A standing-wave-type stepping ultrasonic motor using the alternative operation of two bending vibration modes on the stator has no accumulative errors without the feedback. 摘要利用環(huán)形定子的兩個(gè)彎振模態(tài)交替工作的原理設計的一種駐波型步進(jìn)式超聲電機具有開(kāi)環(huán)控制下無(wú)累積誤差的特性。