含运动副间隙平面轨迹机构的可靠性设计

Reliability Design of Planar Path Mechanism with Joint Clearance

针对平面轨迹机构,提出一种同时考虑尺寸公差和运动副间隙的机构可靠性设计方法。首先应用截尾降维方法处理机构运动误差函数中的运动副间隙变量,以此建立机构各输出分量的误差概率模型,并以各运动分量误差的联合概率密度函数求解机构运动的综合可靠度。在此基础上,建立以机构结构误差最小为目标和机构运动的综合可靠度为约束的机构可靠性设计模型。最后给出数值实例对所提方法的有效性进行验证。

For planar path mechanism, a novel reliability design method is proposed with dimension tolerance and joint clearance. Considering the mechanism with joint clearance, a hybrid dimension reduction method （HDRM） is adopted to handle the joint clearance variables in kinematic error function. A probabilistic model of per output component error is then established. The joint probability density function of the output components is used to estimate the composite mechanism kinematic reliability. A reliability design model of the planar path mechanisms is established which objective is to minimize the structure error and the kinematic composite reliability is introduced to the constraints. A numerical example is given to illustrate the effectiveness of the proposed method.