Hardware Design

This project includes a full KiCad schematic for accurate electrical documentation.

Power Architecture

The system uses: - 5V rail for buzzer and motor driver logic - 3.3V logic for ESP32

All grounds are common.

Buzzer Driver

The buzzer is driven using a BC547 NPN transistor:

• GPIO33 → 1kΩ resistor → Base
• Emitter → GND
• Collector → Buzzer negative
• Buzzer positive → 5V

This ensures: - Proper volume - No GPIO overcurrent - Stable system operation

Motor Driver

The motor driver is controlled via 4 PWM channels.

Differential drive logic is implemented in firmware.