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

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 increase the sampling efficiency, so the simulation converges rapidly.