Abstract—Novel four-dof (three-translation and one-rotation) gantry type parallel robot driven by a differential belt and a differential screw is proposed in this paper. Single side timing belt was installed in the conventional research, which restricts arrangements of pulleys on the robot. The restriction of the arrangement of pulleys is eliminated by the double-sided timing belt. In order to eliminate the design limitation by using off-the-shelf spline-screw, our novel differential cylindrical drive by Gaudi-screw is installed in the moving part. Workspace of the robot is limited because no longer looped timing belt is off-the-shelf. Novel belt arrangement is proposed for enlarging the workspace by multiple looped timing belts. Linux CNC was customized for the first prototype.