基于超声驻波的径向悬浮移动系统研究

Study on the Radial Levitation System Based on Ultrasonic Standing Wave

常用的声悬浮系统是采用一维单轴式超声悬浮装置,利用驻波特性仅能使少量小颗粒悬浮在声压节点处。为改善实验效果,该文在传统悬浮装置的基础上作了改进,设计了一种径向悬浮移动系统,采用相控阵探头板作为发射端和反射端,结合高频时钟驱动的现场可编程门阵列(FPGA)作延时控制,改变发射波束与反射波束间的相位差,使小颗粒可呈阵列式悬浮移动。系统中所设计的驱动电路是采用金属氧化物半导体场效应晶体管(MOS)结合变压器的电压驱动方式,无需考虑输入端信号的电流大小及MOS管无需接高上拉电压。通过对系统的硬件测试及仿真,结果表明,该文方法比传统方法能稳定悬浮多个小颗粒,且能使悬浮小颗粒平滑移动,具有较好悬浮稳定性和可靠性。

The conventional acoustic levitation systems commonly use one-dimensional,single axis ultrasonic levitation device,only a small amount of particles can be levitated at the acoustic pressure nodes by using the standing wave features.In order to enhance the experimental effect,a radial levitation mobile system has been designed based on the improvements of the conventional levitation system in this work.The small particles can be moved in an array by using the plane phased array probes as the transmitter and reflector and using the high frequency clock driving FPGA as the time-delayed control to change the phase difference between the emission beam and reflected beam.The designed driving circuit in the system uses the voltage drive method with MOS tube and transformer,so that there is no need to account on the current size of input terminal and no need to pick up the high voltage of MOS tube.The hardware testing and simulation results show that the proposed method can levitate more particles stably than the conventional method and make the particles move smoothly with better levitation stability and reliability.