It’s a system targeting maximum storage in minimum area with the use of narrow aisle forklifts in high warehouses as a high rack system.
As the free-space between the racking systems is limited compared to other systems, pallet warehouse area is much more. The operator moves up with the crane to access the products.
In order to create a larger volume of loading/unloading with the help of developing technologies, stacker cranes are used at high speeds. Hence there are guide rails on the ground in order for the crane to move through the aisle properly.
The fact that the aisles are as long as possible increases the efficiency. In some projects magnetic bands on the ground may also be preferred for the stacker. Storing up to height of 16 meters is possible in tailor made solutions.