SEMI AUTOMATIC REGISTRATION OF LASER SCANNER DATA

Abstract

Laserscanning is a technique that is becoming very popular for the acquisition of 3D models, especially in industrial environments. As industrial sites are in many cases complex environments, scans from multiple viewpoints have to be taken to be able to model the entire site. Before modelling the site can start, registration of all the scans is required. This paper discusses the semi automatic registration of laser scanner data. Starting point for the registration are object models measured in two scans taken from different positions. The fitting algorithms to find the parameters of the models are based on non-linear least square adjustments. The method used is not bound to the fitting of a particular model but can be used for different kind of models. The parameters are estimated from the distances from the points to the model. As the equations are non-linear initial values for the parameters are needed. A method to find these for cylinders and planes is discussed. Based on the parameters of the models measured in different scans the registration is performed. Assuming neighbouring laser scans to be taken from one sit of an object no approximated values are needed.