Kinematic performance and singularity analysis for a spatial parallel manipulator

A novel 5-5R fully-symmetrical parallel mechanism is introduced firstly. Then the kinematic performance is analysed by using screw theory .Two kinds of limb singular configurations are found by using geometry principles for judging reciprocity of special screws. When the plane determined by parallel axes of two rotating joints passing through the common intersect of the other three axes of rotating joints, the limb singular configurations will occur. On the other hand, if the three intersectional axes of rotating joints are coplanar, the limb singular configurations will occur too. The determination of singular configurations is critical to understanding a parallel manipulator´s kinematics and can be important in the implementation of controller for manipulator.