Current Situation and Problems for Representation of Tolerance and Surface Texture in 3D CAD Model

Abstract

This paper explores current problems in representing of tolerances and surface textures in 3D computeraided design (CAD) models. Today, all available 3D product data, such as dimensioning and tolerance, are not used in digital form throughout the product development processes. Tolerance and surface texture data for product are very important in design data. In downstream processes, such as process planning and manufacturing, such data are referenced to determine machining processes and process parameters. In inspection, such data provide criteria for verifying functionality of the machined product based on measurement results. Previously, such data were communicated using 2D drawing and not included in 3D CAD data.3D models are widely used and demand is increasing for the annotations in 3D model, e.g., standard for the digital product definition data practices was developed by ISO, and the guidelines for 3D drawing were developed by the automobile industry. This paper explores needs and requirements of tolerance and surface texture representations which are associated with 3D CAD data in product development processes, together with current status, problems, and future works in representing tolerances and surface textures associated with 3D CAD data.