I have noticed the worst latency case is tens milliseconds on RT Linux kernel patch,but to me ,that is not enough. I have a plane which is longitudinal unstable, so complicated control system is necessary in my case. The latency must lower than 5 milliseconds which means hard real time. So I want to know the feasibility of running the uCOS II on the Raspberry Pi. And is there drivers of NAVIO+ for uCOS II?

Max latency in real-time kernel is around ~60 microseconds, not milliseconds.
Porting APM to uCOSII on Raspberry Pi is an incredibly heavy task and mostly pointless as APM runs on Linux with real-time kernel absolutely fine.

Thanks.If it’s microseconds,then it will work.