Shape and position tolerances contain a combination of functional and visual aspects of a product. They affect functionality as well as its optical impressions. If tolerances are chosen too generous the production costs are low but the number of subsequent machining increases. Are they chosen to tight the functionality can be guaranteed but the costs for their achievement will grow dramatically. Further the variation of shape resulting from the shape and position tolerances causes – added up in assemblies – variation of the position. State of the art tolerance simulation software provides many kinds of simulation methods. Usually, they re-port the results only in tabular contributor reports, process capability indices and distribution curves. A visualization of the results for example in Virtual Reality (VR) is not supported.
VR is a very effective and useful tool for visualizing geometry in all stages of product creation. Particularly in the product design stage there are many possibilities for an extensive us-age of immersive stereo projection units. Normally no additional information besides geometry is displayed, which means only the geometry of a part, or an assembly is displayed, and no information is included e. g. about tolerances, shape variation and their effects.
This thesis focuses on the development of a method to visualize possible shape variation caused by shape and position tolerances as additional information besides the nominal geometry. Starting with a complete geometrical model and its associated tolerance specification a 3-step-procedure-model guides through the model preparation, the simulation of possible shape variation and last the generation of a visualization scene that can be shown in low-budged 3D-viewers as well as in high-end stereoscopic VR units. Several geometrical and color-coding methods are developed which enable to identify very small details of the shape variation in spite of lower screen resolutions.
Only with a full integration of newly developed methods in the software environment of the product development process and also their integration in the whole product creation process it is possible to shorten process sequences and increase their robustness. Therefore, a Process Data Management System (PDM System) is used as a data backbone to handle all kind of data during the visualization of shape variation as well as the entire workflow of the tolerance review. Furthermore, the PDM System is used to connect all necessary and involved divisions that can contribute and need relevant information. The requirements for this holistic integration and the needed modifications of the PDM System are also shown in this thesis.
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