Master-slave active robot hands and endoscopes, which provide dexterous manipulations and wide views like human hands and eyes, are required to be constructed. We have previously developed a multi-DOF ultrasonic motor consisting of a spherical rotor and a bar-shaped stator. The rotor rotates around three perpendicular axes using three natural vibration modes of the stator. In this study, a mult...

Endoscopes for industrial and medical fields are expected to have multi degree-of-freedom (DOF) motions. A multi-DOF ultrasonic motor we developed consists of a spherical rotor and a bar-shaped stator, and the rotor rotates around three perpendicular axes using three natural vibration modes of the stator. In this study, a multi-DOF unilateral master-slave system for active endoscope using the m...

Aiming at the nonlinear characteristic of ultrasonic motor, some control strategies have been proposed to control the rotating speed of ultrasonic motor. But most of these strategies are too complex to realize using a low-cost embedded device. In this paper, a simple fuzzy speed controller is designed for ultrasonic motor. Until now, there has no mature and theoretic design method of fuzzy cont...

This paper reviews recent developments of micro ultrasonic rotary motors using piezoelectric resonant vibrations. Following the historical background, four ultrasonic motors recently developed at Penn State University are introduced; windmill, PZT tube, metal tube, and shear-type motors. Driving principles and motor characteristics are described in comparison with the conventional ultrasonic mo...

A multi-degree of freedom (multi-DOF) ultrasonic motor is anticipated as an actuator for the next generation because it can drive three-DOF motion with high torque and low noise. Before a multi-DOF ultrasonic motor can be used as a servomotor in actual robots, we have to develop a proper pre-loading mechanism and control algorithm for quick multi-DOF motion. This paper proposes a pre-loading me...

A vacuum environment is indispensable for various measurement devices. To make the use of these devices easy, the mechatronics systems for vacuum conditions, for example, a sample stage, should be advanced. In this paper, we propose a rotational feedthrough using an ultrasonic motor. An ultrasonic motor has many advantages, and is suitable for achieving vacuum conditions. However, the piezoelec...