An overview of the advantages and disadvantages of common systems
What are the building requirements?
Shelf-to-person systems can be installed with low hall heights and a normal, level industrial floor, while the use of AutoStore, with maximum stored goods height, requires a hall height of 7.5m and a load-bearing floor. Due to the high point load and the required tolerances, the load capacity and rigidity requirements of the floor for the construction of a shuttle warehouse or automated small parts warehouse are even more significant. Autostore, shuttle warehouses and storage and retrieval systems often also have to meet special requirements in terms of fire protection.
Which system enables compact storage on a small footprint?
Because no aisles are needed to move the robots, Auto-Store allows for very compact storage. However, the maximum system height is only 5.4m. Shuttle storage and automated small parts storage require more floor space, but offer the ability to make optimal use of building or hall height. Due to the limited rack height, rack-to-person systems do not show an optimal use of space in higher halls.
What degree of flexibility is possible?
Shelf-to-person systems are very flexible in terms of rapid response to changes in assortment. Shelving can be adapted to items of different sizes and shapes – z. B. Also to hanging garments. With the other solutions, flexibility is limited by the system-related storage in containers. There are shuttle and stacker crane load handling devices that automatically adjust to different container sizes, but with AutoStore, standardized sizes must be used.
How far are the systems scalable?
While the output of the automated small parts warehouse is limited by the aisle capacity, it can be increased to the performance limit in the other systems by using additional vehicles without conversion measures. To increase capacity, shelf-to-person systems and AutoStore can be expanded by adding individual shelves or. Shafts to be added. At the shuttle warehouse. Additional lanes will have to be built for the RBG. Additional aisles need to be built at the shuttle warehouse and RBG.
How redundant are the systems?
The stacker crane has no redundancy in the event of a malfunction – the entire aisle is at a standstill. Partial failures may also occur with the shuttle, depending on the system. In shelf-to-person systems and AutoStore, on the other hand, the robots can be serviced individually and on the fly, without affecting the rest of the system. How is picking done. How high is the picking performance?Basically, goods-to-person systems allow a very high picking performance due to the stationary workstations. The actual performance is determined by the job structure. The setup of the workstations is influenced – for example, whether picking is done there 1:1 or 1:n. Also ancillary activities such as pick& Pack influence productivity. Due to manual picking from different rack levels, the picking performance of rack-to-person systems is lower compared to the other systems. This is also detrimental in terms of ergonomic conditions for employees.
Conclusion: Which system is best suited to your logistics??
Which system is suitable depends on the area of application and the company-specific circumstances. The challenge is to ensure flexibility, scalability and expandability of logistics while keeping an eye on system economics.