椭圆柔性铰链疲劳失效分析与寿命预测

Fatigue Failure Analysis and Life Prediction of Elliptical Flexible Hinge

针对柔顺机构中柔性铰链受到交变对称循环载荷的作用下,使柔性铰链最薄弱处容易产生应力集中,导致柔性铰链疲劳失效问题,以柔顺机构中椭圆型柔性铰链为研究对象,以材料力学中纯弯曲理论为基础,推导椭圆柔性铰链切口处最大集中应力计算公式;利用ANSYS仿真分析,对比验证了计算公式的准确性与可行性;在此基础上,通过引入线性回归方法,建立椭圆型柔性铰链寿命预测模型,既可以预测椭圆型柔性铰链的疲劳寿命,也可以解决疲劳失效问题。通过实例验证了该模型的正确性与有效性,可为其他类型柔性铰链的疲劳失效与寿命预测提供重要参考。

For the flexible hinge of compliant mechanism under the action of alternating symmetrical cyclic load, the stress concentration in the weakest area of the flexible hinge is easy to cause, resulting in the fatigue failure of the flexure hinge,taking the elliptical flexible hinges in compliant mechanisms as the research object, based on the theory of pure bending in material mechanics, the calculation formula of maximum concentrated stress at the notch of an elliptical flexure hinge is derived. By using the ANSYS software, the accuracy and feasibility of the calculation formula are verified. On this basis, by introducing linear regression method, the life prediction model of elliptical flexure hinge is established, which can predict the fatigue life of elliptical flexure hinge and solve the fatigue failure problem. Finally, an example is given to verify the correctness and effectiveness of the model, an important reference for fatigue failure and life prediction of other types of flexure hinges is provided.