Obstacle Avoiding Robot

Obstacle Avoiding Robot

An obstacle avoiding robot is an autonomous mobile robot designed to detect obstacles in its path and navigate around them without human intervention. This project introduces core robotics concepts such as distance sensing, decision-making logic, and motor control.

Required Components

• Arduino Uno

• Ultrasonic Sensor (HC-SR04)

• L298N Motor Driver Module

• DC Motors with Wheels

• Robot Chassis

• Servo Motor (optional, for sensor scanning)

• Battery Pack

• Jumper Wires

• Breadboard (optional)

How It Works

The robot uses an ultrasonic sensor to continuously measure the distance between itself and any object ahead. The Arduino triggers the sensor to send ultrasonic pulses and listens for the echo reflected by obstacles.

• If no obstacle is detected within a preset distance, the robot moves forward

• If an obstacle is detected, the robot stops

• The robot then turns left or right to find a clear path

The Arduino processes the distance data and sends control signals to the motor driver to move the motors accordingly.

Circuit Connection

Ultrasonic Sensor (HC-SR04)

• VCC → 5V

• GND → GND

• TRIG → Arduino Pin 6

• ECHO → Arduino Pin 7

Motor Driver (L298N)

• IN1 → Arduino Pin 8

• IN2 → Arduino Pin 9

• IN3 → Arduino Pin 10

• IN4 → Arduino Pin 11

• ENA & ENB → Jumper Enabled or PWM Pins

• Motor terminals → DC Motors

• Power input → External Battery

Application Areas

• Autonomous Robotics

• Smart Navigation Systems

• Educational Robotics Projects

• Research and Prototyping

This project can be enhanced by adding servo-based scanning, PID control, or wireless monitoring for smarter navigation.

Code Example

#define TRIG_PIN 6
#define ECHO_PIN 7

#define IN1 8
#define IN2 9
#define IN3 10
#define IN4 11

long duration;
int distance;

void setup() {
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);
  pinMode(IN3, OUTPUT);
  pinMode(IN4, OUTPUT);
}

void loop() {
  distance = getDistance();

  if (distance > 20) {
    moveForward();
  } else {
    stopRobot();
    delay(300);
    turnRight();
    delay(400);
  }
}

int getDistance() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  duration = pulseIn(ECHO_PIN, HIGH);
  int cm = duration * 0.034 / 2;
  return cm;
}

void moveForward() {
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
}

void turnRight() {
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, LOW);
  digitalWrite(IN4, LOW);
}

void stopRobot() {
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, LOW);
  digitalWrite(IN4, LOW);
}