Sphere Target Fitting of Point Cloud Data Based on TLS

摘要

Sphere target is an important toolbox in terrestrial laser scanning. With the sphere target, multiple point clouds data obtained from different views can be transformed into the same coordinate frame. Determination of the sphere target center is key to complete the task mentioned above. A usual approach to determine the coordinates of the center of the sphere is the Less Squares (LS) method. In this paper, a new method using Total Least Squares (TLS) to determine the center of the sphere target is investigated. For the new method, a special model is assumed that the design matrix contains the linearization, and errors in both the residuals vector and the design matrix can be minimized simultaneously. Various experiments are conducted using the real point clouds data, and it is shown that the proposed TLS approach works effectively and achieves better results than the usual LS method.