RC Maze Solver Car

A line-following RC car that solves mazes using four IR sensors and an Arduino.

Features

• 4 IR sensors (center left/right, side left/right) for wall detection
• Differential drive with two DC motors and L298N driver
• Auto-turn logic to handle T-junctions and dead ends
• Modular code structure for easy tweaking of speeds and thresholds

Hardware

• Arduino Uno (or clone)
• L298N Dual H-bridge motor driver
• 2 × DC motors + wheels
• 4 × IR obstacle/line sensors
• Battery pack or DC power convertor
• Jumper wires, chassis

Signal	Arduino Pin
IR Center R	7
IR Center L	8
IR Left	6
IR Right	11
Motor IN1	2
Motor IN2	3
Motor IN3	4
Motor IN4	5
ENA (Motor A)	9
ENB (Motor B)	10

Software / Usage

1. Open src/MazeSolver.ino in the Arduino IDE.
2. Select the correct board & COM port.
3. Upload.

Code Overview

• getReadings() reads all four IR sensors.
• forward(), turn_left(), turn_right(), reverse(), stop() wrap motor commands.
• The main loop() uses flag variables to remember last turn direction and implements:
  • Straight-ahead when both center sensors see no wall.
  • Gentle corrections when only one center sensor is triggered.
  • Sharp turns on side-sensor triggers.
  • Reverse and re-route on dead ends.

License

MIT © 2025 Kareem Abdelaziz