Monitoring the environment: sound localization equipment for deaf-blind people

The problems that deaf-blind subjects have with monitoring the environment and the strategies they use were identified using structured interviews. The use of the vibratory sense did not appear to be highly developed, but some individuals indicated that it has great potential. We describe here the design of a computerized laboratory device for sound localization, based on a three-microphone system with a cross correlation algorithm. It was found to have reasonable precision and sufficient reliability to allow the detection and localization of a person approaching a deaf-blind subject in an ordinary room. The next step is to miniaturize the equipment and build a portable prototype.