All Kalman gain calculations now explicity set gains for deactivated states to zero.
Previous use of loops to set gains to zero have been replaced with more efficient memset operations.
Adapt the lengths of the IMU and observations buffers on startup to the specified time delays and update rates.
This does require the EKF to be re-started if time delays are changed.
AP_NavEKF3: Implement same maths as PX4/ecl EKF
Replace attitude vector states with quaternions
Remove gyro scale factor states
Add XY accel delta velocity bias estimation
Initial tuning
Add GPS body frame offset compensation
AP_NavEKF3: Fix bugs and consolidate aiding switch logic
Switching in and out of aiding modes was being performed in more than one place and was using two variables.
The reversion out of GPS mode due to prolonged loss of GPS was not working.
This consolidates the logic and ensures that PV_AidingMode is only changed by the setAidingMode function.
AP_NavEKF3: prevent multiple fusion mode changes per filter update
AP_NavEKF3: Update tuning defaults
AP_NavEKF3: Fix bug causing switching in and out of aiding
If the GPS receiver was disconnected and no data received, then then the gpsGoodToAlign check did not get a chance to run and becasue it was previously true the EKF would switch back into aiding.
This prevents this by ensuring that gpsGoodToAlign defaults to false when the check is not being performed.
An additional check has also been dded to ensure that there is GPS data to fuse before we declare ready to use GPS.
AP_NavEKF3: Fix bug preventing planes recovering from bad magnetometers
This bug created a race condition whereby if the EKF had to reset the yaw to the GPS ground course to recover from a bad magnetometer, the new heading could be over-written by the bad magnetic heading when the plane reached the height for the scheduled reset.
AP_NavEKF3: Improve switch-over to backup magnetometer
When switching over to a back up magnetometer, ensure that the earth field estimate are reset. Otherwise mag earth field estimates due to the previous failed mag could cause data from the new mag to be rejected.
AP_NavEKF3: enable automatic use of range finder height
AP_NavEKF3: Fix bug in handling of invalid range data
AP_NavEKF3: Fix height drift on ground using range finder without GPSAP_NavEKF3:
AP_NavEKF3: Handle yaw jumps due to core switches
AP_NavEKF3: Enable simultaneous GPS and optical flow use
AP_NavEKF3: fix console status reporting
AP_NavEKF3: send messages to mavlink instead of console
This allows the GCS to better handle the display of messages to the user.
AP_NavEKF3: replace deprecated function call
AP_NavEKF3: Compensate for sensor body frame offsets
AP_NavEKF3: Fix bug in median filter code
AP_NavEKF3: save some memory in the position offsets in EKF3
We don't need to copy that vector3f for every sample. A uint8_t does the job
AP_NavEKF3: Add fusion of range beacon data
AP_NavEKF3: Bring up to date with EKF2
AP_NavEKF3: Misc range beacon updates
AP_NavEKF3: Add mising accessors
AP_NavEKF3: remove duplicate include
AP_NavEKF3: Prevent NaN's when accessing range beacon debug data
AP_NavEKF3: Update range beacon naming
AP_NavEKF3: updates
AP_NavEKF3: miscellaneous changes
AP_NavEKF3: misc updates
AP_NavEKF3: misc range beacons updates
AP_NavEKF3: add missing rover default param
Correction requires the body rates averaged across the flow sensor sampling interval. This data has been added to the sensor buffer.
The body rate data from the flow sensor driver does not contain the Z component, so an equivalent value sampled from the navigation IMU has been used instead.
The variable omegaAcrossFlowTime has been moved out of the class and into the only function that uses it.
Enables simultaneous use of GPS and optical flow data with automatic fallback to relative position mode if GPS is lost and automatic switch-up to absolute position status if GPS gained/re-gained.
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.
Switching in and out of aiding modes was being performed in more than one place and was using two variables.
The reversion out of GPS mode due to prolonged loss of GPS was not working.
This consolidates the logic and ensures that PV_AidingMode is only changed by the setAidingMode function.
The problem with using min() and max() is that they conflict with some
C++ headers. Name the macros in uppercase instead. We may go case by
case later converting them to be typesafe.
Changes generated with:
git ls-files '*.cpp' '*.h' -z | xargs -0 sed -i 's/\([^_[:alnum:]]\)max(/\1MAX(/g'
git ls-files '*.cpp' '*.h' -z | xargs -0 sed -i 's/\([^_[:alnum:]]\)min(/\1MIN(/g'
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.
GPS height has been added as a measurement option along with range finder and baro
Selection of the height measurement source has been moved into a separate function
Each height source is assigned its own measurement noise
If GPS or baro alt is not able to be used, it reverts to baro
When baro is not being used, an offset is continually calculated which enables a switch to baro without a height step.
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.
Don't fuse other measurements on the same frame that magnetometer measurements arrive if running at a high frame rate as there will be insufficient time to complete other operations.
Paul Riseborough
Arjun Vinod
Tom Pittenger
Peter Barker
priseborough
Andrew Tridgell
Mathieu OTHACEHE
Lucas De Marchi
Paul Riseborough
Siddharth Bharat Purohit