MOBILE ROBOT LOCALIZATION BY TRACKING GEOMETRIC BEACONS

This short paper presents the application of the extended Kalman filter (EKF) to the problem of mobile robot navigation in a known environment. We have developed an algorithm for model-based localization that relies on the concept of a geometric beacon-a naturally occurring environment feature that can be reliably observed in successive sensor measurements and can be accurately described in terms of a concise geometric parameterization. The algorithm is based on an EKF that utilizes matches between observed geometric beacons and an a priori map of beacon locations. We describe two implementations of this navigation algorithm, both of which use sonar. The first implementation uses a simple vehicle with point kinematics equipped with a single rotating sonar. The second implementation uses a "Robuter" mobile robot and employs six static sonar transducers to provide localization information while the vehicle moves at typical speeds of 30 cm/s.