How accurately people can discriminate the differences of floor materials with various elasticities

Tactile ground surface indicators installed on sidewalks help visually impaired people walk safely. However, these indicators sometimes cause the nonvisually impaired to stumble. Thus, these indicators also have to be made safer and less of a problem for those who do not use them. There are several facilities in Japan that have installed floor materials of different elasticity to indicate paths for the visually impaired. However, the effectiveness of this method has not been tested. Therefore, this study examined how accurately people can discriminate differences in the elasticity of flooring samples. Flooring samples of different elasticity were presented by placing two walking boards made of plywood, each surfaced with one of three different flooring samples, in an end-to-end fashion. Ten young adults whose sight was temporarily cutoff by eye masks were asked to walk on the path for 144 trials and indicate whether the flooring samples were different or not. Interestingly, the percentages of correct answers were high for most pairs of samples. Moreover, there was a strong positive correlation between the percentage of correct answers and the magnitude of difference in floor elasticity. These results indicate that people can distinguish changes of flooring samples fairly accurately, even when there are no convexities, if there is sufficient difference in elasticity between the flooring samples.