I sponsored and did quite a bit of work to help with my brother’s quadcopter when he was back in highschool. Here’s the code Github page.
The basic idea was to try using a tiny x86 board with TCP/IP over WiFi, and a Ground Control Station. We used QGroundControl as the GCS. We were using ESCs flashed with SimonK, a YEI 500Hz AHRS, and a Maestro USB-PWM adapter. Although using x86 and custom-writing the flight control software wasn’t a good idea, in retrospect, it still sort of worked.