How to Build an Arduino Light-Tracking Robot with LDR Sensors - Beginner Guide
Objective
This guide will walk you through building a light-tracking robot using Arduino and LDR sensors. You will learn to make the robot detect light and move toward it by controlling motors based on LDR sensor readings.
Project Goals
- Understand and use LDR sensors for light detection.
- Control motors based on sensor input using Arduino.
- Build a simple light-tracking robot with beginner-friendly code.
Required Components
| Component | Description | Link |
|---|---|---|
| Arduino Uno | Main microcontroller for controlling sensors and motors | Amazon Link |
| LDR (2 units) | Detects light intensity for tracking | Amazon Link |
| Motors (2 units) | Drives the robot movement | Amazon Link |
| Motor Driver Module | Controls motor directions | Check Availability |
| Jumper Wires | Connects components to Arduino | Amazon Link |
| Breadboard | For prototyping connections | Amazon Link |
| Power Supply | Powers Arduino and motors | Amazon Link |
Understanding LDR Sensors
An LDR, or Light Dependent Resistor, changes its resistance based on light intensity. As light increases, the resistance decreases, making it ideal for light-seeking robots.
Circuit Connection
| Component | Arduino Pin | Details |
|---|---|---|
| Left LDR | Pin 8 | Detects light on the left side |
| Right LDR | Pin 9 | Detects light on the right side |
| Left Motor | Pin 10 | Controls left motor |
| Right Motor | Pin 11 | Controls right motor |
| Motor Driver Module | Controls motor direction | Required for motor control |
How the Robot Works
The LDR sensors detect light levels. If both LDRs detect light, the robot moves forward. If only one detects light, the robot turns in that direction, and if neither detects light, it stops.
Arduino Code
#define LeftLDR 8
#define RightLDR 9
#define LeftMotor 10
#define RightMotor 11
#define MotorSpeed 255
void setup() {
Serial.begin(115200);
pinMode(LeftLDR, INPUT);
pinMode(RightLDR, INPUT);
pinMode(LeftMotor, OUTPUT);
pinMode(RightMotor, OUTPUT);
}
void loop() {
if (!digitalRead(LeftLDR) && !digitalRead(RightLDR)) {
digitalWrite(LeftMotor, MotorSpeed);
digitalWrite(RightMotor, MotorSpeed);
}
else if (!digitalRead(LeftLDR)) {
digitalWrite(LeftMotor, 0);
digitalWrite(RightMotor, MotorSpeed);
}
else if (!digitalRead(RightLDR)) {
digitalWrite(LeftMotor, MotorSpeed);
digitalWrite(RightMotor, 0);
}
else {
digitalWrite(LeftMotor, 0);
digitalWrite(RightMotor, 0);
}
}
Steps to Upload and Run
- Connect the Arduino board to your computer.
- Paste the code into the Arduino IDE, select the correct board and port, and upload the code.
- Test the robot by moving a light source around it to observe movement.
Troubleshooting Tips
- If motors are unresponsive, verify motor and power connections.
- Check that the Arduino is correctly connected and the code is uploaded successfully.
Suggestions for Beginners
Start with simple sensor and motor control projects before moving to more complex robotics. Understanding these basics will give you a strong foundation for future projects.
Recommended Book for Learning Arduino
Arduino Programming for Absolute Beginners – This book provides easy, step-by-step projects that are perfect for building confidence with Arduino.
For more free tutorials, visit MechatronicsLab.net for resources on Arduino, ESP32, and more.
No comments