Abstract: A parallel manipulator with three orientational degrees of freedom driven by pneumatic muscle actuators (PMA) is proposed. A fuzzy variable structure controller (FVSC) is designed on the basis of analyzing kinematics and dynamics of the parallel manipulator. The experiment shows that the maxi-mum error is 0.3 mm. When the air supply pressure is changed, the error is still less than 0.6 mm. The results demonstrate that the parallel manipulator driven by PMAs is appropriate and FVSC method is suitable for the parallel manipulator.

Key words: Fuzzy control, Parallel manipulator Variable structure control, Pneumatic muscle actuators