Virtual Function Generators: Representing and
Reusing Underlying Design Concepts in Conceptual
Synthesis of Mechanisms for Function Generation

Younghyun Han1, and Kunwoo Lee2

1 Institute of Advanced Machinery and Design, Seoul National University,
2 School of Mechanical & Aerospace Engineering, Seoul National University,
San 56-1, Shinlim, Kwanak, Seoul 15 1-742, Korea
{yhhan, kunwoo}@cad.snu.ac.kr



Abstract. This paper describes an approach to represent and reuse efficiently
the underlying design concepts in the existing mechanisms in order to synthesize 
mechanisms for function-generation and motion-transmission. A notion of
virtual function generator is introduced to conceptualize and represent all possible 
underlying design concepts in the existing mechanisms. The virtual function 
generators are extracted from the existing mechanisms and composed of
one or more primitive mechanisms together with the involved functions. They
serve as new conceptual building blocks in the conceptual synthesis of design
alternatives. The whole design concept or sub-concepts of the mechanisms can
be represented and reused efficiently by the notion of virtual function generator.
New mechanisms are generated by extracting and combining the underlying
design concepts via the virtual function generators. The capability of the proposed 
approach is illustrated with a design example.
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