Overview
This line follower robot is built using an ESP32, TB6612FNG motor driver, 8-channel IR sensor array, and N20 motors. The bot uses PID control for smooth and accurate tracking of black lines on white surfaces. A button toggles start/stop mode, and all logic runs onboard with PWM motor control.
How It Works
- IR array reads line position and converts it to a weighted value (0–700).
- Bot calculates deviation from center (error = 350 - position).
- PID logic adjusts motor speeds to minimize the error.
- PWM is applied using ledcWrite to smoothly vary motor speeds.
- Button toggles run state, and serial debug prints IR + error values.
Code & Tuning
The PID controller uses Kp = 30 and Kd = 20. Ki is kept at 0 to avoid integral windup. The bot performs best at medium speed on sharp and smooth curves. The IR sensor values are inverted using !digitalRead() for compatibility with black-line-on-white tracks.