A bi-level optimization approach for joint rack sequencing and storage assignment in robotic mobile fulfillment systems  

作　　者：Xiang SHI Fang DENG Sai LU Yunfeng FAN Lin MA Jie CHEN 

机构地区：[1]Key Laboratory of Intelligent Control and Decision of Complex Systems,Beijing Institute of Technology,Beijing 100081,China [2]Beijing Institute of Technology Chongqing Innovation Center,Chongqing 401120,China [3]Zhejiang Cainiao Supply Chain Management Co.,Ltd.,Hangzhou 311101,China [4]Shanghai Research Institute for Intelligent Autonomous Systems,Shanghai 200092,China

出　　处：《Science China(Information Sciences)》2023年第11期123-145,共23页中国科学（信息科学）（英文版）

基　　金：supported in part by National Natural Science Foundation of China(Grant No.61933002);National Science Fund for Distinguished Young Scholars(Grant No.62025301);National Natural Science Foundation of China Basic Science Center Program(Grant No.62088101)。

摘　　要：This paper studies a novel rack scheduling problem with multiple types of multiple storage locations(RS-MTMS),which can decide the retrieval sequence of racks and assign each rack a storage location after visiting a picking station.A major challenge in RS-MTMS is that the storage assignment problem and the retrieval sequence decision are closely coupled.If the RS-MTMS is solved directly,the storage assignment scheme and the retrieval sequence of racks are generally generated separately,thus resulting in poor performance.To overcome this difficulty,we propose a bi-level optimization approach for jointly optimizing the storage assignment and retrieval sequence(Bi JSR).In Bi JSR,the storage assignment problem is solved by variable neighborhood search(VNS)in the upper-level optimization.Effective candidate modes are incorporated into VNS to improve solution quality and computational efficiency.The sequencing optimization is obtained in the lower-level according to the given storage location set.A transformation strategy with sufficient problem-specific knowledge is developed to identify the lower-level optimization as the traveling salesman problem and its variants.Then these identified problems are solved using the loop-based strategy.Experimental results show that the proposed Bi JSR is more effective and efficient than the representative algorithms in solving the RS-MTMS problem.

关 键 词：rack scheduling sequence decision storage assignment bi-level optimization robotic mobile fulfillment system 

分 类 号：F252.1[经济管理—国民经济] TP242[自动化与计算机技术—检测技术与自动化装置]