الزامات و روش تعادل احتمالات برای برنامه ریزی تولید در سیستم های مورد استفاده مونتاژ تولید

The subject matter of that paper is to plan the method of concurrent multi-assortment rhythmic production realised in manufacturing assembly enterprises. The outworked method putting an emphasis on effective utilisation of system resources taking into consideration the synchronising role of its bottlenecks. The process of the making of the planning decision flows simultaneously with the procedures generating process of the distributed control of the resources work in the system. Comparing with the hitherto researches the originality of the requirements and possibilities balance method (RPBM) is the described production type enabling tasks realisation in the exclusive-like mode and also in the rendezvous-like mode, which is characteristic for assembly processes.

Surrounding reality is actually characterised by very fast rate of the progressive changes. That stuff, which was modern, original and unknown yesterday, is the generally used standard today and will be obsolete and squeeze out by another, better, faster or user-friendlier solution tomorrow. The sudden development of technique, technology, automation and computer science has caused the removal of the time and spatial barriers contributing to the progressive process of globalisation. The present-day customer being able to compare easily a purchase offer made to her/him with the competing firms propositions, is very demanding and her/his needs and preferences are subject to continual modifications what in the obvious way determines the activity of enterprises. The production strategies of the contemporary enterprises have been essentially changed by their customer oriented activity, the fast reaction to demand changes and requirements of the marketing strategies. Recently another strong tendency in industry to produce complicate products in variant forms, differing from each other with single elements or whole sub-assemblies is observed. Manufacturing assembly enterprises produces that kind of products. In the manufacturing assembly systems (Fig. 1) manufacturing processes at manufacturing resources (i.e. machine tools) and assembly processes at assembly resources (i.e. robots, manipulators) are realised. Assembly processes can represent different percent of total production processes realised in the plant, dependent on industrial trade and the kind of the final products [1]. However, many producers deal only with assembly what can be observed in promptly developing branches of industry such as car, audio-video and computer ones. Elements for assembly are often bought by competing firms at the same suppliers, that is why rate, costs and quality of assembly decide about competitiveness of a given enterprise.An interest of the issues of the production organisation in the manufacturing assembly systems working in changeable environment results from those premises.

The considered research problem boils down to balance the customer requirements with limited producer possibilities. In order to describe them in mathematical way, the two-part production flow model has been formulated. That model is divided into: the system model for the disposition of the producer and production order model focused on the customer requirements. The checking of the qualitative sufficient conditions is needed for defining whether production flow in the system is possible. However, the checking of the quantitative sufficient conditions enables to answer the question whether the new production order can be terminable realised in the given production system. The fulfilment of all checked sufficient conditions is adequate to the permissible solution finding. That solution is a basis of the production plans and the procedures controlling the resources work in the system. The synthetic depiction of the outworked method is presented in Fig. 14.On the basis of the authority method original software has been outworked and its correctness has been verified. Thanks that the practical application of RPBM in the manufacturing assembly enterprises is possible. The entering of the system and production order data into the computer system is necessary. An exemplary computer form with the input data in Fig. 15 is presented.The input data are transformed by the computer system and then the final results are generated as the final reports and the Gantt's chart showing the planed resources occupations (Fig. 16). The output data generated by the software adding the producer in the area of the production planning (production order acceptation or rejection) as well as production control, because they include ready procedures of the distributed control of the resources work in the system [8].The computer system outworked on the basis of the RPBM works almost on-line that is advantage comparing with the commercial systems. That system can be used in the customer service facility like the element, which works together with the ERP class system. Moreover, the outworked computer system enables to define the adequate system structure with known production orders structure. Because of that it is helpful for solution of the research and simulation tasks. In comparison to other known methods the most important advantages of the RPMB and the software formed on its basis are as follows: simplicity of the approach using the algebraic model, short time of the results generating and low costs of the practical implementation. The RPBM is useful for multi-assortment rhythmic production with short cycles realised in small batches in the manufacturing assembly systems determined by their constraints and dealing in changeable environment. The elimination of the manufacturing or the assembly part of the method does not influence the correctness of its working, because of the model versatility. Therefore, that method application in the system dealing with only assembly as well as manufacturing is possible.