| 摘要 |
<p>A pitching system is provided for throwing baseballs, softballs, and the like, which is synchronized to work in conjunction with a video display (304, 314) to permit a batter to view a moving pitcher (310) prior to and during delivery of the pitch. The machine includes a power head (12) having at least two and preferably three coacting wheels (72) for propelling a ball toward a batter. Three AC motors (80) and companion motor drives are provided for causing the wheels to rotate. The motor drives include dynamic braking circuits to permit rapid deceleration of the wheels. A pair of linear actuators (50, 60) is provided to permit the power head to be moved to predetermined horizontal and vertical positions. A programmable control unit (220) chooses the video image appropriate for a particular pitch and causes the wheels to rotate at appropriate speeds, and causes the machine to assume appropriate horizontal and vertical positions.</p> |
