Defining a Workspace Without Singular Configurations of 3-PRRS Type Tripod

3-PRRS tripod type parallel manipulator is formed by connecting the moving and fixed platforms through three legs of PRRS type, where P, R, and S denote the prismatic, revolute, and spherical kinematic pairs, respectively. The 3-PRRS type tripod has three active rotational and three passive translational DOFs. In this paper a workspace without singular configurations of the 3-PRRS type tripod are defined. Constraints on the movement of the moving platform are derived. Dependent and independent parameters for determining the movement of the moving platform are obtained. Jacobi matrices relating the velocities of the moving platform and input links are derived, and a workspace without singular configurations is determined.