Fatigue analysis and life prediction of elliptical hyperbolic hybrid flexure hinges

For the problem of fatigue failure of flexure hinge under symmetric cyclic loading due to stress concentration at the weak point of the notch, this paper takes the elliptical hyperbolic flexure hinge in the fast steering mirror as the research object, determines the failure position through finite element analysis, and deduces the maximum stress calculation formula. A fatigue life prediction model is constructed based on the stress-life model, and the Marin method is introduced to correct the fatigue strength. Examples verify the correctness and validity of the model, and the size of the element size with acceptable accuracy in the simulation is discussed, which can provide references for the fatigue analysis of similar flexure hinges.