一种可重构空间四杆机构

摘要

提出一种可重构空间四杆机构,其具有两种不同的工作模式,模式Ⅰ为一个转动运动,模式Ⅱ为一个平移平动,两种运动模式进行切换的初始位形具有瞬时的一个转动和一个平动.将可重构空间四杆机构与一个具有两移动和两转动的串联支链相连,构成一种具有两种不同工作模式的可重构混联支链.利用3条可重构混联支链连接并联机构的固定平台和运动平台,可得到一种新型可重构并联机构,通过控制3条可重构混联支链分别在两种不同工作模式间切换,可重构并联机构可实现4种不同的三自由度运动模式.利用螺旋理论分析和证明了上述结论.%A reconfigurable spatial four-bar mechanism with two different operation modes is proposed.The mechanism has one rotational motion mode,one translational motion mode,one rotational and translational motions mode in the initial configuration where the mechanism can transit from one operation mode to another,respectively.Reconfigurable hybrid chain with two distinct phases is obtained by integrating the reconfigurable spatial four-bar mechanism with serial limb that has two translational and two rotational motions.A new kind of reconfigurable parallel mechanism is constructed with three identical hybrid chains connecting the fixed base and the moving platform.By controlling the three hybrid chains move into different motion modes,the reconfigurable parallel mechanism has the ability to perform four kinds of motion with three degree of freedom(DOF).The special mobility of the mechanisms are analyzed and proved by using the screw theory.