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Time to market

Time to market

Figure.B: Time to market without and with CA Systems

1.2    CAD - Computer Aided Design

A Computer support during the design of the product is utilising of the computing machinę during the product design process. The Computer design support is called the Computer Aided Design (CAD). The CAD system is a Computer system based on the mathematical product description and application analyses.

The Computer aided design is the intcractivc modclling of physical Systems on computers, allowing various analysis of the design variants. The aim is to prepare the model of the product to be suitable for manufacturing. The CAD Systems are not in the first place charactcristic by design description. The significant mark of the CAD systems is modelling and simulation and it is the significant difference considering a Computer graphics. Simulation according the Computer science lexicon is a specific kind of modeling of systems. Simulation has a great meaning, it is not necessary after drafting stage to make a prototype and then to verify it. Verification and inspection are done parallel with the other design activities.

The principle - at first to model, to simulate and to verify and at last to manufacture - appears as a very good economical fundamental.

The modem CAD system does not look like as the first Computer system dedicated to 2D drafting. The present systems enable modelling according the 3D primitives. The product is not drawn but it is modelled and virtual completed.

1.3    Background of CAD development

Before 1960 the Computer application for design does not exist. Between 1960 and 1970 the most Computer programs in cngincering were limited to calculation programs which were processcd in batch. Thus, there was no interaction possible between the user and the program. In the seventies the first mainly academic CAD systems aim an interactively supporting design as a 2D sketching.

After 1970, the mcaningful step was development of graphical terminals that make possible to work interactively. However, the available hardware was very expensive and therefore the using was restricted to a limited numberof companies and people. Accordingly the CAD applications occurred in smali amount.

From 1980, rapid developments of Computer eąuipment lead to morę powerful computers hardware and Computer systems. Workstations and pcrsonal computers becamc widely available at rcasonable priccs. This development enabled the introduction of CAD on a wider scalę. Knowledge based engineering system for design was introduce in the mid-eighties. These systems employ artificial intelligence tcchnology for representing expert design and manufacturing knowledge. The advantage of these systems is that similar designs with different specifications and geometry can be generated much faster. However, the realisation of truły intelligent CAD systems still is an academic research issue.