Research And Design Of Pressure Measurement System Based On Vibrating Wire Sensor

In the security monitoring of large civil engineering, As an important parameter, the methods of pressure measurement have always been paid great attention. It has an important significance for protecting their health and reducing the accident rate, through monitoring the pressure of various structures on real-time. Because of the advantages of vibrating wire sensors such as output signal stability, easy to detect and so on, a pressure measurement system was designed which has a simple hardware structure with good reliability and high accuracy by vibrating wire sensor in this paper.Firstly, the paper compare with common used pressure sensors, explain the basis of selecting the vibrating wire sensor, analyze its structure and working principle, summarize the foremost factors that influence the measuring accuracy of vibrating wire sensors, propose some corresponding improved methods.The exciting methods of vibrating wire sensor are studied and optimized mainly, a new exciting method based on feedback is used and a rational signal processing circuit is designed in the paper. The system is a distributed data acquisition system, which consists of data acquisition system and sensors. Every data acquisition system could mount many sensors and achieve multi-point detecting. Choose system on a chip C8051F340 that real work independently as MCU, design a vibrating wire sensor excitation circuit, a frequency measurement circuit, a display circuit,serial communication interface circuits and so on. At the same time, also design complete lower computer software that enable the hardware to achieve its normal function. The software is programmed in C language that has clear structure and is easy to transplant, maintain and upgrade with modular programming idea. At last, anti-jamming designs of hardware and software is made in the system to ensure it works properly for interference problems that exist in the electronic circuit system.After more than a month debugging, all parts of this system work properly. The experiment results indicate that the system has very good measurement accuracy and a stable and reliable performance. The characteristic of this system are small cubage, low cost, general interface and used by almost vibrating wire sensors, which has some value in engineering.