科创中国

原文链接：万方

• 摘要：

  The existing researches on singularity of parallel mechanism are mostly limited to the property and regularity of singularity locus and there is no further research into the geometric relationship between uncontrolled kinematic screw and parallel mechanism in singularity.A 3UPS-S parallel mechanism is presented which fulfils 3-DOF in rotation.The regularity of nutation angle singularity is analyzed based on the Jacobian matrix,and the singularity surface of 3UPS-S parallel mechanisms is obtained.By applying the concept of reciprocal product in screw theory,the singular kinematic screw is derived when 3UPS-S parallel mechanism is in singularity.The geometric relationship between singular kinematic screw and singular configuration of 3UPS-S parallel mechanism is investigated by using programs in MATLAB.It is revealed that there are two kinds of situation.Firstly,the three limbs of 3UPS-S parallel mechanism intersect the singular kinematic screw in space simultaneously;Secondly,two limbs cross the singular kinematic screw while the third limb parallels with that screw.It is concluded that the nutation angle singularity of 3UPS-S parallel mechanism belongs to the singular linear complexes.This paper sheds light into and clarifies the geometric relationship between singular kinematic screw and singular configuration of 3UPS-S parallel mechanism.

• 关键词：

  parallel mechanism condition number of Jacobian matrix screw theory singular linear complexes

• 作者单位：

  College of Mechanical Engineering and Automation, Beihang University, Beijing 100191, China

• 基金项目：

  Aeronautical Science Foundation of China (Grant20081651025)

• 来源期刊：

  中国机械工程学报

• 年，卷(期)：

  201427001