PID_Robot

#include <SPI.h>
#include <SD.h>

#include <AFMotor.h>
//#include <NewPing.h>
#include "SR04.h"
#include <IRremote.h>

//SD module settings
File myFile;
const int8_t DISABLE_CHIP_SELECT = 10;

int pinCS = 53; // Pin komunikacji z karta SD

//Sensors settings
int LEFT_SENSOR_TRIG = A2;
int LEFT_SENSOR_ECHO = A3;
int FRONT_SENSOR_TRIG = A0;
int FRONT_SENSOR_ECHO = A1;

SR04 sr04_left = SR04(LEFT_SENSOR_ECHO, LEFT_SENSOR_TRIG);
SR04 sr04_front = SR04(FRONT_SENSOR_ECHO, FRONT_SENSOR_TRIG);

//Remote controll settings
int RECV_PIN = 40;

IRrecv irrecv(RECV_PIN);
decode_results results;

//DC motors settings
AF_DCMotor motor1(1, MOTOR12_1KHZ);
AF_DCMotor motor2(3, MOTOR34_1KHZ);

int NO_OBSTACLE = 0;
int OBSTACLE = 1;

//PID
const float Kp_wall = 20;
const float Ki_wall = 0.003;
const float Kd_wall = 9;

const float Kp_front = 30;
const float Ki_front = 0;
const float Kd_front = 15;

const int offset = 12; // target distance
const int max_front_distance = 16; // max front distanc

int Tp = 128; // target power

float error_wall = 0;
float lastError_wall = 0;
int correction_wall = 0;
float p_wall = 0;
float i_wall = 0;
float d_wall = 0;

int Wall = 0;
int Front = 0;

float error_front = 0;
float lastError_front = 0;
float correction_front = 0;
float p_front = 0;
float i_front = 0;
float d_front = 0;

int leftMotorSpeed = 0;
int rightMotorSpeed = 0;

int front_status = 0;

//int rangeFrontObstacle = 0;
//int rangeWallObstacle = 0;
//int rangeFront = 0;
//int rangeWall = 0;
//int speedSet = 0;

//0 - true; 1 - false
int rightTurnBegin = 0;
int leftTurnBegin = 0;
int straightLineBegin = 0;

int speedSet = 0;



void setup() {
  pinMode(RECV_PIN, INPUT);
  irrecv.enableIRIn();

  Serial.begin(9600);
  pinMode(pinCS, OUTPUT);
  delay(5000);

  if (SD.begin())
  {
    Serial.println("SD card is ready to use.");
  } else
  {
    Serial.println("SD card initialization failed");
    return;
  }

}

void loop() {

beginning:

  myFile = SD.open("DaneMapy.txt", FILE_WRITE);

  if (irrecv.decode(&results))
  {
    switch (results.value)
    {
      case 0xFF22DD: //vol-
        Serial.print("falling back");
        fall_back();
        break;

      case 0xFF02FD: //vol+
        drive_forward();
        break;

      case 0xFFC23D: //play/pause
        motor_stop();
        break;
    }
    irrecv.resume();
  }
  //checks if there is obstacle in front
  front_status = GET_FRONT_STATUS();

  if (front_status == OBSTACLE) {

    if (leftTurnBegin == 0) {
      zero_wall();
    }
    followWall_front();

	//changing turn flag until next obstacle
    rightTurnBegin = 1;
    straightLineBegin = 0;

    goto beginning;
  }

  followWall();
}

void followWall() {

//When robot drives straight (until there is no obstacle) changing flag to true

  rightTurnBegin = 0;

  Wall = sr04_left.Distance();
  error_wall = Wall - offset;
  i_wall = (i_wall + error_wall);
  d_wall = (error_wall - lastError_wall);

  correction_wall = Kp_wall * error_wall + Ki_wall * i_wall + Kd_wall * d_wall;


//if error is less then 10, it means that the robot follow the wall correctly
  if (error_wall < 10) {

    if (straightLineBegin == 0) {
      zero_wall();
    }

    if (correction_wall > 127 && correction_wall > 0) {
      correction_wall = 127;
    }

    if (correction_wall < -127 && correction_wall < 0) {
      correction_wall = -127;
    }

    rightMotorSpeed  = Tp + correction_wall;
    leftMotorSpeed = Tp - correction_wall;


    leftTurnBegin = 0;
    straightLineBegin = 1;
  } else {

	//if error if greater then 10, robot has to turn right

    if (leftTurnBegin == 0) {
      zero_wall();
      zero_front();
    }

    //PID left turn
    int speed = 2.5 * error_wall + 8 * d_wall;

    if (speed > 127 && speed > 0) {
      speed = 127;
    }

    if (speed < -127 && speed < 0) {
      speed = -127;
    }

    rightMotorSpeed  = Tp + (speed);
    leftMotorSpeed = Tp - (speed);

    leftTurnBegin = 1;
    straightLineBegin = 0;
  }

  motor1.setSpeed(rightMotorSpeed);
  motor1.run(FORWARD);
  motor2.setSpeed(leftMotorSpeed);
  motor2.run(FORWARD);

  lastError_wall = error_wall;
  zero_front();
}

void zero_wall(void) {
  i_wall = 0;
  d_wall = 0;
  lastError_wall = 0;
}

void zero_front(void) {
  i_front = 0;
  d_front = 0;
  lastError_front = 0;
}

void followWall_front()
{

  Front = sr04_front.Distance();
  error_front = (Front - max_front_distance);
  i_front = (i_front + error_front);
  d_front = (error_front - lastError_front);

  correction_front = Kp_front * error_front + Ki_front * i_front + Kd_front * d_front;


  if (correction_front > 127 && correction_front > 0) {
    correction_front = 127;
  }

  if (correction_front < -127 && correction_front < 0) {
    correction_front = -127;
  }

  rightMotorSpeed  = Tp + correction_front;
  leftMotorSpeed = Tp - correction_front;

  motor1.setSpeed(rightMotorSpeed);
  motor1.run(FORWARD);
  motor2.setSpeed(leftMotorSpeed);
  motor2.run(FORWARD);

  lastError_front = error_front;
}

void drive_forward() {
  motor1.setSpeed(128);
  motor2.setSpeed(128);
  motor1.run(FORWARD);
  motor2.run(FORWARD);
  delay(400);
}
//zatrzymuje robota na 5 sekund
void motor_stop() {
  motor1.run(RELEASE);
  motor2.run(RELEASE);
  delay(5000);
}

//wycofanie gdy robot wjedzie w przeszkode
void fall_back() {
  motor1.setSpeed(128);
  motor2.setSpeed(128);
  motor1.run(BACKWARD);
  motor2.run(BACKWARD);
  delay(500);
  motor1.run(BACKWARD);
  motor2.run(FORWARD);
  delay(400);
  Serial.print("falling back");
  Serial.println();
}


int GET_LEFT_STATUS(void) {
  if (sr04_left.Distance() < offset)
    return OBSTACLE;
  else
    return NO_OBSTACLE;
}

int GET_FRONT_STATUS(void) {
  if (sr04_front.Distance() < max_front_distance)
    return OBSTACLE;
  else
    return NO_OBSTACLE;
}