A Hierarchical Approach for the Verification and Validation of Tolerance Analysis Models

Abstract

Established tolerance analysis methods are capable of predicting the effects of geometrical part variations on the quality of products and hence virtually assuring their functionality. However, assumptions and simplifications are often made, which can lead to decisive uncertainties. To omit a significant effect of these uncertainties on the overall model and on the obtained results, both a virtual assessment of the model as well as an experimental validation are necessary. The current state of the art still lacks suitable methods and metrics to reliably evaluate the results of tolerance analyses. In addition, an approach is needed to investigate and evaluate the effects of uncertainties within the analysis model on the overall model. The aim of this contribution is therefore to derive statements about the suitability and significance of methods and metrics of verification and validation for evaluating simulation models and their feasibility in the context of tolerance analysis. First, general methods and metrics for the evaluation of simulation results are presented. Subsequently, the most promising ones are customized in an unifying approach. The statistical tolerance analysis of a 3-D-printed non-assembly mechanism in motion serves as an explanatory example for highlighting the procedure and the current challenges and constraints. Finally, the findings are critically discussed and as a result, statements about the further need for action are presented.