UAVCAN is an onboard network which allows the autopilot to connect to avionics. It supports hardware like:
In contrast to hobby-grade devices it uses rugged, differential signalling and supports firmware upgrades over the bus. All motor controllers provide status feedback and implement field-oriented-control (FOC).
The PX4 middleware will automatically upgrade firmware on UAVCAN nodes if the matching firmware is supplied. The process and requirements are described on the UAVCAN Firmware page.
The ID and rotational direction of each motor controller can be assigned after installation in a simple setup routine: UAVCAN Node Enumeration. The routine can be started by the user through QGroundControl.