EMPIRICAL STUDY ON USABILITY OF CROSSING SUPPORT SYSTEM FOR VISUALLY DISABLED AT SIGNALIZED INTERSECTION

Abstract

 This paper evaluates the adjustment process for crossing support system for visually disabled at signalized intersections with the use of pedestrian traffic signals in concert with visible light communication (VLC) technology through outdoor experiments. As for the experiments, we put a blindfold on sighted people by eye mask in order to analyze the behavior of acquired visually disabled. And we used a full-scale crosswalk which is taking into consideration the crossing slope, the bumps at the edge of a crosswalk between the roadway and the sidewalkand crosswalk line.
 From the results of the survey, it is found that repetitive use of the VLC system decreased the number of lost their bearings completely and ended up standing immobile and reduced the crossing time for each person. On the other hand, it is shown that the performance of our VLC system is nearly equal to the existing support system from the view point of crossing time and the number of standing immobile and we clarified the effect factor for guidance accuracy by the regression analyses. Then we broke test subjects down into patterns by cluster analysis, and explained the walking characteristics for each group as they used the VLC system. In addition, we conducted the additional surveys for the quasi-blind subjects who had difficulty walking by using VLC system and visually impaired users. As a result, it is revealed that guidance accuracy was improved by providing the information about their receiving movement at several points on crosswalk and the habit of their walks for each user.