Toggling between alt sources in flight using the parameter can have unpredictable effects due to the various height offsets and the possibility that the data source may be unavailable.
Previous default was to apply in-flight height origin changes to local position instead of to reported origin height. This caused problems with copters that took off before getting GPS lock.
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.
this changes the stragegy for load levelling between EKF cores so it
works between EK2 and EK3, and with future estimators as well.
It allows us to run EK3 and EK2 at the same time with good scheduling
performance
Fixes a bug that allows the last reported reset time to to wind back and an out of date reset delta to be reported if a switch to a core that has previously been reset occurs.
Allows multiple consumers provided they access on the same frame.
Fixes a bug that allows the last reported reset time to to wind back and an out of date reset delta to be reported if a switch to a core that has previously been reset occurs.
Allows multiple consumers provided they access on the same frame.
Fixes a bug that allows the last reported reset time to to wind back and an out of date reset delta to be reported if a switch to a core that has previously been reset occurs.
Allows multiple consumers provided they access on the same frame
1) Do not switch to a core until its states have been updated.
2) Distinguish between mandated switches required for health failure and optional switches required due to innovation checks failing.
3) Apply hyseresis to innovation check levels
Revert "AP_NavEKF2: Fix bug in published yaw reset value found during code review"
commit 175faf1e41.
Revert "AP_NavEKF2: use a struct for all yaw step class variables"
commit 77fad065d1.
Partially revert "AP_NavEKF2: Handle yaw jumps due to core switches"
commit 885bfd1b4e.
The EK2_RNG_USE_HGT parameter sets the height (expressed as a percentage of the maximum range of the range finder as set by the RNGFND_MAX_CM parameter) below which the range finder will be used as the primary height source when the vehicle is moving slowly.
When using a height reference other than GPS, the height datum can drift due to air pressure changes if using baro, or due to terrain height changes if using range finder as the primary height source. To ensure that a consistent height datum is available when switching between altitude sources, the WGS-84 height estimate of the EKF's local positi norigin is updated using a
single state Bayes estimator,
If rngfinder or gps height data is lost whilst being used, there will be a fall-back to baro data.
Fixes a problem observed in a flight log where rapid temperature change caused the accel bias to change faster than the EKF could keep up.
This allows the bias to be learned faster but with acceptable level of noise in the estimate
Allow different process noise to be set for body (sensor bias) and earth field states.
This allows a stable magnetometer bias estimate to be available at end of flight whilst still allowing for external magnetic anomalies during landing.
Adjust default values to give stable mag bias learning and fast learning of external anomalies.
Automatically use the highest gain consistent with a 5% overshoot to minimise RMS tracking errors.
Provide an alternative correction method for the position and velocity states that allows the user to specify the time-constant. This can be used to fine tune the output observer for for platform specific sensor errors and control loop sensitivity estimation noise.
M_NSE is a measurement noise
P_NSE is a observation noise
I_GATE is an innovation gate
This also ensures the new parameter values required to use the EKF2 will be enforced.
Change to user adjustable fusion of constant position (as per legacy EKF) instead of constant velocity.
Enable user to specify use of 3-axis magnetometer fusion when operating without aiding.
Don't allow gyro scale factor learning without external aiding data as it can be unreliable
Sensor bias corrections were being applied to the incoming IMU data using the wrong delta time.
This was what was driving the different tuning between plane and copter for gyro bias process noise so the same gyro bias process noise default tuning value can now be used for all platform types.
Sensor bias corrections were being applied a a second time to the output observer inertial data.
Eliminate the use of horizontal position states during non-aiding operation to make it easier to tune.
Explicitly set the horizontal position associated Kalman gains to zero and the coresponding covariance entries to zero after avery fusion operation.
Make the horizontal velocity observation noise used during non-aiding operation adjustable.
Use a fixed value of velocity noise during initial alignment so that the flight peformance can be tuned without affecting the initial alignment.
The ad-hoc scaling of error growth has been replaced with a consistent method that uses the main nav filters published vertical velocity uncertainty and the terrain gradient assumption.
Down-sample the IMU and output observer state data to 100Hz for storage in the buffer.
This reduces storage requirements for Copter by 75% or 6KB
It does not affect memory required by plane which already uses short buffers due to its 50Hz execution rate.
This means that the EKF filter operations operate at a maximum rate of 100Hz.
The output observer continues to operate at 400Hz and coning and sculling corrections are applied during the down-sampling so there is no loss of accuracy.
Peter Barker
bugobliterator
priseborough
Dr.-Ing. Amilcar Do Carmo Lucas
Andrew Tridgell
Randy Mackay
Jacob Walser
Michael du Breuil
Mathieu OTHACEHE
Francisco Ferreira
Jonathan Challinger
Tom Pittenger
Ricardo de Almeida Gonzaga
Don Gagne
Paul Riseborough