EKF fuses vision data, but drifts and ignores vision in around a minute

PX4 Autopilot
1

Using an external vision sensor (HTC Vive) to provide position estimate to pixhawk EKF2.
The EKF fuses the vision information for a few tens of seconds, but the estimate starts drifting and resets to the x=y=~0 origin.
The logs of a test are here: https://logs.px4.io/plot_app?log=f16ec023-ecad-43cc-975e-2e7bfaf7deca .
The specific test sequence was
Pitch up once
Roll right thrice
Yaw right 4 times.

A video of Rviz can also be here: https://streamable.com/m1201

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@Paul_Riseborough Is this something you can comment on?

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Any help on how to debug this ?

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There has been quite some progress on the external vision pose estimate fusion. If you are still interested you can give current master a try.

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It could be from the high lag between the vision to pixhawk delay (~300ms). Changing this param to zero removed this issue.
So we changed few things on our system to reducing the lag to under 100ms resolved this issue.

1 Like
6

Some closure on this:
This was since the ground station PC and the onboard raspberry pi were not time synced. When they were synced, the problem of drift vanished.