The Development And Application Of High Speed And High Sampling Rate Wireless Acoustic Detection System Based On WIFI

In the modern engineering, large-scale engineering structures such as Bridges, DAMS,tunnels and other defects or cracks, will cause great influence to the engineering quality and safety. Representative method in engineering structure and its quality detection is the sound wave test. The traditional acoustic detection is the use of sound wave detector for data acquisition, whose detector are mostly using a serial port cable transmission. The disadvantage such as low data transmission rate, less of real-time, low sampling rate, together with bulky and heavy instrument, did a lot of limitations of engineering quality inspection which needs much measuring point.With the rise of the wireless communication technology,WIFI has been widely used in industry and people’s life, with its high speed and high reliability.In this paper, aiming at the problems existing acoustic detection system, combined with WIFI wireless communication technology, we developed a high speed high sampling rate wireless acoustic detection system, completed the system hardware and software design,tested the performance of the system, and verified the feasibility of the system in practical engineering application. Concrete research content is as follows:(1) Designed the overall structure of the system, analyses the key technology used in the system according to the actual application requirements and performance required index.Devoloped the STM32 MCU as the core of data acquisition circuit, and the WIFI wierless module as the core of the wireless communication circuit. Implemented the acoustic detection system of high speed which is up to 150 Mbps and high sampling rate which is up to 1MHz by both software and hardware designs. The software program of data acquisition and processing,the realization of the acoustic emission and pulse received by the synchronous control, and adopts the wireless transmission of data in the form of data frame transmission effectively guarantee the reliability of the data.(2) According to the practical application of acoustic detection system operation requirements, developed a Windows application which used LabVIEW platform. Designed data acquisition software and signal analysis software. Communicated the application software and acoustic detection system with the help of TCP/IP communications protocol.Use of signal processing and analysis of the LabVIEW built-in unit to write the signal analysis software for data analysis and evaluation about the quality of the test object.(3) Tested the performance of system, applied it to practical engineering. Tested the system with an obstacle in the environment of wireless communication distance and open environment, as well as the system of anti-interference ability and packet loss rate of the system. The results showed that, wireless communication distance is up to 1000 meters in the open environment, wireless communication distance is 80 meters in the obstacles environment while the actual distance of wireless communication is depending on application environment; system for wireless transmission of large amounts of data through a long time,the packet loss rate is zero, and the system is stable and strong anti-interference ability.Through testing on outdoor NDT quality model and analyzing the collected data, contrasted waveform difference with defects and without defects, judging the quality of the test object,the reliability of the wireless acoustic detection system and stability.In this paper, the author studied on system closely the actual application requirements,separated the acoustic detection system with the user control, greatly increased the flexibilityand reliability of the engineering quality detection, which has certain practical significance and broad application prospects.