含运动副间隙的平面函数机构运动点可靠性分析

摘要

Joint clearance is the most important uncertainty to affect on kinematic and dynamic per-formance of mechanisms . To accurately evaluate the kinematic reliability of mechanisms with joint clearance ,the key is to create reasonable and effective probabilistic model of joint clearance . Taking the function generator mechanisms with joint clearance for example ,the structure error and random error were considered to create the motion error function of mechanisms .The Cut Hybrid Dimension Reduction Method was applied to handle the correlation of joint clearance vari-ables and then the equivalent probabilistic model of motion error was established .The First Or-der and Second Moment method was used to solve the point kinematic reliability of the mecha-nisms .The results show that the Cut Hybrid Dimension Reduction Method is validation for sol-ving kinematic reliability of planar function mechanisms with joint clearance when the structure error and random error are considered .%运动副间隙是影响机构运动与动力性能的一类最重要的不确定性。为精确估计含运动副间隙的机构运动可靠度，建立机构运动间隙合理、有效的概率模型是关键。为此，以含运动副间隙的函数生成机构为例，在其运动误差函数中综合考虑机构的结构误差和随机误差，应用截尾混合降维法对运动副间隙变量进行处理并建立机构运动误差的概率等效模型，采用一次二阶矩法实现等效模型的求解。数值实例验证了截尾混合降维法在考虑结构误差和随机误差含运动副间隙的函数机构运动可靠性分析中的有效性。