【文章內(nèi)容簡介】 represented using a set of functional features, while the rest of the geometry is abstracted as a set of linkages. Part functionality is correlated with the sketching abstraction using data structures called functionform matrices. Although the work was pioneering and promising in the application domain of sheet metal manufacturing, its usefulness is limited in providing conceptual design support for stamping metal part but not die structure. In the past few years, functional modeling approach has also proven to be suitable for tooling design such as injection mould design [17, 18], though the application is still in its infancy stage. However, no literature exists so far applying functional modeling technique in die structure design. Hence in this paper we hope to utilize the advantages of functional modeling approach to provide conceptual support for die structure design, with which, various functional reasoning techniques should be integrated to develop a prehensive functional structure of die design object. 3. A COMPREHENSIVE FUNCTIONAL MODELING FRAMEWORK . Functional relationships In functional modeling, various functional relationships between functions and structures should be elaborated in order to develop a prehensive functional model. Three critical types of relations, ., deposed into, realized by, and supported by relations are defined in this paper. Deposed into relation: This relation indicates a function is deposed into simple subfunctions. Referring to figure 1, a main function F1: Perform the stamping operation is deposed into simple subfunctions F11: Form the stamping part, F12: Strip the stamping part, and F13: Eject the stamping part. Realized by relation: This relation indicates a function is realized by a physical structure through a mapping between them. Referring to figure 1, the function F11: Form the stamping part is realized by a physical structure S11: Punches. Supported by relation: This relation depicts the dependency of one function (or structure) on other functions that provide supporting roles. In other words, if needed supportive functions are not provided, their supported function (or structure) may not be fully actualized. Referring to figure 1, the function F11: Form the stamping part that directly influences the immediate achievement of the purpose is supported by a supportive function F111: Support the stamping part that is not responsible for the immediate achievement of the purpose but affects soundness of achievement of the purpose. In other words, the function F11 may only be fully actualized due to the presence of the supportive function F111. Similarly, the structure S11: Punches may only be fully actualized due to the presence of another supportive function F112: Guide the punches. Incorporation of supportive function was borrowed from Multilevel Flow Modeling (MFM) based reasoning approach [19] from different views of modeling space, though in a more generic, lower level functional context, facilitates generation of a prehensive functional model. . A functional modeling framework with various functional reasoning paths Figure 2 shows the features of the proposed functional modeling framework that consists of two layers, namely function layer and structure layer. The function layer defines some functions necessary to pose other functions, or support other functions (or structures). The structure layer describes the underlying physical embodiments of the functions. In this functional modeling framework, if a desired function (or physical structure) may only be actualized when other functions are present, the latter should first be synthesized as supportive functions to generate a more plete functional design. On the other hand, a desired function is not deposed into subfunctions, unless a matching physical structure can not be found to realize the desired function. The proposed approach can prevent the domain problem being deposed “too fine”, causing binatorial explosion. Generally, a desired function (overall functional requirement, subfunction or supportive function) or a physical structure can be acplished in the following generalized functional reasoning path types: ?Functional reasoning path type I: a desired function is realized by a physica