Robust topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic field model

Abstract

This paper presents a new robust topology optimization framework for hinge-free compliant mecha- nisms with spatially varying material uncertainties, which are described using a non-probabilistic bounded field model. Bounded field uncertainties are efficiently represented by a reduced set of uncertain-but-bounded coefficients on the basis of the series expansion method. Robust topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material volume. The nest optimization problem is solved using a gradient-based optimization algorithm. Numerical examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms.

Key words： compliant mechanisms; robust topology optimization; hinges; uncertainty; bounded field

Acknowledgements

This work was financially supported by the National Key R&D Program of China (Grant No. 2017YFB0203604) and the National Natural Science Foundation of China (Grant No. 11472215).

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