how to make Obstacle avoiding robot at home

Arduino automatic robot

Needed

Arduino UNO

• Mini breadboard
• L298 motor driver module
• 2x dc motors with wheels
• HC-SR04 ultrasonic sensor
• Micro servo motor
• Button
• Red LED
• 220 Ohm resistor
• 9V battery holder (with or without power jack)
• 8 spacers (male-female)
• 8 nuts and 8 screws

Make this circuit perfectly

Get the code of your arduino from here 

//Obstacle Avoiding robot

//Praveen Sridhar 

//psbots.blogspot.com

const int left=1,mid=2,right=3;

const int i1=8,i2=10,ea=9,i3=5,i4=7,eb=6;

const int cthres=600,rthres=600,lthres=600;

int s1=0;

int s2=0;

int s3=0;

int r;



void setup()

{

  Serial.begin(9600);

  pinMode(i1,OUTPUT);

  pinMode(i2,OUTPUT);

  pinMode(ea,OUTPUT);

  pinMode(13,OUTPUT);

  pinMode(i4,OUTPUT);

  pinMode(eb,OUTPUT);

}



void updateS()

{

  s1=analogRead(left);

  s2=analogRead(mid);

  s3=analogRead(right);

}



void moveforward()

{

 analogWrite(ea,200);

 analogWrite(eb,200);

 digitalWrite(i2,LOW);

 digitalWrite(i1,HIGH);

 digitalWrite(i4,LOW);

 digitalWrite(i3,HIGH); 

}



void turnleft()

{

  analogWrite(ea,150);

  analogWrite(eb,150);

  digitalWrite(i1,LOW);

  digitalWrite(i2,HIGH);

  digitalWrite(i4,LOW);

  digitalWrite(i3,HIGH);

}



void turnright()

{

  analogWrite(eb,150);

  analogWrite(ea,150);

  digitalWrite(i2,LOW);

  digitalWrite(i1,HIGH);

  digitalWrite(i3,LOW);

  digitalWrite(i4,HIGH);

}  



void loop()

{ 

  moveforward();

  

  updateS();

  

  if(s2>cthres)

  {

    randomSeed(analogRead(0));

    r=random(3000);

    if(r%2==0)

        turnright();

    else

        turnleft();

    while((s3>rthres-10||s2>cthres-10))

    {

      updateS();

      delay(10);

    }

    moveforward();

  }

  

  if((s3>rthres)||((s3>rthres)&&(s2>cthres)))

  {

    turnleft();

    while(s3>rthres-10)

    {

      updateS();

      delay(10);

    }

    moveforward();

  }

  

  if((s1>lthres)||((s1>lthres)&&(s2>cthres)))

  {

    turnright();

    while(s1>lthres-10)

    {

      updateS();

      delay(10);

    }

    moveforward();

  }

    

}



This code is depend on your pin configuration