We have proposed a mechanism and control method of a high speed parallel mechanism with driving force redundancy. However, when such a parallel mechanism is driven at high speed, it has the possibility to produce large internal forces. In order to reduce such internal forces, we have proposed the method of introducing kinematical redundant degrees of freedom into such a parallel mechanism. Furthermore, we suppose that high accurate motions can be realized by applying the control method we proposed to the mechanism. In this paper, we verify how the mechanism and the control method can reduce the internal forces and realize high accurate motions by experiments.