Methodological Integration of Parametric Associative CAD Systems in Product Lifecycle Management (PLM) Environment

The automotive engineering process is characterized by a long and complex design process which starts with the first sketches in the preliminary design phase and extends to the final detailed CAD and physical models. Every design phase includes different process steps which are interconnected with each other. For a better handling of all created information in the different design stages there is a demand for capable Product Lifecycle Management systems (PLM). Furthermore, one of the important parts of PLM systems is the integration of the virtual product development process which can be based on parametric associative (PA) computer-aided design (CAD) systems. The main challenge is the full integration of all created PA CAD data with these kinds of system. To achieve the full potential of PA CAD systems, especially in view of the complexity of the CAD parts and assemblies, it is important to have a clear understanding of how best to use such systems. Accoring to Shah and Ma¨ntyla¨ [1] parametric systems solve constraints by applying sequentially assignment to model variables, where each assigned value is computed as a function of the previously assigned values. Related to design process associativity is the fix relationship and connection between geometrical entities and objects. These associative relationships include also the connection of 3D models and down stream process related elements. The focus of this paper is to present the results of a descriptive study which has been accomplished to identify the challenges, problems and weaknesses involved in the use of PA CAD systems in the automotive design process. After a short introduction the result of a literature survey is presented. The review is followed by presentation of the results of a questionnaire and interview study of engineers working in the automotive industry. This study demonstrates that engineers have significant difficulty in identifying and structuring the parameters and associative relationships used in PA CAD, especially in distributed design tasks. The review and the empirical study demonstrate the necessity of a generic integrated approach working with PA CAD systems. The results of this descriptive study will be used to support the methodological integration of the created CAD components in PLM environments.