Wirelessly Enabling the Disabled
By David Pescovitz, Wed Feb 18 00:15:00 EET 2004

For most of us, mobile devices are a luxury. But for the 50 million disabled people in the United States, and countless more around the world, wireless technology may soon be a liberator.


Researchers at the Rehabilitation Engineering Research Center on Mobile Wireless Technologies for Persons with Disabilities, located at the Georgia Institute of Technologies, are hacking a variety of off-the-shelf components and mobile devices to improve the quality of life for individuals with various impairments.

From wearable computers that help the blind navigate to gesture-based interfaces for consumer electronics, "all of our projects are designed to increase a disabled person's independence," says center director Helena Mitchell.

Founded two years ago on a $5 million, five-year federal grant from the National Institute on Disability and Rehabilitation Research, the Center is already testing its first prototypes. All of the devices are built from off-the-shelf components to keep costs down and accessibility high. Design priorities are informed by in-depth field studies and interviews.

"Often, these kinds of devices are created in a vacuum by people who are pushing the envelope technologically," she says. "But it's important to always be thinking about the user."

One system, called an "auditory display," combines GPS, a mobile PC, and headphones outfitted with a head-tracking sensor to help blind individuals navigate on their own. The GPS receiver pinpoints the wearer's location and the head-tracker monitors which direction he or she is facing. Meanwhile, the computer generates spatial sound signals, tones that the user perceives to be emanating from a specific direction. Once a path has been programmed into the system, the user then follows the sound cues like virtual trail markers to get to his or her desired destination.

Another major research thrust of the Center is the study and development of wireless interfaces. For individuals who have limited motor control, even switching on lights or changing the television channel can be a challenge. The Center's "gesture panel" and "gesture pendant" help simplify the interaction with household devices by translating movement into computer commands, not unlike Tom Cruise "conducting" his computer in Minority Report.

The panel contains 72 light-emitting diodes that beam infrared light at a video camera. As the user breaks the beams with a hand movement, his or her gestures are translated by computer into a wireless commands for household appliances. The gesture pendant is essentially a wearable universal remote that instead of buttons features a tiny video camera that captures hand movements. A thumbs-up, for instance, might increase the volume of a mobile telephone. Not surprisingly, this kind of gestural computing technology has applications beyond aiding the disabled.

"The automotive industry has already expressed interest in creating a similar gesture interface in cars," Mitchell says. "Many accidents are caused by people who aren't concentrating on driving because they're reaching for something like the radio."

The researchers are also examining the commercial potential of their Wearable Captioning Device, a wireless system for hearing-impaired audience members catching a film or attending a meeting. Currently, the best captioning technology offered by some movie theaters is Rear Window, an LED display mounted at the rear of the theater. The system synchronously displays mirror-images of captions fed from a CD-ROM included with the film print. Hard-of-hearing audience members watch the film through transparent reflective panels mounted on the chairs. The panels reverse back the caption displayed on the LEDs and create the illusion that the text is superimposed on the film. Rear Window captioning may not alter the moviegoing experience for the hearing audience, but it's certainly not the most elegant solution.

"It's awkward," Mitchell says. "Even if the text is provided on the screen itself (at the bottom), you have to constantly look at the words and you miss the picture."

The Center's solution is simple, yet effective. Captions already embedded in films are transmitted to a PDA, either belonging to the patron or borrowed from the theater. A tiny monitor that clips on any pair of eyeglasses virtually suspends the caption in the wearer's field-of-vision. Of course, live settings require a typist to provide the captioning. As speech recognition software improves though, it's easy to envision a PDA-based portable captioning system so hearing-impaired individuals can read their real-world conversations without breaking eye contact.

Along with these specific projects, the Center hopes to develop an entire class of wireless "cognitive prostheses." For example, systems that integrate Blackberries with touch screens and speech synthesizers not only provide on-the-go email access but could also remind the user to take his or her pills or inform them that a ride will arrive at a certain time. Unlike wrist-worn timers already available, wireless Internet access enables the gentle nudges to be updated by others even if the user is out for the day.

While the Center's efforts are focused on wirelessly enabling the disabled of today, the innovative technology will eventually impact us all.

"The population is aging and older people develop disabilities," Mitchell says. "Why can't we develop technology now that will make life easier for all of us?"