Research On The Traveling-Wave Type Ultrasonic Motor With Harmonic Drive

The traveling-wave type ultrasonic motor (TWLTSM) has been put into application in the fields of robot, instrumentation, industrial control, precision positioning and aerospace for its high torque, low speed and smooth operation. From the research and development of the TWUSM, the trend of the TWUSM is to acquire high-torque, high precision, high stability and high reliability. But there is a little research on supper-low-speed, which is studied in this paper. In order to improve the performances and accelerate the practical process of the TWUSM, several key technologies, such as the driving model, the friction and the noise mechanism, the structure design, the manufacture craft, etc, should be studied deeply and systematically in this thesis. The research work and the creative achievements of the thesis are as follows:We study traveling wave ultrasonic motor mainly on this paper. Firstly, the history, classification, features and the applications of USM are introduced simply. Based of these, the task of this paper is proposed.The work principle for drive of harmonic friction is researched. The first one is to proved the existence of the oval sport track, according to sub- surface particle sport analysis, and deduced the formation mechanism of traveling wave at the same time. Analyzed the drive power according to build up the motor power contact model. Finally analyzed inside drive principle of the USM and give the transmission formula.There is a key introduction of the USM structure design, and also give the move process of the USM. On the bases of this, design each part. Mainly calculate and design the important parts, such as the stator, the rotor and the soft wheel. And then simply introduce the technics making process.Analysis software such as ANSYS is fully used in the soft wheel touch analysis and the stator composite board mode analysis of USM stator with its model tool and finite element method. Research the stress changing of the soft wheel by the touch analysis. Confirm the stator composite board mode frequency through the mode analysis. Provide basis for impedance analysis apparatus on drive frequency and polarization subarea of piezoelectric ceramic, which support the theory and experimentation foundation for mend of USM structure.Series of TWUSM prototypes are successfully based on the theories and experiments. All the researching results can improve the performances and propel the practical process of the TWUSM in our country.