SWAN: Echolocation-Emulation Device

It’S not quite bat-style echolocation, but people could soon use sound to help them see.

A portable navigational aid that transmits soft, low-pitched beeps directly to the inner ear has been designed to help blind people navigate around cities or guide firefighters through smoke-clogged buildings.

The system guides users with beeps that appear to come from whatever direction the person needs to head in. “We have the user simply walk towards the sound,” says Bruce Walker at the Georgia Institute of Technology in Atlanta, who created the device with colleague Frank Dellaert.

To calculate the user’s position and the direction they are facing, the device uses a processor in a backpack to combine GPS location readings with data from cameras and motion and tilt sensors attached to a headband or helmet. This information is fed into a virtual 3D model of the streetscape or building the person is navigating to calculate which direction the person should walk towards to reach their destination. The device can then generate a series of beeps to guide them.

To make the beeps appear to come from a particular direction, the system varies the timing and intensity of the vibrations transmitted to each earpiece. For example, to make a beep seem to come from the person’s right, the right earpiece will vibrate louder and fractionally before the left, say Walker and Dellaert, who this week announced the development of their prototype, called System for Wearable Audio Navigation (SWAN).

The “earpieces” in fact sit just under each ear lobe and vibrate the skull directly to transmit sounds straight to the inner ear, bypassing the outer ear entirely…