Patent ID: 7686701

Claim:
A shaft behavior automatic measuring system for measuring the behavior of a shaft in a golf club as the golf club undergoes a swinging movement imparted by a swing actor, the system comprising: a metal member provided on a surface of the shaft in the golf club and a Doppler radar; the Doppler radar including at least one transmitting portion for emitting a radar wave to the metal member in the golf club during the swinging movement and at least three receiving portions for receiving the radar wave reflected from the metal member; wherein a distance between the Doppler radar and the metal member throughout the swinging movement is at least 0.5 m and no more than 8 m; and wherein the wave emitted by the Doppler radar has (1) a beam width in a horizontal direction that includes the horizontal range of the movement of the metal member and (2) a beam width in a vertical direction that includes the vertical range of movement of the metal member; and a calculating portion for calculating three-dimensional coordinates of the metal member based on a signal received by the at least three receiving portions.