Building a space occupancy model for a power-line maintenance robot using a range data sensor

A telerobotic system for power-line maintenance is equipped with a laser range-finder allowing it to perform an estimation of its workspace occupancy. This paper describes the model used for describing space occupancy and the 3-D computer vision method developed for extracting this information. It consists in building an octree of the scene from several range images taken from various points of view. A calibration is performed using the first image in order to find the initial position of the camera relative to the scene. Successive 3-D images are used to complete the model information until a satisfying knowledge of the space occupancy is reached.