# Modelling conceptual design based on artificial intelligence - Application to mechatronic design (Moulianitis, 2003)

**Abstract:**

Ιt was only by the middle of the 20th century when design – an intense human activity – became the focus point of scientists towards the direction of its formalization and “scientification”. Since then, design philosophies, models, methods and techniques have been developed. The systematic formulation of design is very difficult since it is a perceptive process with special characteristics for every person or team. The theoretical foundation of design is more difficult and until now there have been made relatively few attempts for developing a generalized theory of systematic design. This theory is still in pre-scientific phase, while there is rich knowledge on design methodologies in specific applications. In this thesis, a mathematical model towards systemizing the conceptual design phase is introduced. A mathematical interpretation of the general concept generation and evaluation processes is analyzed. The design entities and rules governing a design problem are represented using fuzzy, Boolean and many-valued logic depending on how well-defined is the knowledge of the field that the model is applied to. A mechanism for the automatic generation of the degrees of satisfaction of the design specifications by the feasible solutions subjected to the design constraints is also proposed. From a matrix that contains these degrees, the set of all possible combined solutions is generated. The generation of the set of final solutions, that is a subset of the set of the combined solutions, is based on a suitable partition of the Euclidean space. In order to avoid the combinatorial explosion that occurs during design space search, two heuristic search methods have been developed based on vector analysis. A frame for introducing design indices for the evaluation of alternative solutions is also proposed. The formulation of the design indices is based on fuzzy logic and more specific on T-norms and averaging operators. The guidelines for the selection of the class of operators and then for the operator itself are also given. Using this frame, the designer can form evaluation indices based on special characteristics that the product must inherit. Furthermore, the “Mechatronics Index” is introduced. Using this index, the designer can select the most intelligent and flexible alternative solutions that have the minimum complexity. The formulation of the index is based on these three common characteristics of the mechatronics products. Finally, the knowledge for the design of grippers for handling non-rigid materials is acquired from experts and literature and organized in a knowledge-based system. This system is the first to appear in the international literature for the conceptual design of grippers for handling non-rigid materials. In this system the above methods for the concept generation and evaluation has been tested and studied. The present thesis proposes a methodology that of it can be used for the realization of the conceptual mechatronics design or for the development of new intelligent knowledge-based systems for the conceptual mechatronics design of products.

**Link:** http://openarchives.ekt.gr/visit/87867