COMPUTER SYSTEM DESIGN

Computer System Design

Computer System Design

Introduction

Integration in international production networks, short time-to-market, more individual solutions and short product life-cycles determine the competitive situation for the European industry towards the end of the 20th century. Stiff organizational structures with large hierarchies, built from a functional understanding of industrial production are no longer suited for the task of surviving in the market. Business process re-engineering has attracted a lot of interest, especially the idea of radically introducing new process oriented structures. However, experience shows that a single deep cut is sometimes not only very dangerous for the company, but also underestimates the necessity of continuous adaptation. An overall approach is needed that allows living with the changes and adapting processes wherever and whenever needed.

Today's manufacturing technology already offers solutions for flexible production and assembly systems that allow production of tailored products at low costs. However, the reduced product life-cycles require adjustment of even these systems and the production flow at short intervals. This adaptation can only be achieved efficiently if the business processes dealing with factory planning are optimized. While new organisational concepts create more flexibility for resource allocation, powerful tools are needed to design and evaluate new structures. An approach to process redesign has to consider organisational aspects as well as an appropriate support with information technology.

The design and redesign of manufacturing systems, summarized here as manufacturing system engineering (MSE), is an important part of the factory planning process. It is a complex, multi-disciplinary process that involves not only people located at different production sites, but also a variety of tools that support special subtasks of the process. Solutions developed for subsystems by different designers have to be integrated into a single solution. Modelling tools must therefore assist in managing complexity and allow observation of the system model from different points of view.

In our approach we consider layout planning, arrangement of machines, material and information flow planning, capacity evaluation as well as the definition of the production organisation part of MSE. Surprisingly the investigation of the state-of-the-art in this field reveals that neither widely accepted methodologies nor a satisfying computer support exists. In contrast with the requirements, many companies follow their own practice, often grown over many years and use a variety of tools that are in many cases poorly integrated. There are only a few approaches to define broader consistent models [K. Mertins, M. Rabe, S. Könner, 1995]. As a result, the process is slow and error prone and endangers the competitive position of many European enterprises.

Considering this situation, we address the integration task from the analysis of the engineering process. Starting with the definition of integration requirements, we design a new process that is founded on information system support and relies on simulation for manufacturing system evaluation.

The manufacturing system engineering process

Today's MSE process is still poorly formalized and requires significant effort and time for the engineer to deal with it. Furthermore the different tasks linked to MSE are missing a comprehensive, integrated information system ...