File content as of revision 0:1a0321f1ffbc:

/*
 * TaskMoveTo.cpp
 * Copyright (c) 2018, ZHAW
 * All rights reserved.
 */

#include <cmath>
#include "TaskMoveTo.h"

using namespace std;

const float TaskMoveTo::DEFAULT_VELOCITY = 0.2f;    // default velocity value, given in [m/s]
const float TaskMoveTo::DEFAULT_ZONE = 0.01f;       // default zone value, given in [m]
const float TaskMoveTo::PI = 3.14159265f;           // the constant PI
const float TaskMoveTo::K1 = 2.0f;                  // position controller gain parameter
const float TaskMoveTo::K2 = 0.5f;                  // position controller gain parameter
const float TaskMoveTo::K3 = 0.5f;                  // position controller gain parameter

/**
 * Creates a task object that moves the robot to a given pose.
 * @param conroller a reference to the controller object of the robot.
 * @param x the x coordinate of the target position, given in [m].
 * @param y the y coordinate of the target position, given in [m].
 * @param alpha the target orientation, given in [rad].
 */
TaskMoveTo::TaskMoveTo(Controller& controller, float x, float y, float alpha) : controller(controller) {
    
    this->x = x;
    this->y = y;
    this->alpha = alpha;
    this->velocity = DEFAULT_VELOCITY;
    this->zone = DEFAULT_ZONE;
}

/**
 * Creates a task object that moves the robot to a given pose.
 * @param conroller a reference to the controller object of the robot.
 * @param x the x coordinate of the target position, given in [m].
 * @param y the y coordinate of the target position, given in [m].
 * @param alpha the target orientation, given in [rad].
 * @param velocity the maximum translational velocity, given in [m/s].
 */
TaskMoveTo::TaskMoveTo(Controller& controller, float x, float y, float alpha, float velocity) : controller(controller) {
    
    this->x = x;
    this->y = y;
    this->alpha = alpha;
    this->velocity = velocity;
    this->zone = DEFAULT_ZONE;
}

/**
 * Creates a task object that moves the robot to a given pose.
 * @param conroller a reference to the controller object of the robot.
 * @param x the x coordinate of the target position, given in [m].
 * @param y the y coordinate of the target position, given in [m].
 * @param alpha the target orientation, given in [rad].
 * @param velocity the maximum translational velocity, given in [m/s].
 * @param zone the zone threshold around the target position, given in [m].
 */
TaskMoveTo::TaskMoveTo(Controller& controller, float x, float y, float alpha, float velocity, float zone) : controller(controller) {
    
    this->x = x;
    this->y = y;
    this->alpha = alpha;
    this->velocity = velocity;
    this->zone = zone;
}

/**
 * Deletes the task object.
 */
TaskMoveTo::~TaskMoveTo() {}

/**
 * This method is called periodically by a task sequencer.
 * @param period the period of the task sequencer, given in [s].
 * @return the status of this task, i.e. RUNNING or DONE.
 */
int TaskMoveTo::run(float period) {
    
    float translationalVelocity = 0.0f;
    float rotationalVelocity = 0.0f;
    
    float x = controller.getX();
    float y = controller.getY();
    float alpha = controller.getAlpha();
    
    float rho = sqrt((this->x-x)*(this->x-x)+(this->y-y)*(this->y-y));
    
    if (rho > 0.001f) {
        
        float gamma = atan2(this->y-y, this->x-x)-alpha;
        
        while (gamma < -PI) gamma += 2.0f*PI;
        while (gamma > PI) gamma -= 2.0f*PI;
        
        float delta = gamma+alpha-this->alpha;
        
        while (delta < -PI) delta += 2.0f*PI;
        while (delta > PI) delta -= 2.0f*PI;
        
        translationalVelocity = K1*rho*cos(gamma);
        translationalVelocity = (translationalVelocity > velocity) ? velocity : (translationalVelocity < -velocity) ? -velocity : translationalVelocity;
        rotationalVelocity = (fabs(gamma) > 0.001f) ? K2*gamma+K1*sin(gamma)*cos(gamma)*(gamma+K3*delta)/gamma : 0.0f;
    }
    
    controller.setTranslationalVelocity(translationalVelocity);
    controller.setRotationalVelocity(rotationalVelocity);
    
    return (rho < zone) ? DONE : RUNNING;
}