Research of Operation Method of Accessibility Equipment for Severely Handicapped Based on Voluntary Eye Blink

Abstract

Serious disabled persons with motor disabilities such as amyotrophic lateral sclerosis and progressive speech impairment necessitates the use of an assistive communication aid. However, the disabled also need accessibility equipment to use the aids. This paper describes the research of the input method for the operation of the accessibility equipment, which is used by the serious disabled. The input method is based on electro-oculo-gram (EOG) that is controlled by the disabled. EOG is a technique for recording eye movements and eye blinks through electrodes placed around the eye. If the disabled can create several patterns of EOG waveforms, multiinput method is realized using these differences. We previously reported the technique to identify voluntary eye blink appeared on the EOG. Because voluntary eye blink is simple operation, we investigate the possibilities of utilization of consecutive blinks and gaze. 1) We examined the influences of the consecutive voluntary eye blinks by changing the blink intervals. We revealed that the blinks in interval at <300 milliseconds generate a unique waveform of EOG. 2) Because it is possible to specify the point of gaze with rough accuracy by EOG, we also investigated if specifying approximate gaze positions could make different EOG. The gaze positions results showed that the blink-evoked EOG waveforms were extracted at a reliability >95% when incorporating upward gaze and forward gaze. The results suggest that the incorporation of upward gaze and forward gaze has possibilities of realization of multi-input method.KeywordsAccessibility EquipmentElectro-oculo-gram (EOG)Voluntary eye blink