The research objective is a portable, low cost navigation aid for blind travelers using various modes of transportation. It is directed to orientation, where you are, rather than to spatial sensing which has been the thrust of msot research to date. The system requires nothing but the portable unit itself. New yet proven technology is proposed to provide continuously updated information of position along a predetermined route. Radar, and a compasss are used to input distance and direction to a microprocessor with a speech synthesis output. This is compared with prerecorded distance and direction information on a cassette to aid the traveler to repeat the prescribed course. A portable radar device will be implemented and tested to verify that accurate distance measurement can be achieved from inside a moving vehicle as well as for a walking person. This technology will be combined with experience gained with blind subjects using a simulation of the proposed device to show that such information is adequate for the user to navigate a prescribed route. The principal investigator has developed a commercial product- the Nike Monitor- introduced in May, 1987 that measures distance, speed, time, etc. for sighted runners and walkers.