抄録
We are developing a system to confirm 3-D coordinate (x, y, z, t) of golf ball flight trajectory by using video camera image. Information of tilt θ _c(t) and pan φ _c(t) angles of the camera are detected by two rotary encoder. The absolute distance r(t) from the camera to a golf ball will be detected in relation to the number of pixel area of a golf ball on the screen. The center position of the golf ball on the screen is transformed into the tilt θ _s(t) and pan φ _s(t) angles of the camera, then they revise θ _c(t) and φ _c(t). Finally, 3-D position (x, y, z, t) of the ball are decided from spherical coordinate system (r(t), θ(t), φ(t)).