US Patent 9989353 Registering of a scene disintegrating into clusters with position tracking

A method for optically scanning and measuring a scene by a laser scanner includes generating multiple scans; tracking scanner positions with a position-tracking device for the multiple scans and providing tracked scanner positions in response; registering sequentially scans selected from the multiple scans into clusters using registration points or targets and confirming registration of the scans into the clusters according to specified quality criteria being fulfilled; selecting scans from the clusters and forming pairs of scans; forming an intersection of the selected pairs and comparing a size of the intersection with a threshold value obtained based at least in part on the tracked scanner positions; and attempting to register the pairs of scans if the size of the intersection exceeds the threshold value and accepting the registered pairs of scans if the registration is successful.