Arduino project · Motors and movement · Medium
Light Avoiding Robot Car (Shadow Seeker)
The car steers away from bright light and looks for shade.
What you will learn
- How to swap behaviour by swapping outputs
- How a robot can avoid light
- How cockroaches avoid light
How it works
If the left sensor is brighter, the car turns right (away). If the right sensor is brighter, it turns left. The Compare step checks one sensor against another, so you do not need to set a fixed number.
Try this next
- Stop when it is in the dark.
- Add a buzzer when it reaches shade.
- Compare with the light following car.
The simulator program and explanation on this page are original. The idea follows a classic Arduino project that students have built for years.
Parts: sensors and actuators (tap to show or hide)
Try the inputs (virtual sensors)
Pins (you can change them)
| Part | Arduino pin (change it here) | How to wire it |
|---|
Every wire, one by one
Red rail = 5 V from the Arduino 5V pin. Black rail = GND. The coloured wires carry signals. Match the wire colours on the drawing to this list.
| # | Colour | From (part and leg) | To |
|---|
Steps run from top to bottom, then start again. While the simulation runs, the active step is highlighted in green.
Quantities come from the parts you added. The store links open a search for that item on Robu.in, Amazon.in and ThinkRobotics, so you always see what is in stock today. Check the model, voltage and price before you order.
| # | Item | Qty | Search term | Buy / compare |
|---|
The PDF has the circuit sketch, pin table, every wire, sequence, full code, the parts list with store links, do’s and don’ts for each part, and the safety notes. The project file lets you come back and keep editing.
In the real world
A robot in a warehouse
The sensor sees the crates and the robot steers around them.
Tip: use the gold tab at the bottom of the circuit drawing to pull the real-world view up over the Arduino board. Your parts stay visible above it, so you can press a button and watch the real scene react.
- Sensors = what the robot sees
- Car = the robot driving