CAD-Based Tolerance Analysis in Preliminary Design Stages Enabling Early Tolerance Evaluation

Associated with manufacturing and assembly processes, inevitable geometric deviations have a decisive influence on the function and quality of products. Therefore, their consideration and management are important tasks in product development. Moreover, to meet the demand for short development times, the front-loading of design processes is indispensable. This requires early tolerance analyses evaluating the effect of deviations in a design stage, where the product’s geometry has not yet been finally defined. Since such an early tolerance consideration allows quick and economic design changes seeking for robust designs, it is advisable that the design engineer, who is entirely familiar with the design, should take this step. For this purpose, this paper presents an easy-to-use CAD-based tolerance analysis method for skeleton models. The relevant part deviations are represented by varying geometric dimensions with externally driven family tables. The approach comprises the strength of vector-based methods but does not require an expensive set-up of tolerance analysis models. Particularly, the novelty of this method lies in the CAD-internal sampling-based tolerance analysis of simple geometries without the use of expensive CAT software. This enables designers to evaluate the effect of tolerances already at the preliminary design stage. Using a case study, the presented approach is compared with the conventional vector-based tolerance analysis.

[1]  J. Shah,et al.  Tolerance-Maps Applied to the Straightness and Orientation of an Axis , 2007 .

[2]  Jami J. Shah,et al.  Dimension and tolerance modeling and transformations in feature based design and manufacturing , 1998, J. Intell. Manuf..

[3]  Brigitte Moench,et al.  Engineering Design A Systematic Approach , 2016 .

[4]  Joseph K. Davidson,et al.  A mechanism for validating dimensioning and tolerancing schemes in CAD systems , 2001, Comput. Aided Des..

[5]  Sandro Wartzack,et al.  Concept for tolerance design in early design stages based on skeleton models , 2013 .

[6]  Zhao Feng-xia,et al.  Research on the Intelligent Annotation Technology of Geometrical Tolerance Based on Geometrical Product Specification (GPS) , 2015 .

[7]  Philippe Serré,et al.  Defining tools to address over-constrained geometric problems in Computer Aided Design , 2014, Comput. Aided Des..

[8]  Xiaojun Liu,et al.  Description logic-based automatic generation of geometric tolerance zones , 2015 .

[9]  Wilma Polini.  Taxonomy of models for tolerance analysis in assembling , 2012 .

[10]  Gaurav Ameta,et al.  Comparison of Spatial Math Models for Tolerance Analysis: Tolerance-Maps, Deviation Domain, and TTRS , 2011, J. Comput. Inf. Sci. Eng..

[11]  Christian Weber,et al.  Transforming ISO 1101 Tolerances into Vectorial Tolerance Representations — A CAD-Based Approach , 1999 .

[12]  Alex Ballu,et al.  A new Design Method based on Functions and Tolerance Specifications for Product Modelling , 2006 .

[13]  Pasquale Franciosa,et al.  Automatic evaluation of variational parameters for tolerance analysis of rigid parts based on graphs , 2013 .

[14]  Serge Samper,et al.  Tolerance Analysis and Synthesis by Means of Deviation Domains, Axi-Symmetric Cases , 2007 .

[15]  Rikard Söderberg,et al.  Robust design of aero engine structures: Transferring form error data when mapping out design spaces for new turbine components , 2016 .

[16]  Jean-Yves Dantan,et al.  Worst-case and statistical tolerance analysis based on quantified constraint satisfaction problems and Monte Carlo simulation , 2009, Comput. Aided Des..

[17]  Spencer P. Magleby,et al.  Generalized 3-D tolerance analysis of mechanical assemblies with small kinematic adjustments , 1998 .

[18]  Abdelmajid Benamara,et al.  An algorithm for CAD tolerancing integration: Generation of assembly configurations according to dimensional and geometrical tolerances , 2015, Comput. Aided Des..

[19]  Y. S. Hong,et al.  A comprehensive review of tolerancing research , 2002 .

[20]  Stephan Husung,et al.  Use of Vectorial Tolerances for Direct Representation and Analysis in CAD-systems☆ , 2015 .

[21]  Joseph K. Davidson,et al.  A Comparative Study Of Tolerance Analysis Methods , 2005, J. Comput. Inf. Sci. Eng..

[22]  Paul J. Drake,et al.  Dimensioning and Tolerancing Handbook , 1999 .

[23]  Hua Chen,et al.  A comprehensive study of three dimensional tolerance analysis methods , 2014, Comput. Aided Des..

[24]  Xuening Chu,et al.  Multi-skeleton model for top-down design of complex modular products , 2014, 2014 IEEE International Conference on Industrial Engineering and Engineering Management.

[25]  Nabil Anwer,et al.  Integrated Tolerancing Process for conceptual design , 2003 .