Design of an enhanced multi-aisle order-picking system considering storage assignments and routing heuristics

Abstract

Abstract Order-picking is the activity to retrieve items from the shelves to fulfill customers' orders. Order-picking is one of the most costly operations in warehousing accounting for 50–75% of total operating costs. This paper presents a novel model that is motivated by the normative order-picking algorithm known as “bucket brigades” to address multiple aisles in warehouses where workers have finite walk-back velocities and are allowed to pass successors. In order-picking operations, the majority of the previous research works have applied bucket brigades over a single-line (serial) system. The contributions of this research work are as follows. (1) A summary of an updated literature review of bucket brigades using a state-of-the-art-matrix. (2) A novel multi-aisle order picking model motivated by the normative single-aisle bucket brigade, which represents a more comprehensive and realistic scenario in order fulfillment warehouses. (3) A comparison between the single-line and multi-aisle models in order to analyze the difference in performance in terms of average system utilization, order cycle time and throughput. (4) A sensitivity analysis of different parameters and scenarios in order to identify the best routing heuristic, storage assignment and order type that maximizes utilization, minimizes cycle time and maximizes throughput in multi-aisle order picking systems. The results of the simulation studies are reported and analyzed. The proposed model is flexible and easily scalable to include other real-life warehousing considerations.