不同转动副间隙对曲柄群驱动机构的动力学特性影响研究

Research on Dynamics Characteristic Influence of Different Clearance of Rotating Pair on Crank-group Driving Mechanism

曲柄群机构是一种含有冗余约束的连杆桁架驱动机构。针对机构特性,在采用“连续接触模型”的动力学模型基础上,以6个曲柄的曲柄群机构为例,建立机构虚拟仿真模型,利用Adams对转动副间隙半径不同时的机构动力学特性进行了研究。结果表明,在一定的要求精度范围内,转动副间隙大小对从动构件的位移和速度的整体影响不大,但对从动构件加速度和接触力影响明显;转动副间隙半径设置越大,从动构件加速度和运动副接触力振荡幅值越小,振荡频率越大。

The crank-group driving mechanism is a kind of linkage truss mechanism with redundant con⁃straints.Aiming at the mechanism characteristics,based on the dynamics model of‘continuous contact mod⁃el’,a virtual simulation model of the crank-group mechanism with six cranks is established,and the dynamics characteristics of mechanism with different clearance radius of rotating pair are studied by using simulation software Admas.The results show that,in a certain range of required accuracy,the clearance size of the rotat⁃ing pair has little effect on the displacement and velocity of the driven component,but has obvious effect on the acceleration and contact force of the driven component.With the larger clearance radius of the rotating pair,the smaller the amplitude of the vibration of the acceleration and contact force of the driven component,the larger the oscillation frequency.