METH0D USED IN SINGULARITY RESEARCH BASED 0N KINEMATICS AND ITS EXAMPLE IN APPLICATION

摘要

＜正＞ First the kinematic principle of singularity is proved, that is the intersecting point of threenormal planes of three velocities at three non-collinear points in a rigid body lying in the plane determined by the three corresponding points. It is a sufficient and necessary condition that the velocities ofthree non-collinear points in a rigid body can determine a screw motion of the body Based on thisprinciple, a simple and direct new method to distinguish the singularity of the parallel manipulator islered. Wth this new kinematic method, the 3-RPS parallel manipulator is studied. Its singularity lociare obtained for some orietations for the first time and verified with Grassmann line geometry andscrew theory and the force Jacobian matrix.