Drawing on echolocation principles used by bats and dolphins, a group of
students at Wake Forest University, North Carolina, developed a watch prototype
that uses sonar signals to paint a picture of the built environment.
The watch has two sonar distance sensors that send signals out into the
environment and measure the distance they travel before hitting an object.
This distance is changed into vibrating feedback on the wearer's wrist, like
a haptic collision warning system.
William Conner, a biology professor at the University who advised the
developers, says a sonar watch isn't a totally new idea.
Using sonar as a way to help the visually impaired has been the subject of
research for a while now.
A quick search in the Internet will show you sonar hats and sonar-enabled
canes. But there's a big difference says, Conner
"The watch uses tactile, not auditory feedback," he says.
The device has a range of about three feet, so it only buzzes when you're
directly in front of an object.
The vibrations hit on your wrist - the closer you get to the object, the
more frequent the buzz.
"By sweeping an arm, the user can
scan the object to get a sense of how big it is. It's kind of like a sonar
flashlight," says Conner.
Jack Janes, a senior computer science and physics major who worked on the
project, said that it's not a standalone device.
"Right now you'd want to use it in tandem with a seeing dog or some
other form of way-finding," he explained.
But the potential for this technology's future is exciting.
Attaching sensors and vibrators like a belt around the torso could enable
users to get a bigger picture of their surroundings.
"It would take an upgrade in sensors and processing, but you could imagine
how someday it might be possible to imprint more
detailed, two-dimensional images onto the user's skin.
We'd have to know a lot more about echolocation, how
the sounds process and have a much better interface. But it's just a matter of
time," says Conner.