I am making some education software that will use drones. I want to learn a lot about the avionics theory involved in drone flight (IMU, PID, Mix Table, etc). I need that rather than building the drone and uploading the software type info. Anyone know good education resources on the drone avionics ? I found one book called “Teach an Arduino to Fly” by David McGriffy but I am in Korea and can’t ship a book (and prefer pdfs to eReaders…). Maybe there is some university class that covers this and is uploaded online ? Thanks!