脉冲超声换能器声场测试系统的设计*

脉冲超声换能器是超声检测的关键部件,为了获取其声场特性参数,文中基于小球反射法原理,采用虚拟仪器技术和单片机技术设计了声场测试系统。系统的程控交互界面采用了美国国家仪器公司研制开发的图形化编程软件LabVIEW来设计,在程控交互界面程序中通过调用动态链接库DLL来对系统核心硬件超声发射接收卡进行数据通信及对卡功能进行设置,同时系统上位机通过RS232串口与下位机单片机通讯,实现对三轴扫查平台的多种扫查方式控制。该系统可实时显示脉冲换能器声压分布图像,并可通过对声压分布数据实现对换能器近场长度及扩散角等参数的测量。

Design of sound field testing system of pulsed ultrasonic transducer

Pulse ultrasonic transducer is the key component of ultrasonic detection. In order to obtain its acoustic field characteristic parameters, the sound field measurement system is designed based on the principle of small ball reflection method and the technology of virtual instrument and single chip microcomputer. The program-controlled interactive interface of the system is designed with the graphical programming software LabVIEW developed by the National instrument Company of the United States. In the program-controlled interactive interface program, the data communication and the function of the card are set up by calling the dynamic link library (DLL). At the same time, the host computer of the system communicates with the MCU through the RS232 serial port. Realize the three-axis scanning platform of a variety of scanning mode control. The system can display the image of the acoustic pressure distribution of the pulse transducer in real time and measure the parameters of the transducer such as the near field length and the diffusion angle by the sound pressure distribution data.