Abstract: With the rise of online modes such as live e-commerce, order heterogeneity increases and commodity demand changes faster than ever. In the face of frequently changing orders, many e-commerce warehouses are implemented with more flexible storage modes by using movable shelves to quickly adjust the storage layout of the warehouse, so as to improve picking operations. This paper investigates the order picking path with a decentralized storage strategy and movable shelves. A bi-level optimization model is proposed including a joint optimization model of storage location selection and picking path and a shelf movement optimization model. A bi-level meta-heuristic algorithm is designed. Finally, numerical experiments of different scales are conducted to verify the effectiveness of the model and the algorithm.

Key words: movable shelves, picking path, bi-level optimization model, meta-heuristic algorithm