摘要
在一台非冗余4自由度并联机床上添加一条具有主动驱动的冗余支链,构造4自由度驱动冗余并联机床,研究其控制策略。基于相应的非冗余并联机床的位置控制,对冗余机床的冗余支链采用力控制方式以控制冗余支链的内力,其他运动支链采用位置控制以保证机床的运动精度。在推导出控制系统传递函数的基础上,分别分析控制系统的稳定性、抗干扰能力和响应性能。最后将位置/力控制方式集成到冗余机床的数控系统中,并进行试验研究。通过机床沿圆形轨迹运动的轮廓误差试验证明此控制方式可以保证冗余并联机床和对应的非冗余机床具有相似的轮廓误差,而且冗余支链减小了非冗余伸缩支链中的间隙,从而证明了冗余支链力控制工程的有效性和可行性。
The control strategy of a 4-DOF parallel kinematic machine （PKM） with actuation redundancy, which is created by adding a redundant link with active actuator to a corresponding non-redundant PKM, is studied. Based on the position control of the corresponding non-redundant PKM, the redundant chain is controlled by using force mode to control the internal force of the redundant chain, and other kinematic chains are controlled by using position mode to ensure the motion precision of the redundant PKM. Based on the transfer function of the control system, the stability, anti-disturbance capability and response performance are studied. Further, the control strategy is applied to the numerical control system and the experiment is carried out. The contour test with the PKM moving along a circular trajectory shows that the contour error of the redundant PKM is similar to that of the corresponding non-redundant one. In addition, the clearance in the non-redundant extendible chain is reduced due to the existence of the redundant chain. Thus, the engineering effectiveness and feasibility of the control strategy are verified.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2009年第9期152-157,共6页
Journal of Mechanical Engineering
关键词
驱动冗余
并联机床
力控制
Actuation redundancy Parallel kinematic machine Force control
