Sonar Walking Stick - Sonar cane helps blind navigate
The visually impaired may soon have a new device to assist them in
sensing their surroundings, a sonar-based walking stick.
From: Nature Events - 09/09/2003
By: Joanne Baker

The small sonar system, mounted on a white walking stick, emits 60,000
sound pulses per second. It also picks up the reflections of these waves
to map obstacles up to three meters away in three dimensions. The stick's
handle contains four pulsating pads that enable the user to feel the
strength of the ultrasound reflections. A fast, strong signal indicates
that an obstacle is close.

Twenty-five visually impaired people in Britain, Germany, Canada, and
Australia have already tested the walking stick, which is expected to
be available by the end of the year.

Read the entire article at:
http://www.nature.com/nature-events/conference-news/baas2003/030908-2.html