External Vision in the EKF2 Critical Navigation Failure


I’m working on integrating an external vision sensor into the EKF2 on PX4 version 1.8.0. We have previously been flying with great success on the inav/attq combo. I’ve been having issues flying indoors with the EKF2 under external vision estimation (no gps).

During manual flights, I keep getting a CRITICAL NAVIGATION FAILURE - CHECK SENSOR CALIBRATION message from commander, while the EKF2 position estimate seems to hang.

Here is an example flight that exhibits the issue: https://logs.px4.io/plot_app?log=7d81671f-c98a-4250-9293-58587f24818d

I feel like I’m missing something silly, do you guys have any thoughts?


I’ll be updating this post as I learn about the problem.

I discovered that despite mavlink requiring me to send in a position estimate covariance as part of the message, the mavlink receiver is not configured to unpack it. It looks like this has been updated on master.

Is it more common to use the local_position_ned_cov + attitude_quaternion_cov for these applications instead?