AP_NavEKF3: fix failure to arm with EK3_MAG_CAL = 7
AP_NavEKF3: Fix failure to arm when not using magnetometer
AP_NavEKF3: Reduce yaw drift when EK3_MAG_CAL = 7
AP_NavEKF3: Add emergency yaw reset using a Gussian Sum Filter estimate
AP_NavEKF3: Reduce default minimum GPS velocity noise for Copters
Enables fail-safe to be set with more sensitivity and improves tracking accuracy.
Origin values were set using typical GPS performance for receivers on sale 6 years ago. Receiver performance has improved since then.
AP_NavEKF3: Prevent constant mag anomaly yaw resets
Prevents constant magnetic anomaly induced resets that can be triggered when flying with vehicle generated magnetic interference.
Allows for two resets per takeoff. Allowance for two resets is required, becasue a large ground based magnetic yaw anomaly can cause a sufficiently large yaw innovation that two resets in close succession are required.
AP_NavEKF3: Add option to fly without magnetometer
AP_NavEKF3: Rework emergency yaw reset logic
Use a separate external accessor function to request the yaw reset.
Allow reset requests to remain active for a defined period of time.
Tidy up reset function to split out accuracy check.
AP_NavEKF3: Fix vulnerability to lane switch race condition
Prevents the situation where a lane switch results in a lane being selected that does not have the correct yaw. This can occur if the primary lane becomes unhealthy before the external failsafe monitor has time to react.
AP_NavEKF3: Fix EKF_MAG_CAL = 6 behaviours
Fix bug causing the yaw alignment to be performed at startup before the GSF had a valid estimate.
Fix bug causing emergency yaw message to be output for a normal reset.
Fix vulnerability to reported negative yaw variance.
Remove duplicate timer checks.
AP_NavEKF3: Update EK3_MAG_CAL documentation
AP_NavEKF3: Relax yaw gyro bias convergence check when not using mag
AP_NavEKF3: Reduce yaw drift in hover with no yaw sensor
Uses the GSF yaw estimate if available which is better than the EKF's own yaw when no yaw sensor is available.
Adapted from EKF2 implementation as of commits
3835d2613, e9ed3540f and df4fc0fff
this sets a limit on the difference between the earth field from the
WMM tables and the learned earth field inside the EKF. Setting it to
zero disables the feature. A positive value sets the limit in mGauss.
this moves intermediate variables from being per-core to being common
between cores. This saves memory on systems with more than one core by
avoiding allocating this memory on every core.
This is an alternative to #11717 which moves memory onto the stack. It
doesn't save as much memory as #11717, but avoids creating large stack
frames
This avoids creating two pointers of different types to the same memory.
Having two pointers to the same memory can lead to the compiler
optimising code such that a write to one pointer is rearranged to be
either before or after a read from the other pointer depending on
which is deemed faster - not a good outcome.
This change means that provided the GPS_DELAY_MS parameters are set for each GPS receiver attached, the EKF will not have to wait for the configuration of each receiver to be determined before it can start.
This significantly reduces start-up times when the delay parameters are set.
If variance falls below desired minimum, set state noise to a larger value.
If variance drops below safe value, set to desired minimum and reset off-diagonals to zero.
To eliminate the possibility of editing errors, revert the covariance prediction auto-code to the original auto-code without the replacement fo the /2 and /4 operations. The compiler optimisations are able to correctly handle the /2 and /4 operations.
Also use local variables for intermediate covariance calculations. The use of class variables for these small arrays was unnecessary.
This patch ensures that covariance matrix entries for inactive states are always set to zero.
It also halves the number of copy operations from the updated to stored matrix.
Fix rounding error bug preventing state from updating after initial convergence.
Decouple GPS reference height from published EKf origin height.
Add bitmask parameter to control update and publishing of GPS reference height.
