Property Identification of the Singularity Loci of the 6/6-Stewart Manipulator

This paper addressed the problem of identifying the property of the singularity loci of the 6/6-Stewart manipulators. The singularity locus equation of the manipulator can be obtained by setting the determinant of the Jacobian matrix be zero. The singularity loci for different orientations are illustrated with examples. The singularity locus equation of the manipulator with respect to the oblique plane is derived either which is a polynomial expression of two degree. It shows that the singularity loci of the manipulator in the parallel oblique planes are hyperbolas accompanied with four pairs of intersecting straight lines and a parabola. Their geometric interpretations and the properties of the singularity loci are further analyzed.