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Walking smartly without sight

Recently I started using an ultrasonic walking assistance device, which vibrates when there's an object in front of me. There's a reason for this. I'm blind, and more than before, I'm encountering situations where people walk straight into me, or stand on the tactile paving that I use at stations. Now it doesn't feel safe walking with a white cane alone. Once someone bumped into me, leaving me thinking, "They should have been able to see me from further back." That's when a pedestrian who lent me a hand informed me that the person who walked into me was looking at their smartphone at the time.

    I ended up buying a Palmsonar device made by Yokohama-based Take's Corp, which emits an ultrasonic beam to detect surrounding objects. It fits into the palm of the hand, measuring 77 millimeters in length, 31 millimeters in width and is 20 millimeters in thickness. With its coin-type lithium batteries, it weighs 45 grams. The device costs 81,000 yen.

    The length of the Palmsonar beam, which can be set in seven stages, ranges from 40 centimeters to 4 meters. During the peak commuting time at train stations, I set the distance to 70 centimeters, and on shopping streets, where a lot of people park their bicycles, I set it at 2 meters. What I found interesting was that when lining up at burger restaurants and other establishments and while waiting for traffic lights, when the people in front of me move, the device stops vibrating, so I know I can move forward.

    When you get used to the device, they say, you can even find seats on trains with it. It can apparently detect long objects just 2 millimeters in diameter. On station platforms, not only can it detect people, but it finds the pillars that stand alongside tactile paving. When an obstacle looms right in front of you, the vibration will quicken, regardless of the setting, making it easier to avoid danger.

    The development of ultrasonic assistance devices apparently goes back 40 years to New Zealand. Echolocation, a process by which bats emit ultrasonic waves to detect obstacles and prey, was used to develop equipment. Ultrasonic waves reflected back from other objects were converted into an audible sound, with the transmitter and receiver built into a pair of glasses.

    The Palmsonar, which uses vibrations instead, is particularly handy on station platforms where there is a lot of background noise, including from trains. It's important to protect myself, of course, but more than that, there could be irreparable damage if I accidentally knocked a child or someone else onto the station tracks.

    However, there remains an issue with the Palmsonar. Because I use it together with my white cane, during rainy weather when I'm holding an umbrella, and when I'm carrying shopping bags, I can't use the device. But I have an idea. Could we create a wearable device? A device in the form of glasses, for example, would allow users to detect objects in the direction they are facing. How about it? (By Yasushi Iwashita, Mainichi Shimbun)


    Yasushi Iwashita, 53, is a blind reporter who lost sight in both of his eyes at the age of 10. He joined The Mainichi Newspapers in 1986, and worked in the Braille Mainichi Department. Since 1998, he has put out an online column on the theme "universal design," focusing on people-friendly social mechanisms.

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