Abstract: A pitching system will pitch either softballs or baseballs to a single station. At least one of the pitching machines in the system can have variable speed pitches. As the speed of the pitches changes, the angles at which the balls are thrown will be varied. In that manner, the strike zone at the batting station can be maintained. The pitching system includes a pitching machine with rotatable upper and lower wheels. Balls are fed to and thrown from these wheels. The speed at which the balls are thrown by the wheels can be adjusted. When the speed is adjusted, a control will actuate a tilting device for adjusting the angle at which the balls are thrown. This angle is decreased as the speed of the thrown balls is increased.

Abstract: A system for controlling at least one go kart in an operation area includes a general transmitter, an area transmitter, a receiver unit on each go kart and an idling device. The operation area includes a track and a pit area. The general transmitter is either a radio transmitter or a loop which encircles the entire operation area. Upon activation of the general transmitter, a signal is emitted such that go karts anywhere in the operation area are idled by the idling device. Activation of the area transmitter, on the other hand, will cause the idle device to idle go karts in at least one of the pit area and an approach area to the pit. This area transmitter includes a loop which encircles the pit area and/or the approach area. A control device with a timer is provided to automatically activate the area transmiter when a predetermined time has elapsed. The control device will also permit an operator to activate the general transmitter when an emergency situation arises.