A relative motion estimation by combining laser measurement and sensor based control

Abstract

A pose estimation method applied to an indoor mobile robot equipped with a laser range-finder that periodically delivers a range scan of the environment is presented. The method is based on the fusion between the range readings delivered by the laser and the feedback control input computed to constrain the robot to move in its free workspace. The relative motion of the robot between two successive sampling times of the control loop is estimated:(1) computing a prediction by comparing the local maps built at these instants, (2) integrating the feedback control input computed from the laser readings to produce the desired motion and (3) performing a fusion between these two predictions. These computations are performed at sampling rate during the robot's evolution and are embedded in a probabilistic approach taking into account the uncertainties associated to the laser readings. Experimental results are presented validating the proposed method.