CN109613458B

CN109613458B - Spacecraft magnetic anomaly positioning method

Info

Publication number: CN109613458B
Application number: CN201910031891.XA
Authority: CN
Inventors: 徐超群; 易忠; 孟立飞; 王斌; 刘超波; 黄魁
Original assignee: Beijing Institute of Spacecraft Environment Engineering
Current assignee: Beijing Institute of Spacecraft Environment Engineering
Priority date: 2019-01-14
Filing date: 2019-01-14
Publication date: 2020-12-01
Anticipated expiration: 2039-01-14
Also published as: CN109613458A

Abstract

The invention discloses a method for positioning magnetic anomaly of a spacecraft, which comprises the following steps: setting a spacecraft measurement model space, establishing a coordinate system, carrying out gridding processing on the model space, establishing an equation by using the vertical gradient tensor combination of four adjacent measurement points through measuring the magnetic abnormal data on a certain surface of the space model, calculating the position of an abnormal point, then obtaining a plurality of position points, namely a grid where a dense point is located, namely the abnormal position, and then calculating the magnetic abnormal magnetic moment. The method is simple and easy to implement, and the calculation result is reliable.

Description

Spacecraft magnetic anomaly positioning method

Technical Field

The invention belongs to the technical field of magnetic measurement and calculation of spacecrafts, and particularly relates to magnetic anomaly measurement and calculation of spacecrafts and objects.

Background

The magnetic environment of the earth and the interstellar space is one of important environments influencing the operation of the spacecraft, the influence degree of the magnetic environment is related to the magnetic size of the spacecraft, and in order to meet various performance requirements, the spacecraft needs to use a certain amount of magnetic materials and has a certain magnetic field. Secondly, the change of the external magnetic field can cause the change of the magnetic characteristic parameters of the spacecraft, particularly the satellite for magnetic field research needs to limit the magnetic field of the satellite, particularly the magnetic field intensity and stability of the installation part of the magnetic field monitor, so that the reliability of detection data can be ensured. In addition, for a spacecraft which utilizes a magnetic torquer to perform attitude control and orbit positioning, the on-orbit magnetic state needs to be fully known so as to ensure the effectiveness of control and the accuracy of measurement. The orbit and the attitude of the spacecraft can be changed due to the accumulation of the interaction of the earth magnetic field and the magnetic moment of the spacecraft when the spacecraft runs on orbit for a long time. Therefore, the assembled spacecraft must be subjected to measurement, compensation and evaluation of a strict ground magnetic test, so that the magnetic characteristics of the spacecraft can be accurately controlled, and even when the spacecraft has magnetic anomaly, diagnosis and remediation can be timely carried out, which is vital to reducing or avoiding the occurrence of faults or failures of the spacecraft and prolonging the service life of the spacecraft.

At present, a better method for calculating the magnetic anomaly position and information does not exist, the magnetic anomaly position is mainly solved by using an Euler equation and a magnetic field full tensor, and the method needs more data and is easy to cause solution divergence.

The invention provides a spacecraft magnetic anomaly positioning method, which is used for positioning and calculating the magnetic anomaly inside a spacecraft by utilizing the magnetic anomaly data outside the spacecraft and combining the magnetic tensor gradient vertical component.

Disclosure of Invention

The invention aims to provide a method for positioning magnetic anomaly of a spacecraft. The method comprises the steps of setting a spacecraft measurement model space, then carrying out gridding processing on the model space, establishing an equation by using the vertical gradient tensor combination of four adjacent measurement points through measuring magnetic anomaly data on one surface of the space model, calculating the position of an abnormal point, and then calculating the size of magnetic abnormal magnetic moment. The method provides valuable reference information for the design, manufacture and magnetic compensation of the spacecraft, and also provides evaluation basis for the magnetic anomaly of the spacecraft before and after the on-orbit operation.

In order to solve the problems, the technical scheme adopted by the invention is as follows:

the spacecraft magnetic anomaly positioning method comprises the following steps: establishing a spacecraft measurement model space and establishing a coordinate system; carrying out gridding processing on the measurement model space; measuring the magnetic field and the vertical gradient tensor of a grid point of a certain plane in the space of the spacecraft model; and establishing an equation of magnetic field vertical gradient tensor component information at each grid point: establishing an equation set by using four adjacent grid points, solving the magnetic anomaly position (x, y, z) information until all the grid points are covered,

the equation is (x-x)₀)B_zz+(y-y₀)B_yz+(z-z₀)B_xz＝-3(B_z-b_z) (2)

Wherein Bz is the vertical component of the magnetic field at the measuring point, and Bz is the backgroundVertical component of magnetic field at measuring point, x₀,y₀,z₀Is the coordinate of the measuring point, the magnetic abnormal position information x, y, z;

the system of equations is:

and solving all solutions, wherein (x, y, z) obtained by solving the equation group falls into the most grids, namely the area where the magnetic anomaly is located, and then calculating the magnetic moment of the magnetic anomaly by using a magnetic field formula according to the position information.

Preferably, an easily measurable space is established, which contains the spacecraft, and a coordinate system is established in the space.

Preferably, the model space is set to be square, and the square is gridded, so that the model space is composed of a plurality of small blocks, and the measurement and solution are convenient.

Preferably, the magnetic anomaly data of the surface of the measurement space model is a magnetic field and a magnetic field vertical tensor of a grid node of a certain plane of the measurement space model.

The method has the advantages of simple and easy realization, small calculated amount, high precision, and solving of the abnormal positioning image, which is specifically shown in the following steps:

1. the spacecraft measurement model space is set, so that the positioning space is quantized, and meanwhile, the data measurement efficiency and precision are improved through gridding treatment;

2. an equation is established by utilizing the vertical single component of the magnetic field gradient tensor, so that the calculated amount is reduced, the introduced error caused by using other magnetic field tensor components is reduced, and the convergence and the accuracy of the understanding are improved;

3. the grid where the dense solution is located is used as the position solution of the magnetic anomaly, the narrow-sense solution with the output result as one point in the past is broken through, the anomaly positioning result is optimized, and the anomaly area is depicted more vividly.

Drawings

Fig. 1 is a flowchart of a spacecraft magnetic anomaly positioning method of the present invention.

Fig. 2 is a schematic diagram of measurement space gridding in the spacecraft magnetic anomaly positioning method of the invention.

Fig. 3 is a point diagram of equation sets in the spacecraft magnetic anomaly positioning method of the present invention, wherein an equation can be established for each grid point, and an equation set is established for every four points, so as to obtain a solution about magnetic anomaly location points.

Fig. 4 is a grid schematic diagram of a dense solution of magnetic anomaly coordinates in the spacecraft magnetic anomaly positioning method of the present invention. Each equation set can be solved to obtain a solution, the position coordinates of the solution are different, all points of a detection surface have a plurality of solutions, and a grid where a dense place is located is an abnormal area.

Detailed Description

The spacecraft magnetic anomaly localization method of the present invention is described below with reference to the attached drawings, but the description is merely exemplary and is not intended to impose any limitation on the scope of the invention.

Referring to fig. 1, fig. 1 shows a flow chart of the spacecraft magnetic anomaly positioning method of the present invention. The method for positioning the magnetic anomaly of the spacecraft comprises the following steps,

the spacecraft is placed in a magnetic shielding room, a measuring space, which is generally square, is established, the space comprises the whole spacecraft, and a coordinate system is established in the space.

The measurement space is divided into several grids so that each side of the measurement space consists of many squares, see for example fig. 2, where the higher the accuracy requirement the smaller the divided grid and vice versa.

Measuring three-direction magnetic induction B of each grid point position by using a magnetometer_x,B_y,B_zThe vertical gradient tensors Bzz, Byz, Bxz are calculated by the difference method of equation (1).

Each measuring point establishes an equation of magnetic field vertical component information:

(x-x₀)B_zz+(y-y₀)B_yz+(z-z₀)B_xz＝-3(B_z-b_z) (2)

wherein Bz is the vertical component of the magnetic field at the measuring point, Bz is the vertical component of the background magnetic field at the measuring point, x₀,y₀,z₀Is the coordinate of the measuring point, and the position information x, y and z of the magnetic anomaly.

An equation set (3) is established for every four measurement points, and the magnetic anomaly position (x, y, z) information is solved, and the established equation set is up until all points are covered, as shown in FIG. 3.

Solving the equation sets, wherein each equation set can obtain a solution, each solution is corresponding to a measurement space, a grid space region of dense solutions is searched for as an output result, as shown in fig. 4, a small black point is the solution of each equation set, and a grid is a final solution, namely a magnetic anomaly region;

and fifthly, substituting the position information into an equation (4), solving the size of the magnetic anomaly, and finally obtaining all information of the magnetic anomaly.

Although particular embodiments of the invention have been described and illustrated in detail, it should be understood that various equivalent changes and modifications could be made to the above-described embodiments in accordance with the spirit of the invention, and the resulting functional effects would still fall within the scope of the invention, without departing from the spirit of the description and the accompanying drawings.

Claims

1. The spacecraft magnetic anomaly positioning method comprises the following steps: establishing a spacecraft measurement model space, establishing a coordinate system, establishing the spacecraft measurement model space means establishing a space which is easy to measure and contains the spacecraft, establishing the coordinate system in the space, setting the spacecraft measurement model space into a square, and aligningThe squares are subjected to gridding treatment, so that the spacecraft measurement model space is composed of a plurality of small squares, and the points are conveniently measured and solved; the magnetic field and vertical gradient tensor of a grid point of a certain plane of a spacecraft measurement model space are measured by a magnetometer to measure the three-direction magnetic induction intensity B of each grid point position_x,B_y,B_zThen, the differential method of formula (1) is used to calculate the vertical gradient tensors Bzz, Byz and Bxz:

establishing an equation of the information of the vertical component of the magnetic field at each grid point, establishing an equation set by using four adjacent grid points, solving the information of the magnetic anomaly position (x, y, z) until all the grid points are covered,

the equation is (x-x)₀)B_zz+(y-y₀)B_yz+(z-z₀)B_xz＝-3(B_z-b_z) (2)

Wherein Bz is the vertical component of the magnetic field at the measuring point, Bz is the vertical component of the background magnetic field at the measuring point, x₀,y₀,z₀Is the coordinate of the measuring point, the magnetic abnormal position information x, y, z;

establishing an equation set (3) for every four measuring points, solving the information of the magnetic anomaly position (x, y, z), establishing the equation set until all the points are covered,

2. The method of claim 1, wherein the magnetic anomaly data of the spacecraft measurement model space surface is a magnetic field and a magnetic field vertical tensor of a certain surface grid node of the measurement model space.