The system uses two LDR (Light Dependent Resistor) sensor modules placed on either side of a physical divider. Each module outputs a digital HIGH or LOW signal based on the light intensity it receives. The Arduino Nano reads these digital inputs; if one sensor detects more light than the other, it commands the SG90 servo motor to rotate the panel in that direction. Once both sensors receive equal light intensity, the servo stops, confirming the panel is directly aligned with the light source.
Why Build This
Increase the energy capture efficiency of small solar panels
Learn fundamental robotics and sensor integration
Great hands-on STEM project for renewable energy concepts
Real-World Application
Solar tracking systems are widely used in commercial solar farms and off-grid renewable energy installations to maximize daily photovoltaic power generation by keeping panels perpendicular to the sun.
Skills You'll Learn
Interface light-dependent resistors with microcontrollers
Control servo motors using PWM signals
Implement digital threshold logic for automated movement
Wire and power basic electronic circuits
Safety Precautions
Ensure correct polarity when connecting power and ground to the Arduino Nano, LDR modules, and servo motor to prevent component damage. Double-check all wiring before connecting the USB or 5V external power source. If testing with real solar panels outdoors, avoid exposing electronic components to rain or moisture.
Technology Tags
ARDUINO NANO
LDR SENSOR
SERVO MOTOR
SOLAR PANEL
BREADBOARD
Frequently Asked Questions
Yes, an Arduino Uno is fully compatible with this code and schematic, though its physical footprint is larger than the Nano.
This simplified beginner project uses LDR modules with built-in comparators that output digital HIGH/LOW signals, making threshold detection straightforward without needing analog-to-digital mapping.
While the 5V pin from the Arduino can power a small SG90 servo for testing, a separate stable 5V external power source is recommended if you experience resets or erratic servo jitter.
This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.
