A primary “must” of axiomatic design theory is the first axiom, stating that independence of functional requirements should be maintained throughout the design process. Para-complete logics, such as Fuzzy logic, give us a powerful instrument to express “mathematical/functional” interaction between FRs and DPs, especially when this interaction cannot be expressed by a precise “mathematical function (i.e. the case in which we want to express several data from VOC (Voice of Customer) investigation, building an FR for a defined design performance), and so can be codified only using “Linguistic variables”. Para-complete logics, among which the Fuzzy logic is, for us, the most powerful, violate the principle of the excluded third party, so that the effects of DPs’ changes on the same FR can be considered partially independent each other. Recent paper investigated changes in Decoupled Design’s concept when para-complete logics are applied in FRs-DPs link definition and evaluated, using an example, the impact of decoupling capability of designer using composition rules on FRs, in order to make the design matrix diagonal or lower triangular by decoupling effects of several DPs on different FRs using Fuzzy formulation. In this paper that kind of approach is extended to optimization method; in this paper we want demonstrate how is possible, using Fuzzy formulation and respecting the first Suh’s Axiom, to elaborate a simple optimization routine based on variation and bounding of DPs values in given ranges. Using that method, Defuzzyfication of DPs for Design optimization will became very simple. A new practical application will be explained.
AXIOMATIC FRAMEWORK APPLIED TO INDUSTRIAL DESIGN PROBLEM FORMULATED BY PARA-COMPLETE LOGICS APPROACH: THE POWER OF DECOUPLING ON OPTIMIZATION-PROBLEM SOLVING
NADDEO, ALESSANDRO
2006-01-01
Abstract
A primary “must” of axiomatic design theory is the first axiom, stating that independence of functional requirements should be maintained throughout the design process. Para-complete logics, such as Fuzzy logic, give us a powerful instrument to express “mathematical/functional” interaction between FRs and DPs, especially when this interaction cannot be expressed by a precise “mathematical function (i.e. the case in which we want to express several data from VOC (Voice of Customer) investigation, building an FR for a defined design performance), and so can be codified only using “Linguistic variables”. Para-complete logics, among which the Fuzzy logic is, for us, the most powerful, violate the principle of the excluded third party, so that the effects of DPs’ changes on the same FR can be considered partially independent each other. Recent paper investigated changes in Decoupled Design’s concept when para-complete logics are applied in FRs-DPs link definition and evaluated, using an example, the impact of decoupling capability of designer using composition rules on FRs, in order to make the design matrix diagonal or lower triangular by decoupling effects of several DPs on different FRs using Fuzzy formulation. In this paper that kind of approach is extended to optimization method; in this paper we want demonstrate how is possible, using Fuzzy formulation and respecting the first Suh’s Axiom, to elaborate a simple optimization routine based on variation and bounding of DPs values in given ranges. Using that method, Defuzzyfication of DPs for Design optimization will became very simple. A new practical application will be explained.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
