Flight stack on Android?
« on: October 27, 2018, 05:53:33 pm »
It looks like LibrePilot has Android app to help the guy on the ground but that the flight stack software does not run on Android.  Is this correct?   

Does anyone know any open source pilot software where the Android device is the hardware for the pilot software?  There are smart watches (like LEMFO LEMX) now that run full Android OS and have GPS, gyros, compass, camera (8 mp), G4 communications, light (90 grams with watchband), rugged, low power, waterproof, cheap ($170), etc.  Seems like nice hardware for autopilot.     I realize that Android is not a real time OS, and so not at all ideal software environment for pilot software to run in.  But I think it might be made to work well enough.   Each year I expect better and better Android watches to come out.  So in the long run it seems like a good hardware platform to develop for.   Anyone got any pointers or advice?

-- Vince Cate

Re: Flight stack on Android?
« Reply #1 on: October 27, 2018, 07:06:52 pm »
Just some opinions.

To do stabilization, you really need a real time OS, or simple deterministic code where the delays are limited and known.

Things like garbage collection, stacked up interrupts, opaque code behind sensor, storage device, telemetry, etc. access can lead to unknown or unquantifiable delays.  Not saying that Android has all these problems.  It's uncommon to even see Linux used as the OS for FCs doing stabilization, although there is a real-time variant of Linux.

It's possible to write stabilization code to run on Android, but it may not be possible to prove that always runs correctly due to unknown delays.