@shawn_ricardo Hi!
To my understanding EKF2_EV_CTRL 15-->13 only remove EV from pos_z estimation, so it should be ok to do that if the range sensor is active. However, I did revert all parameters to the default settings (matching the VOXL-SDK definitions).
As my attempts to integrate the range-sensor data in altitude estimation did not seem to succeed, I decided to try and integrate the range-sensor in the VIO solution.
I created a version of the voxl-qvio-server in which pos_z estimation from VIO is replaced by the equivalent value based on the rangefinder:
s.T_imu_wrt_vio[2] = - down_range_m;
This seem to work better, however it is a workaround and not a full solution. My current experiments are performed in low altitude (~40-90 cm), so I am not concerned with the limited range of the rangefinder sensor.
I'm not sure what is the current implemented behaviour when EV estimation is not good, there should be some fall-back relying on the range sensor and imu. From my short experience with such cases of poor EV estimation mid-flight, the drone just crushes or jump to the ceiling with no control.
Any suggestions or further explanations will be much appreciated. Thank you