[tabi] Re: Braille Displays Promise to Deliver the Web
- From: "Darla J. Rogers" <djrogers0628@xxxxxxxxxxx>
- To: <tabi@xxxxxxxxxxxxx>
- Date: Sat, 1 May 2010 16:01:30 -0400
I'm writing to them to see if they need beta testers.
Darla, A proud Braille reader
Darla J. Rogers, B.A. Social Science; M.S. Rehabilitation Counselor Education
djrogers0628@xxxxxxxxxxx
Home phone #: 850-329-7437
Cell #: 850-443-3571
Skype ID: wildflower0628
I suited up for the long walk back to myself...
....Ani DiFranco
----- Original Message -----
From: Lynn Evans
To: tabi@xxxxxxxxxxxxx ; VICUG-L@xxxxxxxxxxxxxxxxxx
Sent: Wednesday, April 07, 2010 11:20 AM
Subject: [tabi] Braille Displays Promise to Deliver the Web
from the web site,
http://www.scientificamerican.com/article.cfm?id=braille-display-web&print=true
- April 5, 2010
Braille Displays Promise to Deliver the Web to the Blind
North Carolina State University researchers take the first steps toward
making an affordable and more dynamic Braille display
By Larry Greenemeier
The Web's wealth of information would lose some of its luster if you read it
only one line at a time. Yet this is exactly how blind and other
vision-impaired people today must experience the Web when they use electronic
Braille displays connected to their computers.
Braille displays use electromechanically controlled pins, as opposed to the
lights in a conventional computer monitor, to convey information. Here is how:
Software gathers a Web page's content from the computer's operating system,
converts the words and images into a digital version of Braille and then
represents that via a touchable row of finger-sized rectangular cells lined up
side by side like dominoes. Each cell has six or eight small holes through
which rounded pins can extend and retract with the help of piezoelectric
ceramic actuators to represent various Braille characters. Each time a person
reads the row of Braille with his fingers (left to right), the pin
configurations refresh to represent the next line of a Web page's text, and so
on.
Breaking Braille barriers
Efforts to improve Web pages translated into Braille have progressed slowly
because of the cost and complexity of Braille displays, but a team of North
Carolina State University researchers in Raleigh has taken the first steps
toward developing a device that would allow the blind to take better advantage
of the Web and other computer applications. Instead of presenting electronic
content one line at a time, this display would translate words and images into
tactile displays consisting of up to 25 rows, each with 40 cells side by side.
Braille readers would have multiple lines of text and numbers at their
fingertips, enabling them to backtrack and review content more easily. Another
possibility might be to present in Braille equations and other information that
take up more than one line at a time.
"It's difficult to achieve any spatial recognition with just a single line,"
says Neil Di Spigna, a research assistant professor in N.C. State's Department
of Electrical and Computer Engineering who is working on the project.
The use of piezoelectric ceramic to make a Braille display with multiple rows
would make already pricey displays even more expensive-low-end models with a
single row already cost upwards of $1,000. In addition, the amount of energy
needed to power multiple rows would make these displays bigger, heavier and
less portable.
Touch and go
The N.C. State researchers are experimenting with two different approaches
they hope will cut the costs and energy requirements of Braille displays in the
future, and presented their latest research at the International Conference on
Electroactive Polymer Actuators and Devices in San Diego last month.
The first approach would rely on hydraulic pressure to raise and lower each
of the pins in a cell. In this scenario, each pin would sit in a fluid-filled
plastic case. A window would be cut into the case and covered with a
polyvinylidene fluoride (PVDF) film. When electricity is applied to the cell
the PVDF would bend in and squeeze the case through that window, raising the
level of the fluid and the pin along with it. The researchers say they have
demonstrated a proof-of-concept prototype that, when less than 1,000 volts were
applied, got the case to contract and push a fluid consisting of deionized
water and food dye up so that a pin would rise more than 0.5 millimeters-the
standard height of a Braille dot-in less than 100 milliseconds (initial
experiments have been done without a pin in the case).
This is the kind of speed performance a Braille user would expect, says
Peichun Yang, a postdoctoral research associate in N.C. State's Department of
Electrical and Computer Engineering who is also working on the project. Yang,
who is blind, adds that he and his colleagues, including project director Paul
Franzon, have gotten the fluid to move in 30 milliseconds in some trials. Their
next step is to create a latching mechanism within the case that would hold a
pin in place until it needs to be lowered.
The second approach being considered would place each pin in a cylindrical
silicon tube that raises the pin up when the tube is filled with a conductive
solution of calcium chloride and 8.75 kilovolts are applied.
The standard piezoelectric approach to making a Braille display costs about
$35 per cell, according to Yang, who adds that this cost needs to be brought
down to $5 per cell for the displays to be affordable to a greater number of
consumers. The researchers say that more widespread adoption of Braille
displays will depend largely on cost, which was an important factor behind
their research.
Currently, Freedom Scientific, Inc., in Saint Petersburg, Fla., makes several
different computer Braille displays whose cells are laid out in the standard
single-row configuration. The company's portable PAC Mate Braille display is
offered in a single row consisting of 20 or 40 cells, with displays costing
about $1,600 and $3,600, respectively. Freedom Scientific's larger Focus
displays include 40- and 80-cell single-row models, which cost about $3,900 and
$7,800, respectively.
Other approaches
The National Institute of Standards and Technology (NIST) recognized the cost
problem a decade ago, when an 80-cell Braille display cost about $15,000. Since
then, NIST has for several years been working on a display with a much
different design, putting the Braille text on the outside of a spinning
cylinder like the tread on a tire (pdf). The actuators that move the pins in
and out are located inside the cylinder. Instead of moving fingers over a
motionless line of text, the NIST design has the user put one or more fingers
against the wheel, with the Braille text moving underneath the finger,
producing a sensation of motion, which the agency claimed provided stimulus for
the sensors in the fingertips and allowed the user to construct a mental model
of the geometric layout of the text. The user could also adjust the speed of
the wheel's rotation.
Speech synthesizer software that can read the contents of the Web or other
computer text to the blind is an alternative and has the advantage of being
easier to learn than Braille. Still, as NIST notes in its research, Braille has
other advantages, enabling "high-precision communication" and the ability to
read in noisy surroundings.
Speech synthesizers do have a role in helping the blind experience the Web,
Yang agrees, but the ability to read Braille is essential. "Reading Braille is
still very important for [blind people] who wish to work-90 percent of blind
people who hold a job are able to read Braille," he says, adding that
synthesizer technology is one of the reasons why only 10 percent of blind
children are learning to read Braille.
N.C. State's work is still in its early days, so do not expect to see their
Braille display technology at the local computer story in the immediate future.
It could take the researchers as long as a year just to develop a reliable
latching system to keep the pins in place. Only then would they be able to make
an actual Braille display. After that, it could be at least four years to make
a commercial product, Di Spigna says
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