自动化立体仓库中出入库任务顺序与出库位置选择集成优化研究

具有多个出口的自动化立体仓库系统是一种将存储和分拣相结合的新型仓储技术,其最典型的特征是在货架底层有很多个出库位置以供取货人员分拣。研究此系统中出入库任务排序与出口选择的集成优化问题,以最小化堆垛机完成所有任务的移动距离为目标,将此问题转化为一个混合整数规划模型。根据问题的特点设计了两阶段启发式算法求解此问题,数值结果表明设计的算法能在较短时间内给出近似最优解,同时与企业常用的先到先服务方法相比,该算法可以缩短超过20%的移动距离。

Joint Optimization of Order Sequence and Pick Position in an AS/RS with Multiple In-The-Aisle Pick Positions

The automated storage and retrieval system with multiple in-the-aisle pick positions (ASRS-MIAPP) is a new type of warehousing technology which combines storage and order picking process. The typical feature is that there exists multiple picking locations at the bottom of the rack for workers. The sequence of storage and retrieval jobs as well as the assignment between the picking locations and retrieval jobs are studied to minimize total travel distance of a storage/retrieval (S/R) machine in an ASRS-MIAPP. A mixed integer programming model is proposed, and a two-stage heuristic algorithm is designed to solve this problem. In the first stage, the sequence of storage and retrieval jobs is selected which is handed over to the second stage where the one-to-one assignment of the picking locations for the given retrieval jobs is determined. The computational experiments show the effectiveness of the proposed algorithm. Compared to first-come-first-served algorithms, commonly used in the practice, the total travel distance reduces on average by 20%.