基于直线型超声电机的两自由度精密定位平台

搭建了一种新型两自由度精密定位平台，主要由直线型超声电机、直线导轨、工作台三部分组成。采用了直线型超声电机，利用非统一截面杆在正交方向上的两个四阶弯振模态作为工作模态，其最高速度为190mm／s，最大推力为19N。该平台具有响应速度快，无后冲，高精度，断电自锁和工作行程大的特点。在位置检测装置具有1μm分辨率的情况下，其闭环最高定位精度小于2μm，且开环分辨率可达到1μm。

TWO DOF POSITIONING STAGE USING LINEAR ULTRASONIC MOTORS

A two degrees of freedom (DOF) positioning stage using novel linear ultrasonic motors is presented.The stage mainly consists of two linear ultrasonic motors,linear guides and tables.It can realize the long stroke and reversible controlled motion in two directions.The wheel-shape linear ultrasonic motor applied in the stage utilizes two fourth-bending modes of non-uniform beam in orthogonal directions.Quick response,no backlash,high resolution,power-off self-braking,and long stroke are the attractive characteristics of the linear positioning stage.Experimental results show that x and y-direction tables can reach the destination without overshoot and the error is less than 2 μm by using two linear encoders with a resolution of 1 μm.In the open-loop mode,the positioning stage achieves 1 μm resolution at 0.25 ms driving time.