Research On Magnetic Signal Simulation Technology In The Simulation Environment Of Aerial Magnetic Exploration

Magnetic anomaly detection system measures the earth's magnetic field with the magnetometer sensor mounted on the aircraft.Compared with the ground magnetic measurement method,it involves more complex algorithms like signal processing,interference compensation and so on.The signal simulation of aeromagnetic exploration system is an important support for the research of aeromagnetic exploration technology.The characteristics of low cost and short period are conducive to the fast verification and iteration of algorithm research.The key point of signal simulation of aeromagnetic exploration system is to reappear the dynamic changing environment magnetic field and interference magnetic field under real flight conditions.Both of these two kinds of magnetic fields are related to the aircraft's trajectory and attitude.This paper starts with the flight simulation of the aircraft,the motion parameters of the aircraft are obtained through the hardware in loop simulation of the real flight control equipment,and then the magnetic sensor signals are simulated by the high-precision geomagnetic model and the aircraft platform interference model.The main innovations in this paper are as follows:Firstly,the flight trajectory and attitude data are generated by hardware in loop simulation.In order to simulate the motion parameters closer to the real maneuver,a set of hardware in loop platform is built based on the X-Plane simulation aircraft,QGround Control ground station,FUTABA T18 SZ remote control,airborne track planning platform and Pixhack flight control,and the effectiveness of the simulation results of the aircraft motion parameters is verified by the attitude coupling and drop height during the maneuver;Secondly,the simulation of the environmental magnetic field signal of the aeromagnetic exploration flight platform is realized.The simulation of the external magnetic field components is carried out by means of EMM,which describes the magnetic field with higher accuracy,and DC elimination of the measured daily variation signal.The validity of the simulation results of the environmental magnetic field components of the aeromagnetic exploration flight platform is verified by the simulation accuracy,the magnetic field intensity range and the spectrum range;Thirdly,the simulation of the interference magnetic field signal generated by the aeromagnetic exploration flight platform is realized.Based on the physical principle of the interference components of the platform,the mathematical model of each interference source is derived,and the intensity of each interference source is controlled by the way of distribution of points.Then the magnetic field components generated by the aeromagnetic exploration flight platform are verified by the simulation accuracy,the magnetic field intensity range and the spectrum range;Finally,a magnetic compensation test device based on the simulation platform is developed.The device receives the simulated sensor data through the serial port,compensates and filters the received total field data,and verifies the effectiveness of the simulation interference total field signal by calculating the corresponding compensation index.