Hi all,
I’m trying to read a reasonably accurate barometric altitude in GUIDED_NOGPS but struggling with the correct message to read it from.
The EKF alt origin is correctly set to a valid AMSL via SET_GPS_GLOBAL_ORIGIN followed by DO_SET_HOME cmd
EK3_SRC is correctly set for baro/compass only
GLOBAL_POSITION_ALT.alt returns the static alt from the EKF origin
VFR_HUD.alt returns the same static value that never changes even after arming/takeoff
GLOBAL_POSITION_ALT.relativeAlt is wildly inaccurate and and vary from -80m to +120m when stationary.
AHRS2.alt returns the same value as above
I have also tried calculating altitude from QNH and SCALED_PRESSURE.pressAbs from the barometer to create an offset from the EKF origin and write to BARO_ALT_OFFSET
I can’t find a any message combination that gives me QFE and a relative alt from home.
Could someone clarify how altitude and the EK3 is expected to work in GUIDED_NOGPS
Cheers,
N