Design And Implementation Of Full Tensor Gravity Gradiometer Simulation System

As an instrument for obtaining full tensor gravity gradient information,full tensor gravity gradiometer plays an important role in resource exploration,navigation guidance,space exploration and other fields.In this paper,the rotating accelerometer gravity gradiometer is studied.The main contents and achievements are as follows:From the physical meaning of gravity gradient,the measuring formula of gravity gradient instrument of rotating accelerometer is deduced,and the construction scheme of full tensor gravity gradient instrument is analyzed.The gradient signal model and simulation model of full tensor gravity gradient instrument are established,and the output error of gradient signal is analyzed from the perspectives of matching error and installation error of accelerometers.The simulation system of the tensor gravity gradiometer is built.According to the signal processing flow of this system,the signal generation module,the signal transmission module,the signal conditioning module and the signal demodulation module are designed.The theoretical model is used to simulate the data of the three-disk accelerometer of the full tensor gravity gradiometer.The theoretical data are analyzed according to the installation error,scale factor error and quadratic error of the accelerometer,and the effects of different error items on the combined output signal of the three-disk accelerometer are compared.The signal sending module sends the accelerometer signal to the signal conditioning module for processing.At the same time,the incremental PID algorithm is used to adjust the amplitude and the phase angle of the accelerometer combination signal.Signal demodulation module receives the combined signal of accelerometer and demodulates the feedback of the gradient signal and the amplitude and the phase angle of the combined signal of accelerometer in real time.After calibrating the initial parameters and testing the performance of the simulation system,a series of full tensor gravity gradient measurement experiments were carried out.The three-disk accelerometer data including installation error,scale factor error and quadratic error are loaded into the system to carry out experiments,and the full tensor gravity gradient signal output by the system is analyzed.The experimental results are in good agreement with the theoretical values and the errors are controlled within 1E.