# Revision history [back]

### Removing 3D LIDAR 'rings' from pointcloud for ground estimate?

Hi,

I am fairly new to pointcloud filtering but have done some research and found that the best method for ground estimate in pointcloud data is by removing the lidar rings. I have run a pcl::SampleConsensusModelSphere model through RANSAC to estimate the ground and am finding that between my data sets occasionally it will detect walls and occasionally the actual ground. The robot will be operating on hilly terrain. Is there perhaps a better model to model these rings, or perhaps there is a way to pre filter the data to remove walls?

All help is appreciated :) thanks.