Computer-assisted structural design of industrial woven fabrics.

摘要

This thesis describes the concepts and development of an overall computational framework for aiding the engineering design of woven industrial fabrics. The process of fabric design for performance is based on a combination of heuristic principles and well-established, quantifiable structure/property relationships. To do so with the help of a computer necessitates an ability to represent and cohesively combine several types of knowledge. Since the design specifications for an industrial fabric are specified in terms of some (out of a set) of quantifiable target properties, independent of end-use, it is possible to develop a generalized CAD system for this domain.; The important aspects of a CAD "environment" intended for the design of any general hierarchically structured object/assembly are described, together with previous research investigations into the understanding and formalization of these salient system features. The fabric design principles and heuristics representing the encoded knowledge of a domain expert are embedded in a rule-based programming scheme, which is closely integrated with quantifiable structure-property relationships in the form of conventional algorithmic procedures.; A functional model of this hybrid CAD system is formulated, along with the necessary organizational steps to have the software components of the system work together in a seamless and logical fashion. An important factor in designing the system architecture is to allow the greatest flexibility in interaction of the software sub-systems so as to permit some general applicability to other types of fabrics and textile structures. Much attention is devoted to explaining the two-stage model of the design process, and a typical design case is traced through a design session.; The CAD system, in its ultimate form, proposes to include a detailed analytical component/module to simulate additional important fabric properties. At this stage, this module comprises a computational mechanistic model for the planar uniaxial/biaxial load-deformation characteristics of a plain woven fabric. The theoretical development and experimental validation of this biaxial model is treated herein. (Abstract shortened with permission of author.)