Magnetic field simulation test environment generator for geomagnetic navigation system

Abstract

The device for generating a magnetic field simulation test environment for a geomagnetic navigation system relates to the field of geomagnetic navigation test technology, and solves the technical problems in the prior art that a complex geomagnetic gradient field cannot be provided, and a uniform and stable geomagnetic field experimental environment with controllable size and direction and magnetic anomaly environment cannot be generated to construct a reasonable geomagnetic field experimental environment. The present invention can provide a geomagnetic navigation device test environment with controllable size and direction and low interference, and provides an environmental basis for verifying the reliability of the navigation algorithm; the magnetic field area simulating the geomagnetic field magnetic anomaly environment is designed and combined by the host computer simulation to quickly obtain a high-resolution geomagnetic reference map database in the magnetic field test space, so that the construction of the geomagnetic map is more convenient, and there is no need to spend a lot of manpower and material resources for field measurement and data verification; the mechanical structure is simple, easy to install and transport; it can be modified according to the required environment size, and the size design is flexible, which can meet the test environment requirements of the geomagnetic navigation system under complex conditions.

Description

Technical Field

[0001] The invention relates to the technical field of geomagnetic navigation testing, and in particular to a device for generating a magnetic field simulation testing environment for a geomagnetic navigation system. Background Art

[0002] Geomagnetic navigation is a method of guiding and correcting the movement of a carrier by matching the geomagnetic field data measured by a magnetic field sensor with a geomagnetic database. Geomagnetic navigation is widely used in a variety of navigation and positioning fields such as aviation, aerospace, ground and underwater vehicles due to its all-regional, all-weather, and passive anti-interference characteristics.

[0003] Geomagnetic navigation technology mainly includes three parts: the construction of geomagnetic field reference map database, geomagnetic data measurement and geomagnetic navigation algorithm. The smooth implementation of these three parts depends on a reliable geomagnetic field environment. Although geomagnetic field simulation models such as IGRF and WMM models can be used to make a preliminary construction of the geomagnetic field on the total geomagnetic field, some magnetic anomaly areas cannot be well reflected and the magnetic field resolution is low. Generally, the construction of an accurate geomagnetic field model requires expensive magnetic measurement equipment to conduct a large number of field measurements, and the testing process consumes a lot of manpower and material resources. In addition, it is very susceptible to magnetic field interference caused by uncertain catastrophic space weather and human activities during field measurements, resulting in insufficient data reliability, which adds non-negligible interference to the subsequent verification of geomagnetic navigation algorithms. In addition, the geomagnetic field magnetic anomaly environment that the geomagnetic matching navigation algorithm needs to provide during testing cannot be well solved by the existing technical patents and methods in papers.

[0004] CN103901361B discloses a magnetic field simulation system based on a three-dimensional square Helmholtz coil. In the field of geomagnetic navigation, this system cannot provide a more complex geomagnetic gradient field and simulation of magnetic anomaly areas. CN104748762B discloses a design and manufacturing method for a high-performance geomagnetic field simulation device. The device is relatively complex and cannot effectively simulate magnetic anomaly areas. The magnetic field generating devices of the above inventions have their own limitations in the field of geomagnetic navigation. They cannot produce a uniform and stable geomagnetic field experimental environment with controllable size and direction and a reasonable magnetic anomaly environment, and are very likely to cause unnecessary environmental interference to the experimental results. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a device for generating a magnetic field simulation test environment for a geomagnetic navigation system, which solves the technical problems in the prior art that a complex geomagnetic gradient field cannot be provided and a uniform, stable, controllable size and direction, and magnetic anomaly environment cannot be generated to construct a reasonable geomagnetic magnetic field experimental environment.

[0006] The technical solution adopted by the present invention to solve the technical problem is as follows:

[0007] A device for generating a magnetic field simulation test environment for a geomagnetic navigation system, the device comprising: a host computer, a direct current source, a three-dimensional square Helmholtz coil, a magnetic anomaly simulation device and a magnetic field sensor; the host computer sets the magnitude and direction of the current on the three-dimensional square Helmholtz coil, and controls the direct current source to load the current of the direct current source on the three-dimensional square Helmholtz coil, change the magnitude and direction of the current of the three-dimensional square Helmholtz coil, and make the magnetic field in the three-dimensional square Helmholtz coil be superimposed in three parts; the magnetic anomaly simulation device changes the magnetic field in the three-dimensional square Helmholtz coil; the magnetic field sensor collects the magnetic field in the three-dimensional square Helmholtz coil, and uploads the magnetic field data to the host computer; the host computer adjusts the magnitude and direction of the direct current power flow according to the set magnetic field value to achieve the magnetic field value in the ideal magnetic field simulation test environment.

[0008] Preferably, the host computer is connected to the DC current source, and the DC current source is connected to the three-dimensional square Helmholtz coil; the magnetic anomaly simulation device is arranged in or near the three-dimensional square Helmholtz coil; the magnetic field sensor is arranged in the three-dimensional square Helmholtz coil and connected to the host computer.

[0009] Preferably, the three-dimensional square Helmholtz coil is orthogonally formed by three groups of mutually perpendicular square Helmholtz coil groups, corresponding to the three components of the magnetic field of the geomagnetic field; each group of square Helmholtz coils is coaxially placed and has the same number of turns, winding method and current direction.

[0010] Preferably, the magnetic anomaly simulation device comprises: a positioning plate, a supporting frame, a positioning rod and a base; the upper and lower ends of the multiple supporting frames are respectively mounted on the positioning plate and the base, and are evenly distributed around the positioning plate and the base; the three-dimensional square Helmholtz coil is arranged on the base, and is located within the range surrounded by the positioning plate, the supporting frame and the base; the positioning plate is provided with a plurality of positioning holes, one end of the positioning rod is mounted on the positioning plate through the positioning hole, and the other end of the positioning rod is located in the three-dimensional square Helmholtz coil and is provided with a strong magnet.

[0011] Preferably, an array of positioning holes is provided on the positioning plate.

[0012] Preferably, the structure of the positioning plate is the same as that of the base.

[0013] Preferably, the positioning rod is provided with scale values.

[0014] Preferably, the positioning rod is mounted on the positioning plate via a positioning block.

[0015] Preferably, the strong magnet is arranged in the three-dimensional square Helmholtz coil group via a tray mounted on the positioning rod.

[0016] Preferably, the magnetic field of the three-dimensional square Helmholtz coil is:

[0017]

[0018]

[0019]

[0020] Of which: 2a x , 2a y , 2a z are the side lengths of the three coils, 2l x is the spacing between a group of coils in the X direction, 2l y is the spacing between a group of coils in the Y direction, 2l z is the spacing between a group of coils in the Z direction, μ 0 is the vacuum magnetic permeability, N is the number of winding turns, I x ,I y ,I z is the control current of the three groups of DC current sources, B x , B y , B z is the magnitude of the three components of the magnetic field at the position (x, y, z).

[0021] The beneficial effects of the present invention are:

[0022] 1. The present invention can provide a geomagnetic navigation device test environment with controllable size and direction and low interference, thus providing an environmental basis for verifying the reliability of the navigation algorithm.

[0023] 2. The present invention can independently design and combine magnetic field areas that simulate the geomagnetic field anomaly environment. Combined with the host computer simulation, a high-resolution geomagnetic reference map database in the magnetic field test space can be quickly obtained, making the construction of the geomagnetic map more convenient without spending a lot of manpower and material resources on field measurement and data verification.

[0024] 3. The mechanical structure of the present invention is simple, easy to install and transport. It can be modified according to the required environment size, and the size design is flexible, which can meet the test environment requirements of the geomagnetic navigation system in complex situations. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Principle block diagram of the device for generating a magnetic field simulation test environment for a geomagnetic navigation system of the present invention.

[0026] Figure 2Schematic diagram of the setup of a 3D square Helmholtz coil set.

[0027] Figure 3 A schematic structural diagram of a device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to the present invention.

[0028] In the figure: 1. Xa coil, 2. Xb coil, 3. Ya coil, 4. Yb coil, 5. Za coil, 6. Zb coil, 7. supporting frame, 8. three-dimensional square Helmholtz coil group, 9. positioning plate, 10. positioning rod, 11. fixing block, 12. tray, 13. base. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0030] like Figure 1 As shown, a device for generating a magnetic field simulation test environment for a geomagnetic navigation system includes: a host computer, a direct current source, a three-dimensional square Helmholtz coil 8, a magnetic anomaly simulation device, and a magnetic field sensor; the host computer sets the magnitude and direction of the current on the three-dimensional square Helmholtz coil 8 according to the required simulation environment, and controls the direct current source to load the current of the direct current source on the three-dimensional square Helmholtz coil 8, changes the magnitude and direction of the current of the three-dimensional square Helmholtz coil 8, and makes the magnetic field in the three-dimensional square Helmholtz coil 8 superimpose three parts, so as to achieve the desired magnetic field environment. The magnetic anomaly simulation device changes the magnetic field in the three-dimensional square Helmholtz coil 8; the magnetic field sensor collects the magnetic field in the three-dimensional square Helmholtz coil 8, and uploads the magnetic field data to the host computer, and the host computer adjusts the magnitude and direction of the direct current power flow according to the set magnetic field value to achieve the magnetic field value in the ideal magnetic field simulation test environment.

[0031] The connection relationship between the various components is that the host computer is connected to the DC current source, and the DC current source is connected to the three-dimensional square Helmholtz coil 8; the magnetic anomaly simulation device is arranged in or near the three-dimensional square Helmholtz coil 8; the magnetic field sensor is arranged in the three-dimensional square Helmholtz coil 8 and connected to the host computer.

[0032] like Figure 2 As shown, the three-dimensional square Helmholtz coil 8 is orthogonally formed by three groups of mutually perpendicular square Helmholtz coils, corresponding to the three components of the magnetic field of the earth's magnetic field; Xa coil 1 and Xb coil 2 form the X-direction coil, Ya coil 3 and Yb coil 4 form the Y-direction coil, Za coil 5 and Zb coil 6 form the Z-direction coil, and each group of square Helmholtz coils are coaxially placed and have the same number of turns, winding method and current direction. The magnetic field of the three-dimensional square Helmholtz coil 8 is:

[0033]

[0034]

[0035]

[0036] Of which: 2a x , 2a y , 2a z are the side lengths of the three coils, 2l x is the spacing between a group of coils in the X direction, 2l y is the spacing between a group of coils in the Y direction, 2l z is the spacing between a group of coils in the Z direction, μ 0 is the vacuum magnetic permeability, N is the number of winding turns, I x ,I y ,I z is the current of each group of the three-dimensional square Helmholtz coil 8 under the control of three groups of DC current sources, B x , B y , B z is the magnitude of the three components of the magnetic field at the position (x, y, z).

[0037] In order to reflect the magnetic anomaly environment, the magnetic anomaly simulation device inside the three-dimensional square Helmholtz coil 8 realizes the magnetic field changes generated by the simulated magnetic anomaly area in the coil space. Figure 3As shown, the magnetic anomaly simulation device includes: a support frame 7, a positioning plate 9, a positioning rod 10, a fixing block 11, a tray 12 and a base 13; the upper and lower ends of the multiple support frames 7 are respectively installed on the positioning plate 9 and the base 13, and are evenly distributed around the positioning plate 10 and the base 13; in this embodiment, the structure of the positioning plate 9 is the same as that of the base 13, both of which are square structures, and the support frames 7 are located at the four corners of the positioning plate 10 and the base 13, and are perpendicular to the positioning plate 10 and the base 13; each support frame 7 is parallel to each other. The three-dimensional square Helmholtz coil 8 is arranged on the base 13, and is located within the range surrounded by the positioning plate 9, the support frame 7 and the base 13; the positioning plate 9 is provided with a plurality of positioning holes, and in this embodiment, the positioning holes are arranged in a matrix form and penetrate the positioning plate 9. One end of the positioning rod 10 is installed on the positioning plate 9 through the positioning hole, and the fixing block 11 passes through the positioning rod 10 to fix the positioning rod 10 on the positioning plate 9. The other end of the positioning rod 10 is located in the three-dimensional square Helmholtz coil 8, and a tray 12 is provided, and the strong magnet is placed on the tray 12. According to environmental requirements, the positioning rod 10 can be inserted into different positioning holes. There are scale values ​​on the positioning rod 10, and the specific position of the strong magnet in the three-dimensional square Helmholtz coil 8 can be determined by selecting different positioning holes and selecting the depth of the strong magnet according to the scale values ​​on the positioning rod 10.

[0038] An implementation step of evaluating and testing a geomagnetic navigation system using a geomagnetic navigation system magnetic field simulation test environment generator is as follows:

[0039] a. Connect the host computer control line to three sets of DC current sources, and connect the DC current source outputs to the corresponding square Helmholtz coils respectively. Connect the output of the internal magnetic field sensor of the three-dimensional Helmholtz coil 8 to the host computer to provide a closed-loop feedback signal, and calibrate the zero bias of the device at this time to offset the interference caused by the background magnetic field.

[0040] b. Select a strong magnet to be fixed in the tray 12 at the lower end of the positioning rod 10, select a suitable positioning hole, and adjust the depth of the positioning rod 10 in the three-dimensional Helmholtz coil 8, and then fix the positioning rod 10 on the positioning plate 9.

[0041] c. The geomagnetic navigation device to be measured is fixed at the center of the three-dimensional square Helmholtz coil 8 or fixed on a three-axis non-magnetic turntable and then placed into the inner space of the three-dimensional square Helmholtz coil 8.

[0042] d. Set or select the required simulation test magnetic field environment in the host computer, and the host computer will send the corresponding geomagnetic reference map database to the geomagnetic navigation system for matching and positioning.

[0043] e. The geomagnetic navigation system will send the data measured by the sensor to the host computer after the navigation algorithm outputs, so as to further evaluate the accuracy of the geomagnetic navigation algorithm and its reliability under different levels of magnetic anomaly environments. The host computer will record and save the current source setting plan and real-time magnetic field data in a .txt file or .excel file for subsequent data analysis and processing.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for generating a magnetic field simulation test environment for a geomagnetic navigation system, characterized in that: The device comprises: a host computer, a direct current source, a three-dimensional square Helmholtz coil, a magnetic anomaly simulation device and a magnetic field sensor; the host computer sets the magnitude and direction of the current on the three-dimensional square Helmholtz coil, controls the direct current source, loads the current of the direct current source on the three-dimensional square Helmholtz coil, changes the magnitude and direction of the current of the three-dimensional square Helmholtz coil, and makes the magnetic field in the three-dimensional square Helmholtz coil be superimposed in three parts; the magnetic anomaly simulation device changes the magnetic field in the three-dimensional square Helmholtz coil; the magnetic field sensor collects the magnetic field in the three-dimensional square Helmholtz coil, and uploads the magnetic field data to the host computer. The host computer adjusts the size and direction of the DC power flow according to the set magnetic field value to achieve the magnetic field value in the ideal magnetic field simulation test environment; the magnetic anomaly simulation device includes: a positioning plate, a support frame, a positioning rod and a base; the upper and lower ends of the multiple support frames are respectively installed on the positioning plate and the base, and are evenly distributed around the positioning plate and the base; the three-dimensional square Helmholtz coil is arranged on the base, located within the range surrounded by the positioning plate, the support frame and the base; the positioning plate is provided with a plurality of positioning holes, one end of the positioning rod is installed on the positioning plate through the positioning hole, and the other end of the positioning rod is located in the three-dimensional square Helmholtz coil and is provided with a strong magnet.

2. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The host computer is connected to the DC current source, and the DC current source is connected to the three-dimensional square Helmholtz coil; the magnetic anomaly simulation device is arranged in or near the three-dimensional square Helmholtz coil; the magnetic field sensor is arranged in the three-dimensional square Helmholtz coil and connected to the host computer.

3. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1 or 2, characterized in that: The three-dimensional square Helmholtz coil is orthogonally formed by three groups of mutually perpendicular square Helmholtz coils, corresponding to the three components of the magnetic field of the earth's magnetic field; each group of square Helmholtz coils is coaxially placed and has the same number of turns, winding method and current direction.

4. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The positioning plate is provided with a positioning hole array.

5. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The structure of the positioning plate is the same as that of the base.

6. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The positioning rod is provided with scale values.

7. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The positioning rod is installed on the positioning plate through a positioning block.

8. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The strong magnet is arranged in the three-dimensional square Helmholtz coil via a tray mounted on the positioning rod.

9. The device for generating a magnetic field simulation test environment for a geomagnetic navigation system according to claim 1, characterized in that: The magnetic field of the three-dimensional square Helmholtz coil is: Of which: 2a x , 2a y , 2a z are the side lengths of the three coils, 2l x is the spacing between a group of coils in the X direction, 2l y is the spacing between a group of coils in the Y direction, 2l z is the spacing between a group of coils in the Z direction, μ0 is the vacuum magnetic permeability, N is the number of winding turns, I x ,I y ,I z is the control current of the three groups of DC current sources, B x , B y , B z is the magnitude of the three components of the magnetic field at the position (x, y, z).

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