Design And Research Of Signal Acquisition System For Vibrating Wire Sensor

Vibrating wire sensors play an important role in monitoring the safety and reliability of engineering systems,and thus the vibrating wire acquisition systems used in conjunction with them are more widely used.However,the current Vibrating Wire Acquisition System is expensive and single-function,the traditional excitation strategy is less efficient in acquiring sensor frequency data,and the method of evaluating the Vibrating Wire Acquisition System is limited.Also,when measuring the strain parameters,the measurement personnel ignore the effect of temperature or use the reference value in calculating the temperature compensation coefficient.Therefore,it will be of great theoretical and practical significance to conduct temperature compensation experiments based on the design of a low-cost,fast and accurate,and well-evaluated net-linked Vibrating Wire signal acquisition system to revise the temperature compensation coefficients and realize the accurate calculation of strain values.In this paper,the key technologies such as the principle of the vibrating wire sensor,the principle of the excitation method,the design of system software and hardware,the evaluation of measurement uncertainty by improved interval scanning method,the evaluation of Measurement uncertainty of GUM and MCM Methods,the sensor calibration,temperature compensation coefficient correction by temperature compensation experiment are investigated.The signal acquisition system of the vibrating wire sensor is designed and evaluated for uncertainty.And the temperature compensation coefficient is revised to make the strain calculation of the measured object more suitable for engineering practice,which realizes the fast,accurate and intelligent engineering data monitoring and further ensures the safety of the infrastructure engineering.In the process of researching and designing the signal acquisition system of vibrating wire sensor,firstly,the hardware circuit of the signal acquisition system,including the excitation pickup module,the main control module,the communication module,the power supply module and the temperature acquisition circuit with temperature compensation are designed.And Multisim simulation of the excitation pickup module is also conducted to ensure the correctness of the circuit design.Next,the software for various part of the signal acquisition system is designed,and an improved interval sweep method based on the low-voltage sweep method is proposed to improve the measurement speed and the accuracy of the sensor.Then,the system debugging verification of the signal acquisition system is completed and the test results are analyzed and verified.Finally,for the vibrating wire sensor,the GUM method and the MCM method is applied to evaluate the uncertainty of the frequency and temperature data for the signal acquisition system designed.The evaluation results are compared,among which the MCM method solves the deficiency of the traditional "static instead of dynamic" measurement uncertainty evaluation method.The calibration parameters of the sensor are obtain by calibration experiments,and temperature compensation experiments are conducted to revise the temperature compensation coefficients.The study of this system not only improves the excitation strategy method in theory and enriches the measurement uncertainty assessment method in the dynamic measurement process of the acquisition system,but also improves the accuracy of the calculated strain value in practice and optimizes the vibrating wire sensor acquisition system,which has certain theoretical and practical significance.