Incorporating vertical travel into non-traditional cross aisles for unit-load warehouse designs

Abstract

This article proposes modifications to the travel-time models for non-traditional warehouse aisle layouts, Flying-V and Fishbone, by incorporating a vertical travel dimension. The resulting non-linear optimization models incorporate Chebychev travel within the picking aisles. The obtained shape of the aisle and the percent improvement for a traditional warehouse are compared with the results found in previous research that ignores vertical travel. It is shown that the percent improvement diminishes as the height of the rack increases, with Fishbone maintaining a higher percent improvement over Flying-V. It is also shown that while the shape of Flying-V can be considerably altered by considering vertical travel, the Fishbone layout often maintains its recommended shape regardless of the height of the rack. The article concludes with recommendations for effective implementation of these two designs.

Keywords:

• Non-linear optimization
• warehouse design
• non-traditional aisles
• Flying-V
• Fishbone
• Chebychev travel