Sunlight Tracker

A sunlight tracker is a system that follows the direction of sunlight. It is commonly used in solar panel systems to improve efficiency.

In this project, we use two Light Dependent Resistors (LDRs) to detect light intensity and a servo motor to move toward the brighter direction.

• Arduino Uno

• 2 × LDR (Light Dependent Resistor)

• 2 × 10kΩ Resistors

• 1 × Servo Motor

• Breadboard

• Jumper Wires

• LDR sensors change resistance based on light intensity.

• Two LDRs are placed on opposite sides (left and right).

• Arduino reads analog values from both sensors.

• The system compares both values:

- If left side receives more light → servo moves left

- If right side receives more light → servo moves right

• A threshold is used to avoid unnecessary movement

• Left LDR connected to analog pin A0

• Right LDR connected to analog pin A1

• Servo motor connected to digital pin D9

• Each LDR forms a voltage divider with a 10kΩ resistor

1. Initialize servo at 90° (center position)

2. Read values from both LDRs

3. Compare light intensity

4. Adjust servo position accordingly

5. Repeat continuously

The system can be programmed using:

• Arduino IDE (text-based coding)

• PictoBlox (block-based coding)

Main logic:

• Read analog inputs

• Compare values

• Control servo movement

• Solar panel tracking systems

• Smart street lighting

• Light-following robots

• Energy-efficient systems

• Simple and low-cost

• Easy to build and understand

• Improves efficiency of solar systems

• Dual-axis solar tracking

• Integration with IoT (remote monitoring)

• Use of more precise sensors

This project demonstrates how sensors and actuators can be combined to create an intelligent system. It is a great beginner-level robotics project that introduces automation, sensor integration, and real-world applications.