I was working on this project for myself but if there is interest I might release the code/design to the public.
It’s a cheap flight controller. Uses a inexpensive Arduino uno + 4 or 5 rotary encoder knobs. (Total hardware cost ~$30 minus enclosure) Then a small program running in the background on the PC “listening” to the arduino.
When you turn or click (press down) the encoder the app sends keystrokes to the flight sim. For example spinning the knob I can adjust the autopilot altitude selection up and down. Proof of concept worked - I can spin the knobs and change heading , altitude, etc.
Only catch right now, there is a #%$@ software bug in the heading increase/decrease keyboard shortcut. If you move the heading bug for a while (with keyboard shortcut) it starts spinning in circles and crashes MSFS2020. I submitted a zendesk hopefully they fix that someday.
My thought was to mount the 5 rotary switches on a small box and have that for easy AP adjustments. But it can control anything with a knob and keyboard shortcut for adjustment. Each knob is also a push button which is cool. I’m shooting for 5 put need to see if I have enough pins on the arduino uno.