See discussion here:
https://github.com/ArduPilot/ardupilot/issues/7331
we were getting some uninitialised variables. While it only showed up in
AP_SbusOut, it means we can't be sure it won't happen on other objects,
so safest to remove the approach
Thanks to assistance from Lucas, Peter and Francisco
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
Revert "AP_NavEKF2: Fix bug in published yaw reset value found during code review"
commit 175faf1e4184f9000aaaf77f56ae0877ab2ffefe.
Revert "AP_NavEKF2: use a struct for all yaw step class variables"
commit 77fad065d15ea86cb309a6824c662f952070b5c7.
Partially revert "AP_NavEKF2: Handle yaw jumps due to core switches"
commit 885bfd1b4e8fb5136af3880dadb731081d294cd0.
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.
Michael du Breuil
Paul Riseborough
Mark Whitehorn
Arjun Vinod
chobits
Peter Barker
Paul Riseborough
Andrew Tridgell
Lucas De Marchi
Dr.-Ing. Amilcar Do Carmo Lucas
Randy Mackay
Jacob Walser
Mathieu OTHACEHE
Francisco Ferreira