How to Make Arduino Human Following Robot using Arduino UNO, L293D Motor Shield, Ultrasonic Sensor, IR Sensor and Servo Motor

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⚡ Project Level: Intermediate

⏱ Time Required: 1 Hour

💰 Budget: Medium

🤖 Function: Human/Object Following Robot

INTRODUCTION

Want to build a robot that follows you automatically? 🤖 In this project, you will learn how to make a Human Following Robot using Arduino UNO, Ultrasonic Sensor, IR sensors, and L293D motor shield.

This robot detects objects in front and follows them while avoiding wrong direction using IR sensors.

WATCH YOUTUBE VIDEO

COMPONENTS REQUIRED

Image	Name	Qty	Buy
	Arduino UNO	1	{getButton} $text={Buy Now} $icon={cart} $color={#007bff}
	L298N Motor Driver	1	{getButton} $text={Buy Now} $icon={cart} $color={#007bff}
	Ultrasonic Sensor	1	{getButton} $text={Buy Now} $icon={cart} $color={#007bff}
	Servo Motor	1	{getButton} $text={Buy Now} $icon={cart} $color={#007bff}
	IR Sensor Module	2	{getButton} $text={Buy Now} $icon={cart} $color={#007bff}

TOOLS REQUIRED

Image	Tool Name	Quantity	Buy
	Screwdriver	1	{getButton} $text={Buy Tool} $icon={cart} $color={#007bff}
	Wire Cutter	1	{getButton} $text={Buy Tool} $icon={cart} $color={#007bff}

APPS AND ONLINE SERVICES

Image	App Name	Access
	Arduino IDE	{getButton} $text={Download} $icon={download} $color={#007bff}

CIRCUIT DIAGRAM

WIRING CONNECTIONS

Ultrasonic Sensor

Trig	A2
Echo	A3
VCC	5V
GND	GND

IR Sensors

Right IR	A1
Left IR	A5

Servo Motor

Signal	Pin 10
VCC	5V
GND	GND

ARDUINO CODE

//Arduino Human Following Robot // You have to install the AFMotor and NewPing library Before Uploading the sketch // You can find all the required libraris from arduino library manager. // Contact me on instagram for any query(Insta Id : prateek.815) //include the library code: #include<NewPing.h> #include<Servo.h> #include<AFMotor.h> #define LEFT A5 // Right IR sensor connected to analog pin A2 of Arduino Uno: #define RIGHT A1 // Left IR sensor connected to analog pin A3 of Arduino Uno: #define TRIGGER_PIN A2 // Trigger pin connected to analog pin A1 of Arduino Uno: #define ECHO_PIN A3 // Echo pin connected to analog pin A0 of Arduino Uno: #define MAX_DISTANCE 200 // Maximum ping distance: unsigned int distance = 0; //Variable to store ultrasonic sensor distance: unsigned int Right_Value = 0; //Variable to store Right IR sensor value: unsigned int Left_Value = 0; //Variable to store Left IR sensor value: int d=10; NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); //NewPing setup of pins and maximum distance: //create motor objects AF_DCMotor Motor1(1,MOTOR12_1KHZ); AF_DCMotor Motor2(2,MOTOR12_1KHZ); AF_DCMotor Motor3(3,MOTOR34_1KHZ); AF_DCMotor Motor4(4,MOTOR34_1KHZ); Servo myservo; //create servo object to control the servo: int pos=0; //variable to store the servo position: void setup() { // the setup function runs only once when power on the board or reset the board: Serial.begin(9600); //initailize serial communication at 9600 bits per second: myservo.attach(10); // servo attached to pin 10 of Arduino UNO { for(pos = 90; pos <= 180; pos += 1){ // goes from 90 degrees to 180 degrees: myservo.write(pos); //tell servo to move according to the value of 'pos' variable: delay(15); //wait 15ms for the servo to reach the position: } for(pos = 180; pos >= 0; pos-= 1) { // goes from 180 degrees to 0 degrees: myservo.write(pos); //tell servo to move according to the value of 'pos' variable: delay(15); //wait 15ms for the servo to reach the position: } for(pos = 0; pos<=90; pos += 1) { //goes from 180 degrees to 0 degrees: myservo.write(pos); //tell servo to move according to the value of 'pos' variable: delay(15); //wait 15ms for the servo to reach the position: } } pinMode(RIGHT, INPUT); //set analog pin RIGHT as an input: pinMode(LEFT, INPUT); //set analog pin RIGHT as an input: stop(); } // the lope function runs forever void loop() { delay(50); //wait 50ms between pings: distance = sonar.ping_cm(); //send ping, get distance in cm and store it in 'distance' variable: Serial.print("distance"); Serial.println(distance); // print the distance in serial monitor: Right_Value = !digitalRead(RIGHT); // read the value from Right IR sensor: Left_Value = !digitalRead(LEFT); // read the value from Left IR sensor: Serial.print("RIGHT"); Serial.println(Right_Value); // print the right IR sensor value in serial monitor: Serial.print("LEFT"); Serial.println(Left_Value); //print the left IR sensor value in serial monitor: if((distance > 1) && (distance < d)){ //check wheather the ultrasonic sensor's value stays between 1 to 15. //If the condition is 'true' then the statement below will execute: //Move Forward: Motor1.setSpeed(130); //define motor1 speed: Motor1.run(FORWARD); //rotate motor1 clockwise: Motor2.setSpeed(130); //define motor2 speed: Motor2.run(FORWARD); //rotate motor2 clockwise: Motor3.setSpeed(130); //define motor3 speed: Motor3.run(FORWARD); //rotate motor3 clockwise: Motor4.setSpeed(130); //define motor4 speed: Motor4.run(FORWARD); //rotate motor4 clockwise: }else if((Right_Value==1) && (Left_Value==0)) { //If the condition is 'true' then the statement below will execute: //Turn right Motor1.setSpeed(150); //define motor1 speed: Motor1.run(FORWARD); //rotate motor1 cloclwise: Motor2.setSpeed(150); //define motor2 speed: Motor2.run(FORWARD); //rotate motor2 clockwise: Motor3.setSpeed(150); //define motor3 speed: Motor3.run(BACKWARD); //rotate motor3 anticlockwise: Motor4.setSpeed(150); //define motor4 speed: Motor4.run(BACKWARD); //rotate motor4 anticlockwise: delay(150); }else if((Right_Value==0)&&(Left_Value==1)) { //If the condition is 'true' then the statement below will execute: //Turn left Motor1.setSpeed(150); //define motor1 speed: Motor1.run(BACKWARD); //rotate motor1 anticlockwise: Motor2.setSpeed(150); //define motor2 speed: Motor2.run(BACKWARD); //rotate motor2 anticlockwise: Motor3.setSpeed(150); //define motor3 speed: Motor3.run(FORWARD); //rotate motor3 clockwise: Motor4.setSpeed(150); //define motor4 speed: Motor4.run(FORWARD); //rotate motor4 clockwise: delay(150); }else if(distance > d) { //If the condition is 'true' then the statement below will execute: stop(); } } void stop(){ //Stop Motor1.setSpeed(0); //define motor1 speed: Motor1.run(RELEASE); //stop motor1: Motor2.setSpeed(0); //define motor2 speed: Motor2.run(RELEASE); //stop motor2: Motor3.setSpeed(0); //define motor3 speed: Motor3.run(RELEASE); //stop motor3: Motor4.setSpeed(0); //define motor4 speed: Motor4.run(RELEASE); //stop motor4: }

WORKING PRINCIPLE

The ultrasonic sensor detects distance of a person in front. If the person is within range, the robot moves forward.

IR sensors help the robot adjust direction by detecting left and right movement.

Servo motor rotates the sensor to scan surroundings for better tracking.

STEPS

1. Connect all components as per circuit
2. Upload the code
3. Power the robot
4. Place object in front
5. Robot starts following

TIPS

• Adjust distance value for better tracking
• Use good battery
• Fix sensors properly

CONCLUSION

This human following robot is a great robotics project combining sensors and automation.