Signal Sampling And System Construction In Seismic Wave Detection Of Digital Grating

With the development of the global economy as well as the energy crisis, improvingthe technology of oil and gas exploration, increasing oil reserves has become a toppriority in many countries around the world. As the primary part of oil and gasexploration, the development level of seismic geophone has become an important markof the measurement ability of oil and gas exploration. and the grating seismic geophonewith high detection performance and strong electromagnetic compatible performanceshows its great development prospects. This paper aimed at studying a kind of digitalgrating geophone and its signal sampling and error correction.In order to meet the modern high precision and large dynamic range of the seismicwave detection, This paper designed a kind of vibration sensor based on grating moirefringe measurement principle, avoiding the signal distortion of traditionalmagnetoelectric detector caused by nonlinear magnetic circuit. The detector structurecomposed of shell, grating measurement system and "spring-quality" vibration system.Considering the spring leaf’s nonlinearity has an effect on the natural frequency and theoutput signal of the system, analyzed from the theoretical point of view detector springleaf on the influence of the vibration system, and the finite element simulation of leafspring, discussing the relationship between sping leaf and the natural frequency. At thesame time calibration device was designed for calibration detector.A data acquisition circuit based on MP426data collection card is used for signalsampling,with the analysis of the characteristics of grating signal and the real seismicwave detection requirements, the article puts forward the idea of a large capacity gratingdata acquisition system. The experiment part, through the method of vibration tablesimulation of artificial earthquake,collecting the grating data within the scope of100Hz,Through the different frequency grating data Lissajous circle’s analysis,and analyzes thereasons of possible error. At the same time, in view of the grating signal error producedby itself, proposing a correction method based on single variable recursive errorseparation.