弹性连杆机构广义刚度可靠性分析的数值模拟法

Numerical simulation method for random-fuzzy reliabilityanalysis of elastic linkage mechanism stiffness

首先对响应面法进行了改进并应用于弹性连杆机构刚度可靠性分析,以迭代的格式和选择最优插值点的响应面法确定弹性连杆机构刚度可靠性分析的极限状态函数,编制了相应的有限元程序。然后在考虑安全、失效状态模糊性的基础上建立了弹性连杆机构的广义可靠性分析模型;提出了以重要抽样法与描述性抽样法相结合来求解弹性连杆机构广义失效概率的方法,此方法可以大量减少抽样时间,并且可以大大提高抽样效率,从而加快结果的收敛速度。

The response surface method is improved and used in the stiffness reliability analysis of elastic linkage mechanisms, for which the limit state function is determined iteratively, and the precision can be guaranteed by the selection of optimal interpolation points and iterative pattern. The finite element method for response surface limit state function of the elastic linkage mechanism stiffness has been programmed. Based on the suggested response surface limit state function, the random-fuzzy reliability model is set up by taking the fuzziness of the safety state into consideration. The importance sampling method is combined with the descriptive sampling method to simulate the random-fuzzy failure probability. It can decrease the time for sampling and increase the sampling efficiency, and so make the simulation converge rapidly.