Singularity analysis of redundant parallel manipulators

The general methods of singularity analysis of a general parallel manipulator are not suitable for that of a redundant parallel manipulator, thereby This work presents a method for the identification of the singularities of redundant parallel manipulators. Firstly, the theory of singular value decomposition is employed to analyze the velocity equation of a mechanism, and the relationship between the generalized input velocities and the generalized output velocities is researched. Then the physical interpretation of the singularity of a redundant parallel manipulator is discussed, and the relationship between the singularity and the singularity values of the Jacobian matrix of a mechanism is studied. Finally, based on above analysis, the singularities of a redundant manipulator are divided into three basic types and a method for computing the singularity set is presented and formulated. As an example, a 3 degree-of-freedom redundant manipulator is researched through using this method, and all the singular configurations of this manipulator are found out and pictured.