可用作虚轴坐标测量机的全解耦并联机构运动学分析

Kinematics analysis of complete decoupling parallel mechanism applicable to coordinates measuring machine with virtual axis

针对提出的一平移两转动全解耦并联机构易产生奇异位置及工作空间较小等不足,通过改变支链两移动副的位置,得到了一种改进型全解耦性质、自由度及运动输出保持不变的一平移两转动并联机构;给出了其运动位置的正逆解析解,得到并分析了工作空间形状及大小;与原机构在正逆解数、解耦性与工作空间形状及大小等进行了比较,证实改进型机构为一种优选机型,更适合于用作虚轴坐标测量机、机床及其他运动平台的实用机型。

Aimed at the deficiencies of smaller working space and easy to produce singularity positions for the being proposed one translation and two rotation complete decoupling parallel mechanism and by means of changing the positions of two translation pairs of the branch chain, a kind of improved one translation and two rotation parallel mechanism , with a property of complete decoupling, degree of freedom and output of movement maintaining invariable, was obtained. The forward and inverse solutions of its movement positions were presented, and the shape and size of working space were obtained and analyzed. A comparison was carried out with the original mechanism on the number of forward and inverse solutions, decoupling-ness and shape and size of working space etc. It has been proved that the improved mechanism is a kind of optimummechanism, and is more suitable to be applied to the practical model such as coordinates measuring machine with virtual axis, machine tools and other moving platforms.