getIntention(const matrix::Vector2f &vel_sp)
+{
+	if (vel_sp.length() > FLT_EPSILON) {
+		/* Distinguish between acceleration, deceleration and direction change */
+
+		/* Check if stick direction and current velocity are within 120.
+		 * If previous and current setpoint are more than 120 apart, we assume
+		 * that the user demanded a direction change. */
+		matrix::Vector2f vel_sp_unit = vel_sp;;
+		matrix::Vector2f vel_sp_prev_unit = _vel_sp_prev;
+
+		if (vel_sp.length() > FLT_EPSILON) {
+			vel_sp_unit.normalize();
+		}
+
+		if (_vel_sp_prev.length() > FLT_EPSILON) {
+			vel_sp_prev_unit.normalize();
+		}
+
+		const bool is_aligned = (vel_sp_unit * vel_sp_prev_unit) > -0.5f;
+
+		/* Check if user wants to accelerate */
+		bool do_acceleration = _vel_sp_prev.length() < FLT_EPSILON; // Because current is not zero but previous sp was zero
+		do_acceleration = do_acceleration || (is_aligned
+						      && (vel_sp.length() >= _vel_sp_prev.length() - 0.01f)); //User demands larger or same speed
+
+		if (do_acceleration) {
+			return Intention::acceleration;
+
+		} else if (!is_aligned) {
+			return Intention::direction_change;
+
+		} else {
+			return Intention::deceleration;
+		}
+	}
+
+	return Intention::brake; //default is brake
+}
+
+void
+ManualSmoothingXY::_getStateAcceleration(const matrix::Vector2f &vel_sp, const matrix::Vector2f &vel,
+		const Intention &intention, const float dt)
+{
+
+	switch (intention) {
+	case Intention::brake: {
+
+			/* First iteration where user demands brake */
+			if (intention != intention) {
+				/* we start braking with lowest acceleration
+				 * This make stopping smoother. */
+				_acc_state_dependent = _dec_xy_min;
+
+				/* Adjust jerk based on current velocity, This ensures
+				 * that the vehicle will stop much quicker at large speed but
+				 * very slow at low speed.
+				 */
+				_jerk_state_dependent = _jerk_max; // default
+
+				if (_jerk_max > _jerk_min) {
+
+					_jerk_state_dependent = (_jerk_max - _jerk_min)
+								/ _vel_manual * vel.length() + _jerk_min;
+				}
+
+				/* Since user wants to brake smoothly but NOT continuing to fly
+				 * in the opposite direction, we have to reset the slewrate
+				 * by setting previous velocity setpoint to current velocity. */
+				_vel_sp_prev = vel;
+			}
+
+			/* limit jerk when braking to zero */
+			float jerk = (_acc_hover - _acc_state_dependent) / dt;
+
+			if (jerk > _jerk_state_dependent) {
+				_acc_state_dependent = _jerk_state_dependent * dt
+						       + _acc_state_dependent;
+
+			} else {
+				_acc_state_dependent = _acc_hover;
+			}
+
+			break;
+		}
+
+	case Intention::direction_change: {
+
+			/* We allow for fast change by setting previous setpoint to current
+			 * setpoint.
+			 */
+			_vel_sp_prev = vel_sp;
+
+			/* Because previous setpoint is equal to current setpoint,
+			 * slewrate will have no effect. Nonetheless, just set
+			 * acceleration to maximum.
+			 */
+			_acc_state_dependent = _acc_xy_max;
+
+			break;
+		}
+
+	case Intention::acceleration: {
+			/* Limit acceleration linearly based on velocity setpoint.*/
+			_acc_state_dependent = (_acc_xy_max - _dec_xy_min)
+					       / _vel_manual * vel_sp.length() + _dec_xy_min;
+			break;
+		}
+
+	case Intention::deceleration: {
+			_acc_state_dependent = _dec_xy_min;
+			break;
+		}
+	}
+
+	/* Update intention for next iteration */
+	_intention = intention;
+}
+
+void
+ManualSmoothingXY::_velocitySlewRate(matrix::Vector2f &vel_sp, const float dt)
+{
+	/* Adjust velocity setpoint if demand exceeds acceleration. */
+	matrix::Vector2f acc = (vel_sp - _vel_sp_prev) / dt;
+
+	if (acc.length() > _acc_state_dependent) {
+		vel_sp = acc.normalized() * _acc_state_dependent  * dt + _vel_sp_prev;
+	}
+}

src/lib/FlightTasks/tasks/Utility/ManualSmoothingXY.hpp

@@ -0,0 +1,117 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file SmoothingXY.hpp
+ *
+ * This Class is used for smoothing the velocity setpoints in Z-direction.
+ */
+
+#pragma once
+
+#include <systemlib/param/param.h>
+#include <matrix/matrix/math.hpp>
+
+class ManualSmoothingXY
+{
+public:
+	ManualSmoothingXY(const matrix::Vector2f &vel);
+	~ManualSmoothingXY() {};
+
+	/* Smoothing of velocity setpoint horizontally based
+	 * on flight direction.
+	 * @param vel_sp: velocity setpoint in xy
+	 * @param dt: time delta in seconds
+	 */
+	void smoothVelFromSticks(matrix::Vector2f &vel_sp, const matrix::Vector2f &vel, const float dt);
+
+	/* User intention: brake or acceleration */
+	enum class Intention {
+		brake,
+		acceleration,
+		deceleration,
+		direction_change
+	};
+
+	/* Getter methods */
+	//float getMaxAcceleration();
+	Intention getIntention() {return _intention;};
+
+	/* Overwrite methods:
+	 * Needed if different parameter values than default required.
+	 */
+	void overwriteHoverAcceleration(float acc) {_acc_hover = acc;};
+	void overwriteMaxAcceleration(float acc) {_acc_xy_max = acc;};
+	void overwriteDecelerationMin(float dec) {_dec_xy_min = dec;};
+	void overwriteJerkMax(float jerk) {_jerk_max = jerk;};
+	void overwriteJerkMin(float jerk) {_jerk_min = jerk;};
+
+private:
+
+	/* User intention: brake or acceleration */
+	Intention _intention{Intention::acceleration};
+
+	/* Acceleration that depends on vehicle state
+	 * _acc_max_down <= _acc_state_dependent <= _acc_max_up
+	 */
+	float _acc_state_dependent{0.0f};
+	float _jerk_state_dependent{0.0f};
+
+	matrix::Vector2f _vel; // current velocity xy
+	matrix::Vector2f _vel_sp_prev; // previous velocity setpoint
+
+	/* Params */
+	param_t _acc_hover_h{PARAM_INVALID};
+	param_t _acc_xy_max_h{PARAM_INVALID};
+	param_t _dec_xy_min_h{PARAM_INVALID};
+	param_t _jerk_max_h{PARAM_INVALID};
+	param_t _jerk_min_h{PARAM_INVALID};
+	param_t _vel_manual_h{PARAM_INVALID};
+	float _acc_hover{50.0f}; // acceleration in hover
+	float _acc_xy_max{10.0f}; // acceleration in flight
+	float _dec_xy_min{1.0f}; // deceleration in flight
+	float _jerk_max{15.0f}; // jerk max during brake
+	float _jerk_min{1.0f}; // jerk min during brake
+	float _vel_manual{}; //maximum velocity in manual controlled mode
+	int _parameter_sub{-1};
+
+	/* Helper methods */
+	void _setParams();
+	void _updateParams();
+	void _updateAcceleration(matrix::Vector2f &vel_sp, const matrix::Vector2f &vel, const float dt);
+	Intention _getIntention(const matrix::Vector2f &vel_sp);
+	void _getStateAcceleration(const matrix::Vector2f &vel_sp, const matrix::Vector2f &vel, const Intention &intention,
+				   const float dt);
+	void _velocitySlewRate(matrix::Vector2f &vel_sp, const float dt);
+
+};