Applying Sensitivity Analysis and Robustness Evaluation in Virtual Prototyping on Product Level using optiSLang

Reliability of portable devices becomes a serious issue as complexity of the devices grows and miniaturization trend continues. In case of dynamic applications durability against impact on hard surfaces is a standard requirement for mobile electronic devices, verified in drop tests. Computer Aided Engineering (CAE) methods and tools are used as means to accelerate the overall design cycle and to reduce time to market. In case of drop test simulations it is an important task to assess quality of simulation models and effect of different input parameters on results. Strong nonlinearities (contact, material, geometric) and large number of parameters involved make such sensitivity studies more difficult. It is also necessary to include effect of stochastic nature of input parameters which requires a robustness evaluation of the simulation models. This paper describes first results of a research project on development of an automated procedure of sensitivity analysis and robustness evaluation of product level simulation models used for drop test simulation. Several goals have been pursued with development of the methodology: to estimate the scatter of important design responses, to find out the most important input variables affecting important design responses both in sensitivity and robustness evaluation studies; investigate quality of simulation models in terms of explainability of the response scatter with correlations to scattering input variables. First results of the sensitivity and robustness evaluation studies have shown that the methodology can be used by Nokia at the product level. Additional verification with test results is required.