Hi,
I’m using ArduPlane version 4.5.7 and want to clarify how the logic works regarding fallback from EKF to DCM when sensors (e.g. air‑speed, barometer) fail. Specifically:
– If AHRS_OPTIONS is set to DisableDCMFallback (either FW or VTOL), and EKF becomes “unhealthy” due to sensor failures (not just GPS loss), will the autopilot still force fallback to DCM?
– Or does DisableDCMFallback guarantee that DCM will not be used at all, regardless of EKF health?
– Is there any case / commit / documented behavior where the fallback override (DisableDCMFallback) is intentionally ignored in presence of sensor-fault or critical EKF failure?
I looked through the code (AP_AHRS.cpp) and did not find a clear “override fallback on sensor fault” path.
Would appreciate clarification — maybe a pointer to relevant code, issue or design rationale.
Thanks in advance!