EKF2 range sensor fuse vs fallback


I’m running PX4 v1.14 on a multicopter with a height range sensor, and vision messages (arriving via the vehicle_visual_odometry topic).

The primary height sensor is vision (EKF_HGT_REF = 3).

I would like EKF2 to estimate height using the range sensor as a fallback to the vision sensor. However, I don’t want to fuse it while vision is valid.

(that is, once vision sensor becomes invalid, switch to range sensor, but don’t fuse both).

Is such a thing possible?

I see that EKF2_RNG_CTRL allows turning on aiding from range sensor, but I’m assuming that it fuses also when primary height source (vision) works?