About

This custom smart servo driver transforms standard RC servos (e.g., SG90) into high-performance smart servos. Using a custom circuit with an STM32 microcontroller, it enables advanced features such as PID control, low-pass filtering, and I2C communication. This affordable and innovative upgrade allows for smooth, precise, and customizable operation, making it suitable for various robotics applications.

View on GitHub

How It Works

LP2992 Voltage Regulator: Steps down 5V to 3.3V to power the STM32.
STM32 Microcontroller: The brain of the system, managing PID control, low-pass filtering, and I2C communication.
TL431 Precision Voltage Regulator: Produces a stable 2.495V reference voltage for the potentiometer, ensuring accurate angle detection.
Motor Driver IC: Amplifies PWM signals from the STM32 to drive the motor.

The PCB design maintains a large ground plane to improve noise resistance while separating noisy traces from those requiring stable voltage. Additionally, power is supplied via USB Type-C.

Specs and Results

Features:

PID control ensures smooth and precise operation.
I2C communication provides access to angle, speed, and output data.
Torque and control parameters can be adjusted.

Performance:

Operates at 200Hz for real-time responsiveness.
Low-pass filtering and precise voltage control enhance stability.
Supports hardware PWM, avoiding vibration issues caused by software PWM limitations.

Applications:

Robotics education and projects requiring speed control.
Compatibility with master devices like Raspberry Pi and Arduino.

This servo driver is an ideal solution for robotics enthusiasts seeking a high-functionality, cost-effective option. The design files and source code are available on GitHub, enabling further customization and exploration.

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