BIOMIMETIC SYSTEMS, INC.
The goal of this project is to develop a sonar system that can be used as a mobility aid by the visually impaired. The system will consist of an ultrasonic acoustic source using a waveform that is designed to optimize target discrimination and a pair of miniature microphones that are mounted near the ears to create natural interaural level and timing differences. A heterodyning technique will be used to shift the signals received by the micrphones down to the audible range after which it will be presented to the user through open-canal earphones. The acoustics source and microphone arrays will be mounted on the user's head so that he/she can scan his/her environment with the sonar system using natural head movements. The specific aims of this Phase I STTR includes constructing a semi-portable prototype and a series of experiments designed to demonstrate the usefulness of the device. This research will lead to a new mobility aid for the visually impaired. It will also help she light on how visually impaired subjects might be taught to use unaided echolocation to navigate through complex environments.