Abstract
To overcome the problem of frequency consistency and simplify the design process of linear ultrasonic motor, a novel traveling wave linear ultrasonic motor with a ring-type stator is proposed in this paper. The combination of two orthogonal bending vibration modes with the same order is selected as the operating mode of the motor. A traveling wave along the side of the stator is utilized to drive the slider to move linearly. The stator adopts a ring symmetrical structure, which can effectively ensure that the resonance frequencies of the two vibration modes are consistent. Thus, we do not need to tune the frequencies of the two vibrations by constantly adjusting the shape of the stator or designing complex clamping parts to fix the stator without making any influence on the vibrations. Meanwhile, a three-dimensional finite element model of the motor is built. Using the model, we obtain the elliptical motion trajectories of the stator driving surface, the output performance of the motor, the sticking-slipping-separation contact characteristic between the stator and the slider and fabricate and measure a prototype of the proposed motor.