The entire stack needed to run a motion axis, from motor and driver to controller and encoder, usually means sourcing and wiring together several separate boards. The Gearotons M17 collapses all four into a single NEMA-17 package with no protrusions, and the hardware design files, STM32G0 firmware, and Python/Arduino libraries are all MIT-licensed. Four models span 0.28 to 0.65 N·m of rated torque, ranging from 3.35 cm (1.3 inches) to 5.97 cm (2.4 inches) tall and 210 to 470 grams (0.46 to 1.04 lbs), all sharing the standard 42.2 mm (1.66 inch) NEMA-17 faceplate and a 5 mm shaft.
An ST STM32G0 Arm Cortex-M0+ microcontroller runs a closed-loop PID control loop at 32 kHz, giving the M17 higher power efficiency than a conventional open-loop stepper while maintaining the same torque-to-weight ratio. Communication happens over RS-485 at 230,400 baud, and multiple motors daisy-chain on a single pair of wires, each addressable by a 64-bit unique ID or a one-byte alias. The motors accept 12 V to 24 V DC input with integrated over-current, over-voltage, and over-temperature protection, and top out at 560 RPM.
The M17 works with Raspberry Pi, Arduino, and ESP32 boards, as well as standard PCs and Macs, via a USB-to-RS-485 adapter. Beyond the Python and Arduino libraries, Gearotons publishes a dedicated MCP server that exposes the motor's full 48-command firmware interface to AI assistants like Claude Desktop and Claude Code, letting users drive real hardware from natural language. The MCP server and Python tooling handle port discovery through pyserial, enumerating /dev/ttyUSB* devices and auto-detecting every motor on the bus on Linux the same way they do on macOS and Windows, with no custom kernel driver involved, and the server is also distributed on PyPI as servomotor-mcp for a plain pip install. KiCad schematics and 3D model files are included in the main repository, making the M17 one of the more complete open-source hardware motor projects available.
The four M17 variants sell for $20 to $35 (€18 to €32) through the Gearotons store, with a USB-to-RS-485 adapter available for $10 (€9). The project was demonstrated at Maker Faire Shenzhen 2025 by founder Tom Rodinger, and documentation with tutorials and code samples is available alongside the GitHub repositories.
