7自由度虚拟轴串并联机床概念设计

Concept Design of 7 DOF Series-parallel Machine with Virtual Axes

在基于6杆虚拟轴运动原理的复杂刀具曲面成型技术研究的基础上,将3杆并联机构进行扩展,获得了5自由度主轴头,进而构思了基于虚拟轴运动原理的7自由度串并联专用机床结构,并分析了该机构动平台的运动位姿及连杆的运动误差.该结构适当增加了绕机构中心的自由回转,所以极大地扩大了主轴工作空间,弥补了并联机构工作空间小的不足,提高了主轴头的灵活性.

Based on the study of curved surface forming technique of complicated tools, which was on the basis of movement principle of virtual axes with 6 arms, parallel mechanism with 3 arms was expanded. Consequently, the 5 DOF spindle head was obtained. Furthermore, an original series-parallel special machine with 7 DOF, which was based on the movement principle of virtual axes, was designed. Moving pose of the table and kinematic error of the arms were analyzed. A free turning around the center of the mechanism was additionally set up in this kind of structure. Therefore, it extended working space of the main spindle, and made up for limited working space of parallel mechanism. So it greatly improved the flexibility of the spindle head.