Patent US 4,137,566

A measurement system obtains and stores digital data on the positions of golf club and significant human body parts during a golf club swing. An interactive display allows later display of the measured performance for use in instruction or review. A coordinate transformer allows the viewing of a displayed simulated golfer from any aspect and at variable speeds and stop action. A generator such as an alphanumeric or graphic generator displays suggested display options, graphics, informative labels, and alphanumeric tabular data. Permanent copies of any displayed picture can be made for later home study.