Design And Implementation Of Single Coil Vibrating Wire Sensor Data Acquisition System

In the field of engineering,sensor monitoring system instead of manual monitoring has been widely used in these years.Vibrating wire sensors with its advantages of simple structure,strong and durable,the output frequency signal anti-jamming is widely used in water conservancy,transportation,mining,petroleum,etc.in the field of geotechnical engineering since the beginning of twentieth century.But in actual projects its internal string is hard to exciting occasionally,and its accuracy is not satisfied.So that the vibrating wire sensor can't be used in some high requirement So the research of the data acquisition system of vibrating wire sensor is one of the methods to improve its reliability.In this paper,single coil vibrating wire sensors are taken as the object of study.In order to solve the problem that it is difficult to oscillate,a driving circuit with strong drive capability is designed on the hardware.An improved adaptive sweep frequency method is designed to improve the reliability of the system.Because of the different manufacturing process,the vibration signals of different types of vibrating wire sensors have differences in the amplitude of the output signal and the excitation of the steel string.In this paper,the hardware design of the circuit are picked up by vibration of the vibrating wire sensor,the software design of the improved adaptive frequency sweep method makes the system can be applied to different types of vibrating sensor,expanding system for vibrating wire sensors of different types of compatibility.In this paper the vibration pickup circuit before the sensor output signal amplifier uses a differential low pass filter,suppress the RF interference may exist in the system,the output signal of the sensor first amplified band pass filter is used to eliminate the possible high frequency or low frequency interference signals,under the same conditions the accuracy of sensor next,improve the measurement accuracy of the system.To measure the frequency of output signal of the sensor,this paper use the pick-up circuit to the corresponding small signal processing the rectangular wave first,and then use the STM32 internal timer capture function of the frequency measurement,relative to the external counter frequency measurement method simplifies the hardware circuit of the system.Finally,this paper uses Multisim and other simulation software to simulate the hardware circuit of the measurement part to ensure the accuracy and reliability of the system circuit design.At the same time,the data acquisition system is used to measure the existing equipment in the laboratory,and the results are analyzed to verify the performance of the system.