Material Handling System Design Research Articles

Vehicle Travel Time Models for AGV Systems under Various Dispatching Rules

The design and evaluation of AGV-based material handling systems are highly complex because of the randomness and the large number of variables involved. Vehicle travel time is a fundamental parameter for solving various flexible manufacturing system (FMS) design problems. This article presents stochastic vehicle travel time models for AGV-based material handling systems with emphasis on the empty travel times of vehicles. Various vehicle dispatching rules examined here include the nearest vehicle selection rule and the longest idle vehicle selection rule. A simulation experiment is used to evaluate and demonstrate the presented models.

Integration of expert system with analytic hierarchy process for the design of material handling equipment selection system

A key task in the material handling system design process is the selection and configuration of equipment for material transport and storage in a facility. Material handling equipment selection is a complex, tedious task, and there are few tools other than checklists to assist engineers in the selection of appropriate, cost-effective material handling equipment. This paper describes the development of an intelligent material handling equipment selection system called material handling equipment selection advisor (MHESA). The MHESA is composed of three modules: (1) a database to store equipment types with their specifications; (2) a knowledge-based expert system for assisting material handling equipment selection; and (3) an analytic hierarchy process (AHP) model to choose the most favorable equipment type. The concept proposed in this paper can automate the design of a material handling equipment selection system, and provides artificial intelligence in the decision-making process.

Advanced material handling system for computer integrated manufacturing

A cordless linear synchronous motor (LSM) material handling system for CIM has been developed. The system incorporates a courier that moves without tether restrictions. This provides for an automated material handling system with improved travel and flexibility. The material handling system runs on an integrated reverse air bearing system which eliminates friction and backlash. The proposed system forms part of a manufacturing assembly, interacting with overhead manipulators and part feeders to form a comprehensive production system. The design and implementation of the cordless linear motor material handling system (MHS) is outlined and described in the paper.

Design and operation of single-loop dual-rail inter-bay material handling system

Asynchronized automated material handling systems, e.g. automated electrified monorail systems and automated guided vehicle systems, have been playing important roles in manufacturing. Reliability becomes a critical issue as manufacturing enterprises are moving toward automation. In the past, reliability tissue has not been analysed explicitly for these types of systems. In this research, a new measure was proposed to specify reliability. A mixed integer programming model was developed to design flow paths for a special class of material handling systems, i.e. single-loop dual-rail systems. The model can be used to design systems with higher reliability. The model and application procedure in design and analysis were demonstrated through two case studies.

Semiconductor fabrication facility design using a hybrid search methodology

The use of integrated circuits (ICs) is ever increasing in the past decade and will continue to increase in the foreseeable future. To compete successfully in global markets, semiconductor manufacturing facilities require good system performance in terms of high throughput and high yield on wafers with smaller line widths and larger diameters, while still maintaining low system costs. The installation of an automated material handling system (AMHS) within a typical bay layout configuration is a viable approach for improving system performance as well as reducing operating and capital investment costs. Integrated approaches for fab layout and AMHS design generally involve mixed integer programming (MIP) formulations that are difficult to solve for large size problems. This paper proposes a hybrid search methodology based on tabu search and simulated annealing to solve such layout and AMHS design integration problems in a wafer fab. The procedure was computationally tested for efficiency and effectiveness against an existing MIP formulation. The results indicate that the proposed procedure performs very well in terms of both solution quality and computation time. It is shown that this procedure is extendable to other layout and material handling system design problems.

Minimization of acquisition and operational costs in horizontal material handling system design

This paper considers the problem of minimizing the fixed cost of acquiring material handling transporter:; and the operational cost of material transfer in a manufacturing system. This decision problem, which arises during manufacturing facility design, is modeled using an integer programming formulation. Since the problem is NP-complete, two efficient heuristics are developed to solve it. Computational complexity, worst-case performance analysis, and extensive computational tests are provided for both heuristics. The results indicate that the proposed methods are well suited for large-scale manufacturing applications.

System reliability and congestion in a material handling system

Congestion in a transportation system prevents vehicles from traveling freely. Therefore, congestion in a material handling system can reduce the system's performance. This paper: (1) develops an analytical methodology for measuring congestion in a material handling system, (2) develops a congestion measure that is measurable in real-time and readily incorporated into existing analytical models for material handling system design and (3) develops quantitative relationships between critical material handling system variables and system congestion.

Design of an Automated Shop Floor Material Handling System with Inventory Considerations

Material handling systems are almost always intertwined with the production system they serve, but problems at this interface are rarely considered together. This paper develops a model that explicitly considers the costs of material handling and inventory to simultaneously design a material handling system and set shop floor inventory policy. The research was inspired by material handling problems we observed at computer manufacturing companies such as Apple Computer and Hewlett Packard Company. Shop floor inventory policies are often a result of trial and error or simple usage calculations—and material handling system design is usually addressed given an existing inventory policy. However, a tradeoff exists between shop floor inventory policy (reorder quantities and safety stock amounts) and demands for material handling. Inventory decisions can have a particularly large impact on cost when an automated material handling system, such as an automated guided vehicle system, is used to deliver materials. This paper develops a material handling/inventory system design model that is a nonlinear mixed integer program with nonlinear constraints, and presents a solution approach based on decomposition. Computational results show that simultaneous consideration of inventory policy and material handling system design can lead to significant reductions in overall production cost.

An integrated approach for facility layout, P/D location and material handling system design

This paper describes an integrated model for solving the facility layout, pickup/ drop-off locations and material handling equipment selection problems. A heuristic algorithm to solve the combinatorial problem is developed and implemented. The model to solve the facility design problem is formulated as a nonlinear mixed integer program. The proposed approach simultaneously determines the facility locations, pickup/drop-off points and material handling equipment. Due to the complexity of the problem structure, a Tabu Search metaheuristic procedure is used to solve the integrated problem. In addition, two heuristic procedures for solving sub-problems are developed. Four sets of example problems are studied, with the results of the integrated approach being better than the results of the traditional approach, i.e., solving the problems separately. The approach presented in this paper not only integrates many of the significant factors in the facilities design, it also minimizes the overall facility design costs and enables the designer to explore system designs more thoroughly.

A mathematical programming approach to simultaneous unit-load and fleet-size optimisation in material handling systems design

This paper develops a model for simultaneously determining the optimal performance-based unit-load and fleet sizes for material handling vehicles serving work stations in a manufacturing system. The mathematical programming model maximises the number of units transported by the material handling vehicle during a given production cycle. The optimisation model simultaneously specifies the unit-load and fleet sizes, based on material transportation requirements and system characteristics.

An Integrated Model of the Material Handling System and Unit Load Design Problem

Material flow system design problems (i.e. facility layout, material handling equipment selection and specification, flow path design, unit load sizing, cell design, warehousing, routing, etc.) have been predominately modelled independently in the past. Independent consideration of each design problem has reduced the solution complexity, but in the process has caused a loss in problem reality. This paper reviews recent developments in integrated approaches to material flow design and presents a model which integrates material handling equipment selection and specification (including material handling interface equipment) and path/load dependent unit load size. The formulation is solved using the meta-heuristic procedure of tabu search to find good solutions to the more realistic (and more complex) model formulation.

Performability-based fleet sizing in a material handling system

This research examines the problem of determining the optimal fleet size for fixed-path material handling systems on the bases of performance and reliability, simultaneously. In this paper, a regression model is developed to study the relationships among various material handling system design characteristics (fleet size, guide path layout, and number of P/D stations, vehicle speed and failure rates, guide path intersection failure rates, and P/D station failure rates) and performability, measured as the average number of material moves between failures (MBF). The regression model highlights the important relationships between the selected factors and performability, and may be used to determine the performability-based optima for the controllable design characteristics.

Performance, reliability, and performability of material handling systems

A number of different performance measures have been used in the design and analysis of material handling systems. These performance measures have measured either: (1) the entire manufacturing system (e.g. job throughput), or (2) the material handling system independently (e.g. vehicle travel distance). The following is a review of performance, reliability, and performability measures used in the analysis and design of material handling systems in a manufacturing environment.

Performance-based unit-load optimization in material handling systems design

This paper developsa mathematicalmodel for determining the optimal unit load sizesfor material handling vehicles serving work stations in a manufacturing system. Previous research in fleet size specification has been based primarily on minimizing total manufacturing costs. Although system cost minimization is a common and important performance measure, it fails to consider the operational performance of the system. The model presented here addresses this need by optimizing operational performance; more specifically, by specifying

Recent Advances in the Design and Analysis of Material Handling Systems

We present an overview of recent research in the design and control of material handling systems. Research in both shopfloor transportation systems and storage systems is covered. The issues studied range from the integrated design of manufacturing facilities and material handling systems to the performance analysis of operating policies in these systems. In general, the design and control problems in material handling systems are very hard, but analytical results can be obtained for specific configurations and relaxations of the problem.

Advances in discrete material handling system design

The paper presents an outline of the research done in the area of facility layout and discrete material handling system design. The objective of this paper is to observe the trend in the literature in the area of manufacturing system design and predict the direction of future research in this area. The paper attempts to link the areas of facility layout design and material flow network design. A methodology for solving the integrated design problem is presented. An algorithm which aids in solving the combined pick-up/drop-off point location and material handling flowpath problem is outlined.

Integrated facility layout and material handling system design in semiconductor fabrication facilities

Semiconductor manufacturing is an important component of the U.S. manufacturing industry. Most of today's fabrication facilities and those being designed for the near future use a bay layout configuration and an overhead monorail system for moving material between bays. These material handling systems are usually designed with a spine or perimeter type of configuration. This paper investigates the layout and material handling system design integration problem in semiconductor fabrication facilities and proposes a methodology for solving this integrated design problem. A spacefilling curve approach is used to address the facility layout, while the structure of the spine and perimeter configurations are exploited to create a network flow problem to determine the material handling system design. Computational results are presented and show exceptional promise for this procedure in solving the integrated design problem in a semiconductor manufacturing environment.

Stochastic Modeling for Automated Material Handling System Design and Control

Material handling systems (MHSs) are micro-transportation systems that share many of the same challenges in design and operation as their larger-scale transportation counterparts. However, because of the automation technology employed in material handling, such systems also present many new challenges. Over the past decade, progress in automation technology has led to the replacement of many non-automated MHSs with automated systems. Use of an automated MHS can lead to significantly lower overall material handling cost, and thus overall production cost. However, the installation cost of such a system can be significant, and an MHS that does not function properly can lead to significant losses in productivity and profits. Analysis of design and control problems for such systems must take into account the fact that MHSs typically operate in a stochastic environment, with stochastic demands for material handling, flexibility in vehicle routing, variable processing times and other random elements. This paper reviews research on design and control of automated MHSs, with emphasis on analytical models that incorporate stochastic elements. We focus on models of automated storage and retrieval systems and automated guided vehicle systems. In addition to evaluating the existing literature, we describe areas where further research is needed.

ICMESE: Intelligent consultant system for material handling equipment selection and evaluation

Abstract Material handling equipment selection, a key concern in material handling system design, is a complex, difficult task and requires extensive technical knowledge and systematic analysis. It is invaluable to justify the selected equipment model by performance evaluation before actual implementation. This paper presents an intelligent knowledge-based expert system called ICMESE for selection and evaluation of material handling equipment suitable for movement and storage of materials in a manufacturing facility. ICMESE consists of four modules: (1) a knowledge base to select an appropriate equipment type, (2) a multicriteria decision-making procedure to choose the most favorable commercial model of the selected equipment type, (3) a database to store the list of commercial models of equipment types with their specifications, and (4) simulators to evaluate the performance of the equipment model. The whole process of ICMESE is executed under an expert system environment.

Design and implementation of an automatic material handling system in a batch production environment

This paper presents the problem definition and the related research activities on the modeling, simulation, design and implementation of an automatic material handling system in a batch production environment. The colored and timed Petri nets are used to model and simulate the automatic material handling system. The Petri net modeling and simulation enable the determination of the design parameters of an automatic guided vehicle and an automatic storage/ retrieval system, and also the estimation of the expected performance capability of the whole system. Finally, the whole system has been implemented for a specific batch production line. The comparison of the performance capability expected by the Petri net simulation and that measured from the real-time running of the whole system shows a good agreement.