Image copyright Eone Image caption The ball bearing on the front tells the minutes

The Bradley Timepiece, a watch designed for blind people and named after a Paralympian gold medallist who lost his sight in Afghanistan, is up for design of the year at London's Design Museum. But it's mostly being bought by sighted people, writes Chris Stokel-Walker.

The watch has a stark, circular titanium face. There are no hands. There are no numbers. Around a groove in the centre a ball-bearing rotates to mark the minutes. Around the edge of the watch, another ball bearing rotates to tell the hours.

The Bradley was designed for the use of blind people, the latest in a long line of efforts to help those without sight efficiently tell the time.

Designer Hyungsoo Kim was in a lecture hall at Massachusetts Institute of Technology in September 2011 when a neighbouring student asked him the time. "My classmate is visually impaired, and had been for 10 years," explains Kim.

The student had a watch that could tell the time, but only by pressing a button that would make it speak out loud. Doing so in a classroom could be disruptive, so instead, says Kim, "I was his wristwatch."

Image copyright Eone Image caption The ball bearing on the side tells the hours

There are a number of timepieces for the blind, including the Meteor vibrating watch that uses a series of rumbles to denote hours and minutes. Tactile, or Braille watches, are popular in the blind and partially sighted community. They look similar to a normal watch, but the front glass can be flipped up, allowing the wearer to touch the hands and tell the time.

"If you're blind you don't know if you've got up in the middle of the night," explains Leslie Duroe of RNIB, the UK's main charity for the blind and partially sighted. "It can make people feel very insecure to not know what time it is."

For Kim, previous designs were more functional than beautiful. Sighted people choose their watches as much as a fashion statement as for merely telling the time. Many might assume that blind people care only about function. But that's wrong.

There were also practical criticisms over existing watches for some users - in the case of tactile or Braille watches, foreign objects such as food could clog or affect the progress of the hands.

Image copyright RNIB Image caption The RNIB already stocks a range of timepieces for the blind, including the Meteor

Kim wanted a watch that looked good and would work for his friend.

"I put together a team of engineers and we came up with the idea of a Braille display, one that would display the time written out in Braille," says Kim. But when a prototype was created, the feedback wasn't great.

"We learned that less than 10% of visually impaired people can read Braille," Kim says. What's more, many people in the UK and US are not born blind but develop sight problems later in their lives - 82% of those living with blindness are aged 50 or older, according to the World Health Organization.

With less experience of reading Braille, their sense of touch is often less developed.

Kim and his team went back to the drawing board - the timepiece went through 25 different versions, each one tested by visually impaired people.

There was always a battle between functionality and producing a beautiful object.

A user's guide to 'blind' watches Damon Rose is blind, and produces the BBC's Ouch disability podcast and blog - he describes the pros and cons of timepieces currently on sale for blind and partially-sighted people: "Telling the time if you're blind is a question of 'tactile v talking'. A discreet feel of your Braille watch under the desk, allows you to know if a meeting is going on too long or if it's lunchtime. Unfortunately, touching the button on a talking watch, broadcasts the time to the whole room and rudely suggests, 'I want to be somewhere else.' And in the middle of the night can wake your partner unless you stifle it with a pillow. "Braille watches present other problems - you have to probe gently for fear of knocking the hands and altering the time. And if you want to check your watch during dinner, beware of getting food inside it. "Manufacturers of accessible goods for blind people have discovered that producing something functional isn't enough - blind people always ask what it looks like, even though they can't see. In some ways, this suggests that it matters more if you're trying to control what people might think of you." BBC News - Ouch

Eventually, a design was agreed upon - a magnet underneath the metal watch face would control two rotating ball bearings for hours and minutes. But even the ball bearings were a matter of debate.

"People wanted the ball bearings to be bigger so they could feel it better," Kim says. "But as designers, were concerned that making them bigger would make the watch clunky. We had to find the midpoint."

In September 2011, the same month Hyungsoo Kim started work on his project, life changed for bomb disposal officer Lieutenant Bradley Snyder. He stood on an explosive device in Afghanistan, suffering serious injuries and losing his sight.

By August 2012, he had won two swimming gold medals at the London Paralympic games. But the practicalities of daily life were initially an immense struggle.

"I was hurt in Afghanistan and the next thing I know I'm waking up in hospital in the United States. There was a 60 hour-long gap in my memory."

Immediately Snyder, his sight lost, found getting his bearings difficult. "You don't realise how much you use time to orient where you are. At the beginning it was very disorienting. And especially being in the military, time is all important."

Image copyright Getty Images Image caption Bradley Snyder won two gold medals in the London 2012 Paralympics

Eventually Snyder was approached by Kim, after a chance meeting with a mutual friend. "Hyungsoo was making a product for blind people," says Snyder. "I was his blind guy."

"I had a speaking watch for a little while," he begins. "You pressed a button and it told you the time." Uncannily mimicking a robotic voice, Snyder says "the time is 3:30pm" and laughs. "It was utilitarian. And if I'm on a train, I can't hear it.

More from the Magazine Image copyright Other Fashionable brands have long dominated the sportswear market, but up to now few have specifically targeted disability sports. Nike has now become the first to produce a sole for a blade used by amputee runners. Has the era of Paralympic chic dawned? Nike launches the era of Paralympic chic (February 2012)

"What's more, as soon as I hit that button it highlights me as someone with a special need. I love the idea of using the same thing that everyone does. And I want to feel as normal as possible."

With the watch now named the Bradley, there was an appeal on Kickstarter, the crowdfunding website, in July last year - 3,681 people from 65 different countries backed the project, donating a total of $594,602 (£357,290). It will be available for sale from May in the US, with the UK and Europe likely to follow later.

A further 1,000 people have since pre-ordered the watch online but only a tiny fraction of those - Kim estimates between 1-2% - are visually impaired.

"It bridges the gap between the disabled and the non-disabled," says Snyder.

The watch is now among the favourites in the 76 nominations for the Designs of the Year contest at London's Design Museum. The nomination has already led to interest from European retailers. There's an obvious gimmick for selling to sighted people - you can check the time in a social or work setting without appearing rude.

It's easy to imagine seeing the watch, with its titanium face and minimal style, on a wrist and not immediately guessing its genesis as an item for blind people.

"The stereotype is that visually impaired people are not fashion-conscious," says Kim. "I had that misconception too. But it's wrong."

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