Dr. Masaki Tauchi and his colleagues are involved in exciting research regarding people who are blind or have other disabilities. This page shows photos from a tour of the university labs, and an experience at a tactile guide strip in a crosswalk. Click here for related text from the Diary from Asia.
Detectable and navigable surfaces
Surfaces that are tactile and detectable to blind people can cause extensive vibrations to people in wheelchairs, bicycles, or strollers. Researchers at the university are trying to determine a surface that is detectable and causes an acceptable level of vibrations.
Below, Dr. Takabun Nakamura lays out various testing surfaces next to a bar which will guide the subjects.
The lab has more than a dozen wheelchairs. The one to the left has sensors to detect vibrations (one in front of each wheel and one by each arm). Professor Nakamura wears a vest designed to measure the amount of vibrations caused by the various surfaces.
Handrails in the lab can be positioned anywhere along the tactile surfaces. The subjects follow the rails and report when they detect a change in surface.
Indication of street edges:
In the U.S., the truncated dome surface is called a “detectable warning surface” and it is used exclusively to indicate that something is just ahead which requires alertness, such as the edge of a street or a train platform. Thus, when people notice the detectable warning surface, they know there is a hazardous edge such as a street very close (at the edge or within inches of the warning surface).
However in Japan and many other countries in Asia, truncated dome surfaces are used to indicate a multitude of things -- not only hazardous areas, but also points of interest such as ticket counters, elevators, entrances, and tactile maps. Blind people in Japan have expressed the need to have something to indicate that they have reached a street. The solution that is being used or considered in Japan is to have a change in surface level at the edge of the street, in addition to the truncated dome surface.
The Okayama Prefectural University is investigating the problem of how to make a change in surface level that is detectable to blind people and yet is not a barrier to people in wheelchairs. Dr. Nakamura demonstrates the site which tests various concrete slopes and edges, to see what is both navigable and detectable. Here, he lays down the tactile bar strip and truncated dome surface along a concrete platform.
Below: The sloped surface under Dr. Nakamura’s foot will be tested by wheelchair users and blind subjects.
Indicating localization of sounds
Traditionally, when testing the ability of people to localize various sounds, researchers will have subjects point to the sound source, or turn their head in its direction while a device on the top of their head indicates how many degrees from straight they have turned. Atsunori Fujii, Assistant Professor at the University, has developed a low-tech technique that allows for more precision in reporting the direction of the sound.
Below: Professor Fujii positions Stephan at the table with tactile lines radiating 5 degrees apart, extending 90 degrees to each side of straight ahead; speakers are positioned in a semi-circle in front of the subject. The radiating tactile lines are made of uncooked spaghetti noodles glued to the table. They are marked to indicate how many degrees from straight they are.
Stephan wears a blindfold and prepares for the test, and points to the line indicating the direction from which he thinks he hears the sound …
… and Professor Fujii notes to which one Stephan is pointing.
Detectable guiding strip for crosswalks
Dr. Masaki Tauchi is experimenting with tactile guide strips. One has been installed along a crosswalk in Okayama, to learn the rate of deterioration of the strip from the tires.
Below: Dr. Tauchi accompanies me as I experiment with the guiding strips. It took some practice to be able to detect them.
