The task of registering three dimensional data sets with rigid motions is a fundamental problem in many areas as computer vision, medical images, mobile robotic, arising whenever two or more 3D data sets must be aligned in a common coordinate system. In this paper we make a study of registration methods for egomotion calculation on robotics. We are interested in determining which is the best method to apply depending on execution time and accuracy. We have selected two of the most used methods: Iterative Closest Point (ICP) and Ransac (with visual features), and we have developed a fast implementation of ICP in the GPU. Several experiments have been done in order to determine which method must be select depending of the input data.