@tridge, BRL is suited for running at a lower rate than the main loop, but it requires quite it a bit of resources. Ultimately, the issue is that it scales roughly exponentially in the planning horizon, in terms of both CPU and memory. There are ways to reduce these requirements somewhat, especially for memory, but it is still too heavy to run on a Pixhawk comfortably.
Running ArduPilot on RPi3 is a more appealing option for BRL-based drone control -- thank you, I'll look into that! However, having LowPriMath would still be very useful! Lighter-weight approaches at the intersection of AI and control could make use of it.