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| Introduction:
The competition level of a company is an indication for the success of that company in the market. To maintain and even to improve that competition level a lot of attention is given to time-to-market, cost prize of the product, lifecycle costs and quality. It is generally known that new working methods based upon co-operation between the business functions and the business disciplines, are contributing to better results on these points. Compare this to a situation, known by everyone: The time is not so far away that it was experienced brilliant to fit a bad designed product after all to its function. Mostly that was not communicated to the design department. This is a classic sample of non-communication leading to cost increases, loss of productivity and decreasing of quality. The new working methods for which, thanks to structural co-operation, optimal use is made of existing knowledge, are exceeding the boundaries of companies. Because, increasingly often companies are rerouting the activities towards their core business and more and more of the activities are transferred to partners (co-designership and co-makership). An important new trend connected to this, is the fact that partners have a larger influence on the development a the product. Principals provide functional specifications: by doing so less time and money is spent than before in the process of detailing technical specifications. By this, also a certain part of the risks of development is avoided. Preferable, use is made of the expertise of the partner. This partner, provided that his focussed op new chances and challenges, "grabs" this opportunity to increase his added value. The partner is also becoming more and more a system- than a component supplier. However, the number of companies involved with development and production remains the same, the number of subcontractors with direct relations to end producers, is decreasing strongly. A network is build up between companies related to the product development and product realization. For the end assembler the distance to the majority of aforementioned companies is increased. Such a network can only function by means of high graded information supplies. This information supply is only thinkable if modern information technology is used. Paper flows contains large risks concerning the monitoring of versions and the informing of people at the appropriate time about new versions of documents. Cals: The total of new working methods, modern information technology and agreements about the standards to be used, is internationally known as the CALS-strategy. CALS (Continuous Acquisition and Life-cycle Support), is monitoring the complete lifecycle of a product, from offering-stage up to and including the usage phase and the "putting-out-of-order" stage. CALS relates to a certain method of handling information. Right now use is made of document based information supply based upon paper and neutral transfer formats (such as IGES en DXF for technical drawings). Model-based information supply Within the CALS-strategy model based information supply is centralized. Examples are product models as defined within STEP, ILS-databases (ILS: Integrated Logistic Support) for logistic support and the virtual document. The central idea behind model based information supply is that data should be stored on a place where it is accessible by everyone (this does not mean in physically one place) and have linked relations. Take an encyclopedia as an example. Say: data-elements are renewed, such as a small part of video, only that small part of video has to be replaced, and all the existing relations take care that the renewed information-element is accessible is. The result of this is that everybody based upon adhered authorization can access, change or add information. Information supply on demand. Model based information supply is offering the necessary possibilities for good version management, authorization management and re-use of information. Looking closely to technical documents, within the CALS-strategy clear agreements are made about how information should be available. Put into a line, these agreements look like the following. Technical drawings IGES (Initial Graphics Exchange Specification)
VDA-FS (VDA-Surfaces Interfaces)
SET (Standard d'Echange et de Transfert)
STEP (STandard for the Exchange of Product model data)
Text and Fig’s
Interactive Electronic Technical Manuals (IETHS)
Graphical information
A complete survey of all the CALS-standards and the qualifications related to usage is given in the CALS Handbook issued by the PDICALS Center at the end of 1995. Pragmatical approach: The software-industry stands never in front to implement new standards. It is, in a restricted vision, also commercially not interesting to make agreements about data structures. Because, this would make it "too easy" for the user to switch over to a product of the competitor. Some pragmatics is therefor required. Joining the "de facto" standards or using products that are dominating the market, is often a wise decision. The format is, assuming that it has sufficient functionality, at itself not important. The information must be accessible. Anticipating on the support by applications of the CALS-formats, good agreements must be made about the data formats. In a Windows-environment agreements could be based upon:
The agreements are important. They must be well specified and there should be, certainly in the startup phase of working by these agreements, a firm check on usage. The daily practice is showing that companies often are embracing an agreement, without the certainty that they fulfill the requirements of that agreement. The PDI/CALS Center works very much in co-operation with the Dutch Industry. Considering the gathered experiences the following two recommendations can be given:
Terms and abbreviations:
For the exchange of (geometric) data between CAD/CAM-systems the following standards are available:
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