Query regarding alignment

[93won]

Hello, first of all, I'd like to express my gratitude for sharing such a wonderful project.

I have a question regarding alignment.

Below are the ground truth and estimated trajectory files.

stamped_groundtruth.txt
stamped_traj_estimate.txt

When I align the two trajectories using the "-va" command, the result is strangely aligned as follows.

After referring to some questions, I tried aligning with a time offset adjustment as follows:

"evo_ape tum stamped_groundtruth.txt stamped_traj_estimate.txt -va --t_offset 1.6"

In this case, the result was aligned with the top and bottom flipped.

I'm not sure why this is happening.

Would you be able to assist me with this?

Thank you.