Novel PCSE-based approach of inclined structures geometry analysis on the example of the Leaning Tower of Pisa

Abstract

The study develops the Point Cloud Spatial Expansion (PCSE) method by introducing the procedure of verticalization of point clouds. The inclined axis of a sloped symmetrical object causes distortions in the PCSE datasets, and its content is inconsistent with the actual state of the structure. By using the Errors-In-Variables estimation, the course of the inclined axis of symmetry of the object is determined. The processed data set ensures the correct results of the PCSE method. The practical verification of the algorithm was carried out on a point cloud of one of the most characteristic inclined buildings in the world – the Leaning Tower of Pisa (Italy). The study proved the validity of introducing the point cloud verticalization procedure in the PCSE, which resulted in gaining additional features of universality and efficiency of the method.