Illuminant effect on LCD and LED stimulators for P300-based brain-controlled wheelchair

Abstract

The proposed study aims to investigate the illuminant effect of P300 visual stimulation for brain controlled wheelchair. According to practical usage, the wheelchair might go in various locations which have different illuminance. Sometimes, user is unable to perform their command due to visual interference by external illuminant effect. Therefore, in this study, we have setup three environments; quite dark room (5-10 lux, EN1), normal room (300-400 lux, EN2) and bright room/corridor (700-900 lux, EN3) for investigating an effect of accuracy and characteristic of P300 potential. Another study is the comparison between two different stimulators (the new LED and traditional LCD screen stimulator) among three environments. The results show that LED stimulator gives higher accuracy and higher total area under N200 and P300 components than that of LCD stimulator in all three environments. Both accuracy and total area are decreased when illuminance is increased. The highest average accuracy (96.87%) is occurred in EN1 by LED stimulation. However, LCD screen stimulator is friendly to the user's eyes while LED stimulator usually lead to the eye fatigue. For brain controlled wheelchair application, we suggest to use LED stimulator for outdoor environment (EN3) and LCD stimulator for EN1 and EN2 to prevent the eye fatigue. © 2011 IEEE.