环形轨道平台位姿调整3-RPR平面并联机构尖点及无奇异路径规划

Cusp and Singular-Free Path Planning of 3-RPR Planar Parallel Mechanism for Position Adjustment of Ring Track Platform

为保障核电站运行安全,需要在线检测核主泵中空螺栓的疲劳失效、腐蚀、裂纹等缺陷。环形轨道平台是核主泵中空螺栓检测装备的运行基准,其与核主泵同心度调整的3-RPR平面并联机构路径规划是保证检测精准的核心技术。构建了3-RPR约束方程、雅可比行列式和雅可比增广矩阵的子矩阵行列式组成的尖点方程组,消元得到了一个24次变元多项式,确定了关节空间内的所有尖点数量。利用3-RPR平面并联机构关节空间内的尖点,规划了同一无奇异最大域中装配构形间的无奇异路径;结果表明,该方法增加了机构可控工作空间,对并联机构运动学有重要的研究意义。

In order to ensure the safety of nuclear power plant operation,the fatigue failure,corrosion,cracks and other defects of the hollow bolts of the nuclear main pump should be detected online.The ring track platform is the operating basis of the hollow bolt detection equipment of the nuclear main pump,and the path planning of the 3-RPR planar parallel mechanism with the concentricity adjustment of the nuclear main pump is the core technology to ensure detection accuracy.Cusp equations composed of 3-RPR constraint equations,Jacobian determinant and submatrix determinant of Jacobian augmented matrix are constructed.A 24-degree variable polynomial is obtained by elimination,and the number of cusps in the joint space is determined.Using the cusps in the joint space of the 3-RPR planar parallel mechanism,the non-singular paths between the assembly configurations in the same non-singular maximum domain are planned.The results show that this method increases the controllable working space and has important research significance for the kinematics of parallel mechanism.