摘要:

There is a growing demand for integrated manufacturing systems in the sense that the normally separate parts of an enterprise could share common resources and goals. However, such systems should be highly adaptable in response to changing needs. One way forward in coping with high levels of complexity and change is to use a formalised and structured approach which straddles design, implementation, run-time and maintenance phases of such systems thereby enabling reconfigurabihty over the system life cycle. Such an approach will ensure clarity, consistency, accuracy and re-utilisation of knowledge and information among the different phases. This paper reports on a methodology conceived to facilitate life cycle support for integrated manufacturing systems and the software toolset which has been developed to support implementation, run-time and change processes, the toolset combines the use of IDEF0(for activity based modelling), 1DEF1x(for entity-attribute relationship modelling) and EXPRESS (for data modelling).

ISSN:0020-7543    

DOI:10.1080/00207549608904888

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Models of manufacturing flexibility have become centred on highly automated systems. These fail to account for the flexibility that is characteristic of many small, human-centred manufacturing operations or in systems based on hybrid automation. This paper presents a generic framework that models flexibility in terms of the underlying capability of a manufacturing system and its control systems, human and machine. In this model, manufacturing versatility, the ability to change, is realized through the application of automatic control to the inherent capability of the system. Flexibility defined as the ability to cope with the uncertainty of change, extends versatility through the application of intelligent control. This process generates new knowledge about the system and its environment. The system learns by applying this knowledge and consequently the autonomic response of the system is dynamically improved. The model is hierarchical, accounting for capability, versatility and flexibility at various levels of manufacturing system, from the operator-machine level up to a whole organization. The efficacy of the model is demonstrated in a study of a semi-manual assembly cell in a small manufacturing company.

ISSN:0020-7543    

DOI:10.1080/00207549608904889

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

A batch process plant consists of individual plant items linked by a pipe network through which product is routed- During the operation of the plant, the availability of each item for configuration of process routes is severely constrained by the structure of the network, and the current arrangement of the valves which control the routeing. Current approaches to short term scheduling contain simplifying assumptions which ignore these constraints and this leads to unrealistic and infeasible schedules. This paper describes work done towards the development of a hybrid system, the batch process scheduler (BPS), which uses techniques from the areas of artificial intelligence (AI) and discrete event simulation (DES) in order to overcome these simplifying assumptions and develop good schedules which can be implemented in a plant.

ISSN:0020-7543    

DOI:10.1080/00207549608904890

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This paper presents a solution to the multiple-level, capacitated resource problem of determining container sizes, number of kanbans, and product sequence in a just-in-time (JIT) shop with kanbans. Previous research has looked at these issues independently, but this is the first paper that provides an integrated approach which addresses all three of these problems simultaneously. The solution procedure described in this paper is called JACKS (JIT Algorithm for Containers, Kanbans and Sequence), and it is based on an algorithm published previously by the authors for solving the economic lot scheduling problem referred to as the method of prime subperiods (MOPS). MOPS is used to determine container sizes and product sequence at a stage of the production process that processes all products (e.g. the final stage), and then JACKS is employed to determine feasibility and the number of kanbans at other stages. Feasibility is guaranteed, and the algorithm attempts to drive costs as low as possible, although optimality is not assured. The solution approach, based on a depth-first, branch-and-bound search, is demonstrated via an example shop.

ISSN:0020-7543    

DOI:10.1080/00207549608904891

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Companies are increasingly being forced by market demands to increase the competitiveness of their products in regard to price, quality and delivery time. Development, both of product and production, is the key word in achieving this goal. This paper focuses on the following related subject: cost-effective design, with applications to robotic assembly cells. Against this background, a total productivity model is introduced, which allows an opinion to be formed about the performance of robotic assembly cells during the conceptual stage of the design process.

ISSN:0020-7543    

DOI:10.1080/00207549608904892

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Vehicle selection and dispatching are an essential part of an AGV dispatching rule. In this paper, single-attribute AGV dispatching rules are re-examined and various multi-attribute dispatching rules are proposed. Single and multi-attribute dispatching rules are compared for selected performance measures such as queue length and load waiting time in each department, vehicle travel time, and job completion time. The superiority of the multi-attribute dispatching rules is demonstrated for these measures.

ISSN:0020-7543    

DOI:10.1080/00207549608904893

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The complexity of a tool's simultaneous movement in five axes increases the difficulty of evaluating surface error in 5-axis machining. This paper presents an error analysis method for 5-axis machining which applies differential geometry techniques to evaluate the cusp height between adjacent cutter locations. Effective cutting shapes of adjacent cutting positions are derived. The technique of finding cusp height is also proposed. A method of finding the direct and indirect intersection positions is presented to evaluate the surface error. The error analysis method proposed in this paper can be used to improve the efficiency of 5-axis machining and to generate appropriate cutter path distribution. Analytical results and examples of practical applications are also presented.

ISSN:0020-7543    

DOI:10.1080/00207549608904894

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This paper is concerned with the performance of alternative dampening procedures to cope with system nervousness in manufacturing firms that employ a material requirements planning (MRP) system. It presents three dampening procedures to reduce rescheduling frequency of open orders. These procedures arc compared using a simulation study. The results indicate that the performance of a dampening procedure depends upon the operating environments of manufacturing firms. The results also show that the reduction of system nervousness, as measured by the frequency of schedule disruptions, does not necessarily lead to a better system performance. It is the appropriate employment of a dampening procedure and lot-sizing rule that can contribute to the system improvement.

ISSN:0020-7543    

DOI:10.1080/00207549608904895

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This paper presents anew classification system for shearing operations and concepts are developed for extracting entity groups, recognizing them, and characterizing shearing features for sheet metal components in two dimensional (2-D) layout. Features are recognized by studying the wireframe representation of the layout and a set of principles are derived to relate the features geometrically and topologically. Features which form potential candidates for CAPP systems are determined based on the new classification system. This helps in the development of many alternative process plans in general and selection of an optimum process plan based on constraints in particular. Features recognized along with geometrical information can be used in codification of parts, optimization of tool path, for mapping the features for tools to manufacture, inspection, etc.

ISSN:0020-7543    

DOI:10.1080/00207549608904896

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In this paper, simulation in conjunction with Petri net modelling will be used to improve decision making in manufacturing control systems.

ISSN:0020-7543    

DOI:10.1080/00207549608904897

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor