Variant design for mechanical parts based on extensible logic theory

A new variant design method of mechanical part is proposed based on extensible logic theory, to support design knowledge reuse more efficiently in computer aided conceptual design. In this method, matter-element, event-element and relation-element are used to characterize the feature information, connection constraint relations and topology variant operations of mechanical conceptual structures respectively. Extensible composite-element model of product part is established sequentially based on the above three basic-element models (matter-element, event-element and relation-element). Moreover, five types of variant operations are defined in order to realize structure variations and shape design of mechanical parts. Finally, an example of shaft housing part in grinder component is taken to explain the part variant design process in details, in which the efficiency and effectiveness of this method are illustrated simultaneously.