Simultaneous mobile robot positioning and LPS self-calibration in a smart space

This paper presents a new algorithm that allows the simultaneous positioning of a mobile robot and the self-calibration of an ultrasonic-based LPS (Local Positioning System). The system integrates the data obtained by the on-board dead reckoning (relative positioning) and the measurements from the beacons that constitute the LPS (absolute positioning), using an H-∞ filter. At the beginning of the process the dead reckoning is used for both, robot localization and LPS auto-calibration and after a predetermined time the system uses the LPS information to correct the positioning obtained with the dead reckoning (that is affected by a cumulative error as the position is calculated integrating the axis velocities in the robot). The formulation of the algorithm and the results obtained with some particular trajectories of the mobile robot in the coverage area of the LPS are presented.