Line tracker

The KY-033 line tracking sensor module helps your robot follow a black line on a light-colored surface. This tutorial will guide you through connecting and using the KY-033 with Arduino to build a simple line following robot.

Specs

• Working Voltage: DC 3.3V-5V
• Working Current: ≥ 20mA
• Operating Temperature: -10°C to +50°C
• Detection Distance: 2-40cm
• Output Signal: TTL level (low level when there is an obstacle, high when there is no obstacle)
• Adjustment: The module has a multi-turn resistance knob to adjust sensitivity.
• Effective Angle: 35°
  .

#define sensor 4                                                            //define a const. variable named "sensor" with value 4, this value refers to D4 pin.
#define led 13                                                               //define a const. variable named "led" with value 2, this value refers to D13 pin.
int sensorReading;                                                          //create an integer variable named "sensorReading" to hold the sensor reading value inside.

void setup() {

    pinMode(sensor, INPUT);                                                 //set the sensor pin as an INPUT pin.
    pinMode(led, OUTPUT);                                                   //set the led pin as an OUTPUT pin.
    Serial.begin(9600);                                                     //start the hardware serial communication.
}

void loop() {

  sensorReading = digitalRead(sensor);                                      //save the sensor reading value inside the "sensorReading" variable.
  Serial.print("Line Color Is   ");                                         //print "Line Color Is  " on the Serial Monitor for easu debugging.
  
  if(sensorReading == LOW){                                                //if there is a black line turn on the led, and print "BLACK" on the serial monitor.
    digitalWrite(led, LOW);
    Serial.println("WHITE");
  }
  else{                                                                     //if there is a white line turn off the led, and print "WHITE" on the serial monitor.
    digitalWrite(led, HIGH);
    Serial.println("BLACK");
  }
}

#define enA 6//Enable1 L298 Pin enA
#define in1 5 //Motor1 L298 Pin in1
#define in2 4 //Motor1 L298 Pin in1
#define in3 3 //Motor2 L298 Pin in1
#define in4 2 //Motor2 L298 Pin in1
#define enB 9 //Enable2 L298 Pin enB

#define R_S A4 //ir sensor Right
#define L_S A5 //ir sensor Left

void setup(){ // put your setup code here, to run once

pinMode(R_S, INPUT); // declare if sensor as input
pinMode(L_S, INPUT); // declare ir sensor as input

pinMode(enA, OUTPUT); // declare as output for L298 Pin enA
pinMode(in1, OUTPUT); // declare as output for L298 Pin in1
pinMode(in2, OUTPUT); // declare as output for L298 Pin in2
pinMode(in3, OUTPUT); // declare as output for L298 Pin in3
pinMode(in4, OUTPUT); // declare as output for L298 Pin in4
pinMode(enB, OUTPUT); // declare as output for L298 Pin enB

analogWrite(enA, 120); // Write The Duty Cycle 0 to 255 Enable Pin A for Motor1 Speed
analogWrite(enB, 120); // Write The Duty Cycle 0 to 255 Enable Pin B for Motor2 Speed
delay(1000);
}
void loop(){
if((digitalRead(R_S) == 0)&&(digitalRead(L_S) == 0)){forword();} //if Right Sensor and Left Sensor are at White color then it will call forword function

if((digitalRead(R_S) == 1)&&(digitalRead(L_S) == 0)){

turnRight();
delay(10);
turnRight();

} //if Right Sensor is Black and Left Sensor is White then it will call turn Right function

if((digitalRead(R_S) == 0)&&(digitalRead(L_S) == 1)){
turnLeft();
delay(10);
turnLeft();

} //if Right Sensor is White and Left Sensor is Black then it will call turn Left function

if((digitalRead(R_S) == 1)&&(digitalRead(L_S) == 1)){Stop();} //if Right Sensor and Left Sensor are at Black color then it will call Stop function

}

void forword(){ //forword
digitalWrite(in1, HIGH); //Right Motor forword Pin
digitalWrite(in2, LOW); //Right Motor backword Pin
digitalWrite(in3, LOW); //Left Motor backword Pin
digitalWrite(in4, HIGH); //Left Motor forword Pin
}

void turnRight(){ //turnRight
digitalWrite(in1, LOW); //Right Motor forword Pin
digitalWrite(in2, HIGH); //Right Motor backword Pin
digitalWrite(in3, LOW); //Left Motor backword Pin
digitalWrite(in4, HIGH); //Left Motor forword Pin
}

void turnLeft(){ //turnLeft
digitalWrite(in1, HIGH); //Right Motor forword Pin
digitalWrite(in2, LOW); //Right Motor backword Pin
digitalWrite(in3, HIGH); //Left Motor backword Pin
digitalWrite(in4, LOW); //Left Motor forword Pin
}

void Stop(){ //stop
digitalWrite(in1, LOW); //Right Motor forword Pin
digitalWrite(in2, LOW); //Right Motor backword Pin
digitalWrite(in3, LOW); //Left Motor backword Pin
digitalWrite(in4, LOW); //Left Motor forword Pin
}