Indoor Magnetic Navigation Verification System and its Working Method

Abstract

This invention provides an indoor magnetic navigation verification system and its operating method. The system includes an experimental platform, an optical positioning system, and a display terminal. The experimental platform, from bottom to top, comprises a support layer, a magnetic source deployment layer, a scene support layer, and a carrier operation layer. The magnetic source deployment layer contains a magnetic source array capable of receiving magnetic source control signals sent by a host computer. The magnetic source array includes multiple magnetic sources. A mobile carrier runs on the carrier operation layer. An edge computer acquires the motion data of the mobile carrier and outputs it to the host computer, which calculates the estimated trajectory of the mobile carrier. The optical positioning system includes multiple camera devices for acquiring the actual trajectory of the mobile carrier. The display terminal acquires the actual trajectory output by the optical positioning system and compares and displays the estimated trajectory with the actual trajectory. This invention also provides the operating method of the system. This invention can construct a verification system that can be repeatedly verified.

Description

Technical Field

[0001] This invention relates to the technical field of magnetic field navigation, and in particular to an indoor magnetic navigation verification system and a method for operating such a system. Background Technology

[0002] Navigation and orientation technologies possess advantages such as independence from external electromagnetic radiation, strong stealth capabilities, and the ability to operate sustainably in complex environments, making them highly valuable for applications in indoor positioning and navigation, autonomous navigation of unmanned platforms, and perception of complex environments. For geomagnetic navigation and artificial magnetic field-assisted navigation technologies, the performance of the applied algorithms is not only affected by the spatial distribution of the magnetic field but also closely related to changes in the carrier's attitude, the platform's own magnetic interference, sensor installation errors, and the spatiotemporal synchronization accuracy during motion. Therefore, relying solely on offline data processing or local static testing is often insufficient to accurately evaluate the performance of magnetic navigation and magnetic compensation algorithms under real-world operating conditions.

[0003] Existing magnetic navigation experimental devices are mostly designed around a single purpose. Some devices are only used for magnetic field demonstration or local magnetic field adjustment, which can demonstrate that magnetic fields can be constructed, but it is difficult to stably form a repeatable and adjustable target magnetic field distribution over a large working area. Other devices focus on offline algorithm verification. Although they can complete magnetic field map matching or trajectory calculation, they lack experimental conditions that combine with real motion platforms, real sensors, and real control links. Some devices have certain hardware demonstration capabilities, but lack a unified truth acquisition and error evaluation mechanism, and cannot form comparable and reproducible quantitative results.

[0004] The shortcomings of existing experimental setups are even more apparent when it comes to platform magnetic interference compensation. During operation, the magnetic field measurements of a mobile platform are often superimposed with the influence of the ambient magnetic field, the platform's magnetic source, the platform's own magnetic interference, and measurement deviations introduced by attitude changes. Without a controllable magnetic field environment, a standardized platform operating space, a stable optical positioning system, and a unified data acquisition and control link, it is difficult to objectively evaluate the improvement before and after compensation, and it is also not conducive to the joint verification of magnetic navigation algorithms and magnetic compensation algorithms.

[0005] In general, existing magnetic navigation experimental devices have the following problems: First, the ability to construct a magnetic field environment is insufficient. Existing magnetic navigation experimental devices mostly use a single magnet, a small number of fixed magnetic sources, or a fixed scene arrangement, which makes it difficult to form a continuous, adjustable, and repeatable target magnetic field distribution within a large working area. This cannot meet the requirements for magnetic field map acquisition, magnetic navigation path planning, and multi-condition comparative verification.

[0006] Second, dynamic verification conditions are insufficient. Existing magnetic navigation experimental devices focus on static sampling or offline data playback, lacking real moving carriers, real sensor links, and real control links, and therefore cannot reflect the actual impact of magnetic field changes, attitude changes, and the superposition of mileage errors during carrier movement.

[0007] Third, there is a lack of true value comparison. Some existing magnetic navigation experimental devices can only output algorithm estimation results and cannot simultaneously obtain high-precision position and trajectory true values. Therefore, it is impossible to quantitatively evaluate navigation errors, compensation effects, and repeatability.

[0008] Fourth, the system integration is insufficient. Existing magnetic navigation experimental devices often separate magnetic field construction, carrier motion, sensor acquisition, algorithm operation, visualization, and interactive control, resulting in complex experimental organization, inconsistent data links, and difficulty in supporting continuous iteration and engineering verification.

[0009] Fifth, there is a lack of specific verification conditions for platform magnetic interference compensation. Existing magnetic navigation experimental devices typically do not unify the controllable magnetic field environment, carrier motion state, attitude information, and true-value positioning, making it difficult for platform magnetic interference compensation algorithms to complete closed-loop verification under conditions close to actual applications. Summary of the Invention

[0010] The primary objective of this invention is to provide an indoor magnetic navigation verification system that addresses the challenges of replicating magnetic field environments, insufficient dynamic verification conditions for carriers, and a lack of true value comparisons.

[0011] The second objective of this invention is to provide a working method for implementing the above-described indoor magnetic navigation verification system.

[0012] To achieve the first objective of this invention, the indoor magnetic navigation verification system provided by this invention includes an experimental platform, an optical positioning system, and a display terminal. The experimental platform, from bottom to top, comprises a support layer, a magnetic source deployment layer, a scene support layer, and a carrier operation layer. The magnetic source deployment layer contains a magnetic source array capable of receiving magnetic source control signals sent by a host computer. The magnetic source array includes multiple magnetic sources, each generating a corresponding magnetic field according to the magnetic source control signal. A mobile carrier runs on the carrier operation layer. An edge computer acquires the motion data of the mobile carrier and outputs it to the host computer, which calculates the estimated trajectory of the mobile carrier. The optical positioning system includes multiple camera devices for acquiring the actual trajectory of the mobile carrier. The display terminal acquires the actual trajectory output by the optical positioning system and compares and displays the estimated trajectory with the actual trajectory.

[0013] As can be seen from the above scheme, the present invention can set up a mobile carrier on an experimental platform and generate a target magnetic field environment by controlling the operation of the magnetic source array, so that the mobile carrier can run in the pre-set target magnetic field environment. Then, the actual trajectory of the mobile carrier is collected by an optical positioning system, and the indoor navigation algorithm is verified by comparing the estimated trajectory with the actual trajectory.

[0014] Because this invention utilizes an experimental platform, particularly by controlling the operation of a magnetic source array to generate the target magnetic field environment, this environment can be repeatedly reproduced. This allows for the reproducible construction of a magnetic field environment, enabling multiple experiments to be conducted under identical conditions and environments, resulting in clearer comparisons of experimental results. Furthermore, the estimated trajectory can be compared with the actual trajectory via a host computer, and the results can be displayed on a terminal for a more intuitive understanding of the experimental outcomes.

[0015] A preferred embodiment is that each magnetic source includes a permanent magnet and a drive unit, the drive unit driving the permanent magnet to rotate in at least two directions.

[0016] It can be seen that by driving the permanent magnet of each magnetic source to rotate in multiple directions, different magnetic field conditions can be set as needed, making the experiment more flexible and enabling targeted simulation of specific magnetic field environments.

[0017] A further option is that the drive unit includes at least two sets of drive mechanisms, each set of drive mechanisms being used to drive the permanent magnet to rotate in one direction; at least two directions are perpendicular to each other.

[0018] Therefore, by using multiple sets of drive mechanisms to drive the permanent magnet to rotate in multiple different directions, the direction control of the permanent magnet can be achieved through a simple and reliable transmission mechanism.

[0019] A further approach is to arrange multiple magnetic sources in an array on the magnetic source deployment layer. An array of multiple magnetic sources is advantageous for creating a more complex magnetic field environment.

[0020] A further approach involves mounting the edge computer on a mobile platform, which is also equipped with a magnetic field sensor and an inertial sensor.

[0021] Therefore, placing the edge computer on a mobile carrier, rather than setting up a separate edge computer, can reduce the size of the entire indoor magnetic navigation verification system.

[0022] A further proposed solution is that when the mobile carrier sends motion data to the host computer, it also sends the data collected by the magnetic field sensor and the inertial sensor to the host computer.

[0023] A further approach is to arrange two or more micro-terrain models in the scene carrying layer.

[0024] To achieve the second objective mentioned above, the working method of the indoor magnetic navigation verification system provided by the present invention includes setting a target magnetic field environment and a target trajectory for a mobile vehicle; the host computer sends a magnetic source control signal to the magnetic source array according to the target magnetic field environment, so that each magnetic source generates a corresponding magnetic field according to the magnetic source control signal; the mobile vehicle moves according to the target trajectory and collects motion data and outputs it to the host computer, which calculates the estimated trajectory of the mobile vehicle; the optical positioning system acquires the actual trajectory of the mobile vehicle; and the display terminal acquires the actual trajectory output by the optical positioning system and compares and displays the estimated trajectory with the actual trajectory.

[0025] As can be seen from the above scheme, this invention constructs a target magnetic field environment through a magnetic source array, places a mobile carrier on an experimental platform, acquires the actual trajectory of the mobile carrier through an optical positioning system, compares the actual trajectory with the estimated trajectory, and displays the comparison results on a display terminal, allowing users to intuitively understand the comparison results. Furthermore, since the target magnetic field environment constructed by the magnetic source array can be reproduced, this invention can construct a reproducible verification environment.

[0026] A preferred embodiment is that, after each magnetic source receives a magnetic source control signal, the permanent magnet on the magnetic source rotates in at least two directions to change the position of the permanent magnet and generate a magnetic field of a preset magnetic field strength.

[0027] It can be seen that by controlling the pose of each magnetic source, different magnetic field environments can be constructed, making the construction of magnetic field environments very flexible.

[0028] A further approach is that, as the mobile carrier moves along the target trajectory, it uses magnetic field signals collected by a magnetic field sensor and a preset navigation algorithm to move along the target trajectory.

[0029] Therefore, it can be seen that the mobile carrier calculates its trajectory based on the magnetic field signals collected by the magnetic field sensor and the preset navigation algorithm. Thus, the method of the present invention can verify whether the algorithm used by the mobile carrier is accurate, and can also verify the accuracy of the data collected by the magnetic field sensor, inertial sensor and other sensors. Attached Figure Description

[0030] Figure 1 This is a structural block diagram of an embodiment of the indoor magnetic navigation verification system of the present invention.

[0031] Figure 2 This is a schematic diagram of the experimental platform in an embodiment of the indoor magnetic navigation verification system of the present invention.

[0032] Figure 3 This is a schematic diagram of the structure of the support layer of the experimental platform in an embodiment of the indoor magnetic navigation verification system of the present invention.

[0033] Figure 4 This is a schematic diagram of the magnetic source deployment layer of the experimental platform in an embodiment of the indoor magnetic navigation verification system of the present invention.

[0034] Figure 5 This is a schematic diagram of the scene-bearing layer of the experimental platform in an embodiment of the indoor magnetic navigation verification system of the present invention.

[0035] Figure 6 This is a schematic diagram of the magnetic source structure of the experimental platform in an embodiment of the indoor magnetic navigation verification system of the present invention.

[0036] Figure 7 This is a flowchart of the magnetic field generation and modulation process in an embodiment of the working method of the indoor magnetic navigation verification system of the present invention.

[0037] Figure 8 This is a flowchart of the indoor navigation verification process in an embodiment of the working method of the indoor magnetic navigation verification system of the present invention.

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0039] The indoor magnetic navigation verification system of this invention is used to verify the hardware and software algorithms of magnetic field navigation. Specifically, the system constructs an adjustable and reproducible target magnetic field environment within an indoor work area, and verifies carrier operation, sensor data acquisition, magnetic field map acquisition, magnetic navigation algorithm operation, and platform magnetic interference compensation algorithm on a unified platform. Simultaneously, it uses an optical positioning system to obtain the true position of the moving carrier, thus forming the carrier's true trajectory. By comparing the true trajectory with the estimated trajectory, quantifiable and reproducible evaluation results are generated. Furthermore, the verification system improves experimental organization efficiency and future scalability through human-computer interaction and visualization.

[0040] Example of an indoor magnetic navigation verification system: See Figure 1 The indoor magnetic navigation verification system of this embodiment has a multi-layer experimental platform 100, which includes a four-layer structure, see [link to documentation]. Figure 2From bottom to top, the structure consists of a support layer 10, a magnetic source deployment layer 20, a scene support layer 30, and a carrier operation layer 40. The magnetic source deployment layer 20 has a magnetic source array 21, which contains multiple magnetic sources arranged in an array. The carrier operation layer 40 has a mobile carrier 41 running on it. The mobile carrier 41 runs a magnetic navigation algorithm. Based on the magnetic field generated by the magnetic source array 21 and a pre-set target trajectory, the magnetic navigation algorithm calculates the direction of movement, enabling the mobile carrier 41 to operate on the carrier operation layer 40.

[0041] The verification system is also equipped with an optical positioning system 55, which includes multiple imaging devices set around the experimental platform 100 to acquire the real trajectory of the moving carrier 41.

[0042] The verification system also includes a human-computer interaction terminal 51, a host computer 52, and a closed-loop stepper driver 53. The human-computer interaction terminal 51 is used to realize human-computer interaction, such as receiving user input commands, including the magnetic field map selected by the user. The host computer 52 can obtain the estimated trajectory of the mobile carrier 41 through the edge computer 44 and the actual trajectory of the mobile carrier 41 through the optical positioning system 55. It compares and analyzes the estimated trajectory and the actual trajectory to form a comparison result, which can be transmitted to the human-computer interaction terminal 51. The human-computer interaction terminal 51 displays the estimated trajectory and the actual trajectory of the mobile carrier 41, as well as the comparison result, allowing the user to intuitively understand the difference between the actual trajectory formed by the actual operation of the mobile carrier 41 and the estimated trajectory, and thus analyze the problems of the corresponding sensors or magnetic navigation algorithms. In addition, the host computer 52 can output magnetic source control signals to the magnetic source array 21 through the closed-loop stepper driver 53 to control the pose of each magnetic source, the magnetic field strength generated by each magnetic source, etc., thereby forming a target magnetic field environment on the experimental platform 100.

[0043] See Figure 2 The experimental platform 100 adopts a multi-layered structure with overall dimensions of approximately 3m × 3m × 0.8m. It preferably uses aluminum profiles and acrylic materials to construct the main frame, in order to reduce the additional impact of the experimental platform 100 on the experimental magnetic field environment. See [link to relevant documentation]. Figure 3 The bottom layer of the experimental platform 100 is a support layer 10, which serves as both a wiring harness concealment layer and a basic support layer. The support layer 10 has a frame 11, within which a storage space is formed to accommodate wiring, power supply devices, and basic installation structures, while also ensuring overall strength and ease of maintenance.

[0044] See Figure 1 and Figure 4A magnetic source deployment layer 20 is positioned above the support layer 10 and has a frame 22. Support columns 23 are positioned at the four corners of the frame 22. Multiple magnetic sources are mounted on the magnetic source deployment layer 20 to form a magnetic source array 21, with the multiple magnetic sources arranged in an array. Each magnetic source can rotate in at least two directions. For example, each magnetic source can receive magnetic source control signals sent by the host computer 52, controlling the rotation direction and the magnetic field strength emitted by each source according to the control signals. The magnetic fields generated by multiple magnetic sources are superimposed to form the target magnetic field environment required for the experiment. Therefore, the target magnetic field environment of this invention is a controllable and adjustable magnetic field environment.

[0045] See Figure 5 The scene-carrying layer 30 is positioned above the magnetic source deployment layer 20 and comprises four regions, each corresponding to a different terrain. Specifically, the scene-carrying layer 30 features four micro-terrain models: forest, grassland, ocean, and desert, corresponding to the first region 31, the second region 32, the third region 33, and the fourth region 34, respectively. Of course, in practical applications, these can be replaced with scene modules corresponding to other experimental themes as needed.

[0046] The carrier operation layer 40 is positioned above the scene carrier layer 30, see [reference]. Figure 1 The mobile carrier 41 operates on the carrier operation layer 40. Preferably, the mobile carrier 41 is equipped with multiple sensors, such as a magnetic field sensor 42 and an inertial sensor 43, and also includes an edge computer 44. The carrier operation layer 40 includes a flat operating plane as the actual driving plane of the mobile carrier 41. The magnetic field sensor 42 can collect magnetic field data around the mobile carrier 41, and the inertial sensor 43 can collect inertial data during the operation of the mobile carrier 41, including speed, acceleration, azimuth, angular rate, etc. The edge computer 44 can acquire the data from the magnetic field sensor 42 and the inertial sensor 43, and calculate the operating path of the mobile carrier 41 based on a pre-set magnetic navigation algorithm and a user-specified magnetic field map and target trajectory. In addition, during the actual operation of the mobile carrier 41, the edge computer 44 also calculates the trajectory of the mobile carrier 41 in real time to form an estimated trajectory, and sends the estimated trajectory to the host computer 52.

[0047] The experimental platform 100 adopts a layered structure, which spatially separates the magnetic field construction unit from the carrier motion plane. This facilitates the formation of the target magnetic field environment on the upper working surface without exposing the underlying magnetic source mechanism. Even if the carrier operation layer 40 is adjusted, the operation of the magnetic source deployment layer 20 will not be affected. In addition, the support layer 10 facilitates wiring harness management, module assembly and disassembly, and subsequent maintenance, and also provides a structural basis for scene replacement, platform expansion, and configuration for different experimental conditions.

[0048] The magnetic source array 21 in the magnetic source deployment layer 20 consists of nine arrays arranged in a 3×3 configuration. (See also...) Figure 6 Each magnetic source 25 is equipped with a permanent magnet 26, and each permanent magnet 26 has at least two rotational degrees of freedom, each capable of 360° rotation, thereby changing the attitude of the permanent magnet 26 and adjusting its magnetic field contribution in the working area. In addition to the permanent magnet 26, each magnetic source also has two sets of drive mechanisms, each used to drive the permanent magnet 26 to rotate in one direction. For example, the first set of drive mechanisms includes a first gear set 27 and a first drive motor. The first gear set 27 includes two meshing bevel gears, capable of driving the permanent magnet 26 to rotate in the first direction, with the rotation axis horizontal. The second set of drive mechanisms includes a second gear set 29 and a second drive motor. The second gear set 29 can drive the rotating base 28 to rotate. Since both the first set of drive mechanisms and the permanent magnet 26 are mounted on the rotating base 28, the permanent magnet 26 also rotates after the rotating base 28 rotates, thus enabling the permanent magnet 26 to rotate in the second direction, with the rotation axis vertical. In this way, through two sets of drive mechanisms, the permanent magnet 26 can be rotated independently in two mutually perpendicular directions.

[0049] Furthermore, during system verification, the host computer 52 can generate target state parameters for each magnetic source based on the target magnetic field environment, a preset magnetic field map, or experimental conditions. Then, through a control link, it drives the permanent magnets 26 of each magnetic source to adjust their attitude, enabling multiple magnetic sources to form a superimposed magnetic field within the upper working area. In this way, the experimental platform 100 is no longer limited to displaying a fixed magnetic field, but can construct multiple target magnetic field distributions within the same working area, providing a unified scenario for magnetic field map acquisition, magnetic navigation path verification, and magnetic compensation evaluation.

[0050] The mobile carrier 41, as the verification object, operates on the top layer of the experimental platform 100. The mobile carrier 41 is preferably a small wheeled chassis unmanned vehicle with dimensions of approximately 25cm × 15cm × 9cm, a light-load speed of approximately 1.45m / s, a maximum load of approximately 6kg, and a total vehicle weight of approximately 1.65kg. In addition to the magnetic field sensor 42, inertial sensor 43, and edge computer 44, the mobile carrier 41 can also be equipped with an odometer and encoder. The odometer and encoder are used to supplement the carrier's motion information, providing auxiliary input for the magnetic navigation algorithm and magnetic field compensation algorithm. Furthermore, the installation orientation of the magnetic field sensor 42 is consistent with that of the inertial sensor 43. The coordinate system of the mobile carrier 41 is defined as the X-axis directly in front of the unmanned vehicle, the Y-axis to the left, and the Z-axis vertically upward. The sampling rate of the odometer and encoder is preferably 250Hz. Zero-bias calibration is performed before the experiment, but temperature drift calibration is not performed. The timing of all sensors on the mobile carrier 41 is uniformly synchronized by the edge computer 44.

[0051] Under indoor experimental conditions, the inertial sensor 43 is connected to the edge computer 44 via a serial port. The data is analyzed and processed in double precision within the system. The sampling rate is preferably 100Hz, and the GNSS function is preferably turned off. Only the information output by the inertial sensor 43 is used for attitude calculation.

[0052] In this embodiment, the optical positioning system 55 captures images of the mobile carrier 41 and calculates the actual trajectory of the mobile carrier based on the captured images. The difference between the actual trajectory and the estimated trajectory is used as a truth reference for algorithm verification. Specifically, the optical positioning system 444 is equipped with multiple imaging devices, which can be deployed around the outer perimeter of the experimental platform 100. Each imaging device is installed at a height of approximately 2.5m above the ground, and the deployment of the multiple imaging devices must ensure that their imaging range covers the entire experimental platform 100. The optical positioning system 44 allows the present invention to compare the estimated trajectory output by the algorithm with the actual trajectory, thereby quantitatively analyzing navigation errors, repeatability, differences before and after compensation, and system stability.

[0053] The host computer 52 receives data input from the human-machine interface terminal 51. For example, based on the input requirements of the target magnetic field environment and the target trajectory, it generates control signals for each magnetic source 25 in the magnetic source array 21 and sends these signals to each magnetic source 25 in the magnetic source array 21 via a closed-loop stepper driver 53, thereby controlling the operation of each magnetic source 25. In this embodiment, the closed-loop stepper driver 53 is a PD42S1 model, which includes a stepper motor and transmits signals via a CAN bus.

[0054] Example of working method of indoor magnetic navigation verification system: The following is combined Figure 7 and Figure 8 This invention describes the working method of the indoor magnetic navigation verification system. Before conducting the experiment, it is first necessary to set the target magnetic field environment for the experiment, that is, to generate and modulate the magnetic field. See also... Figure 7 The magnetic field generation and modulation process first executes step S11, where the user selects a preset magnetic field map on the human-computer interaction terminal. Therefore, the human-computer interaction terminal of the indoor magnetic navigation verification system will acquire the magnetic field map selected by the user. Alternatively, the target magnetic field environment and the carrier's trajectory input by the user can be acquired according to experimental requirements, i.e., the target trajectory of the moving carrier.

[0055] Then, step S12 is executed. The host computer solves the target control parameters of each magnetic source according to the target magnetic field environment, layout of the magnetic source array and motion constraints set in step S11, including the rotation angle of the permanent magnet of each magnetic source in two rotation directions and the magnetic field strength that each magnetic source needs to generate.

[0056] Next, the host computer executes step S13, sending magnetic source control signals to the magnetic source array via the CAN bus. These signals include control signals for the rotation angle of each magnetic source and control signals for the magnetic field strength generated by the permanent magnets of each source. Then, step S14 is executed, where each magnetic source drives two sets of drive mechanisms to move according to the received signals, thereby driving the pose changes of the permanent magnets in each source and achieving attitude adjustment. Next, step S15 is executed, where each permanent magnet generates a corresponding magnetic field under the control of the magnetic source control signals. The magnetic fields generated by each source are superimposed to form the target magnetic field, thus creating the target magnetic field environment required for the experiment on the carrier's operating layer.

[0057] Then, step S16 is executed. The mobile carrier moves within the working area according to the target trajectory. Simultaneously, a magnetic field sensor mounted on the mobile carrier collects magnetic field signals, and an inertial sensor collects inertial data during the mobile carrier's operation. The collected data is then transmitted to the edge computer. The edge computer processes the collected data in real time, performing magnetic navigation and magnetic field compensation calculations, and outputs the estimated position, attitude, estimated trajectory, and compensated magnetic field information of the mobile carrier. At the same time, the optical positioning system collects the actual trajectory of the mobile carrier in real time, thus forming the true trajectory.

[0058] Finally, the host computer sends the estimated trajectory and the actual trajectory to the human-computer interaction terminal, which displays the estimated trajectory and the actual trajectory. Furthermore, the host computer or the human-computer interaction terminal executes step S17 to compare and analyze the estimated trajectory and the actual trajectory, obtaining evaluation results such as magnetic field construction deviation, trajectory deviation, repeatability, and compensation effect. These evaluation results can be displayed through the human-computer interaction terminal.

[0059] See Figure 8 When using the application verification system for verification, in the preparation and execution phase, step S21 is executed first, where the user selects the experimental scenario and sets the target trajectory of the mobile carrier, for example, by inputting the target magnetic field environment to be set through a human-computer interaction terminal. Then, step S22 is executed, where the host computer controls the magnetic source array to operate, causing each magnetic source in the array to rotate in the set direction and generate a corresponding magnetic field, thereby forming the target magnetic field environment on the experimental platform. Next, step S23 is executed, where the mobile carrier collects magnetic field strength and inertial data, and runs on the experimental platform according to a pre-set navigation algorithm.

[0060] During the data acquisition and algorithm operation phase, on the one hand, step S24 is executed, where sensors set on the mobile carrier collect magnetic field data and inertial data in real time, and encoders and other devices collect motion state data of the mobile carrier itself. On the other hand, step S25 is executed, where the mobile carrier is driven to move based on a navigation algorithm. On the other hand, step S26 is executed, where the optical positioning system collects the actual trajectory of the mobile carrier.

[0061] During the evaluation and demonstration phase, on one hand, the optical positioning system calculates the true trajectory of the mobile vehicle based on the acquired images and sends the true trajectory to the host computer. Simultaneously, the edge computer also sends the estimated trajectory of the mobile vehicle to the host computer. The host computer executes step S27, comparing the estimated trajectory with the true trajectory to complete the truth comparison and quantitative evaluation. On the other hand, the host computer sends the estimated trajectory, the true trajectory, and the results of the comparative analysis to the human-machine interface terminal. The human-machine interface terminal executes step S28, performing tasks such as trajectory display, map rendering, and mobile vehicle status monitoring. This allows users to intuitively understand the difference between the actual operating status of the mobile vehicle and the estimated operating status, and thereby analyze any problems with the mobile vehicle's hardware or the navigation algorithm software it uses.

[0062] It is evident that the verification system and method of this invention possess both repeatable and quantifiable verification capabilities. Repeatable verification refers to the ability to repeatedly conduct experiments and compare the consistency of results across different rounds under the same target magnetic field environment, the same magnetic source control parameters, the same carrier trajectory, and the same algorithm version. Quantifiable verification refers to the verification system's ability to simultaneously obtain the target magnetic field, the measured magnetic field, the estimated trajectory, and the actual trajectory, and to generate error indices based on these. Quantifiable indices include the deviation between the target magnetic field and the measured magnetic field, the deviation between the estimated trajectory and the actual trajectory, the degree of dispersion between repeated experiments, and the change in error before and after magnetic compensation.

[0063] As can be seen, the verification method of this invention can construct an adjustable and repeatable target magnetic field environment within the same experimental platform, avoiding the problem that simple fixed magnetic source schemes cannot cover multi-condition verification. Furthermore, it can collect magnetic field, attitude, and motion information under dynamic operating conditions of a mobile carrier and synchronously compare it with the actual trajectory, more closely resembling the actual application state. In addition, this invention can verify magnetic field map acquisition, magnetic navigation, and platform magnetic interference compensation in a unified link, which is beneficial for observing the coupling effects between modules and improving the completeness of experimental conclusions. Moreover, this invention has a unified control link and result display link, facilitating repeated experiments, batch experiments, and subsequent algorithm iterations. Finally, in the verification system of this invention, the structure and control architecture of the experimental platform have good scalability, adaptable to different numbers of magnetic sources, different carrier configurations, and different optical positioning schemes.

[0064] Of course, the above embodiments are merely preferred embodiments of the present invention. In other embodiments, the present invention can have many variations. For example, in terms of the optical positioning system, in addition to using an imaging device for imaging, a motion capture system, a UWB positioning system, or a combination of multiple positioning methods can also be used to achieve the acquisition of the real trajectory. In terms of edge computing devices, in addition to using Jetson Orin NX devices, NUCs or other embedded computing platforms with corresponding computing power can also be used. In terms of the magnetic source array, the number of magnetic sources is not limited to 9 and can be expanded or reduced according to the size of the working area, the complexity of the target magnetic field, and the control accuracy requirements; the single-bus CAN control structure can also be expanded into a multi-branch control structure. In terms of the experimental platform, the third-layer scene carrying layer can be replaced with other theme scenes, or the scene layout can be canceled and a pure experimental working surface can be used. In terms of algorithm application, in addition to being applicable to the verification of magnetic navigation algorithms, the present invention can also be used for the comparative verification of platform magnetic interference compensation, multi-sensor fusion positioning, magnetic map acquisition methods, and magnetic field construction methods.

[0065] Finally, it should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An indoor magnetic navigation verification system, characterized in that, include: The experimental platform comprises, from bottom to top, a support layer, a magnetic source deployment layer, a scene support layer, and a carrier operation layer. The magnetic source deployment layer contains a magnetic source array capable of receiving magnetic source control signals sent by a host computer. The magnetic source array includes multiple magnetic sources, each generating a corresponding magnetic field according to the magnetic source control signal. A mobile carrier runs on the carrier operation layer. An edge computer acquires the motion data of the mobile carrier and outputs it to the host computer, which then calculates the estimated trajectory of the mobile carrier. An optical positioning system includes multiple camera devices for acquiring the real trajectory of the moving vehicle; The terminal displays the actual trajectory output by the optical positioning system and compares and displays the estimated trajectory with the actual trajectory.

2. The indoor magnetic navigation verification system according to claim 1, characterized in that: Each of the magnetic sources includes a permanent magnet and a driving unit, the driving unit driving the permanent magnet to rotate in at least two directions.

3. The indoor magnetic navigation verification system of claim 2, wherein, Also includes: The drive unit includes at least two sets of drive mechanisms, each set of drive mechanisms being used to drive the permanent magnet to rotate in one direction; At least two directions are perpendicular to each other.

4. The indoor magnetic navigation verification system of claim 2, wherein, Also includes: Multiple magnetic sources are arranged in an array on the magnetic source deployment layer.

5. The indoor magnetic navigation verification system according to any one of claims 1 to 4, characterized in that: The edge computer is mounted on the mobile carrier, which is also equipped with a magnetic field sensor and an inertial sensor.

6. The indoor magnetic navigation verification system according to claim 5, characterized in that: When the mobile carrier sends motion data to the host computer, it also sends the data collected by the magnetic field sensor and the inertial sensor to the host computer.

7. The indoor magnetic navigation verification system according to any one of claims 1 to 4, characterized in that: The scene carrying layer is arranged with two or more micro-terrain models.

8. The method of operating an indoor magnetic navigation verification system of any one of claims 1 to 7, wherein, include: Define the target magnetic field environment and the target trajectory of the mobile carrier; The host computer sends a magnetic source control signal to the magnetic source array according to the target magnetic field environment, so that each magnetic source generates a corresponding magnetic field according to the magnetic source control signal. The mobile carrier moves according to the target trajectory and collects motion data, which is then output to the host computer. The host computer calculates the estimated trajectory of the mobile carrier. The optical positioning system acquires the true trajectory of the mobile carrier; The terminal displays the actual trajectory output by the optical positioning system and compares and displays the estimated trajectory with the actual trajectory.

9. The working method of the indoor magnetic navigation verification system according to claim 8, characterized in that: After each magnetic source receives the magnetic source control signal, the permanent magnet on the magnetic source rotates in at least two directions to change the position of the permanent magnet and generate a magnetic field of a preset magnetic field strength.

10. The working method of the indoor magnetic navigation verification system according to claim 8 or 9, characterized in that: When the mobile carrier moves along the target trajectory, it moves along the target trajectory based on the magnetic field signal collected by the magnetic field sensor and the preset navigation algorithm.

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