Human interface of a robotic travel aid

Robotic Travel Aid (RTA) is a motorised wheel chair equipped with a locomotion system, a multisensor system including vision, sonar and touch sensor, and navigation system including a digital map. It can guide a visually impaired person in the side-walk avoiding obstacles. It has three human interfaces; a commanding bar, a voice maker and Braille key. By touching the command bar he/she feels the motion of RTA and gets mobility and orientation information. When RTA comes near to a crossing or an obstacle it tells him/her the situation through the voice maker. He/she can ask the map information through Braille key