Scanning Corridors and Tunnels
In some cases, especially when scanning corridors and tunnels there might be a lack of features to which SLAM system can match the points and register the data correctly. Usually this happens when the corridor or a tunnel looks exactly the same throughout all of the area of the scan.
If the corridor, tunnel or a similar environment does not contain any distinct features, some features need to be placed tin the direction of travel to prevent SLAM from slipping. This helps the SLAM algorithm find relatable features and therefore positions the scan data correctly.
Place boxes, tables, chairs or any other distinct objects in the area of interest
- Be larger than 1m in length, height and depth
- Be at a maximum distance of 10m from other distinct objects
Be aware of limited range due to angle of incidence (demonstrated in the animation)
When walking through corridors, the further the scan line, the less points there are. As well the inclination angle becomes smaller further, which makes it harder for SLAM to have confident points.
Adding features in case like this helps to position the points and trajectory with more confidence.