Wand to aid blind

A "musical" wand to help blind people cross the road is being developed by scientists at the University of Manchester Institute of Science and Technology.

John Cronly-Dillon, professor in the optometry department, is leading a team developing a hand-held camera to help blind people view the immediate world around them. The camera is designed to turn the shapes it sees into sound, enabling blind people to hear their way across roads and around town.

The team started its work by programming a computer to look at simple shapes, such as horizontal and vertical lines, and represent them as sound.

A horizontal line, for example, was represented by a long, steady note, a vertical line was a short mixture of notes, and a diagonal line was a long sound of increasing or decreasing notes.

"We have been looking at the methods the brain uses for processing sensory information," said Krishna Persaud, senior lecturer at UMIST's department of instrumentation and analytical science and a co-worker on the project.

"There appears to be some commonality between the way sight and sound is processed at a higher level."

They have found that both seeing and blind volunteers who once had sight, and therefore have this section of their brain developed, are able quickly to learn the sounds and distinguish with little error between a large number.

The team then went on to give sounds to more complex shapes, such as triangles and cubes.

"We are in the process of seeing how far this idea can be pushed," explained Dr Persaud.

The research team is working on animal movements. Volunteers can distinguish between different animal movement rhythms and also tell when an animal is approaching. Though they cannot distinguish huge detail, shapes, distance and movement appear to be easily distinguishable.

"The ultimate goal would be to produce a small instrument - perhaps a wand containing a tiny camera, that a blind person could use. As the blind person moved around he would be able to move the wand and determine through sound his immediate environment, the shapes around him such as steps and parked cars," explained Dr Persaud.

Even colour may one day be included, with the computer perhaps being programmed to distinguish colour with pitch.

The team, whose work is privately funded, filed a patent on their idea this month.

However, according to Neil Charman, head of UMIST's optometry department, they are still some years off developing the idea commercially.