Part 1: latitude/longitude hold
I am posting an example with relaxed altitude hold (+/-10m vs 50mAGL) using 6DOF IMU autopilot.
GPS reception notoriously drops from 10 to 4 sats because of heavy roll (up to 40 commanded and some 50 achieved roll - 6-11m/s windgusts).
My goal was to achieve dogfight-like performance from rudder-only navigation.
Because I used full IMU autopilot, the navigation was smooth and reliable even when the GPS course was jumping at times.
The autopilot is a prototype used the previous year for winter tests. This time, I am focusing on optimising it for the most popular amateur UAV platform.
The navigation algorithm was brutal (not used in regular navigation in this autopilot which loiters around waypoint): hit home position with max allowed roll of 40deg.
Further technical details are not yet released.
This time GPS home position stayed in place, but at my location it likes to drift around by 50m every few minutes depending on the choice of satellites (no EGNOS enabled).