Hi all,
my project :
So I'm literally building a homemade heavy RC vehicle from scratch. More info here :
my issue :
I've been kind of stuck on this problem for a year now : I need a duplex communication that is fast enough to send data back and forth from the radio to the vehicle AND from the vehicle to the radio. I'm using an arduino mega 2560 on both sides.
data rate :
I need to send data (lets say 20 bytes) from the radio to the vehicle at least every 40ms. the other way around is less critical. even if ideally the same speed would be appreciated, every 1s would do.
range :
a few hundred meters on open field would be good.
What I tried :
First, I used nrf24l01 modules :
It's been very hard for me and took me weeks to code. I used Robin2 tutorial found on this forum, (big thanks if you were to read this !!). The communication speed was good enough but signal quality was worryingly poor (lots of losses of connections if too close, too far, or if a single house is in between... And I can't afford loosing signal for several seconds...
Now I'm trying to use a pair of AI thinker LoRa 1276 module :
It turned easier to program, signal looks much better, but I can't seem to find a way to exchange data fast enough : If I try to send data more often than 100ms from the radio, then the radio won't receive data from the vehicle... Moreover, when the vehicle module is sending data, the servo control is interrupted for a few ms, well long enough to be noticed...
I spent hours of searches on the internet, and I'm running out of ideas. I'm actually wondering if what I am trying to do is achievable with an arduino and compatible radio modules...
Does anyone know how to achieve that ? Any module recommendation ? I guess would even be willing to spend up to $200 for a couple quality modules easy to program, if I'm sure it would work.
Before you ask :
NO I CANNOT use a remote control system from conventional rc vehicles :
-I need about 20 different bytes of data to send
-I need to be able to program what the data will do. e.g. : when pushing a single shift button -> disengage engine clutch -> shift to neutral -> read sensors -> shift gear -> Give engine control back to pilot. This is very unlikely to be done with conventional RC off the shelf components.
-I need the remote to be modular as the project evolves.
-I need to be able to find spare and standard components for a long time. This is a lifetime project.
Yes I can post my codes if needed, but I think it should be on another topic, since whats I'm asking here, is if such fast duplex communication can be achieved with arduino, if so : how ?
Bonus Question : Why in the world is it so difficult to program fast duplex radio communication when it is so easy to program a lcd screen or a semi automatic gearbox ??
thanks