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A multi-DOF ultrasonic motor in two orthogonal and a radial bending mode was proposed.The optimum match criteria of the two kinds of vibration modes were deduced.The four feet of the proposed multi-DOF ultrasonic motor drive consistently.A new kind of measure system for multi-DOF ultrasonic motor was designed.Max torque and speed of 0.118 N m and 55 r/min are achieved at a voltage of 35 Vrms.A new type of multiple-degree-of-freedom (multi-DOF) ultrasonic motor was developed aiming at high output torque and compact structure. To reach this purpose, a ring type composite stator was proposed with four driving feet uniformly arranged in the inner circumference of the ring stator. The stator employs two orthogonal axial bending modes and a radial bending mode, by exciting two of them simultaneously, to generate elliptic trajectories on driving feet tips and to push sphere rotor around x, y and z axis respectively. Based on the deduced criteria, a specific combination of the A(0, 5) axial bending modes and R(0, 2) radial bending mode were chosen to realize that the rotating directions of the elliptical driving trajectories on four feet tips can push the sphere rotor to spin in the same direction consistently, thus the efficiency and output performance will be improved by decreasing the slip between feet and rotor. FEM was used to design the motor including selecting key parameters to tune the resonant frequencies by sensitivity analysis, and a prototype was fabricated and tested. The experiment results showed that the maximum output torque of the motor is 0.118 N m and the maximum speed is 55 r/min.