Today, blind people fluent in Braille can read computer screens through refreshable mechanical displays that convert the words to raised dots – but only one line at a time.
For the sighted, imagine a Kindle that showed just 40 characters per page, says Sile O’Modhrain, an associate professor in the University of Michigan School of Music, Theatre and Dance and the School of Information, who is blind. Forty characters amounts to about 10 words.
The process is cumbersome. It doesn’t give context. It’s expensive. And O’Modhrain believes it’s one of the factors contributing to Braille’s declining use. Even though fluency in the nearly 200-year-old code is linked with higher employment and academic performance for the visually impaired, fewer blind people are learning and using it. Taking Braille’s place are text-to-speech programs that make it easier and faster to consume electronic information, but at the same time, hold back literacy.
So O’Modhrain has teamed up with engineering researchers to build a better Braille display – one that could show the equivalent of a whole tablet screen at once. In addition, it could translate beyond text, rendering graphs, charts, maps and complicated equations in a medium the blind could understand with their fingertips.
“What we’re trying to build in this project is full-page tactile screen for something like a Kindle or an iPad where you could just display refreshable text in real time,” O’Modhrain said. “Relative to what’s done today and how that’s done, it’s a complete paradigm shift.”
In the 1950s, about half of blind children learned to read Braille, according to the National Federation of the Blind. Today, that number is just 10 percent. Yet 80 percent of blind people who are employed know Braille. Those numbers don’t tell the whole story, as definitions and health outcomes have evolved over the years. But the trend they suggest is real, the researchers say.
“When you’re learning to read and write, it’s hard to find a substitute for physically encountering text – whether it’s in visual or tactile form,” O’Modhrain said. “There are many studies that show that listening to something is not the same as reading it.”
The system she is developing with Brent Gillespie, an associate professor of mechanical engineering, and Alex Russomanno, a doctoral student in the same department, would make e-reading for the blind more efficient and a lot less expensive. Today, a commercial one-line Braille display costs around $5,000. If you were to directly scale up the mechanism behind it to show a whole page, it would cost around $50,000, Russomanno says. The U-M researchers’ aim to offer that capability at just $1,000 per device.
How can they make a bigger display at a fraction of the cost? They believe the answer is microfluidics – a branch of engineering centered on tiny chips with channels that guide the flow of liquid or air. In many ways, microfluidic chips resemble the integrated circuits of computers.
“We use the equivalent of electronic logic and circuitry,” Russomanno said. “When I say that, I’m referring to the way a computer works, with transistors and resistors. Except our circuit is not electronic at all. It’s fluidic. Instead of high voltage and low voltage you have high pressure and low pressure, and instead of electric current flow you have fluid flow and you can achieve the same basic logic features.”
Like the 0s and 1s that undergird computing, Braille is a binary code. Each Braille cell, which is sometimes a letter and sometimes a whole word, contains six dots that can either be raised or flat to convey different information.
“The dots are either there or they’re not,” O’Modhrain said. “That’s why this circuit is so elegant.”
Their system uses air to move bubbles of pressurized air that raise or lower the Braille dots. And whereas other approaches require a dedicated information channel for each dot, theirs can control a long string of dots with just two input valves. The length of the dot string is limited only by the time it takes the information (high or low pressure/raised or lowered dot) to get to its end point.
There’s also overlap in the manufacturing processes of electronic and fluidic circuits. Microchips are made all at once, rather than transistor-by-transistor. In the same way, the researchers can mold as many Braille dots as they like with one batch process. They say this will be key to economically making a full-page display.
Right now they’re working on shrinking their fluidic circuits to fit under Braille dots, which would be smaller than a peppercorn. They envision a system where up to 10,000 dots are powered by 10,000 microfluidic chips.
“We would like to think a device like this would make reading electronic Braille more attractive again, make it close to the experience of reading a traditional book,” O’Modhrain said. “Another challenge is convincing educational authorities to teach Braille again. It has dropped out of the system in terms of the education of blind people and we think it’s important to bring Braille back.”
About Michigan Engineering: The University of Michigan College of Engineering is one of the top engineering schools in the country. Eight academic departments are ranked in the nation’s top 10 — some twice for different programs. Its research budget is one of the largest of any public university. Its faculty and students are making a difference at the frontiers of fields as diverse as nanotechnology, sustainability, healthcare, national security and robotics. They are involved in spacecraft missions across the solar system, and have developed partnerships with automotive industry leaders to transform transportation. Its entrepreneurial culture encourages faculty and students alike to move their innovations beyond the laboratory and into the real world to benefit society. Its alumni base of nearly 70,000 spans the globe.
Source: Article by Nicole Casal Moore, Michigan Engineering, University of Michigan.