bizhang_-obav/src/modules/navigator/follow_target.h

/***************************************************************************
 *
 *   Copyright (c) 2016 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 followme.cpp
 *
 * Helper class to track and follow a given position
 *
 * @author Jimmy Johnson <catch22@fastmail.net>
 */

#pragma once

#include <controllib/blocks.hpp>
#include <controllib/block/BlockParam.hpp>
#include <lib/mathlib/math/Vector.hpp>
#include <lib/mathlib/math/Matrix.hpp>
#include "navigator_mode.h"
#include "mission_block.h"

class FollowTarget : public MissionBlock
{

public:
	FollowTarget(Navigator *navigator, const char *name);
	~FollowTarget();

	void on_inactive() override;
	void on_activation() override;
	void on_active() override;

private:

	static constexpr int TARGET_TIMEOUT_MS = 2500;
	static constexpr int TARGET_ACCEPTANCE_RADIUS_M = 5;
	static constexpr int INTERPOLATION_PNTS = 20;
	static constexpr float FF_K = .25F;
	static constexpr float OFFSET_M = 8;

	enum FollowTargetState {
		TRACK_POSITION,
		TRACK_VELOCITY,
		SET_WAIT_FOR_TARGET_POSITION,
		WAIT_FOR_TARGET_POSITION
	};

	enum {
		FOLLOW_FROM_RIGHT,
		FOLLOW_FROM_BEHIND,
		FOLLOW_FROM_FRONT,
		FOLLOW_FROM_LEFT
	};

	float _follow_position_matricies[4][9] = {
				 	 	 	 	 	 {1.0F,  -1.0F, 0.0F,
						 	 	 	  1.0F,   1.0F, 0.0F,
									  0.0F,   0.0F, 1.0F}, // follow right

									 {-1.0F,  0.0F, 0.0F,
						 	 	 	   0.0F, -1.0F, 0.0F,
									   0.0F,  0.0F, 1.0F}, // follow behind

									 {1.0F,   0.0F, 0.0F,
							 	 	  0.0F,   1.0F, 0.0F,
									  0.0F,   0.0F, 1.0F}, // follow front

									 {1.0F,   1.0F, 0.0F,
							 	 	 -1.0F,   1.0F, 0.0F,
									  0.0F,   0.0F, 1.0F}}; // follow left side


	Navigator *_navigator;
	control::BlockParamFloat	_param_min_alt;
	control::BlockParamFloat 	_param_tracking_dist;
	control::BlockParamInt 		_param_tracking_side;
	control::BlockParamFloat 	_param_tracking_resp;
	control::BlockParamFloat 	_param_yaw_auto_max;


	FollowTargetState _follow_target_state;
	int _follow_target_position;

	int _follow_target_sub;
	float _step_time_in_ms;
	float _follow_offset;

	uint64_t _target_updates;
	uint64_t _last_update_time;

	math::Vector<3> _current_vel;
	math::Vector<3> _step_vel;
	math::Vector<3> _est_target_vel;
	math::Vector<3> _target_distance;
	math::Vector<3> _target_position_offset;
	math::Vector<3> _target_position_delta;
	math::Vector<3> _filtered_target_position_delta;

	follow_target_s _current_target_motion;
	follow_target_s _previous_target_motion;
	float _avg_cos_ratio;
	double _filtered_target_lat;
	double _filtered_target_lon;
	float _yaw_rate;
	float _responsiveness;
	float _yaw_auto_max;
	float _yaw_angle;

	// Mavlink defined motion reporting capabilities

    enum {
        POS = 0,
        VEL = 1,
        ACCEL = 2,
        ATT_RATES = 3
    };

	math::Matrix<3,3> _rot_matrix;
	void track_target_position();
	void track_target_velocity();
	bool target_velocity_valid();
	bool target_position_valid();
	void reset_target_validity();
	void update_position_sp(bool velocity_valid, bool position_valid, float yaw_rate);
	void update_target_motion();
	void update_target_velocity();
};