Implementation Of Cellular Manufacturing Research Articles

Solving the integrated cell formation and worker assignment problem using particle swarm optimization and linear programming

Both cell design and human issues are important factors for successful implementation of cellular manufacturing. To better implement cellular manufacturing, we investigate the integrated cell formation and worker assignment problem (ICFWAP). A comprehensive linear model is developed for the ICFWAP to determine the optimal allocation of machines, parts and workers. Specific characteristics of this model include the simultaneous consideration of production planning, coexistence of alternative process routings, lot splitting, workload balancing between cells and worker over-assignment to multiple cells. Motivated by the inefficiency of exact approaches, this paper proposes a hybrid approach combining combinatorial particle swarm optimization and linear programming (CPSO-LP) to efficiently solve real-sized problems. In CPSO-LP, decision variables corresponding to part routing selection and part operation assignment are fixed and other variables are allowed to be changed. CPLEX is then used to solve the reduced LP problem. Numerical experiments validate the proposed model. Results reveal that worker over-assignment can reduce the number of workers hired and improve labor utilization rate. The better efficiency and effectiveness of CPSO-LP are proved by comparisons with CPLEX, a genetic algorithm (GA), CPSO, and a hybrid approach combining GA and LP.

Ordered indices of the production structure of manufacturing systems based on an information-theoretic approach

The production structure of a manufacturing system not only influences its transportation and operation cost, but also affects logistics and parts/machine assignment decisions. Based on the sending and feedback mechanisms of information, the principles of conditional entropy and classical probability are utilized to establish structure entropy models and ordered indices of the system with dynamic characteristics and generality, which provide effective solutions for the absence of quantitative method in evaluating the structural optimization of production system. In an empirical study, this paper analyzes different production structures when workpieces are processed by different working routes before and after the implementation of cellular manufacturing. Afterwards, the developed structure entropy models and ordered indices are utilized to calculate the orderliness of production structure under the two different states. The final result verifies well the validity of this quantitative method for evaluating the orderliness of production structures.

Metaheuristic Techniques on Cell Formation in Cellular Manufacturing System

Cellular manufacturing system is a submission of group technology wherein are different machines or processes have been combined into cells, each of which is devoted to the fabrication of a part, product family, or limited group of families. Cell formation is necessary for implementation of cellular manufacturing. Many of methods exist for cell formation problem solving. Some of these methods are applying in traditional cell design, in fixed routines and others are applying in dynamic cells environment. In this review article, critical assessment of various metaheuristic techniques which utilized in cell formation problem solving is made through extensive literature review. Various existing models for cell formation are argued consequently and directions for future work are presented. 

A set partitioning based heuristic procedure for incremental cell formation with routing flexibility

One of the important issues regarding the implementation of cellular manufacturing relates to deciding whether to convert an existing job shop into a cellular manufacturing system comprehensively in a single go, or to convert in stages incrementally wherein the cells are formed one after the other taking the advantage of experiences of implementation. In this paper, a heuristic method based on iterative set partitioning is proposed for incremental cell formation where part operations can be processed on alternative machines. The objective is to minimize cycle time for a given number of workstations. The proposed method is numerically compared with the existing branch and bound technique and another heuristic algorithm based on multistage programming. It is found that the proposed method requires significantly less computational efforts to yield the optimal solution.

Human related issues in manufacturing cell design, implementation, and operation: a review and survey

The application of cellular manufacturing in batch-type environments is a well-known manufacturing strategy that typically improves manufacturing efficiency by utilizing the philosophy of group technology. It is also important that for the successful implementation of cellular manufacturing, that one focuses both on technical issues (cell formation and design) and human issues. Unfortunately, human issues are typically not examined as rigorously as often as technical issues. This paper presents an overview and evaluation of the diverse range of human issues involved in cellular manufacturing based on an extensive literature review. Further, a survey to determine the importance of eight different human issues in cellular manufacturing was administered to a sample of academics, managers, and workers involved in cellular design and implementation results are presented and discussed.

Performance of Fuzzy ART neural network and hierarchical clustering for part-machine grouping based on operation sequences

The problem context for this study is one of identifying families of parts having a similar sequence of operations. This is a prerequisite for the implementation of cellular manufacturing, group technology, just-in-time manufacturing systems and for streamlining material flows in general. Given this problem context, this study develops an experimental procedure to compare the performance of a fuzzy ART neural network, a relatively recent neural network method, with the performance of traditional hierarchical clustering methods. For large, industry-type data sets, the fuzzy ART network, with the modifications proposed here, is capable of performance levels equal or superior to those of the widely used hierarchical clustering methods. However, like other ART networks, Fuzzy ART also results in category proliferation problems, an aspect that continues to require attention for ART networks. However, low execution times and superior solution quality make fuzzy ART a useful addition to the set of tools and techniques now available for group technology and design of cellular manufacturing systems.

Productivity gains by cellular manufacturing

This paper discusses some of the major factual results and discussions of the effects of implementation of a cellular manufacturing environment on the productivity of people, management and facilities, as was experienced in this study. It is suggested that significant improvements at very low costs are possible at managerial, and other work force levels, by introduction of appropriate production management systems. This is based on analysis of the changes in production costs and more importantly the behaviour of employees brought about by a first time implementation of cellular manufacturing in a company.

Performance obstacles in cellular manufacturing implementation— empirical investigation

Performance obstacles in cellular manufacturing implementation— empirical investigation

Performance obstacles in cellular manufacturing implementation— empirical investigation

AbstractPerformance obstacles are factors in the work environment that restrict productivity by inhibiting workers in the execution of task responsibilities. It is thus crucial to identify and reduce those obstacles for more effective cellular manufacturing implementation. This article describes research carried out in 4 Korean manufacturing plants to investigate performance obstacles in cellular manufacturing implementation. The results of the research reveal several important factors in cellular manufacturing implementation: training and education, information, teamwork skill, supervision, and scheduling. This research discusses human and organizational factors in new manufacturing system implementation and reveals that those factors play a central role in the implementation. © 2002 John Wiley & Sons, Inc.

The impact of management and employees on cellular manufacturing implementation

Several empirical studies have dealt with the impact of cellular manufacturing (CM) on employees’ attitudes, job satisfaction, morale, and quality of work life. While the understanding of the impact of CM on these characteristics allows practitioners to identify the undesirable effects to avoid during CM implementation, research is lacking on which desirable sociotechnical job characteristics have significant impacts on the success of CM implementation. This study uses the sociotechnical system (STS) principles to identify three major categories of variables that are likely to impact CM implementation namely top management role, job design for operators, and cross training. Three different exploratory regression models were used to identify subsets of the variables that have the most impact on CM success. The results indicate, among other things, that CM implementation seems to be more successful if top management initiates the CM project, and if employees are cross-trained to run various machines and read blue prints. In addition, CM success seems to be enhanced if jobs are scheduled and tracked within the cells.

Sequence-dependent clustering of parts and machines: A Fuzzy ART neural network approach

This study addresses the problem of identifying families of parts having a similar sequence of operations. This is a prerequisite for the implementation of cellular manufacturing, group technology, just-in-time manufacturing systems, and for streamlining material flows in general. A pattern recognition approach based on artificial neural networks is proposed, and it is shown that the Fuzzy ART neural network can be effectively utilized for this application. First, a representation scheme for operation sequences is developed, followed by an illustrative example. A more comprehensive experimental verification, based on the mixture-model approach is then performed to evaluate its performance. The experimental factors include size of the part-machine matrix, proportion of voids, proportion of exceptional elements, and vigilance threshold. It is shown that this neural network is effective in identifying good clustering solutions, consistently and with relatively fast execution times.

A methodology of implementation of cellular manufacturing

This paper proposes a methodology of implementation of cellular manufacturing. This methodology integrates into a logical routine the series of methods and activities that characterize the implementation of cellular manufacturing in typical operations systems. The methodology has been designed and refined along an action research project in a toy manufacturer in South Brazil. The results suggest that its application may successfully co-ordinate the implementation of manufacturing cells in a team-based approach, and subsequently improve people's knowledge about the process of continuous improvements in operations.

Evaluating Virtual Cells and Multistage Flow Shops: An Analytical Approach

The implementation of cellular manufacturing can be carried out through the creation of manufacturing cells (i.e., groups of dissimilar machines dedicated to a set of part types that are placed in close proximity to one another) or virtual cells (i.e., the dedication of specific machines within the current departments to a prespecified set of part types). Typically, the former involves the reorganization of the shop floor and provides the operational benefit of reduced materials handling. On the other hand, the latter configuration is simpler to implement and easier to reconfigure in light of product demand changes, but it may not offer the same operational benefits. In this paper, we propose and validate analytical approximations for comparing the performance of virtual cells and multistage flow shops. Using these approximations and hypothetical data, we identify some key factors that influence the implementation of virtual cells in a multistage flow shop environment. We conclude with an application of our approximations to industrial data.

A framework for measuring success of cellular manufacturing implementation

This paper analyses a part of the data collected in a survey of US firms that operate manufacturing cells. The paper identified two underlying dimensions or constructs that explain the relationships amongst the performance measures commonly used to assess the relative magnitude of success of cellular manufacturing (CM) implementation. These are: (1) delivery response (D R), and (2) quality-cost (QC). Scrap-rework and throughput time were identified as appropriate surrogate measures respectively for QC and D R, indicating that those two variables may suffice to monitor success of CM implementation. The firms report significantly greater improvements in D R variables than they do in QC. The paper also proposes a methodology to categorize relative success of CM implementation. Noting that no manager would volunteer to categorize his implementation efforts as a failure, the categorization scheme proposed can be utilized regardless of the firm's claims. Interpreting success within the framework of the proposed classification scheme, further analyses show that plants with a large number of product lines or operating a large number of cells tend to be more successful than others. However, the degree of success of CM implementation does not seem to be impacted by cell independence or whether the plant is unionized or not.

An Alternative Framework for the Design and Implementation of Cellular Manufacturing

Presents an alternative framework to resolve the initial problems encountered in implementing a cellular manufacturing (CM) project. There are not a large number of case studies available detailing the same. The main thrust is on identifying some of the problems which arose in implementing a CM project at Otis Engineering, a business unit of Halliburton Corporation located in Carrollton, Texas. The project was implemented at one of Otis′s four plants and only the product line manufactured by that plant was considered. The extensive literature on scheduling in CM was drawn on to resolve problems in reducing set‐up times and increasing throughput. Set‐up‐time reduction, process capability, operator training and scheduling strategies were deemed to be critical to the successful operation of the cell.

Manufacturing system cell formation and evaluation using a new inter-cell flow reduction heuristic

The initial stage in the implementation of cellular manufacturing involves the determination of part families and machine cell (PF/MC). We developed a new heuristic for PF/MC formation that provides a variety of PF/MC alternatives. In addition, we developed a simulation model of a group technology (GT) system using the new heuristic and compared this to that of a traditional process layout (TPL) system. We used performance criteria such as: machine utilization, queue length, flow time, etc. The simulation experiment included a TPL shop, an original GT shop, and an alternative GT shop, each with different part demand distributions.

From machine‐centered to human‐centered manufacture

AbstractThis article provides a case study analysis of the process of transition from a traditional machine‐centered job‐shop working environment to a human‐centered manufacturing facility at a hardware fabrication plant in South Australia. The origination, design, and implementation of cellular manufacturing is examined, and the consequences of change for the organization and control of work is critically appraised. Employees operating under the new system take greater responsibility for their work performance and positively appraise the practice of cellular manufacture.

The human factor in cellular manufacturing

AbstractRecently, Group Technology (GT) as a batch manufacturing innovation has commanded much research attention and pragmatic interest. This approach to small lot production is based on identifying and exploiting similarities. By grouping items which share common traits, GT facilitates the rationalization of activities in a wide variety of functional areas including purchasing, design, and manufacturing. When GT is used in manufacturing one potential application involves the creation and operation of production cells. A production or manufacturing cell is a group of functionally dissimilar machines that are placed together and dedicated to the manufacture of a specific range of component parts. The usefulness of cellular manufacturing is demonstrated by the impressive catalog of benefits reported by its users both in the US and abroad. Reductions in work‐in‐process and finished goods inventories, decreases in production lead time, better delivery performance, improved product quality, and an overall increase in productivity are but a few of the benefits reportedly accruing to the use of cells.While it appears that cellular manufacturing can significantly improve the operation of batch production, an important component of the GT cellular production system has, unfortunately, been overlooked. Little study has been devoted to the human aspects of the use of production cells. The research reported in this paper attempts to fill this void by systematically examining the effect of cellular production on batch manufacturing employees. The research site was a medium size plant in which a portion of the functionally arranged facilities had recently been converted to a cellular layout. Both functional and cellular workers responded to a questionnaire designed to assess employee perceptions of their jobs, their job satisfaction, and their performance. In contrast to the findings of earlier (ethnographic) studies, cellular manufacturing employees did not perceive greater autonomy, significance, identity, or cohesiveness in their jobs than workers in traditional functional jobs. Cell workers also were as satisfied with their jobs, supervision, and advancement opportunities as non‐cell workers, but were more satisfied with their pay. Supervisory ratings of performance did not vary between groups.The major contributions of this article are threefold. First, this research represents the first attempt to scientifically evaluate the human impact of cellular manufacturing. Second, in contradicting the findings of earlier descriptive studies, all of which emphasize the very positive human consequences of cellular production, the need for additional research which challenges initial intuitive presumptions is clearly indicated. Third, and perhaps most importantly, the findings of this exploratory study suggest that cellular manufacturing does not have a negative impact on worker performance, attitudes, or satisfaction. A ramification of this is that reductions in work‐in‐process and finished goods inventories, decreases in production lead time, and improved overall productivity which reportedly accompany the implementation of cellular manufacturing may be achieved without any human fallout.

A review of cellular manufacturing assumptions, advantages and design techniques

Abstract For years the industrial job shop has faced an increase in complexity and a decline in productivity due in part to an increase in part mix, volume of parts, plant size, machine production rates, and part complexity. One result of the increased complexity and reduced productivity is the development of Group Technology and cellular manufacturing which seek to eliminate or minimize complexity and to improve or maximize productivity. Group Technology can be defined as bringing together and organizing (grouping) common concepts, principles, problems, and tasks (technology). Cellular manufacturing is the physical division of the functional job shop's manufacturing machinery into production cells. Each cell is designed to produce a part family. A part family is defined as a group of parts requiring similar machinery, machine operations, and/or jigs and fixtures. The parts within the family are normally transformed from raw material to finished part within a single cell. For the successful implementation of cellular manufacturing, a set of assumptions should be adhered to. These assumptions are related to the design, operation and control of the system. There are numerous advantages associated with cellular manufacturing: • -Reduced material handling • -Reduced tooling • -Reduced set-up time • -Reduced expediting • -Reduced in-process inventory • -Reduced part makespan • -Improved human relations • -Improved operator expertise. There are also some disadvantages associated with cellular manufacturing: • -Increased capital investment • -Lower machine utilization. Numerous techniques are available to configure or reconfigure a cellular manufacturing system. Interestingly, nearly all published techniques come from Great Britain and Europe. Mitrofanov, in Russia, was an early proponent of cellular manufacturing with his composite component approach. J. L. Burbidge's Production Flow Analysis (PFA) was one of the first methodologies developed and subsequently published in the free world. It is also probably the most well known and most widely accepted method. In the last few years, Burbidge's PFA has undergone considerable revision and updating in an attempt to eliminate much of the original manual sorting and calculations. Computerization has been applied in an attempt to determine the key machines. Burbidge has termed this new concept nuclear synthesis [4]. El-Essaway and Torrance incorporated many of Burbidge's material flow simplification concepts in their computerized Component Flow Analysis. V.B. Solaja and S.M. Urosevic have developed a method in which cells are designed based on optimizing three criteria: Maximizing machine utilization, minimizing the part operation time, and minimizing capital invested. In 1972, McAuley presented a method of creating cells based on part classification and coding and on a similarity coefficient. A.S. Carrie and J. Mannion reported in 1975 on a cell design procedure which is based on forcing the cell to resemble a flow shop. There have been several other design techniques presented in the open literature. Each technique has specific capabilities and limitations. In summary, there are numerous techniques developed to form a traditional job shop into a cellular manufacturing system. But, there are very few documented applications or techniques based on optimal seeking analytical development. It is apparent that although techniques are known, they have not been developed for easy industrial application and in many cases do not have a strong enough analytical base to warrant implementation. Therefore although obvious advantages to Group Technology and cellular manufacturing exist and methods to create a cellular manufacturing system are available, these methods are problematic because design or redesign of a job shop to a cellular manufacturing system remains rather difficult and theoretical.