Abstract: A novel approach to formulate the closed form solution to orientation workspace of 6-PSS parallel manipulators is developed. Based on the definition of orientation workspace, the manipulator is visualized as aix factitious kinematic chains subject to the closed-loop constraints. Utilizing the orthogonal property of the relation velocity (angular velocity) between two jointed moving parts, method is proposed to determine the closed form solution to the orientation workspace. The influence of the dimensional parameter on the orientation capability of the mobile platform is also discussed.

Key words: Closed form solution, Orientation workspace, Parallel manipulators