摘要 |
<p>A storage and retrieval system is controlled to prevent "grid lock", or interference between items exiting or entering the system and those items in transit within the system. The control method comprises the steps of determining if the system is or is not at saturation, if there is adequate space in exit and entry queues, if there is or is not absence of space in the conveyor loop sections adjacent to the loop conveyor entry points, and if or not there is adequate space ahead of an exit point, followed by imposition of delays and other actions preventing the interference of items already in the conveyor system, or entering or exiting therefrom. The control means can be a programmed general purpose computer.</p> |