Excessive Drift in RPLidar S2 Data During Robot Rotation

[miksiWan]

Hi,

We are encountering an issue with excessive drift in the RPLidar S2 data when rotating our robot. During a controlled rotation on its axis, the LiDAR data shows significant and unexpected drift, leading to inaccuracies in localization and mapping.

The robot being used is a differential drive model, and the odometry data is performing well, indicating that the problem is not related to odometry.
To rule out odometry as the cause of the issue, we mounted both a Sick LiDAR and the RPLidar S2 on the same robot and ran them simultaneously. While the Sick LiDAR provided stable and accurate data, the RPLidar S2 exhibited the aforementioned excessive drift under identical conditions.

I believe this is not normal. When using the RPLidar, the robot's localization drifts significantly on a large map. At first glance, I thought the problem was time-related because when the robot stops, the RPLidar data continues to move slightly for a short time before stopping. I can share the bag file if needed

rviz laser topic decay time = 20 seconds

https://youtube.com/shorts/IANQuFX2zf0?feature=share

System Information:

LiDAR Model: RPLidar S2
ROS Version: Ubuntu 22.04 ROS 2 Humble