自动化立体仓库控制系统设计与实现

本文介绍的自动化立体仓库控制系统采用由一台工业控制计算机和3台PLC怕集散型控制网络,实现了集监控、调度、诊断、货位分配、堆垛机运行参数给定等功能于一体的自动化立体仓库控制系统和堆垛机制系统以及立体仓库数据库管理系统。工业现场运行证明了这种设计、控制思路的先进性。     

Dynamic availability-oriented control of the automated storage/retrieval system. A computer integrated manufacturing perspective

Dynamic scheduling of the storage/retrieval (S/R) requests and increasing the utilization of the storage spaces, are the two common approaches to improve the efficiency of the automated storage/retrieval systems (AS/RS) in industry practice. However, the actual improvement of the AS/RS has to be justified from the perspective of computer integrated manufacturing system (CIMS) because the ultimate objective of the AS/RS is to assist the CIMS in enhancing its material handling efficiency as well as synchronizing the production. Targeting on this crucial requirement, a dynamic availability-oriented controller (DAOC) is developed in this paper to minimize the mean request fulfilment time of the AS/RS. Firstly, while considering the three types of critical dynamic constraints from the CIMS’ shop floor: the availabilities for both machines and the AS/RS, the process plan of the product, and the production schedule, DAOC is capable of determining the optimal execution sequence of the S/R requests issued from the CIMS and activating dynamic storage space consolidation commands of the AS/RS. Secondly, simulation experiments are conducted and the results show that DAOC successfully improves the S/R request control scheme of the traditional class-based assignment method and significantly outperforms four comparable approaches under various CIMS configurations.     

Optimal random storage allocation for an AS/RS in an FMS

A flexible manufacturing system (FMS) comprises, automated machine tools, automated material handling, and an automated storage and retrieval system (AS/RS) as essential components. Optimal performance of each element of this system would improve the productivity and efficiency of the total FMS. In this context, this paper attempts to link the operation of the AS/RS with the production schedule and suggests two different classes of algorithms, namely, heuristics and genetic algorithms to improve the performance of the AS/RS operation by allocating the materials with minimum movement of the shuttle.     

大型周转型自动化仓库的倒库算法

为提高出库效率,优化自动化仓库的货物布局,提出了基于分层序列法思想的自动化仓库倒库优化算法。根据“货物距离出口最近”和“空筐距离出口最远”原则生成仓库货物的最佳布局位置,以单目标序列优化法对倒库作业进行优化。该算法已应用于某机场大型自动化周转仓库监控管理系统,提高了出入库效率。     

烟丝原料立体仓库堆垛机出入库作业优化研究

为了提高烟丝原料立体仓库堆垛机的作业效率,解决多台堆垛机作业不均衡问题,提出了以各堆垛机作业时间总和最小与作业时间均衡为目标的出入库作业优化模型.在该模型中,用出入库优化作业的规则替代原有作业规则.为了寻求最佳的出入库货位序列,该模型通过构建货位坐标系,采用堆垛机在全速和减速运行状态下联合作业和单作业两种模式的作业时间计算方法,提高了出入库的作业效率.在相同参数下,对一个具体烟丝立体仓库实例进行了作业优化前后的比较.结果表明,通过采用优化作业方法,作业效率每小时可以提高82个烟包,各堆垛机的作业不均衡性大为减小.     

Evaluation and dynamic allocation of AS/RS control rules: A simulation study

The goal of this research is to investigate the performance of an automated storage and retrieval system (AS/RS) which is operated using different control rules. Two phases of study are conducted. Phase 1 evaluates the efficiency of different rules for stacker control, storage-location assignment and job sequencing. Phase 2 studies the impact of these rules on the performance of the AS/RS using a multipass simulation approach. In this paper, the methodology of investigation is discussed, the results are presented and analysed, and suggestions for future study are made.     

自动化立体仓库中载人联机可视化拣选方案及其性能分析

提出了一种新颖的利用网络技术和触摸屏进行载人巷道堆垛机上的可视化拣选操作方案，配合存储货位分配策略和执行批量拣选作业的优化顺序方式，可以提高自动化立体仓库中载人拣选作业方式的工作效率，增加拣选操作的吞吐率，在概述了这种新方案的实现框架之后，给出了这种方案的性能模型，并对具有动态作业插入时的系统性能进行了分析。     

基于两阶段狼群算法的自动化立体仓库作业集成优化

为提高单载具自动化立体仓库动态工况下的进出库效率,针对自动化立体仓库作业集成优化问题建立了仿真优化模型。模型根据货物重质、出入库频率划分货架区域,以指令内最小化单载具堆垛机运行时间为研究目标,设计了一种两阶段狼群算法对其进行优化。该算法使用狼群算法对货位分配和作业调度进行集成优化,求解过程体现出两优化问题之间的关联和反馈。实验结果表明,在不同的订单规模下,相比其他优化方式,两阶段狼群算法能得到满意解,并有效缩短自动化立体仓库的作业时间。     

自动化立体仓库堆垛机拣选作业调度研究

将堆垛机拣选作业调度归纳为旅行商问题，并从遗传算法角度，研究了求解堆垛机拣选作业调度最优路径的具体方法。经过仿真试验验证，这一方法完全可行。     

Dynamic selection of sequencing rules for a class-based unit-load automated storage and retrieval system

This paper studies dynamic selection of sequencing rules for a class-based unit-load automated storage and retrieval system (AS/RS). A multi-pass and genetic algorithm (MPGA) simulation system is developed and it divides storage and retrieval requests or dual commands into a series of blocks, and then conquers each block to find the most promising combination of sequencing rules. These rules are first come first served (FCFS), shortest total-travel time (STT) and shortest due time (SDT), and they can be chosen dynamically in any decision points in the system. An experiment shows that our approach with dynamic rules is much better than those approaches with any single rule used from the beginning to the end in the whole system. The results of this study provide a better way to control and manage the operation of AS/RS.     

Simultaneous optimisation of control factors in automated storage and retrieval systems and FMS using stochastic coloured Petri nets and the Taguchi method

Automated storage and retrieval systems (AS/RS) are playing an important role in modern manufacturing systems such as flexible manufacturing systems (FMS). The integration of AS/RS systems and FMS is very complex owing to the complexity of the individual elements. Stochastic coloured petri nets (SCPN) can be used to model, simulate and analyse such a system efficiently and realistically. In this paper, SCPN based simulation, aided by the Taguchi method of design of experiments, has been used for analysing the influence of important factors on makespan, unproductive travel time, and the mean flow time, and is supported by an example.     

两种多层穿梭车系统的性能比较分析

物流配送中心订单响应速度的加快,对订单拣选系统提出了更高的要求。多层穿梭车系统因其柔性强、效率高等特点,近年来得到了广泛应用。多层穿梭车系统具有两种形式--基于转载车和基于环形输送线,二者均可实现货物的快速拣选,但在系统吞吐量和订单完成周期方面存在差异,致使企业决策者难以进行系统选择。基于上述原因,本文比较两种多层穿梭车系统的性能差异。建立两个系统的开环排队网络模型,然后求解系统吞吐量、订单完成周期,通过仿真验证了排队论模型的准确性,通过试验对两种系统的性能进行对比分析。结果表明,系统吞吐量与层数、巷道数相关,层数越多,巷道数越少,转载车系统相对于环线系统优势越显著;订单完成周期与层数、订单到达率相关,层数越多,订单到达率越低,转载车系统相对于环线系统越具优势。     

An innovative automated storage and retrieval system for B2C e-commerce logistics

Flexible and timely warehousing activities provide a strong foundation for logistic systems. However, increasing B2C e-commerce with a variety of small internet orders may have a tremendous impact on warehousing. Automated storage/retrieval systems (AS/RSs) are a valid alternative for warehousing. Typical AS/RSs design and control problems in a static environment and cannot effectively manage parcel, small, and irregular items. This study proposes a new AS/RS that is more efficient and flexible for handling B2C e-commerce logistics. An auto-access multilevel conveying device (IMCD) with three-dimensional movement is integrated into the AS/RS. The ant colony system algorithm locates near-optimal routes for the IMCD. Typical travel distance/time measures evaluate the performance of an S/R device running on a warehouse floor. However, the performance index in this study looks at the IMCD’s travel time with three-dimensional movement in completing a batch order. To validate the new AS/RS, two simulation experiments were conducted to examine the effects of three-dimensional velocity and rack shape. Finally, this study compares a typical S/R system with the new AS/RS and makes recommendations for practical applications and further research.     

基于MCGS组态软件的自动化立体仓库控制系统的开发

通过设计一套自动化立体仓库,达到解决城市用地紧张,降低劳动强度,提高工作效率等的目的。它的控制系统是以西门子PLC作为控制系统的核心,利用MCGS组态软件设计出自动化立体仓库上位机监控界面,MCGS组态软件通过设备驱动程序从现场硬件设备获取实时数据并处理,通过指示灯显示货物是否完成到位,并由操作人员按照要求将控制指令数据送给现场硬件设备,以控制立体仓库码垛机械手的各种动作,实现对货物的自动化存取。     

Robust clustering approach for the shortest path problem on finite capacity fuzzy queuing network

This paper introduces a new model in the field of fuzzy queuing networks based on the clustering and finite capacity concepts. The proposed model includes fuzzy queuing systems which are located at the nodes of the network. Arc lengths, interarrival times, and service times are all fuzzy triangular fuzzy numbers. In order to find the shortest path on this network, queuing systems should be transformed to waiting times. The waiting times of each system are calculated by a conditional transformation. On the other hand, a robust fuzzy method is proposed for clustering of the arriving customers to the network. Robustness of this method prevents noisy data to affect results. Outputs of the clustering reduce shortest path calculations drastically. Based on a simulation process, the fuzzy queuing network is reduced to a deterministic network. A robust simulated annealing is designed for this network to find the shortest path. Numerical results showed that the clustering process is successful in eliminating outliers, and could be addressed as an efficient method. The convergence and solution time of the algorithm is reasonably better in comparison with published methods. Several experiments are conducted to compare the proposed method with corresponding researches.     

基于FMS的自动化立体仓库监控系统开发与应用术

为了实现对基于柔性制造系统（FMS）的自动化立体仓库（AS／RS）的监控与管理,以浙江机电职业技术学院示范院校建设FMS项目为背景,根据具体实验教学的要求,进行了自动化立体仓库集成监控系统设计,实现了一套功能完备、规范化、工程化的集成监控软件。研究结果表明,该系统的运行效果令人满意。     

Performance evaluation of AVS/RS under various design scenarios: a case study

In this study, performance evaluation of an autonomous vehicle storage and retrieval system (AVS/RS) is completed under various pre-defined design scenarios. Design scenarios are considered based on the rack configuration of the warehouse, namely the number of aisles, bays, and tiers, number of autonomous vehicles (AVs), and number of lifts. The system is simulated using ARENA 12—a commercial software. Seven performance measures are observed from the simulation results. These are: the average cycle time, average utilization of the AVs, average utilization of the lifts, average waiting time in the AVs’ queue, average waiting time in the lifts’ queue, average number of transactions waiting in the AVs’ queue, and average number of transactions waiting in the lifts’ queue. Total cost of the system is also integrated into the analysis. The results are analyzed via graphs. Various design options and their costs facilitate the evaluation of the best design for the warehouse manager. The case study is completed for a company that utilizes AVS/RS in France.     

具有AGV和AS/RS的装配线物流系统分析

阐述了具有自动导引车(AGV)和自动存取系统(AS／RS)的物流系统的工作流程，建立了该类物流系统的排队网络模型，分析了系统的性能与系统设计参数之间的关系，为设计具有AGV和AS／RS的复杂物流系统提供依据。     

Travel-time models for flow-rack automated storage and retrieval systems

In this paper, closed-form travel-time expressions for flow-rack automated storage and retrieval systems are developed. The expressions, which are based on a continuous approach, are compared for accuracy, via simulation, with exact models which are based on a discrete approach. There is no significant difference between the results obtained from the continuous-approach-based closed-form expressions and the ones from the discrete-approach-based exact solutions. The closed-form expressions are easy to calculate due to their simplistic forms, even without a computer, while the exact solutions are extremely complex. On the basis of computation time, the proposed closed-form expressions are extremely practical when compared with the discrete-approach-based expressions, which require extensive computation time. The closed-form travel-time expressions developed in this study can be used to (1) establish performance standards for existing AS/RS, (2) evaluate throughput performance for flow-rack AS/RS alternative design configurations, and (3) compare different storage techniques for improved system performance. Due to their simplistic, yet accurate, definitions, the closed-form expressions, as well as the results of this study, are applicable to industry.     

Dual commands dispatching of a class-based unit-load automated storage and retrieval system using multi-pass simulation with generic algorithm

A simulation system with the approach of multi-pass and genetic algorithm (MPGA) is developed for dispatching dual commands by a stacker machine in a unit-load/class-based automated storage and retrieval system (AS/RS). Three single-rules, FCFS/STT, SDT/STT, and STT_bk, are run individually by a single-pass simulation and served as the benchmarks to compare with the performances of three kinds of the MPGA approach. All experiments, singles and MPGA, start with the same initial system states and run with the same input data streams. Due to a larger solution space for the optimal search and an iterative searching method, the MPGA approach greatly improves the performances of our AS/RS model, compared with traditional approaches.