Design Of Ultrasonic Test Transceiver System For Dynamic And Variable Structural Components

In the field of nondestructive testing,ultrasonic testing,as an important nondestructive testing method,is widely used in aviation,aerospace,military,industry and other fields.In engineering,the dynamic changes of the morphology and structure component is often met in ultrasonic testing of engineering problems,for example,in the process of solid rocket motor combustion materials ultrasonic attenuation is strong,launch to pursue to maximize efficiency,and in the process of burning surface move back monitoring,received signal dynamic range is larger,the need for dynamic range compression.The ultrasonic dynamic and variable structural component testing puts forward new requirements for testing instruments.Mainly reflected in the frequency and energy matching of the transducer;Adaptive amplification and filtering of received signals.In addition,for some special environments,remote detection is needed.At present,there is no ultrasonic testing instrument to meet the requirements of the above engineering testing.According to the characteristics of dynamic variable structure components and testing requirements,this paper studies the dynamic variable structure send and receive ultrasonic testing system design and implementation of the method,with large dynamic variable structure composite component testing as the background,based on the modular design principle,which are combined to design the working frequency range of 20 k Hz～2MHz four-channel ultrasonic transmitting and receiving system.In order to meet the requirements of multi-station dynamic and variable structural component detection and ultrasonic imaging,the designed system has the synchronous sending and receiving functions of single-send,single-send and multi-receive and multi-receive.Launch module using bipolar pulse form,peak-peak value up to 1000 V,output voltage is the voltage adjustable,the polarity of the excitation signal,cycle number,repetition frequency,pulse width control,transducer frequency adaptive matching function,can realize the transducer working frequency automatic tracking and adaptive regulation of excitation pulse width,in order to achieve the maximum output of ultrasound transmission power.In the receiving module,programmedlinear amplifier,large dynamic logarithmic amplifier and adaptive filter based on state variable filter are designed to achieve linear gain adjustment and large dynamic range logarithmic amplification of ultrasonic signals,ensuring the effective acquisition of large dynamic range ultrasonic signals.Filter parameters can be adjusted automatically according to the transducer working frequency measured by the transmitting module.In order to meet the requirements of remote detection,a high-speed acquisition and transmission module based on Zynq is designed in this paper.Zynq is used as the main control chip,and software and hardware are co-developed to realize the four-channel parallel acquisition and transmission,with a sampling rate of 12.5MSPS and a resolution of 14 bits.Finally,with solid rocket engine propellant burning surface detection as the application background,the thickness change simulation test and performance evaluation of the transceiver system designed in this paper are carried out.The experimental results show that the system can be applied to the requirements of dynamic and variable structure ultrasonic detection.