<title>Application of a laser scanner to three-dimensional visual sensing and enhancement tasks</title>

Abstract

This paper describes the issues associated with using a laser scanner for visual sensing and the methods developed by the authors to address them. A laser scanner is a device that controls the direction of a laser beam by deflecting it through a pair of orthogonal mirrors, the orientations of which are specified by a computer. If a calibrated laser scanner is combined with a calibrated camera, it is possible to perform three dimensional sensing by directing the laser at objects within the field of view of the camera. There are several issues associated with using a laser scanner for three dimensional visual sensing that must be addressed in order to use the laser scanner effectively. First, methods are needed to calibrate the laser scanner and estimate three dimensional points. Second, methods are required for locating the laser spot in a cluttered image. Third, mathematical models that predict the laser scanner's performance are necessary in order to enhance three dimensional data. The authors have developed several methods to address each of these and have evaluated these methods to determine how and when they should be applied. The theoretical development, implementation, and preliminary results when used in a dual arm eighteen degree of freedom robotic system for space assembly is described.