Before a genetic disease damaged Michael Hancock’s vision, he was an avid pilot, an avocation that inspired his current research. Hancock, a neuroscientist at the University of Texas Medical Branch at Galveston, has developed a system of infrared beacons that will help blind people find their way inside unfamiliar buildings. He calls his invention find, for friendly infrared navigation device, and modeled it after aircraft navigation technology.
The beacons in Hancock’s system are placed over office doors, rest rooms, water fountains, and elevators, or at relay points like hallway intersections. Each beacon sends a set of numbers, coded in infrared signals, down both directions of a hallway. The beacons flash one after the other, rather than simultaneously, to prevent interference among the signals. The numbers indicate the room, floor, and hallway where the beacons are located. To get to a room marked by a beacon, you use a small receiver, about the size of a television remote-control unit, which picks up the infrared signals. Using a braille list, you punch in a room number and then point the receiver around until it finds the infrared signal of the closest beacon.
The receiver is programmed to know which beacons are between you and the target beacon. If the room you want is on a different floor, the receiver will automatically send you to an elevator. But if the first beacon the receiver picks up is on the way to the destination, the receiver beeps (or if a person is also deaf, it vibrates). If that beacon is not on the way, you sweep the receiver around until it finds one that is. As long as you’re hearing those beeps, you’re on course, says Hancock.
Once you are in the right hallway and within 100 feet of your destination, the receiver will pick up the target beacon and lock out all other signals, giving you double beeps to tell you that you’ve found the right beacon. When you are within three feet of the room, a weaker beacon, placed lower on the wall, takes over and guides you with triple beeps to the doorknob.
Hancock is working on improving the system. He has just installed a voice chip in the receiver to replace some of the beeps with spoken directions. To date he has successfully tested FIND at the Texas School for the Blind and Visually Impaired in Austin. For blind children that go to school, this system would give them some independence, says Hancock. They wouldn’t have to have a buddy take them places.