Imu 2.0

So with the IMU now bolted to the fuselage, vibration is definitely worse than the skid mounted IMU but miraculously the Kalman seems more stable and more accurate with it.

The common technique in testing attitude hold is to fix the heading to 0 so you don't have to worry about body frame conversions. What always happens with that is a pitch up, gimbal lock, and autopilot terrorism.

With the strap-on IMU, we had record attitude + altitude + velocity holds up to 88 seconds. Yet another incremental improvement but still showing unstable tilt oscillation and high velocities. The flight data shows the strap-on IMU with high sample rates to be just as slow at producing equivalent accuracy as the skid mounted IMU with low sample rates.

Instead of averaging more samples on the PIC, we're using a smaller DT/integration step in the Kalman filter with the higher sample rate. That and the fuselage mounting seems to be the magic touch.

So with the weather and the lack of open space, 1 test flight per day is the most that we can pull off even without a day job. With the amount of data generated by these flights and the preparation for each flight, 1 flight per day is probably the best in any circumstance.