Diagonal cross-aisles in unit load warehouses to increase handling performance

This work proposes a non-conventional easy-applicable configuration for unit load (UL) warehouses, with the aim of improving the handling performance in terms of the travelled distance. The impact of the adoption of one or more straight diagonal cross-aisles within a traditional warehouse is investigated under single command operations. The closed-form of the mean travel time with random storage assignment of the ULs is provided and the design parameters of such a warehouse are evaluated. In the optimal configuration, the travelled distance savings range from 7% to 17%. The loss of storage area related to the presence of the diagonal cross-aisles is, also, evaluated, leading to define the profitability regions, best balance between the distance saving and the storage area loss, driving the choice of the most effective number of diagonal cross-aisles to include within the storage system.