Did You Hear That? Ultrasound Doppler Effect Allows Echolocation by All


T.Claire Davies , Shane D. Pinder , Catherine M. Burns


New Zealand Acoustics, 21(1), pp.20- 29 . (2008).

Abstract
Individuals with visual impairments must often utilise assistive aids to enable them to complete tasks of daily living. One of these tasks, locomotion, poses considerable risk. The long white cane is often used to perform haptic exploration, but cannot detect obstacles that are not ground5based. Although several devices have been developed to provide information above waist height, they do not provide auditory streams that are easy to decipher. Development of such devices should adapt to the user, not require adaptation by the user. Can obstacle avoidance be achieved through auditory perception? This research presents an auditory interface that has been designed with the user as the primary focus. An analysis of the tasks required and the cognitive load to perform them has been taken into account resulting in an interface that audifies ultrasound. Audification provides intuitive information to the user to enable perceptive response to environmental obstacles. A device was developed that provides Doppler shift signals that are audible as a result of intentional aliasing.