Problem with OXTS and transforms

[celynw]

It seems the OXTS poses are being specified as the base_link rather than their dedicated frame imu_link.

kitti2bag/bin/kitti2bag

Line 56 in 06100b0

tf_oxts_transform.child_frame_id = 'base_link'

The KITTI page shows that the GPS and IMU are in the same location.

I believe this may be the problem behind

• The ground truth for visual odometry/SLAM #8
• tf data doesn't seem to exactly match up with gnd truth #11
• What does /tf contain? #12 (comment)

Please let me know if this is correct!

[celynw]

The pull request gives me the behaviour I expect.
I would like it if somebody could verify this is actually correct.
Also, I'd understand if it is denied in favour of a more principled fix.

[J-Rojas]

I believe the TFs that are generated are not correct because the GPS/IMU calibration transform is not applied at all. This static transform would be applied between imu_link and velodyne sensor (which is equivalent to base_link).