Electric wheelchair control with gaze direction and eye blinking

Abstract

We propose an electric wheelchair controlled by gaze direction and eye blinking. A camera is set up in front of a wheelchair user to capture image information. The sequential captured image is interpreted to obtain the gaze direction and eye blinking properties. The gaze direction is expressed by the horizontal angle of the gaze, and this is derived from the triangle formed by the centers of the eyes and the nose. The gaze direction and eye blinking are used to provide direction and timing commands, respectively. The direction command relates to the direction of movement of the electric wheelchair, and the timing command relates to the time when the wheelchair should move. The timing command with an eye blinking mechanism is designed to generate ready, backward movement, and stop commands for the electric wheelchair. Furthermore, to move at a certain velocity, the electric wheelchair also receives a velocity command as well as the direction and timing commands. The disturbance observer-based control system is used to control the direction and velocity. For safety purposes, an emergency stop is generated when the electric wheelchair user does not focus their gaze consistently in any direction for a specifi ed time. A number of simulations and experiments were conducted with the electric wheelchair in a laboratory environment.