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SJTU-ViSYS / M2DGR

M2DGR： a Multi-modal and Multi-scenario Dataset for Ground Robots(RA-L2021 & ICRA2022)
MIT License
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Velodyne points have negative time stamps? #87

Closed brytsknguyen closed 5 months ago

brytsknguyen commented 9 months ago

Hi

I suppose the correct pcl definition for the pointcloud would be as follows: https://github.com/TixiaoShan/LVI-SAM/blob/0d822f6dcac3378312f6703b4f45829e049f221a/src/lidar_odometry/imageProjection.cpp#L5

When I print out the time stamp of the points, their values are negative: image

This is a little bit surprising since I mostly encounter data with positive timestamps of the points.

Should the timestamp be the actual offset from pointcloud2 msg timestamp?

sjtuyinjie commented 5 months ago

Thanks for answering.