This fixes the cases where the yaw message from the GNSS receiver would
take more time than the vel/pos. The estimator should wait and not
immediately fall back to an other aiding source after 5sec.
If it never comes, it will never fall back, but this is ok since the
user wants to fly with GPS aiding an not with something else.
If the user selects GPS yaw fusion but that there is no GPS yaw data in
the GPS message or if the fusion is rejected for some time, the GPS yaw
data is declared faulty and the fusion is stopped to allow an other
source of yaw aiding to start.
- do not gps reference altitude to zero in case gps checks pass before the
filter initialized
- reset the filtered gps position and position derivative filters in case
we are in air or there is movement on the ground
Signed-off-by: RomanBapst <bapstroman@gmail.com>
The `_deadreckon_time_exceeded` flag is used in
`local_position_is_valid()`. This means that
`_params.valid_timeout_max` after startup, in my observed case 5
seconds, the local position switche from valid to invalid and then after
a while back to valid again.
With this fix, the local position is flagged invalid from boot and gets validated after the first aiding event.
Co-authored-by: Julian Oes <julian@oes.ch>
* ekf: disable xy accel bias learning before takeoff
As those biases are usually poorly observable before takeoff because
they are almost perpendicular to the gravity vector, learning is often
driven by noise and numerical issues. This results in incorrect bias
learning before takeoff when the drone is static on ground for a long
period of time.
* ekf: update unit test and change indicator
This is a non-functional change required to select accel bias estimation
per axis selection. The intent is then to disable the learning before
takeoff of the components that are poorly observable.
* Support vision velocity expressed in body frame
* Use switch statement for vision velocity frame
* Robustify vision velocity frame test
* Increase lower bound on vision velocity noise to 0.05 m/s
* EKF: Improve covariance prediction stability
Eliminates collapse of vertical velocity state variance due to rounding errors that can occur under some operating conditions.
* EKF: Fix typo
* test: Fix initialisation test cases
Provide sufficient time for variances to stabilise and fix calculation of reference quaternion for alignment.
* test: Allow for accumulated rounding error in IMU sampling test
* test: Allow sufficient time for quaternion variances to reduce after initial alignment
* test: Increase allowance for tilt alignment delay and inertial nav errors
* test: Increase allowance for tilt alignment delay and inertial nav errors
* adpat reset velocity test
* test: update change indication file
* test: Adjust tests to handle alignment time and prediction errors
* README.md: Add documentation for change indicator test
bresch