The position reset was not being compensated for velocity and measurement delay
The height was being reset with the position. It has been moved into a separate reset function
The maximum accepted GPS delay of 100msec was inadequate
The states was being incorrectly reset to the GPS position and Baro height on initial alignment.
When fusing 3-axis magnetometer data without absolute external aiding leg GPS), the declination is ultimately unobservable and the declination of the field states and the vehicle heading will slowly drift over time. To prevent this we need to fuse in a declination to constraint the NE earth field estimates.
the delta angle bias was applied to imu data which was not coming in the same
time intervall as the filter was operating. Therefore, the delta angle bias
applied to new imu data had to be scaled correctly in order to match
the imu time interval.
Use the gravity vector to estimate the initial roll and pitch angle
Use the projection of the magnetic field measurement onto the earth axis horizontal plane to calculate the initial heading
Paul Riseborough
Lorenz Meier
Roman
bugobliterator