Abstract: In order to avoid the degradation of mechanism performance caused by uncertainties in the process of manufacture and use, a new reliability-based topology optimization method for compliant mechanisms using the foundation structure approach is presented. Frame elements are chosen to represent the design domain because they are capable of capturing the bending modes. The applied load and the structural geometry size are considered as random variables, and the failure model of the mechanism is regarded as the series system of strain energy and mutual potential energy. The first-order reliability method is adopted to calculate the failure probability of the series system. The dual mathematical model of reliability-based topology optimization for compliant mechanisms is established, the dual algorithm is used for the optimization problem. The numerical example is simulated to show that the proposed method is correct and effective because it helps to obtain mechanisms with higher reliability than those obtained by the deterministic topology optimization.

Key words: Compliant mechanisms, First-order reliability method, Foundation structure approach, Reliability, Topology optimization