Collision avoidance by observing pedestrians´ faces for intelligent wheelchairs

With the increase in the number of senior citizens, there is a growing demand for human-friendly wheelchairs as mobility aids. One of the main issues in the robotic wheelchair research is autonomous obstacle avoidance for safety. However, this is difficult because most moving obstacles in the real world are human beings. They sometimes change their motion abruptly. The paper presents an intelligent wheelchair that can avoid collisions with such human pedestrians safely and comfortably for each other. We assume that the information whether or not a pedestrian has noticed the wheelchair and which direction he/she wants to go can appear in the face direction. Thus our intelligent wheelchair is continuously observing the pedestrian´s face in its front area, realizing smooth passing by changing its collision avoidance strategy based on the face information and the range data from the ultrasonic sensors. Experimental results show the effectiveness and comfortableness of the proposed method