Joint Modeling and Optimization of Order Assignment and Picker Routing Problem in Picker-to-Part Systems

Order picking is one of the most labor-intensive and cost-intensive tasks in warehouse management. This paper deals with the joint order assignment and order picker routing optimization problem in picker-to-part systems. Orders are grouped on the basis of their weights and are subject to constraints such as operator capacity limitations and routing. The primary objective is to minimize the total time, which includes the picking and traveling times. The resulting mathematical optimization model is formulated as a mixed-integer linear programming (MILP). The numerical results obtained highlight the accuracy and added value of the proposed approach, thereby providing valuable insight into improving the operational efficiency of order-picking processes in warehouse management.