Hello Everyone,

I am new to this forum, sorry if my question is stupid.

I am planning a project where I want to control some RC vehicle (car/drone/boat etc.) with a simple self-written Android app.

I have a good experience with Flysky systems, so I am thinking to build the whole stuff on this. Also Flysky system could act as a backup control in case of issues with the Android app or smartphone itself.

Do you guys think it is possible to:
- write a simple Android app with speed&direction controls -> connect Arduino to smartphone via OTG -> Arduino connects to some Flysky or FS compatible transmitter module -> transmitter modul connects to FlySky receiver as it does normally...

Based on my findings on the internet, Android phone + Arduino communication is possible and quite easy to do, what do you think about the other parts?

How could I establish communication between Arduino and Flysky? I have found some generic RC module NRF24L01, could this be paired with Flysky receivers?

The reason I insist to use Flysky is to be able to use my already owned FS transmitter, even as a backup. Also, this system has great range and stability for me.

I am really interested in your thoughts about the topic!

Thanks in advance,
Milan

It's possible, but not easy.

Flysky protocols use the A7105 radio chip, the different chips aren't compatible over the air.

Interfacing the A7105 from Arduino is possible (you will find examples on the internet) but making a FS-compatible transmitter is more complicated; the protocol (AFHDS 2A) involves accurate timing when hopping between channels.

Fortunately the Deviation open source tx firmware is an already-written transmitter code which does AFHDS2A as well as other protocols.