The autonomous mobile robot SENARIO: a sensor aided intelligent navigation system for powered wheelchairs. - Nikos I. Katevas; Nikitas M. Sgouros; Spyros G. Tzafestas; George K. Papakonstantinou; Paul D. Beattie; John Mark Bishop; Panayotis Tsanakas; Dimitrios Dionisios Koutsouris (IEEE Robotics Autom. Mag., 1997)