T2R1-type parallel manipulators with decoupled and bifurcated planar-spatial motion of the moving platform

This paper presents a new family of T2R1-type parallel manipulators with decoupled and bifurcated planar-spatial motion of the moving platform. The moving platform has two independent translations and one rotation driven by three actuators mounted on the fixed base. The bifurcation between planar and spatial motion occurs in a constraint singularity in which the connectivity between the moving and the fixed platforms increases instantaneously with no change in limb connectivity. The Jacobian matrix of solutions presented in this paper is a 3 times 3 triangular matrix in the entire workspace of each branch with planar or spatial motion of the moving platform. This paper presents for the first time a family of parallel manipulators with decoupled and bifurcated planar-spatial motion of the moving platform.