Development Of Platform Vibration Monitoring Device Based On Piezoelectric Sensor

As an important condition monitoring technology,vibration monitoring technology is based on the vibration state parameters during the operation of the equipment,combined with the means of fault and algorithm diagnosis to evaluate the health status of the equipment.Optical platforms are widely used in optical experimental testing,acting on experimental platforms that carry optical instruments and isolate environmental vibrations.The natural frequency of the optical platform,the transmission rate and the vibration isolation performance of the vibration isolation frequency range directly affect the accuracy and reliability of the optical platform.Therefore,monitoring the vibration of the optical vibration isolation platform is of great significance.In this paper,PVDF piezoelectric film sensor is used as the sensitive unit of the device to develop a device for vibration monitoring of optical platform.The purpose of this paper is to amplify the weak charge signal generated by the vibration of the optical platform,and input the processed signal into the microprocessor for A/D conversion.The frequency measurement range is judged by the characteristics,and the function relationship between the voltage and the vibration intensity is fitted,and the detected voltage peak is estimated by the function relationship to calculate the dynamic stress received by the sensitive unit,thereby judging the influence of the environment on the vibration intensity generated by the optical platform.In this paper,PVDF piezoelectric film sensor is used as the sensitive unit.PVDF piezoelectric film has the characteristics of good low frequency response,light weight,high sensitivity and high stability.In this thesis,the signal conditioning circuit is designed,including a charge voltage conversion module,a voltage amplification module,a low-pass filter module,a power frequency notch module and an overload indication module.The digital signal acquisition module uses the A/D conversion function of the STM32F103VET6 microprocessor to design a minimum system.In this thesis,each module is packaged and assembled,and the optical platform vibration monitoring device is built.The measurement and calculation are carried out by the standard vibration measurement system,and various performance parameters such as the frequency measurement range and sensitivity of the device are given.