2003 Conference Proceedings

Go to previous article 
Go to next article 
Return to 2003 Table of Contents 


Jane M Fowler
Sound Foresight Ltd.
Email: Jane.fowler@soundforesight.co.uk
Tel: 44 (0) 1765 676076

Bats are the undisputed leaders in getting around in the world with poor eyesight. They hunt by night when visual information is severely limited. The presentation will explore how, inspired by them, British scientists have devised a high-tech cane for the blind and partially sighted. The 'bat-cane' employs the 'echolocation' technique bats use to detect and avoid objects in their flight path, providing the visually impaired user with a mental picture of their surroundings, enhancing the ability to navigate in the world.

How does it work? Ultrasound waves are emitted to the front, left, right, and upward, with respect to the user. A tiny in-built computer reads the return waves as they bounce off objects, and converts them to vibrations on 'tactors' that the user can feel on the fingers of the hand holding the cane. Direction and distance information are coded into the vibrations such that the brain will learn to build a spatial map, in effect enabling the user to see with touch.

In our brain there is a specialised area, the Superior Colliculus (SC) that encodes spatial information. The SC has maps of audible, visual and tactile environments, and it's primary role is alerting the person to novel objects in their surroundings. By using spatial tactile feedback, albeit on a small portion of the body surface, our onboard computer, i.e. our brain, interprets the tactile input and converts the information into a wider spatial awareness.

Details of trials of the bat-cane are provided from the USA, Canada, Germany and the United Kingdom (in conjunction with established bodies such as Guide Dogs for the Blind (UK), the ACB and AER in the US, and the Canadian National Institute for the Blind); from which interesting client case studies have emerged.

Go to previous article 
Go to next article 
Return to 2003 Table of Contents 
Return to Table of Proceedings

Reprinted with author(s) permission. Author(s) retain copyright.