Don't do bias estimation if tilted by more than 60 degrees to prevent scale
factor errors affecting result unnecessarily.
Prevent Kalman gain from having the wrong sign due to numerical errors
associated with small process noise values.
Allow smaller Z accel bias process noise values to be set
Bring Plane glitch protection thresholds into alignment with copter and
rover
Slight increase in accelerometer bias process noise to prevent bias
estimate divergence into limits (Rover and Plane only as Copter does not
seem respond as well to this change)
effective increase in threshold on divergence test to allow increased
margin for bad GPS velocities
Fix#1068. When receiving guided waypoints do not change to GUIDED mode. This serves as a safety precaution for GCS, since they must switch to guided mode before sending the waypoints.
Divergence is now detected by looking for very large changes in the gyro
bias. This will cause the filter to be reset and declared unhealthy for
10 seconds.
Don't reset filterDiverged status immediately during reset
Set filterDiverged true if covariance blows up
Add fault status reporting
This will enable in-flight magnetometer calibration to be inhibited unconditionally,
This is required for long balloon carriage flights where ground speed can be high
enough to put it into in-air state, but with very poor observability of magnetic field
states causing bad state estimates and heading offsets to develop over time.
The covariance matrix no longer has rows and columns artificially zeroed when in static
mode. Instead booleans indicating whether wind or magentic field state estimation is
active are used to:
a) Set the process noise on these states to zero to stop their variances from increasing
unchecked when not being updated, and
b) Turn off updates for these states when measurement fusion is being performed.
This reduces the likelihood of a badly conditioned covariance matrix forming
during static mode operation.
A filter divergence check has also been added that will declare the filter unhealthy if
position, velocity and magnetic field observations are all failing their innovation
consistency checks. This unhealthy status will persist for 10 seconds after the
condition clears.
AP_NavEKF: Remove unnecessary zeroing of wind covariances