UVM Team Improves Sketch Pad for Blind

Images Can Be Erased, Corrected on New Device

By Tim Johnson
Free Press Staff Writer
August 12, 2009

Instructor Marti Woodman likes to draw graphs for students in the accounting classes she teaches at the University of Vermont. When she wants to modify one of her sketches, though, she faces a challenge most of her faculty colleagues don’t, because she can’t see what she has drawn.

Blind for 7½ years, Woodman makes ample use of tactile sketch pads designed for people with visual impairment. Drawing on such a pad produces a raised line that can be felt by the sightless and seen by the sighted. The trouble is that there’s no way to erase the line once you’ve drawn it on the pad — you have to start from scratch.

Enter students and faculty in UVM’s engineering program. A capstone senior engineering class this past year developed a thermal eraser, an innovation that was demonstrated on a tactile sketch pad last month at the National Federation of the Blind convention in Detroit. UVM developers hope that, after some design modifications, their device will be commercially available.

One selling point, Woodman said, is that the erasable sketch pad is “low technology” — easy to use.

“There are a lot of people going blind who aren’t technically savvy, especially the older population” she said Tuesday, before demonstrating the device. “Also, they don’t know Braille. But they can use a tactile pad to make a list — imagine a grocery list.”

Other applications are likely to be found in art, architecture, education. Erasability would mean, for example, that a blind student working on a math problem could revise an incorrect answer.

A tactile sketch pad brings to mind a child’s toy called “magic slate” — a plastic sheet that adheres lightly to a dark-colored board. You can draw on the sheet and “erase” everything by pulling the sheet off the board.

Similarly, the common tactile sketch pad consists of a plastic sheet on a clipboard. Drawing on the sheet produces raised lines that consist of tiny bubbles. Unlike in the “magic slate,” though, the bubbles don’t disappear when you pull the sheet off the board — the elevated lines are there to stay. If you want to draw something different, you have to use a new sheet.

What the UVM designers devised was a hand-held instrument to get rid of the bubbles — and in effect, to erase the elevated line. The device is a heated stylus that can be dragged along behind a finger that’s moving along the line to be erased.

As engineering faculty members Michael Rosen and Michael Coleman watched, Woodman showed how it works. She drew a face on the pad. Then she traced the line for the chin with one finger and followed it with the stylus. The raised line marking the chin was almost entirely gone.

“Erasing is never perfect,” Rosen said.

The project grew out of SEED (Senior Experience in Engineering Design), a course taught last year by Rosen that puts teams of students to work on yearlong design projects funded by companies or other outside sponsors. The collaborative organization in this case was the National Federation of the Blind.

Students Jon Paquette, Andrew Haas and Jacob Flanagan worked with advisers Rosen and Coleman. They not only developed the thermal eraser, they came up with an improvement in pad design that keeps the sheet taut and flat.

The new pad and eraser were “enthusiastically received” in Detroit, NFB spokesman Christopher S. Danielsen said. “The production of drawings is one of the most significant challenges that blind people face in the course of their educational and professional lives, particularly in science, technology, engineering, and mathematics,” Danielsen said in an e-mail. “Improved technology for producing meaningful tactile drawings will enhance educational and professional opportunities for the blind and allow them to share pictorial information with their sighted peers and colleagues.”

At UVM, the next step is to produce a slimmer version of the stylus and distribute the prototype to about 20 users, Rosen said. Their feedback could lead to further refinements and eventually, he hopes, to commercial production. UVM and the federation would share any revenue.

Meanwhile, Rosen and Coleman are also working on developing a system for transmitting tactile graphics digitally — from one place to another. They’re not ready to say much about that, though.

To Woodson, who has learned Braille but is also able to draw on her visual memory, the tactile sketch pad has another benefit that might not be apparent to a sighted person.

“When I could see, I would see a word like ‘hope’ and get a visceral feeling,” she said. “I don’t get that feeling with the dots in Braille.”

The sketch pad, however, allows her to “see” the written word again and experience that feeling.

Contact Tim Johnson at 660-1808 or tjohnson@bfp.burlingtonfreepress.com.
http://www.burlingtonfreepress.com/article/20090812/NEWS02/90811017