vio drifts a lot when it on stationary situation

[poaongithub]

is there a solution to drifts when the camera stands still?

[k-chaney]

This happens because no features will marginalize and the only update to the filter is from the IMU which is what will cause the drift.

[johnny-wang16]

probably not too related to your question but I found that in some situation, when I choose the start time step that is too close to the actual takeoff time, vio will drift a lot and blow up eventually. but when i start a few frames earlier, it will act perfectly normal. Not sure why this is.

[mildwinter]

I also encountered this problem, it looks like the problem caused by the imu data, but I compared my imu data with the data of MH_03_medium.bag and found no difference. I would like to ask this parameter: Does T_cam_imu refer to the T matrix of imu to cam? Or the opposite?
What do these four parameters mean?
imu_vars / w_var
imu_vars / dbg_var
imu_vars / a_var
  imu_vars / dba_var
Corresponding to acc_w acc_n gyr_w gyr_n?

[johnny-wang16]

Not sure if this will help but I think its worth looking into.
ethz-asl/maplab#54 (comment)