基于有限元法的驻波型直线超声波电机振动特性分析

采用有限元法研究一种驻波型直线超声波电机的振动特性。建立了电机的三维有限元模型,在有限元模型的基础上对电机进行模态分析,得到了电机横向一阶弯曲振动的共振频率,并分析了驱动足的位置对共振频率的影响。在模态分析的基础上,给电机通以高频交流电进行谐响应分析,研究电机在外加电源作用下的横向弯曲振动的振幅以及驱动足尖的运动轨迹。制作了驻波型直线超声波电机样机,对样机进行阻抗-频率特性测试,测试结果验证了理论分析结果。

Dynamic Analysis of Standing Wave Type Linear Ultrasonic MotorBased on Finite Element Method

The dynamics of a standing wave type linear ultrasonic motor was studied based on finite element method. The threedimensional finite element model of the motor was established, based on which the modal analysis was conducted. The resonance frequency of the first order transverse bending vibration was obtained, and the impact of the driving feet position on the resonance frequency was analyzed. On the basis of modal analysis, high frequency alternative current was then applied to the motor, and harmonic analysis was conducted. The amplitudes of transverse bending vibration stimulated by the applied source as well as the trajectories of the driving tips were investigated. A prototype of the standing wave type linear ultrasonic motor was fabricated and its impedancefrequency characteristic was measured. The measurement results verified the analytical results.