摘要
奇异性是并联机构的固有属性,对机构的工作性能会产生不良影响,针对确定的并联机构应找出它的奇异位形.本文对驱动器分别布位于主动支链移动副和胡克铰2个转动副的3种驱动形式的Tricept并联机构的奇异性进行了分析.首先基于螺旋理论推导了机构各支链的运动螺旋系,利用互易积获得约束子矩阵和运动子矩阵,以此为基础建立了机构的完整雅克比矩阵.根据完整雅克比矩阵及线几何理论分析了Tricept并联机构的位形奇异条件,给出了3种驱动形式下Tricept并联机构的奇异位形,并分析了机构在奇异位形处的运动特征.
Since singularity is the inherent characteristic of parallel mechanism and has bad effects on manipulator's working performance, for a certain mechanism, its singular configures should be found out. The paper chooses the Tricept parallel mechanism, analyzing the singularity in three different actuator dispositions, including a prismatic pair and two revolute pairs of the universal joint, of the Tricept. First, the systems of twists and reciprocal screws of the limbs of the Tricept are deduced based on the scerws theory. Second, the constraint sub-matrix and actuation sub-matrix are obtained through the orthogonal product, and the complete Jacobian matrix of the Tricept is obtained. Finally, the singular conditions of the parallel mechanism are analyzed by investigating the rank of the Jacobian matrices and the theory of Grassmann line geometry, and the singular configures of three actuator dispositions of the Tricept and their kinematic characteriscs are obtained.
出处
《北京工业大学学报》
EI
CAS
CSCD
北大核心
2011年第1期19-26,共8页
Journal of Beijing University of Technology
基金
国家自然科学基金资助项目(60275031)
北京市重点实验室开放基金资助项目(JH001011200801)