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TixiaoShan / LIO-SAM

LIO-SAM: Tightly-coupled Lidar Inertial Odometry via Smoothing and Mapping
BSD 3-Clause "New" or "Revised" License
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processing 2 time stamps old point cloud #458

Open huzefablue opened 11 months ago

huzefablue commented 11 months ago

In imageProjection.cpp in the cachePointCloud() function, at the very start, the cloudQueue is not processed till it has 2 elements. And after that is processes the oldest element in time in the queue. Wouldn't this cause the odometry to always be outdated by two timestamps?

ghost commented 10 months ago

If the pose you accept comes from "lio_sam/odomTopic" in the yaml format configuration file, then its timestamp is almost current, because the function "IMUPreintegration::imuHandler" integrates it in real time and sends it out with this topic. Of course, the imu's bias is two timestamps behind, but it doesn't matter. I think setting the cloudQueue cache size to 0 will not affect the operation.

Sonne-Zhu commented 5 months ago

Set the cloudQueue cache size to 0 will lead bad result, why？