Research On Planar Cross Array System Based On Magnetic Gradient Tensor

Magnetic anomaly detection technology can calculate the position information between the magnetic target and the probe,and obtain the magnetic field information of the magnetic target,which is widely used in the military field.In recent decades,the material of magnetic sensor technology and processing technology has achieved great development,the level of magnetic detection also in unceasing enhancement,the application of computer technology also makes the magnetic anomaly detection technology development to a higher level,the two promote each other,to jointly promote magnetic anomaly detection technology constantly breakthroughs in terms of theoretical research and engineering application.This paper studies and designs a measurement array system of cross array,which is devoted to the research of magnetic target positioning based on magnetic dipole model,and USES magnetic gradient tensor information to reduce the influence of target attitude and geomagnetic field.The main research work of this paper is as follows:Based on the magnetic dipole model and the magnetic gradient tensor,a single point inversion positioning algorithm suitable for the system is studied and derived,and a measurement array system is designed according to this algorithm.The research of array system includes:flux gate detector type selection,data acquisition module design,array system design and construction,upper computer software design.Hardware equipment includes three-axis fluxgate sensor,data acquisition module based on AD7799 chip,CAN bus transmission line,upper computer including software system,etc.The whole power supply is 24V,and the magnetic gradient tensor,magnetic field size and position information of the magnetic target can be measured by synchronous acquisition command.After receiving the acquisition instruction from the upper computer software,the data acquisition module starts to collect the voltage signal generated by the magnetic sensor,conduct synchronous real-time acquisition and high-speed AD conversion of the signal,communicate with the upper computer through CAN bus mode,and finally display it in the form of two-dimensional waveform after processing by the upper computer software.The upper computer software is written in Python and Matlab languages,which can realize real-time display of collected magnetic detection data in the form of waveform,and can save existing data.The magnetic detection algorithm realized through programming can locate the location information of the measured target.Verify the feasibility of the algorithm and system through experiments,design experiments to enable the array system to measure the position information of magnetic objects,and display the magnetic field data and total magnetic field data of each axis of XYZ in real time on the upper computer,and calculate the path of magnetic objects based on the magnetic field data.