基于鞍点逼近的机械结构可靠性稳健优化设计

将可靠性优化设计理论与可靠性灵敏度分析方法相结合,讨论了机械零部件稳健优化设计的问题.系统地推导了基于鞍点逼近的可靠性灵敏度公式,并把可靠性灵敏度计算结果融入可靠性稳健优化设计模型之中,将可靠性稳健优化设计归结为满足可靠性要求的多目标优化问题.在基本随机参数概率分布已知的前提下,应用鞍点逼近技术,得到极限状态函数的分布函数与概率密度函数,并且将此结果应用到机械零部件的可靠性灵敏度分析中,进而实现了机械零部件的可靠性稳健优化设计.通过与Monte-Carlo方法计算所得的结果相比可知,应用鞍点逼近技术可以迅速、准确地得到机械零部件可靠性稳健设计信息．

Reliability-based robust optimization design for mechanical structural by saddle point approximation

Combining the reliability-based optimization design theory with the reliability sensitivity analysis method,the reliability-based robust optimization design is extensively discussed.Based on the saddle point approximation theory,the reliability sensitivity formula was derived systematically.The reliability sensitivity was added into the reliability-based optimization design model,and then the reliability-based robust optimization design was described as a multi-objective optimization.Based on the premise that the probability distribution of random parameters had been known,the cumulative distribution function and the probability density function of the limit state function were obtained by the saddle point approximation method,and the result was applied into the reliability sensitivity analysis of machine parts.Finally,the reliability-based robust optimization design was completed.According to the result compared with the result obtained by Monte-Carlo method,it is known that the design information can be acquired accurately and quickly.