Computer-aided Production Planning Research Articles

PRIMENA KONCEPTA INDUSTRIJA 4.0 U REPUBLICI SRBIJI

Četvrta industrijska revolucija označava promenu u industrijskom sektoru: sve se razvija iz pred-planiranog i sekvencijalnog procesa u organizacioni, samoorganizovani logistički sistem. U ovom radu biće prikazano istraživanje trenutnog stanja primene koncepata Industrije 4.0 u Republici Srbiji. 12,6 procenata predeuzeća iz prerađivačkog sektora je uvelo tehnologije industrijskih robota, 31,6 procenata je uvelo tehnologije računarom podržano planiranje i upravljanje proizvodnjom.

Computer aided production planning - SWZ system of order verification

SWZ (System of order verification) is a computer implementation of the methodology that support fast decision making on the acceptability of a production order, which allows to determine not the best possible solution, but admissible solution that is possible to find in an acceptable time (feasible solution) and acceptable due to the existing constraints. The methodology uses the propagation of constraints techniques and reduced to test a sequence of arbitrarily selected conditions. Fulfilment of all the conditions (the conjunction) provides the ability to perform production orders. In the paper examples of the application of SWZ system comprising the steps of planning and control is presented. The obtained results allowing the determination of acceptable production flow in the system - determination of the manufacturing system parameters those that ensure execution of orders in time under the resource constraints. SWZ also allows to generate the dispatching rules as a sequence of processing operations for each production resource, performed periodically during the production flow in the system. Furthermore the example of SWZ and simulation system integration is shown. SWZ has been enhanced with a module generating files containing the script code of the system model using the internal language of simulation and visualization system.

Computer-aided process planning based on automatic fuzzy comprehensive evaluation

There is strong contradiction in the traditional evaluation of processes in terms of diversity of manufactured goods, discreteness of manufacturing processes, complexity of the environment of manufacture, and variability of the market. It is essential to meet the need for an automatic, time-saving, accurate, and optimal evaluation of processes. The current study was aimed at fuzzy auto-evaluation, taking the processes for the parts as (a) subject investigated, (b) structuring evaluation system, and (c) method of processes in computer-aided production planning (CAPP) based on fuzzy mathematics. On analysis and comparison, the automatic fuzzy comprehensive evaluation system was built based on the following factors: set, the weight set and assessment set, and the single factor: proposed comprehensive fuzzy evaluation. The membership degree was determined with fuzzy statistics, and the weight of various factors was determined by the fuzzy consistent matrix. A combination of theoretical analysis, practical experience, goals of evaluation, and factors set for processes was accomplished by extracting the factors that impacted evaluation of processes; weight set was established based on different weights that each factor impacting on the extent of technology programs gave; the assessment set was gained with a factor matrix which the expert group provided for every factor; the fuzzy evaluation matrix was obtained with a matrix calculation according to the model M (∧, ∨). The process grade was determined according to the principle of maximum membership degree. The process evaluation would automatically be realized through the evaluation system with the VC++ program after weights of various factors from the experts in the field were added. The optimum process was eventually obtained by comparing the grades of these processes. Three feasible processes of a disc-like component, as an example, were evaluated through this evaluation system, realizing the automatic evaluation of processes and obtaining the best process.

Selection and implementation of a PPC system

There are many computer-aided production planning and control (PPC) systems available on the market which can provide a solution to the complex task of production planning and control. However, the question remains, how can a company find an optimal system from the vast amount of available systems? This article proposes that a company, having decided to buy one of the available systems, starts a project for selection and implementation of the PPC system.

Data modelling with IDEF1x

The idea of integrating business, product development, and manufacturing activities has gained momentum in manufacturing industry. To remain competitive, companies must optimize the utilization of their resources. This integration of various functional areas, e.g. computer-aided design, computer-aided process planning, computer-aided production planning and control, computer-aided quality control, and computer-aided manufacturing requires a large volume of data to be stored by the users contributing to those areas. IDEF1x provides a formal framework for consistent modelling of the data necessary for this integration. This paper provides insights into the IDEF1x modelling technique. The paper concludes with a discussion of several relevant research issues.

Production planning systems with AI philosophy

In this article we present our experience with the development of several systems for computer-aided production planning. The real life production planning tasks can be decomposed into two steps. The latter is the scheduling task, including resource allocation, which must conform to rules, created in the former step. They describe technological conditions that are specific for the manufacturing domain and the factory organization. Thus, the production plan may be viewed as a set of rules that may be considered as constraints for the scheduling task. We focus our analysis on the problem of how to specify these rules. We also show how these plans as manufacturing instruction sequences are structured for diverse production goals. A brief survey of the systems the authors have developed is given as well.

System Integration and Technological Database - A Contribution to Concurrent Engineering

Computer aided production planning (CAP) tools ranging in the departments of technical production planning are most of all the interface between product design and carrying out the process itself. Nowadays development tends to Concurrent Engineering which is linked with a deeper system integration. Appreciate development results of computer aided process planning can essentially support this trend. Manufacturing data, in particular, represent a special bottle-neck, in this case. That means, we have to find out creative approaches especially for this data type. The author demonstrates a method to solve this problem by means of a technological database.

Features of production planning and control in China

This paper focuses upon the situations and features of computer aided production planning and control in China: 1.(1) The production planning must be divided into several levels,2.(2) mrp usually only generates work order requirements planning and purchasing part planning which are assembly requirements,3.(3) the method of controlling work-in-process stock is used for repetitive manufacturing,4.(4) planning horizons are calendar year, quarter, month and decade of the month,5.(5) the systems must resort to Chinese characters processing.

Trade Union Technology Policy between the Protection of Status and Work Structuring

This article deals with the consequences of rationalization in the field of labour policy brought about by information technologies as well as their impact on the trade unions' planning policies. The West German machine-building industry has been chosen as the empirical field for studying this new type of rationalization and control strategies, 'computer-aided production planning and production control'. This study shows that the overall labour process in companies is less characterized by a consistent 'novel' production concept as detailed in Kern and Schumann's recent analysis of the 'end of division of labour'; labour relations and utilization of labour rather seem to be regulated by a multitude of variants in the field of labour policy. Centralized control and freedom to decide and act on the part of decentralized units in companies may complement one another. Above all the process of implementing information technologies (project manager/project planning) and the dependence of the technological and social resourcefulness of these systems on human knowledge and abilities must be considered as factors of wide-ranging importance for fields of policy and negotiation, modes of regulation and industrial relations which have been established in a company. This novel state of affairs especially demands a better understanding on the part of the trade unions of fields of policy and new bodies responsible for these policies in the companies.

Computer Aided Production Planning (CAPP) Systems and Approaches

This paper deals with the developments in the field of Computer Aided Production Planning(CAPP) Systems. It reflects the importance of using computer techniques in manufacturing, available systems descriptions and their basic requirements. The process planning of a part requires many deals of data input and output information. Manually planning requires a skilled planner and involves tedious calculations. It is slow and error prone, involves big effort, with limited information. Also the manually planned sheets are frequently inconsistent and incomplete. The existing systems of CAPP show the creation of simplified operation technique, saving in planning time and costs and reduce the skill required.CAPP assists the user to more efficient use of the drawing information, access manufacturing information and promotes the effective use of this information. Moreover the manual procedure does not integrate well with CAD/CAM systems, thus there is a strong incentive to automate the procedure, particularly if the planning time and cost can be reduced. CAPP systems, therefore, provide possible solutions to the technological problems in addition to solving the geometrical part of the production task.