Severe distortion of point clouds observed by Livox mid360

[YinghaoJia98]

When I use Livox mid360 and VLP-16, Ouster-64 to simultaneously face the same flat wall, the point cloud observed by Mid360 is a point cloud with severe curvature distortion, which is significantly different from the other two point clouds. This is not the case when using Livox avia. I don't know if there is a problem with my configuration.

[YinghaoJia98]

当我使用Livox mid360和VLP-16，Ouster-64同时面对同一面平整的墙壁时，Mid360观测到的点云是有弧度的失真严重的点云，和其他两个点云对比明显。当使用Livox avia时则没有这种情况。不知道是不是我哪里配置有问题。

[georgflick]

maybe your issue is related to https://github.com/Livox-SDK/livox_laser_simulation/issues/3 ?

[YinghaoJia98]

Here is the topview picture. The red point cloud is given by OUSTER-64 while the white is given by Livox Mid360. The red one can be seen as the true value. @georgflick

[john-maidbot]

Thank you @georgflick ! I had this same problem (with the mid360) and setting the min ray length to 0.0 worked for me. in my case, i did this by setting this line to "0.0" rather than the min range value when generating the multiray shapes: https://github.com/Livox-SDK/livox_laser_simulation/blob/1cce1073633a062b92e30243a4c2920e45551bb5/src/livox_points_plugin.cpp#L94

that way the collision checking is not warped, but a user can still set the min laser range via the urdf and have that be respected.

[YinghaoJia98]

@georgflick Thanks for your help!