Most of us take it for granted that we can find our way around in buildings, even those we've never been in before. But not Gordon Legge, who studies spatial mobility for vision-impaired people and has a project to help them find their way around indoors.
Unlike streets, indoor passageways don't have names, so even a GPS unit with speech output that worked in a building would have a hard time telling a blind person whether he or she was walking down the right corridor. So Legge, working with Advanced Medical Electronics, has developed a prototype technology to guide them.
"Imagine that every room sign had a bar code," he says. "The user carries a 'magic flashlight' sending out an infrared beam. If the beam hits a bar code, a camera [attached to the person] gets a reflection, reads the code, and compares it to a digital map of the building." The unit can then compute a route and convert the instructions to speech.
In Legge's prototype, the technology is built into a flashlight housing and connected to a computer on a cart. In a few tests so far, low-vision people have successfully navigated indoors, he says.
Legge has a grant to shrink the device and says that in the future, such a system would probably utilize a cell phone to handle the computing. Bar codes would be placed not only by rooms, but near all kinds of landmarks, such as drinking fountains, benches, doors, elevators, and stairs.