A multifunction domestic alert system for the deaf-blind

Describes an electronic system to alert a deaf-blind man to the occurrence of a variety of household sounds-such as a doorbell, telephone or a smoke alarm-and to inform him about the source of any such sound. The system has been designed to be effective, reliable, relatively inexpensive, to avoid any necessity for direct connection to domestic appliances and (within limits) to be adaptable to other potential users' requirements. It consists of a fixed-position audio-analysis and recognition unit (ARU) which, on detecting and recognizing a specific environmental sound, transmits information by radio to a vibrating portable unit (PU) worn by the deaf-blind person. The detailed pattern of vibration codes the source of the sound, and hence indicates its identity to the user. Starting with tape recordings of environmental sounds from the house of the deaf-blind client, a prototype system has been built and tested. Subsequently, the system was installed in his home and, after some initial adjustments, has operated reliably and trouble-free to date (a period of almost three years). A requirement for an alert system for environmental sounds is common to many deaf or deaf-blind people, so that some attention was paid to adaptability during design. For those having domestic appliances not too different from the present client, the system should be usable with a certain amount of modification.