农用车辆半轴的保守模糊可靠度设计

从轻量化和强度安全性的角度出发,综合运用了概率密度函数联合积分法与功能密度函数积分法,整理并推导了农用车辆半轴的保守模糊可靠度计算公式,即应力、强度及构件的几何尺寸等参数都为正态分布,隶属度函数为七次抛物线分布时的模糊可靠度计算公式;通过VB编程实现农用车辆半轴保守模糊可靠度设计的数值解计算,根据输入的原始数据、原函数与积分区间的特点进行积分变换,然后利用中点公式积分法与龙贝格求积法进行积分计算.程序可直接应用于设计计算中,以提高农用车辆半轴的设计水平.

Conservative fuzzy reliability design of the semi-axle of agricultural vehicles

With considering light-weight and safety of strength, integrations of both probability density and function density, the conservative fuzzy reliability design formulas for the semi-axle of agricultural vehicles were deduced, in which forces, strengths, geometry dimension of component etc. were in normal distribution and subordinate function was parabola of exponential k. First, the numeric calculation of conservative fuzzy reliability for designing the the semi-axle of agricultural vehicles using Visual Basic was conducted, and the integral transform was achieved according to initial data and function imported and integrated extent. Second, the integral calculation of the conservative fuzzy reliability of the semi-axle of agriculture vehicles was made by using middle-points integral calculus and Romberg integration. This program can be directly used in design of the semi-axle of agricultural vehicles so as to raise design level.