COMPUTERIZED VIDEO GAIT AND MOTION ANALYSIS SYSTEM AND METHOD

A reflective marker is attached to the front and side of each joint of a subject whose motion or gait is to be analyzed. Each marker is formed of reflective tape and is relatively small and weightless and will not hinder or affect the subject's movements. A pair of Sony Video Motion Analyzers operating at sixty frames per second are positioned to the front and side of a walkpath having a marked centerline along which the subject walks; and coact with video cassette tape recorders to record the subject's movements along the runway. Monitors, provided for playback of the recorded video tape, are each provided with a built-in magnetic disk allowing ten seconds of high-speed motion to be recorded and displayed. A CAT-100 video analysis board, retrofitted into a Z 80 64K TE1 minicomputer, digitizes each recorded video frame to locate by x, y, (or z) coordinates the centroid of each marker and feeds the data into a PDP 11/70 computer which operates on the data to provide line and stick figure outputs of the data and which depict the motions under study; cyclograms of hip angle-knee angle relationships for a cycle of movement of the subject are also provided.