Shape optimisation using evolutionary techniques in product design
Introduction
The competition in the current global markets is commanding rapid improvements in product performance and quality with the reductions in costs and development time-scales. This forces the product-oriented manufacturing enterprises to seek more advance technologies to gain profits by reducing the design development time. As a result, design automation is required to improve the functionality of the designs and reduce the development time and thus reduce the cost, especially when designing complex surfaces are required. Designing the shapes of products is the primary activity of the design process and the CAD/CAM systems used today for the designs provide limited facilities for automatic optimisation of surfaces. They supported an iterative surface optimisation, which is very time consuming and requires an enormous amount of skilled engineering labor.
On the other hand, evolutionary computation techniques have been successfully applied to engineering design optimisation, constraint satisfaction, symbolic equation solving and manufacturing process planning. These adaptive and generative techniques provide more creative and intelligent support to designers than other design support systems that have to rely on geometric representations and explicit deductive inference mechanisms. However, the application of evolutionary computation techniques, such as genetic algorithms (GAs) (Davis, 1991, Goldberg, 1989, Holland, 1975), in product design has been limited (Gen and Cheng, 1997, Hawkes and Abinett, 1984). The difficulty arises from the fact that product design requires a wide variety of knowledge and information at the early creative state of the design process that is difficult to formulate in a computer system (Karl, 1997, Medland, 1986, Roy et al., 1999). One of the important issues in applying evolutionary techniques to conceptual design is how to represent 3D structures in a way in which genetic algorithms can be used to support the process of generating and optimising innovative and imaginative geometric components and parts (Frazer, 1995, Graham, 1995). So this paper examines two stages of using genetic algorithms in design-how to encode designs as chromosome and how to translate certain manufacturing constraints into the evaluation functions which can be manipulated by GAs.
In this paper, an improved simple GA is used to demonstrate the concept that surface optimisation can be effectively supported within an existing CAD system. Work in this paper focuses on the most difficult aspect of design representation, the geometry or shape of design, based on the ergonomic and aesthetic consideration, and factors such as materials and costs are not considered at this stage. Based on the discussion and analysis of the existing shape representation methods, how to choose optimal characteristic parameters for shape design and how to define the combination of the geometry or shapes from simple to complex are presented in this paper. The methods presented in this paper have been tested in the early case studies on the simple ruled and non-ruled surface optimisation problems. The analysis of the initial research results and the discussion of the future work are also presented in this paper.
Section snippets
Shape representation and optimisation
Existing solid modeling systems provide facilities for creating, modifying and inspecting models of 3D solid objects, but there are a large number of different possible methods for representing such models in a computer. However, representation schemes may be divided into six general classes (Rooney & Steadman, 1997): Pure primitive instancing; Generalised sweeps; Spatial occupancy enumeration; Cellular decomposition; Constructive solid geometry (CSG) and Boundary representation. Among them,
Application development
The proposed project in this paper aims to investigate how genetic algorithms can be successfully applied in product design and to develop an evolutionary design system capable of evolving solid object designs which are easy to manufacture and can satisfy all the given constraints. When applying a genetic algorithm to any applications, four main elements must be considered (Bentley, 1999): Firstly, the phenotype must be specified, in other words the allowable solutions to the problem must be
Conclusions and future work
The paper is about the early stage work of the research project – the application of evolutionary computation techniques in design for manufacturability. This research is concerned with the development of a generic computer framework in which genetic algorithms are used to support the process of automatically generating the geometric forms of products using primitive shells that are easy to manufacture (Sun, Frazer, & Tang, 1999). The surface optimisation within a CAD/CAM system is founded to
Acknowledgements
This research project is supported by a UGC Ph.D. project grant from the Hong Kong Polytechnic University. The authors would like to acknowledge the support from academic and research staff in the Design Technology Research Centre of School of Design.
References (19)
- Bentley, J. P. ( 1996). Generic evolutionary design of solid objects using a genetic algorithm. Ph.D....
Handbook of genetic algorithms
(1991)- Frazer, J. (1995). An evolutionary architecture, Architecture Association,...
- Frazer, J., Tang, M. X., & Sun, J. (1999). Towards a generative system for intelligent design support. In Proceedings...
- et al.
Genetic algorithms and engineering design
(1997) Genetic algorithms in search, optimization, and machine learning
(1989)- Graham, P. (1995). The application of evolutionary and rule-based techniques in computer aided design. Ph.D....
- et al.
The engineering design process
(1984)
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