Scan alignment per groups


What you can do if the automatic pre-registration fails?

Here the instance of a set of scans (and/or 3D models) that cannot be aligned because of a low overlap between some scans. 

If it is possible to detect groups of scans already registered and one scan for group that has a good overlap each other, a manual pre-registration can be run. 


A group is a cluster of items composing the project.

A Registration role for all the scans inside the group can be set: None, Same as parent, Children move together. These roles are used to carry out a registration through groups.


The workflow is the following. Letting us help by an example...


  1. Find the groups of scans already registered.

There are two possibilities to create groups:

  1. Automatically

When you automatically register scans  with the LineUp® tool, groups containing just registered scans are created by default

  1. Manually

you can manually create a group already registered scans with the specific command.


In the example below, we indentified two groups: A and B.

We want to move all the scans of the Group B onto the scans of the Group A, without losing the alignment of the scans previously done.  


  1. Apply the “Children move together” registration role to the groups that you want to align. If a single scan is moved in the 3D space, all the other scans move together, as a rigid system.


  1. Find, for each group, a scan with a good overlap with one or more scans in other groups [in the example Scan2(A) and Scan3(B)].
  2. Carry out a manual pre-registration among models to align Scan2(A) and Scan3(B).

Since the “Children move together” registration role of the groups permits a rigid and common movement of all the scans of the groups, this procedure is enough to align all the scans.