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This paper presents results of transdisciplinary research on the development of a bioinspired computational framework for engineering design. This framework is intended to support design by addressing three critical design objectives, including novelty, optimality, and robustness. It provides several computational models and methods, which are inspired by fundamental processes occurring in nature, and discusses their potential for enhancing design. They include models and methods for evolutionary, developmental, and coevolutionary design. Their use is illustrated with examples from the area of steel structural design ranging from a simple cantilever beam design problem to a much more complex problem of designing wind bracings in tall buildings. The paper also shows how several methods and models can be integrated and form a coherent bioinspired computational framework for engineering design. [ABSTRACT FROM AUTHOR]

Tolerance is almost ubiquitous during the whole product life. However how to effectively embody and interpret the semantics of tolerance in three-dimensional computer-aided design systems is still an open issue. Variational geometry is recognized as one of the most promising solution for it. And the methods for systematically and efficiently generating the variational geometries of all kinds of geometric entities with tolerances are imperative. In this paper, a degree-of-freedom (DOF)-based approach is proposed for generating variational geometry of a hole with composite tolerances imposed on its centerline and surface at the same time. All possible combinations of tolerance requirements for a hole are discussed. And the mathematical models for variational geometries of the centerline and the surface of a hole are deduced. Furthermore two strategies for improving the efficiency of generating the variational geometry of a hole are presented. Finally, the algorithm is implemented and some test results are given. Note to Practitioners—This paper is motivated by the problem that the tolerance information in the current computer-aided-design CAD systems lacks the necessary engineering semantics, which causes tolerance information that cannot be correctly used and impedes the integration of CAD and computer-aided manufacturing (CAM). Existing approaches have partially solved the problem for the pattern of holes (POH) and plane feature based on variational geometry. But the computational efficiency with the variational geometry method is very insufferable due to a lot of Boolean intersection operation. In this paper, the hole feature is mainly considered because its tolerance specification is quite different from other features and is imposed on the centerline and the surface of a hole at the same time. First, the mathematical model is given for interpreting the engineering semantics of the tolerance of the centerline and the surface based on the variational geometry, respectively. Then, the tolerance principles are further considered for compensation between the above two types of tolerance. More important, a direct method, which can largely avoid the Boolean intersection operation, is proposed for generating the variational geometry. The computational efficiency is thus improved dramatically and the variational geometry is generated almost in real time. This enables virtual assembly and virtual inspection with the tolerance information to be possible. [ABSTRACT FROM AUTHOR]

the paper presents some new concepts applied in Computer Aided Design regarding some hardware solutions, possibilities to optimize the organization of an design office and a case study of the concurrent engineering and project management used in the design process. [ABSTRACT FROM AUTHOR]

Design is the foremost step in the development of any electro-mechanical product. One limitation of existing design tools is that they only focus either on the initial design phase such as customer needs gathering, or on the later phases such as design embodiment or detailed design phase. As a result, there are very few existing computational tools to aid the designers at the conceptual design stage. The proposed research seeks to eliminate this drawback by providing a computerised conceptual design framework that incorporates Modularity, design for assembly (DFA) and design for variety (DFV) principles. Conceptual design alternatives obtained from the proposed research framework are ranked based on minimum assembly time, and are composed of modules in such a way that future changes in customer needs are satisfied only by replacing certain modules. This paper provides a detailed discussion of the proposed framework obtained by amalgamating Modularity, DFA, and DFV. Working of the framework is also demonstrated with the help of an electronic toothbrush design example. [ABSTRACT FROM AUTHOR]

The C–K theory is a recent theory of reasoning in design. Despite many practical applications, the theory has not yet been operationalized in the form of a computational design tool. In this paper, we argue that, in order to build such tools, a third space—an environment space E—must be introduced to the theory. Therefore, we extend the C–K design theory, using ideas and principles from situated cognition. As we discuss, the new version provides a theoretical background for building personal design assistants—creative and adaptive design tools. [ABSTRACT FROM AUTHOR]

Abstract: This short paper presents 10 challenging research areas in the general field of computer-aided design. The research problems come from the author''s personal experience, and as such are highly subjective. All findings and opinions are those of the author and do not represent any of the institutions the author is affiliated with. [Copyright &y& Elsevier]

Engineering design focuses on the development of products and artefacts to satisfy the specified function. Although considerable advances have been made over the last two decades in functional modelling, there is not very much progress on commercial Computer-Aided Design (CAD) systems that really aid the designer in converting functional specifications to concept variants. Based on our previous work on Behaviour-driven Function-Environment-Structure (B-FES) modelling framework, this paper presents a functional design software system, called "FuncDesigner", to support the functional design of mechanical products through functional reasoning steps, including causal behavioural reasoning and functional decomposition. A function object library and a behaviour object library have been developed as well to serve as the knowledge base for the computerised functional modelling environment. The proposed functional design software system has been evaluated with a design example of a terminal insertion unit in an automatic assembly system for manufacturing electronic connectors. [ABSTRACT FROM AUTHOR]

The re-use of previous design knowledge is a potentially important way to improve design efficiency. To do so, both the product under study (product data) and the argumentation leading to it (process data) must be stored throughout the engineering design process. CAD systems do the former very well; the latter has to be developed. The objective of the paper is to contribute to a system able to capture design process rationale and make it available for re-use in the current design project or in further projects. The approach involves extracting elements of argumentation and maintaining connections between arguments, proposed solutions and decision-making contexts. Criteria exchanged between design participants leading to the acceptance or refusal of solutions are key clues to understanding design rationale. A descriptive model of a design process is proposed, based on features capitalising on the rationale of design: a conjecture (an element of a solution proposed for validation), a criterion (an element of evaluation of the proposal) and the interactions between them. Conjectures capture alternatives; criteria provide access to the rationale behind the alternatives. The model was validated by laboratory-based experimentation. A computer-aided tool supporting and analysing criteria–conjecture interactions was developed, focusing on the context of decision-making and currently available information. It comprises a database storing the interactions and five modules to process the data for use in a design context. The raw data in the database are abstracted into knowledge according to the manner in which a design engineer wants to retrieve and use it. This structure is represented in the form of a data-processing prototype. [ABSTRACT FROM AUTHOR]