I created a video for a customer to illustrate proper loop closure techniques and I thought it would be nice to share.
Enjoy!
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If you are aligning to GCPs in the field, say in a linear environment, do you still need loop closure?
@wallsLANDwater not necessarily. It just depends on how many GCPs you have. Loop closure is just a good way to do cloud to cloud registration and eliminate the need for so many GCPs.
Hi Alex, I did watch the movie. I have a four floor hotel from 1887 that is currently gutted and BIM needs interior scans on each floor to relocate stairs and elevator. I can do three similarly sized loops per floor and each floor looks good on its own however if all done in same SLAM session it looks like the Haunted Mansion at Disney World see attached image.
I am going to retry floors individual SLAM sessions with two gcps on each floor all shot from one exterior control point to tie the four point clouds together.
I suspect the problem is that there is only one central staircase in which to “loop” in the vertical plane, the 4 pair gcps should remove this variable.
Finally my question is did this vertical loop problem come up during the Stanford session? If not was it due to the numerous stairwells in modern fire code?
Thanks
@patriotlands you are correct to think the stairwells are the likely cause of the problem. If you can get 4 gcps per floor and use them in Rock Desktop, that would be best.