Project 15:  Arduino Line Follower Robot

Main Ideas:

Arduino Liner follower Robot, in this project we have used the 4CH Channel Infrared Tracing Module which designed based on LM339 IC.  LM339 is used in applications where a comparison between two voltage signals is required.  The 4CH Channel Infrared can read black line and it will return HIGH signal on that channel which facing the black line, if the channel face white color or nonblack color it will return Low signal , by this we can have 4 channels to help us to define if the robot still on the black line or get shifted. Once the robot start to shift from the black line we can make robot turn left or right to bring him back to run on the black line and if the robot diverted far from black line and get white color (Low signal) for all the 4 Channels, then we will make robot move back to give him a chance to return under the black line.

 
We have used the L298N H-bridge to control the two DC motors and based on this module we have developed the codes which used to make the robot move forward, turn left , turn right , move back or stop.
 
Based 4CH Channel Infrared Tracing Module we have developed the code which will read the channel inputs and based on that define how the robot will move forward, turn left , turn right , move back or stop.

Circuit

• L298 Dual Motor Driver
• 2 DC motors
• Arduino UNO
• 4CH Channel Infrared Tracing Module
• Two 9 Volt battery to provide power to L298 & Arduino.

Code

/*  https://arduino4everyones.blogspot.com/ Project 15:  Arduino Line Follower Robot */   //Uno PWM pins 3, 5, 6, 9, 10, and 11   //New Motors Pins //Motor  A Right Side on side of 3 & 4 Sensor #define enA 5 //PWM Orang  enable A #define in4 3 //Yellow IN4 #define in3 4 //Green IN3   //Motor  B Left Side on side of 1 & 2 Sensor #define enB 6 //PWM Gray Enable B #define in1 7 // blue IN2 #define in2 8 // maron IN1   int speedMotorA; // control the speed of New motor -right side int speedMotorB;// control the speed of New motor -left side   float timeToMoveBack5CM = 300; float timeToTrunBack360 = 1750;   #define Sensor1Pin 9 #define Sensor2Pin 10 #define Sensor3Pin 11 #define Sensor4Pin 12       int Sensor1 = 0; int Sensor2 = 0; int Sensor3 = 0; int Sensor4 = 0;   void setup() {   // initialize serial communication at 9600 bits per second:   Serial.begin(9600);   // Serial.println("start");   // put your setup code here, to run once:         //Set Motor A left side pins as output so we can contol the motor   pinMode(enB, OUTPUT);   pinMode(in1, OUTPUT);   pinMode(in2, OUTPUT);     //Motor B New right side pins as output so we can contol the motor   pinMode(enA, OUTPUT);   pinMode(in3, OUTPUT);   pinMode(in4, OUTPUT);     //set initial speed for the motors   speedMotorA = 190; // control the speed of motor -left side   speedMotorB = 190; // control the speed of motor -right side     pinMode (Sensor1Pin, INPUT);   pinMode (Sensor2Pin, INPUT);   pinMode (Sensor3Pin, INPUT);   pinMode (Sensor4Pin, INPUT);   // TunBackword360();   // stopmove(); }   void loop() {   // put your main code here, to run repeatedly:   //MoveLogic();   //moveForward();   //moveBackword5CM();   //TrunRight5CM();   //moveForwardone();   //moveForwardReduceSpeed();   //moveForward();   // read_sensors();   //TrunLefteduceSpeed();   //TrunRighteduceSpeed();   //TunBackword360();   moveLogic(); }   void moveLogic() {   read_sensors();   //Read the Sensor if HIGH (BLACK Line) or LOW (WHITE Line)   if (Sensor4 == LOW && Sensor3 == LOW && Sensor2 == LOW && Sensor1 == LOW)   {     stopmove();     moveBackword5CM();     Serial.println("stopmove :");   }   //Read the Sensor if HIGH (BLACK Line) or LOW (WHITE Line)   if (Sensor4 == HIGH && Sensor3 == HIGH && Sensor2 == HIGH && Sensor1 == HIGH)   {        TunBackword360();     stopmove();     Serial.println("stopmove :");   }     if (Sensor4 == LOW && Sensor3 == HIGH && Sensor2 == HIGH && Sensor1 == LOW)   {     moveForwardReduceSpeed();     Serial.println("moveForwardReduceSpeed :");   }     //trun Left   //Read the Sensor if HIGH (BLACK Line) or LOW (WHITE Line)   if (Sensor4 == HIGH && Sensor3 == LOW && Sensor2 == LOW && Sensor1 == LOW)   {     TrunLefteduceSpeed();     Serial.println("TrunLefteduceSpeed :");   }   if (Sensor4 == HIGH && Sensor3 == HIGH && Sensor2 == LOW && Sensor1 == LOW)   {     //TrunLefteduceSpeed();     moveForwardReduceSpeed();     Serial.println("moveForwardReduceSpeed(); :");   }     if (Sensor4 == HIGH && Sensor3 == HIGH && Sensor2 == HIGH && Sensor1 == LOW)   {     TrunLefteduceSpeed();     Serial.println("TrunLefteduceSpeed :");   }   if (Sensor4 == LOW && Sensor3 == HIGH && Sensor2 == LOW && Sensor1 == LOW)   {     //TrunLefteduceSpeed();     moveForwardReduceSpeed();     Serial.println("moveForwardReduceSpeed(); :");   }           // TrunRighteduceSpeed   if (Sensor4 == LOW && Sensor3 == HIGH && Sensor2 == HIGH && Sensor1 == HIGH)   {     TrunRighteduceSpeed();     Serial.println("TrunRighteduceSpeed :");   }   if (Sensor4 == LOW && Sensor3 == LOW && Sensor2 == HIGH && Sensor1 == HIGH)   {     // TrunRighteduceSpeed();     moveForwardReduceSpeed();     Serial.println(" moveForwardReduceSpeed(); :");   }     if (Sensor4 == LOW && Sensor3 == LOW && Sensor2 == HIGH && Sensor1 == LOW)   {     //TrunRighteduceSpeed();     moveForwardReduceSpeed();     Serial.println("moveForwardReduceSpeed(); :");   }   if (Sensor4 == LOW && Sensor3 == LOW && Sensor2 == LOW && Sensor1 == HIGH)   {     TrunRighteduceSpeed();     Serial.println("TrunRighteduceSpeed :");   }     } void read_sensors() //Read the Sensor if HIGH (BLACK Line) or LOW (WHITE Line) {   Sensor1 = digitalRead(Sensor1Pin);   Sensor2 = digitalRead(Sensor2Pin);   Sensor3 = digitalRead(Sensor3Pin);   Sensor4 = digitalRead(Sensor4Pin);     Serial.print("Sensor1Pin :");   Serial.println(Sensor1);   Serial.print("Sensor2Pin :");   Serial.println(Sensor2);   Serial.print("Sensor3Pin :");   Serial.println(Sensor3);   Serial.print("Sensor4Pin :");   Serial.println(Sensor4);     //delay(1000); }   void ResetSpeedMotors() {   speedMotorA = 220; // control the speed of motor -rigt side   speedMotorB = 220; // control the speed of motor -left side }   void ReduceSpeed() {   //set speed   speedMotorA = 120; // control the speed of motor -rigt side   speedMotorB = 120; // control the speed of motor -left side }   void moveForwardone() {   ResetSpeedMotors();   // run motor B back   //  analogWrite(enB, speedMotorB);   //   digitalWrite(in1, HIGH);   //  digitalWrite(in2, LOW);     // run motor B forward   //  analogWrite(enB, speedMotorB);   //   digitalWrite(in1, LOW);   //  digitalWrite(in2, HIGH);     // run motor A back   //  analogWrite(enA, speedMotorA);   //  digitalWrite(in3, LOW);   //  digitalWrite(in4, HIGH);     // run motor A forward   //  analogWrite(enA, speedMotorA);   //  digitalWrite(in3, HIGH);   //  digitalWrite(in4, LOW);   }     void moveBackword5CM() {     ReduceSpeed();   unsigned long moveBackStartTime = millis(); // save the time that we started moveback   while ((millis() - moveBackStartTime) < (timeToMoveBack5CM) ) // stay in this loop until timeToMoveBack10CM (1.1 seconds) has elapsed   {     // run motor A back     analogWrite(enA, speedMotorA);     digitalWrite(in3, LOW);     digitalWrite(in4, HIGH);       // run motor B back     analogWrite(enB, speedMotorB);     digitalWrite(in1, HIGH);     digitalWrite(in2, LOW);     } }   void TunBackword360() {     ResetSpeedMotors();   unsigned long moveBackStartTime = millis(); // save the time that we started moveback   while ((millis() - moveBackStartTime) < (timeToTrunBack360) ) // stay in this loop until timeToMoveBack10CM (1.1 seconds) has elapsed   {       //Motor  B Left Side on side of 1 & 2 Sensor     //forward     analogWrite(enB, speedMotorB);     digitalWrite(in1, LOW);     digitalWrite(in2, HIGH);     //Motor  A Right Side on side of 3 & 4 Sensor     //Back     analogWrite(enA, speedMotorA);     digitalWrite(in3, LOW);     digitalWrite(in4, HIGH);     }   }   void moveForward() {   ResetSpeedMotors();   //Motor  B Left Side on side of 1 & 2 Sensor   analogWrite(enB, speedMotorB);   digitalWrite(in1, LOW);   digitalWrite(in2, HIGH);   //Motor  A Right Side on side of 3 & 4 Sensor   analogWrite(enA, speedMotorA);   digitalWrite(in3, HIGH);   digitalWrite(in4, LOW); } void moveForwardReduceSpeed() {   ReduceSpeed();   //Motor  B Left Side on side of 1 & 2 Sensor   analogWrite(enB, speedMotorB);   digitalWrite(in1, LOW);   digitalWrite(in2, HIGH);   //Motor  A Right Side on side of 3 & 4 Sensor   analogWrite(enA, speedMotorA);   digitalWrite(in3, HIGH);   digitalWrite(in4, LOW); }   void TrunLefteduceSpeed() {   ReduceSpeed();   //Motor  B Left Side on side of 1 & 2 Sensor   //forward   analogWrite(enB, speedMotorB);   digitalWrite(in1, LOW);   digitalWrite(in2, HIGH);   //Motor  A Right Side on side of 3 & 4 Sensor   //Back   analogWrite(enA, speedMotorA);   digitalWrite(in3, LOW);   digitalWrite(in4, HIGH); }   void TrunRighteduceSpeed() {   ReduceSpeed();   //Motor  B Left Side on side of 1 & 2 Sensor   //back   analogWrite(enB, speedMotorB);   digitalWrite(in1, HIGH);   digitalWrite(in2, LOW);   //Motor  A Right Side on side of 3 & 4 Sensor   //forward   analogWrite(enA, speedMotorA);   digitalWrite(in3, HIGH);   digitalWrite(in4, LOW); } void stopmove() {   digitalWrite(in1, LOW);   digitalWrite(in2, LOW);   analogWrite(enB, 0);     digitalWrite(in3, LOW);   digitalWrite(in4, LOW);   analogWrite(enA, 0);     delay (100); }