摘要:

We develop a classification scheme and taxonomy of operating decisions in flexible manufacturing systems (FMS). The taxonomy is used to identify a promising research area termed General FMSs (GFMS), where very little academic work has been reported to date in the prior literature. A decision framework for the development of tool loading and shop floor control policies in GFMS is also presented, and used to highlight specific future research directions. Strategic justification for developing operating policies for the GFMS classification is also provided.

ISSN:0020-7543    

DOI:10.1080/00207549408957080

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Correct part orientation has been the key to many successful automation applications, and often vibratory bowls were used. Traditionally, the design and tooling of the vibratory bowls are limited to a group of skilled experts. In this paper a feature-based framework for the automatic selection and sequencing of orientating devices is presented. A direct link between part representation and the selection and sequencing of modular orientating devices is provided by a spatial technique, in place of traditional CAD representation. Also described is the classification of a part's orientating features and classification of orientating devices. These two classifications are integrated into a knowledge-based system that will automatically generate sequences of modular orientating devices.

ISSN:0020-7543    

DOI:10.1080/00207549408957081

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

We examine the design of flexible welding machines, particularly the process of matching a group of components with an optimum machine design. Analysis of current design methods highlighted the need for a systematic and less time consuming method for the conceptual design of these machines. Also identified was the need to establish a link between components to be manufactured, and the design of welding machines, within appropriate economic constraints. We present the Attribute Design Method, developed to achieve an optimum machine design for a given group of components. The method is applied to the design of a flexible welding unit, but its application may be extended to the design of flexible manufacturing systems.

ISSN:0020-7543    

DOI:10.1080/00207549408957082

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The problem of scheduling in flowshop and flowline-based manufacturing cell is considered with the bicriteria of minimizing makespan and total flowtime of jobs, The formulation of the scheduling problems for both the flowshop and the flowline-based manufacturing cell is first discussed. We then present the development of the proposed heuristic for flowshop scheduling. A heuristic preference relation is developed as the basis for the heuristic so that only the potential job interchanges are checked for possible improvement with respect to bicriteria, The proposed heuristic algorithm as well as the existing heuristic are evaluated in a large number of randomly generated large-sized flowshop problems. We also investigate the effectiveness of these heuristics with respect to the objective of minimizing total machine idletime. We then modify the proposed heuristic for scheduling in a cell, and evaluate its performance.

ISSN:0020-7543    

DOI:10.1080/00207549408957083

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

New manufacturing technologies and philosophies such as group technology, flexible manufacturing systems, just-in-time, and robots have emerged in recent years. Manufacturing facilities which utilize these technologies and philosophies require new models and solution methodologies to address their design and operations. One of the design activities in modern manufacturing facilities is determining machine arrangement on the facility floor. This activity involves several details of the facility and interacts with several of its functional areas. Further, machine layout has some features which distinguish it from the block layout problem. As a consequence, existing layout procedures which concentrated on developing a block may not be directly applied to machine layout, and new models and solution procedures are required. This paper reviews the machine layout problem in modern manufacturing facilities, and addresses design issues of machine layout and the suggested optimization approaches for developing the layout. Potential areas for research are also suggested.

ISSN:0020-7543    

DOI:10.1080/00207549408957084

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

We introduce here a framework for the evaluation of material flow system models diagnosis of model performance problems, selection of model improvement actions and the implementation of these actions. Many of the actions in this model evaluation and redesign process cannot be modelled through specific procedures. Whenever this is the case we encourage the involvement of the designer by providing decision support, e.g. in determining whether the model performance is actually met and in selecting model improvement actions. In situations in which design tasks can be automated, the framework allows the integration of design tools that can take over these tasks. We present strategies for addressing tasks within the evaluation and redesign process as well as their implementation. The concepts presented are implemented in a design workstation for material flow systems.

ISSN:0020-7543    

DOI:10.1080/00207549408957085

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The digitization of mathematically unknown free-form curves is frequently required. Current industrial practice relies on the experience of an operator to determine the direction of a CMM probe's approaching vector and the number of samples to represent a complex curve. An automatic procedure is proposed to generate recursively the approaching vector direction as well as the sampling rate. Several techniques including a linear prediction, a polynomial prediction, and a spline interpolation method have been presented and compared. Experimental results show that the spline interpolation method provides the best digitization accuracy and requires the least number of sampling points.

ISSN:0020-7543    

DOI:10.1080/00207549408957086

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

We present a new approach to scheduling Flexible Manufacturing Systems based on Response Surface Modelling methodology. This experimental technique for model building is used to generate scheduling rules which are then used by the machines in the process of job selection. A systematic procedure to identify factors of interest and utilize them to develop a scheduling mechanism is presented. Issues of automation revision of the rules to adapt to changes in the shop are also discussed. The approach was tested as part of a larger framework of distributed decision making for scheduling and was found to perform significantly better than static heuristic procedures.

ISSN:0020-7543    

DOI:10.1080/00207549408957087

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

To support the production rate, some transfer line stations with long cycle times must be duplicated. A job is processed in only one of the duplicate stations. If laid out in parallel, this duplication essentially doubles the capacity, but, for practical reasons, these duplicate stations are often laid out in a series. The serial layout has a capacity less than the parallel's, and also raises some operational questions. We enunciated and analysed this actual problem of operating duplicate stations in series. We simulated an existing closed-loop transfer-line with duplicate stations in series using the actual failure and repair characteristics of the automated stations, and compared a new heuristic with three simple policies.

ISSN:0020-7543    

DOI:10.1080/00207549408957088

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

An approximate method for the performance analysis of a particular flexible manufacturing system with unreliable machines and a circular conveyor consisting of a fixed number of cells is presented. Workpieces are transported among the machines on the conveyor. We assume that the time to failure and the time to repair are exponentially distributed. Our analysis is based on the service completion time of the workstations, which leads us to find the system time. We have developed a decomposition method that analyses each workstation in isolation. The performance measures of our interest include the mean system time, the mean number of workpieces in the system, the probability that a cell is occupied by a workpiece and the conveyor's throughput. Experimental results show that the approximate method is highly accurate.

ISSN:0020-7543    

DOI:10.1080/00207549408957089

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor