* Revert "EKF: Release flow speed limit with altitude gained"
This reverts commit e70206f74bc4f77a0e000da3c923f4459006d2b1.
* Revert "fix code style"
This reverts commit 76bf70121c37e2c1ec74982eb8c26e0510b2c84a.
* Revert "Reverse the linked list of data_validator_group and maintain a first node"
This reverts commit 32482e7644d14d7e4d0e25183b0dc9b0f27bf9c1.
* fix typo
* EKF: use baro if it was reset to baro from ev
* EKF: set vert_pos_reset if resetting to ev hgt
otherwise the position controller will not reset the setpoint -> leading to unwanted altitude changes
When GPS use is gained whilst flying using optical flow data, the sudden release of the speed limit is unannounced to the operator and can cause unexpected acceleration.
This patch releases the speed limit as height is gained, but does not reduce it when the vehicle descends, unless GPS use is lost.
If state errors were large before the reset, then failure to reset the covariance matrix terms can result in incorrect fusion of position and velocity measurements after the reset due to inconsistencies in the covariance matrix.
When performing the initial in-flight mag yaw reset for RW vehicle, do not reset the quaternion states and corresponding variances unless there has been a change in yaw angle large enough to cause problems with navigation.
This is because the state estimates after a reset are more vulnerable to transient sensor errors, so a reset should be avoided if possible.
When performing the initial in-flight magnetic field reset for fixed wing vehicles, resetting the quaternion states and their corresponding covariances should be avoided unless yaw errors are large, because state estimates are vulnerable to transient sensor errors immediately following a reset.
Ensures that a complete reset of velocity and position states will always be performed if yaw has had to be reset using GPS velocity.
Ensures that the yaw_align status cannot be set to false once the filter has aligned.
Fuse external vision data using a relative position odometry method when GPS data is also being used and enable both GPOS and EV data to be fused on the same time step.
Use horizontal acceleration to check if yaw is observable independent of the magnetometer.
Use rotation about the vertical to check if mag raises are observable.
If neither yaw of mag biases are observable, save the magnetic field variances and switch to magnetic yaw fusion.
Use the last learned declination when using magnetic yaw fusion so that the yaw reference remains consistent.
When yaw or biases become observable, reinstate the saved variances and switch back to 3D mag fusion.
Add a bitmask parameter to control bias learning for individual axes. This is achieved by setting the disabled states to zero together with their corresponding covariances.
Minor cleanup of the covariance prediction comments.
Removal of unnecessary variable copy operations.
Replace index operations to initialise covariance to zero with the more efficient memset.
This change removes the following compiler error when building using the ARM cross compiler.
/Users/paul/src/Firmware/src/lib/ecl/EKF/ekf_helper.cpp:45:12: error: 'std::abs' has not been declared
using std::abs;
