Mapping for TP2

Dependencies:   ISR_Mini-explorer mbed

Fork of GoToPointWithAngle by Georgios Tsamis

main.cpp

Committer:
AurelienBernier
Date:
2017-03-24
Revision:
6:afde4b08166b
Parent:
5:dea05b8f30d0
Child:
7:c94070f9af78

File content as of revision 6:afde4b08166b:

#include "mbed.h"
#include "robot.h" // Initializes the robot. This include should be used in all main.cpp!
#include "math.h"
 
Timer t;

float dist(float robot_x, float robot_y, float target_x, float target_y);

//Timeout time;
int main(){
    initRobot(); //Initializing the robot
    pc.baud(9600); // baud for the pc communication

    //Target example x,y values
    float target_x=46.8, target_y=78.6, target_angle=0;

    float alpha; //angle error
    float rho; //distance from target
    float beta;
    //float k_linear=10, k_angular=200;
    float kRho=12, ka=25, kb=-15;
    float linear, angular, angular_left, angular_right;
    float dt=0.5;
    float temp;
    float d2;

    //Diameter of a wheel and distance between the 2
    float r=3.25, b=7.2;

    int speed=999; // Max speed at beggining of movement

    //Resetting coordinates before moving
    theta=0; 
    X=0;
    Y=0;

    alpha = atan2((target_y-Y),(target_x-X))-theta;
    alpha = atan(sin(alpha)/cos(alpha));
    rho = dist(X, Y, target_x, target_y);
    
    beta = -alpha-theta+target_angle;
    //beta = atan(sin(beta)/cos(beta));
    
    do {
        pc.printf("\n\n\r entered while");
        
        //Timer stuff
        dt = t.read();
        t.reset();
        t.start();
        
        //Updating X,Y and theta with the odometry values
        Odometria();
        
        alpha = atan2((target_y-Y),(target_x-X))-theta;
        alpha = atan(sin(alpha)/cos(alpha));
        rho = dist(X, Y, target_x, target_y);
        d2 = rho;
        //beta = -alpha-theta;
        beta = -alpha-theta+target_angle;
        //beta = atan(sin(beta)/cos(beta));
        
        
        //Computing angle error and distance towards the target value
        rho += dt*(-kRho*cos(alpha)*rho);
        temp = alpha;
        alpha += dt*(kRho*sin(alpha)-ka*alpha-kb*beta);
        beta += dt*(-kRho*sin(temp));
        pc.printf("\n\r d2=%f", d2);
        pc.printf("\n\r dt=%f", dt);

        //Computing linear and angular velocities
        if(alpha>=-1.5708 && alpha<=1.5708){
            linear=kRho*rho;
            angular=ka*alpha+kb*beta;
        }
        else{
            linear=-kRho*rho;
            angular=-ka*alpha-kb*beta;
        }
        angular_left=(linear-0.5*b*angular)/r;
        angular_right=(linear+0.5*b*angular)/r;

        //Slowing down at the end for more precision
        if (d2<25) {
            speed = d2*30;
        }
        
        //Normalize speed for motors
        if(angular_left>angular_right) {
            angular_right=speed*angular_right/angular_left;
            angular_left=speed;
        } else {
            angular_left=speed*angular_left/angular_right;
            angular_right=speed;
        }

        pc.printf("\n\r X=%f", X);
        pc.printf("\n\r Y=%f", Y);

        //Updating motor velocities
        leftMotor(1,angular_left);
        rightMotor(1,angular_right);

        wait(0.5);
        //Timer stuff
        t.stop();
    } while(d2>2);

    //Stop at the end
    leftMotor(1,0);
    rightMotor(1,0);

    pc.printf("\n\r %f -- arrived!", rho);
}

//Distance computation function
float dist(float robot_x, float robot_y, float target_x, float target_y){
    return sqrt(pow(target_y-robot_y,2) + pow(target_x-robot_x,2));
}