A microprocessor-based ultrasonic limb movement monitoring system.

A system has been devised, using a spark-gap ultrasonic transmitter and an array of four ultrasonic receivers, to monitor the unrestrained movement of a physically handicapped child's fingertip as he attempts to perform some specific task. A microprocessor is used to measure the time taken for a pulsed ultrasonic shock-wave to travel from the fingertip-mounted spark-transmitter to each of the four ultrasonic receivers, and hence compute the Cartesian co-ordinates of the transmitter. It is hoped that this equipment will enable the voluntary components in the poorly-controlled limb movements of some of the physically handicapped children to be isolated and used to control external equipment.