| A novel annular sector curvilinear ultrasonic motor with composite in-plane bi-mode is presented and optimally designed by combining genetic algorithm and finite element method together in this paper. The optimization structure of the vibrator is determined. According to the optimization results, the sample motor is fabricated and tested. The results show that the consistency of the resonance frequencies of the vibrator by optimization design is satisfied and the motor can work well driven by only one single frequency power supply. |