【摘要】 以工程中实际应用的某压力机平面多连杆机构为例,分析了其运动方程,得到了其运动精度可靠性分析的功能随机过程。采用极值变换理论,构造了机构运动精度极值概率演化的虚拟随机过程。利用概率密度演化方法求解得到了响应极值的概率密度函数,概率密度演化方法可直观地反映机构运动精度响应量与输入随机变量的概率演变、转化关系,并可方便地求解出机构运动精度可靠度。最后,结合计算结果分析了概率密度演化方法在机构运动精度可靠性分析中应用的优越性和可能存在的问题。更多还原

【Abstract】 A planar multi-linkage mechanism of a compressive machine is taken as an example for studying the reliability of mechanism kinematic accuracy.Its motion functions are analyzed;its performance random processes of the kinematic accuracy reliability are obtained.Employing the extreme value transformation theory,virtual random processes are constructed for obtaining the probability density function of the extreme values by the probability density evolution method.The probability density function evolution of the extreme values can objectively reveal the evolution and the transformation relation between the kinematic accuracy responses and the input random variables of the mechanism.Based on the probability density functions of the extreme values,the mechanism kinematic accuracy reliability can be computed.Finally,the calculation results are used to analyze the advantages and possible difficulty of the probability density evolution application in the reliability analysis of the mechanism kenemaitc accuracy.更多还原