Non-visual traffic signal information: An investigation of the recognition performance of blind users using the wearable tactile traffic lights assist device

Abstract

Visually impaired people face numerous obstacles and troubles in their daily life. In particular, safely crossing the road is an obvious problem. In this study, a wearable tactile traffic lights assistive device (WTTLAD) was designed for visually impaired people, and its effectiveness was verified through a performance experimental design. We recruited visually impaired and blindfolded sighted subjects to test the WTTLAD. The subjects' performance was investigated in two experimental fields: in a laboratory (indoor field) and at a road intersection (outdoor field). The results show that the tactile recognition performance of the visually impaired subjects was higher than that of their blindfolded counterparts for the WTTLAD. The correct recognition rate did not differ significantly between the visually impaired and blindfolded sighted subjects in the indoor field. By contrast, a significant difference was observed in the outdoor field. Overall, the visually impaired subjects attained more stable performance than the blindfolded sighted subjects did in the outdoor experimental field, and their average correct recognition rate reached 96.67%. The results indicate that the blindfolded subjects were more likely to be disturbed by preexisting visual experiences and environmental noise. The tactile working memory of the visually impaired subjects was a crux on the preponderance of their tactile recognition performance. We anticipate enhancing the safety and reliability of visually impaired people by promoting the proposed device to assist them with crossing road intersections.