In the ArduSub control system, the flight controller board is the hardware component which the ArduSub autopilot firmware is loaded onto. The autopilot processes the pilot input and sensor data, and controls the motors, lights, servos, and relays on the vehicle.
Although there are many different flight controller boards available, here are the general characteristics:
The first flight controller board recommended for ArduSub was the Pixhawk 1 manufactured by 3D Robotics (3DR) from 2013-2016. When 3DR exited manufacturing hardware in 2016, different manufacturers took the open source design files and created their own flight controllers. The original Pixhawk design has been retired, and Blue Robotics has designed the Navigator as a modern replacement that is tailored to ArduSub use cases.
The following list is the recommended flight controller boards for use with ArduSub:
There is a comparison in the Blue Robotics Technical Reference.
With feedback from other users, the following flight controller boards are not recommended for use with Ardusub:
ArduPilot has has a list of other compatible flight controllers: Autopilot Hardware Options
These boards have not been tested or reported to work with ArduSub.