This book contains a selection of revised versions of papers presented at the Third Eurographics Workshop on Intelligent CAD Systems, which was held at Hotel Opduin on the island of Texel in The Netherlands, April 3-7, 1989. The workshop theme was Practical Experience and Evaluation. It included five paper presentation sessions, each followed by a discussion. The workshop closed with a general discussion. The book is therefore divided into five parts: design process, system architecture, languages, geometric reasoning, and user interface. A report on the discussion session, written by the session's moderator, concludes each part. These reports are not intended to be exact records of the discussion, but rather the moderators' summary of their contents. The aim of the workshop was to share the experience the participants gained by developing intelligent CAD (Computer Aided Design) systems, and to evaluate the developed systems to determine which features were still lacking. The workshop was organized as the last one in a series of three workshops under the same title. The first workshop focused on theoretical and methodological aspects, resulting in a sound theoretical basis for intelligent CAD systems. Implementational issues were discussed at the second workshop, paying attention to systems developed with reference to this basis. The experience and evaluation showed a dual outcome. Firstly, it resulted in the development of a new generation of intelligent CAD systems. Secondly, it led us to the development of new theories for intelligent CAD.

CAD (Computer Aided Design) technology is now crucial for every division of modern industry, from a viewpoint of higher productivity and better products. As technologies advance, the amount of information and knowledge that engineers have to deal with is constantly increasing. This results in seeking more advanced computer technology to achieve higher functionalities, flexibility, and efficient performance of the CAD systems. Knowledge engineering, or more broadly artificial intelligence, is considered a primary candidate technology to build a new generation of CAD systems. Since design is a very intellectual human activity, this approach seems to make sense. The ideas of intelligent CAD systems (ICAD) are now increasingly discussed everywhere. We can observe many conferences and workshops reporting a number of research efforts on this particular subject. Researchers are coming from computer science, artificial intelligence, mechanical engineering, electronic engineering, civil engineering, architectural science, control engineering, etc. But, still we cannot see the direction of this concept, or at least, there is no widely accepted concept of ICAD. What can designers expect from these future generation CAD systems? In which direction must developers proceed? The situation is somewhat confusing.

CAD (Computer Aided Design) technology is now crucial for every division of modern industry, from a viewpoint of higher productivity and better products. As technologies advance, the amount of information and knowledge that engineers have to deal with is constantly increasing. This results in seeking more advanced computer technology to achieve higher functionalities, flexibility, and efficient performance of the CAD systems. Knowledge engineering, or more broadly artificial intelligence, is considered a primary candidate technology to build a new generation of CAD systems. Since design is a very intellectual human activity, this approach seems to make sense. The ideas of intelligent CAD systems (ICAD) are now increasingly discussed everywhere. We can observe many conferences and workshops reporting a number of research efforts on this particular subject. Researchers are coming from computer science, artificial intelligence, mechanical engineering, electronic engineering, civil engineering, architectural science, control engineering, etc. But, still we cannot see the direction of this concept, or at least, there is no widely accepted concept of ICAD. What can designers expect from these future generation CAD systems? In which direction must developers proceed? The situation is somewhat confusing.

Records of the 2nd Eurographics Workshop on "Intelligent CAD Systems", Held on April 19-23, 1988, at Konigshof Congress Centre, Veldhoven, the Netherlands

Computers have been employed for some time in engineering design mainly as numerical or graphical tools to assist analysis and draughting. The advent of the technology of artificial intelligence and expert systems has enabled computers to be applied to less deterministic design tasks which require symbolic manipulation and reasoning, instead of only routine number processing. This book presents recent examples of such applications, focusing on mechanical and manufacturing design. The term 'design' is interpreted here in its wider sense to include creative activities such as planning. The book covers a wide spectrum of design operations ranging from component and product design through to process, tooling and systems design. Its aim is to expose researchers, engineers and engineering designers to several developments in the emerging field of intelligent CAD and to alert them of the possibilites and opportunities in this exciting field.

Current CAD (Computer-Aided Design) systems, as used in many industries, are able to manipulate geometrical shapes very successfully. However, some would say that CAD means Computer-Aided Drawing'', i.e. CAD is only a very sophisticated drawing board, never intended to assist the thought processes of the designer. Automated design systems do exist, but these are limited to specific products with only a few varying parameters. This book deals with Intelligent CAD'', the concept of a system that could assist designers throughout the design process, deal with any object, and be connected to any other information processing system, such as CAM. The research papers collected here are from designers, and from researchers in Artificial Intelligence and Computer Science.

The importance of CAD to electronics technology Computer-aided design (CAD) is one way of coping with the problem of how to design and build very complex systems. This problem is particularly acute in electronics technology. Designs are now (1984) said to be design-limited, rather than technology-limited. It can take months to generate a design for a chip, so that it might be obsolete before it can be manufactured. Manual design of large-scale integration (LSI) chips (circa 10,000 gates) is almost impossible. However, using current technology it is possible to produce chips having 250,000 gates. It is understandable, therefore, that there is great interest in improving existing CAD systems. Designers of CAD systems are concerned with formalizing and automating as much of the design task as possible. Automating design of any kind has long been acknowledged as a project fraught with intractable problems. A human designer has to have an understanding of the nature of the materials used in manufacture, a knowledge of common problems and well-tried solutions, and above all, creativity in producing new designs. Understanding, knowledge and creativity are three properties even the most artificially intelligent of computer programs have been entirely lacking in until very recently. Some people would deny computers these qualities entirely, on philosophical grounds (eg Dreyfus 1979; Searle 1981). There are few theories in cognitive psychology which can help.