Study On Soft Compensation Of Aeromagnetic Full Tensor Data

The magnetic response of the machine and its magnetic member caused by the changing of the aircraft’s attitude angle is called the maneuvering noise of the aircraft,which needs to be estimated and eliminated to ensure that the value of the magnetic field is measured with high precision,and this is also known as magnetic compensation aircraft process.In 1950,W.E.Tolley and J.D.Lawson firstly proposed the establishment of compensation equation method with compensation coefficients to solve this problem.Leliak,in 1961,proposed the suggestions of evaluation and improvements for the compensation method of Tolley and Lawson.As the main theoretical basis of maneuvering aircraft noise compensation,this method is used into the production practice widely.Firstly,we revisit the basical theory of magnetic compensation method and organize its theoretical basis,derivational process and applicational conditions.According to this,we establish corresponding theoretical model under this laboratory conditions to simulate the maneuvering attitude of the aircraft and the external environment.The next step is to translate the physical model into corresponding mathematical problem and select the optimal solution to obtain appropriate compensation coefficients,stored in database in real-time compensation to be invoked under the same conditions to solve the motorized interference noise in the actual flight of aircraft.For example,we use the rotation of sphere and cuboid to simulate the aircraft flight attitude,combine several magnetic dipole and forward the interference field of them.Then build the compensation equation of total field using the simulation attitude and get the compensation coefficients and interference field in the process of simulating actual flight.The downside of the compensation theory proposed by Leliak is that it is only applied to the total field but not to the vectors and gradient compensation.Here,based on this theory,we derive the compensation method of magnetic vector and gradient according to the conversion relation among the total magnetic field,the magnetic field vector and the gradient.Under laboratory conditions,accomplish the building of compensation models,calculating of compensation coefficients and compensation of the experimental data which simulate the actual flight.Give a comparison of results before and after compensation and analyze the anticipated problems of the future and its applied range.In actual flight data,use this method to compensate the measured total field,three-component fluxgate and deduced full tensors magnetic gradiometry and give the error analysis and feasibility evaluation modeling on the total field compensation.In this paper,we achieve the data computing and data processing according to the Matlab software programming,including the least squares method to solve the compensation equations,high-pass filter design and filtering process,calculating the interference field of actual flight,evaluating compensation results and verifying the effectiveness of the method proposed in this paper.