Bridging the knowledge gap between design, manufacture and measurement in the field of surface texture

Surface texture, a core part of geometrical product specifications and verification (GPS), is embraced by the whole surface manufacture chain from design through manufacture and measurement, and plays a significant role in determining the functional performance of workpieces. The delivery and implementation of surface texture knowledge in GPS, however, is undergoing critical problems in current practice. Surface specification/design systems lag far behind the measurement systems. This is caused by knowledge gaps between design, manufacture and measurement systems exemplifying the necessity of an infrastructure which synergy seamlessly between different stages.

This thesis documents the development of a surface texture platform called CatSurf to bridge the knowledge gaps. A category theory based knowledge modelling methodology is proposed to underpin the mathematical foundation of the CatSurf. Deploying this methodology, the knowledge modelling for areal and profile surface texture is carried out. The design and implementation of the CatSurf system is developed based on modelling. In addition, the CatSurf system is integrated with Computer Aided Design systems by utilising a Component Object Model (COM) and XML (Extensible Markup Language) based integration methodology.

The integrated CatSurf system provides unambiguous surface texture information for designers and metrologists, and enables metrology assisted design and manufacture to become reality. Currently, it is an executable system with three different modules which can be integrated with CAD systems such as AutoCAD and SolidWorks. A special module is developed for Rolls Royce with a single roughness parameter Ra for gas washed surfaces. The system is tested and recognised by various parties such as Rolls Royce, CAx and GPS experts, computing and mechanical engineers and researchers, etc.