Study On A Square-Ring TypeLinear Standing Wave Motor

The linear Ultrasonic motor is a new type of actuator that uses mechanical vibration in the ultrasonic range as its source, the energy is transformed by contact friction. At last, linear displacement is output. As a main branch of the USM, it takes on many advantages. In recent years, with the rapidly development of automatic control and microcomputer, the higher need has been put forward about precise position of autocontrol system. Therefore, more and more countries are engaging in research and development of linear USM all over the world, which will make for the linear USM is applied widely.Based on a ring type of traveling wave USM, a new linear piezoelectric driver with square-ring vibrator is presented in this paper. The vibrator has two contact surfaces, and is connected to the support parts by flexure hinges. This framework integrated the vibrator with the support.Different from the same type of other USM before, its main characteristic is that the vibrator takes a pair of bending modes in-plane with the same order and the same frequency to realize the motor's movement of both forward and backward, and simplify the drive circuit.In this paper, working principle of the linear USM is analyzed theoretically, the vibrator's dynamic design is studied by using finite element method, also the main structure parameters that influence the vibrator's mode and natural frequency is analyzed. In addition, the prototype is manufactured to verify the validity of theory. These will offer reference of the following USM design.