US Patent 8424983 Motorized upper and lower storage shelves

A storage VBS with opposing side walls, a top, a bottom, a back with an open or openable front, houses moveable upper and lower adjustable shelving boxes. The shelving boxes are moveably motorized and controlled sequentially. An upper shelf is made accessible by driving an upper shelving box out of the VBS and then adjusting the shelf height for storage or retrieval of an item. The upper shelving box must be returned to the VBS prior to operating the lower shelving.