基于鞍点逼近的车辆零部件可靠性优化设计

将可靠性理论与优化技术相结合,讨论了车辆零部件的可靠性优化设计问题,提出了可靠性优化设计的数值计算方法.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,得到了外载荷作用下随机响应的概率密度函数和分布函数.通过与Monte-Carlo方法对比分析,可知利用该方法得到的计算结果精度高,并且计算速度快.因此用鞍点逼近法计算车辆零部件的可靠度为车辆零部件的可靠性优化设计奠定了理论基础,保障了在车辆零部件的可靠性优化设计中迅速、准确地得到车辆零部件的设计信息.

Reliability-based Optimization Design of Vehicle Parts by Saddlepoint Approximation

Combining the reliability theory with optimization technique, the reliability-based optimization design for vehicle parts is emphatically discussed, then a numerical method is proposed for the reliability-based optimization design. Based on the premise that the probability distribution of random parameters has been known, the probability density function and probability distribution function of random structural response under external loading are accurately and quickly obtained by way of saddlepoint approximation and, as a result, the saddlepoint approximation method is proved accurate with higher computing speed in comparison with the Monte-Carlo method. Therefore, the reliability of vehicle parts computed by the saddlepoint approximation lays a theoretical foundation for the reliability-based optimization of vehicle parts, and it can accurately and quickly acquire the design information.