Andrew Tridgell

thanks for all your work on this!

@auturgy we really only have CAS and TAS in ArduPilot. CAS includes compensation for the sensor offset and positional error (via ARSPD_RATIO), but no other factors. TAS is just CAS*EAS2TAS...

@IamPete1 actually, we do always include the airspeed ratio, which means what we will be sending is a CAS, not an IAS, so lets change this to AIRSPEED not AIRSPEED_RAW

> However we still do not to compressibility correction, so its not really CAS. compressibility is EAS (equivalent airspeed), not CAS (I got this wrong in my earlier comment, sorry)

I just tested this, and it does work without a compass in SITL. It works because EKF does init, and the check for using_gps only happens when armed

> I suggest fix some little bugs. thanks, added

> Should add AP_HAL_ADRC_RATE_CONTROLLER_ENABLED in Tools/scripts/build_options.py and use it. this is just an experiment, it would be structured quite differently if we were to consider it for merging into master

@reilly-callaway needs a rebase as conflicted, then ping me to merge this

I've assigned to @priseborough who wrote this code

tested on Pixhawk6X, works well!