Development Of Laser Ultrasound Analog Driving Source Based On USB2.0

In the field of ultrasonic testing, comparing with the traditional methods laser ultrasound is an advanced technology, which is non-contact, long distance and broad frequency bandwidth. So there are broad application prospects of the laser ultrasonic testing. The main content of this paper is to design a driving source for laser ultrasound testing to analog the laser source.In the laser ultrasonic testing system research experiment, as a replacer of high-power laser, it should not only generate continuous signals, but also generate intermittent signals, and even user-defined signals. And the frequency and amplitude of signals could be adjusted with high accuracy and wide range too. Most electrical signal sources now adopt the hardware circuit design proposal and can only generate the regular and continuous signals, so they don't meet the requirements of laser ultrasonic testing system research experiment. A new ultrasound analog driving source is developed which combines virtual instrument technology and USB technology. This design adopts an USB2.0 bus with high-speed, stable data transmission characteristics to connect the computer on which the virtual instrument application and peripheral circuit. The design makes full use of the advantages of both technologies. The driving source developed according to the new design can generate user-defined signals, and the frequency and amplitude of signals can be adjusted neatly. So the driving source meets the requirements of laser ultrasonic testing system experiment.Based on the presentation of the design, this thesis puts emphasis on the realization of design proposal. On the hardware system design, this thesis focuses on the composing of the hardware, the design and production of USB peripheral equipment circuit function modules. On the software system design, this thesis introduces the program design, compilation and debugging of USB firmware, USB driver and client application.The testing of system hardware and software designed in this thesis shows that the client application can control the USB peripheral device to generate a variety of user-defined drive signals, and the frequency and amplitude of signals can be adjusted too. Those performances of the design achieved the anticipative target. So the ultrasound analog driving source which adopts virtual instrument technology and USB technology is suitable to the application in ultrasonic testing system experiment.