An Autonomous Running Vehicle Equipped with a Vision System for Fixing and Recognizing Color Landmarks

An experimental autonomous running vehicle with a vision system is developed for load carriers in factories or activity support vehicles of aged or visually impaired people. The vision system extracts color objects of red, yellow, green, or blue in a scene and measures in video-rate the distance and the apparent area of them. By the vision system, the vehicle can recognize color landmarks and obeys the commands assigned to them as well as keeping away from obstacles using four supersonic range meters arranged around the vehicle. In addition, a fixation behavior to color landmarks is realized by a color CCD camera and two stepping mortors to move the camera in horizontal and vertical directions. The running control system is configurated by the Sub-Sumption Architecture which enables us to develop a complicated control system by combining control systems of different behavior. The applicability of the vehicle is demonstrated by several autonomous running experiments to run on the routes specified by color landmarks.