CN113720326A - Magnetic beacon calibration method, device and system based on magnetic field intensity characteristics - Google Patents
Magnetic beacon calibration method, device and system based on magnetic field intensity characteristics Download PDFInfo
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Abstract
The invention provides a magnetic beacon calibration method, device and system based on magnetic field intensity characteristics, and relates to the technical field of magnetic beacons. The magnetic beacon calibration method based on the magnetic field intensity characteristics comprises the following steps: energizing a first solenoid of a dual-axis magnetic beacon to generate a spatial magnetic field; collecting magnetic field intensity data through a magnetic sensor, or collecting induced voltage data of a moving conductor through a voltage sensor; performing exponential smoothing on the magnetic field strength data or the induced voltage data, drawing a derivative image according to the smoothed magnetic field strength data or the smoothed induced voltage data, and judging a central point of the first solenoid according to the derivative image; determining a center point of the second solenoid; determining a center position of the dual-axis magnetic beacon. According to the technical scheme, the magnetic beacon is calibrated by using the derivative rule of the magnetic field with respect to the distance, so that the calibration precision is ensured, the calibration cost and time are saved, and the positioning efficiency of the low-frequency magnetic beacon is effectively improved.
Description
Technical Field
The invention relates to the technical field of magnetic beacons, in particular to a magnetic beacon calibration method, device and system based on magnetic field intensity characteristics.
Background
At present, the calibration method of the magnetic beacon center mainly includes the following two methods: the first method is to measure the size of the magnetic beacon directly, and take the center position as the center of the magnetic beacon, however, the calibration precision is affected by the measuring means and the manufacturing process of the magnetic beacon; the second method is to measure multiple groups of data at different positions by using the magnetic sensor, each group of magnetic field intensity data can obtain a group of distances, and then the position of the center of the magnetic beacon can be obtained by solving a nonlinear equation set, however, the calibration precision is influenced by the precision of the magnetic sensor and the quantity of the measured data.
Disclosure of Invention
The invention solves the problem of how to improve the calibration precision and the calibration efficiency of the magnetic beacon.
In order to solve the above problems, the present invention provides a magnetic beacon calibration method based on magnetic field strength characteristics, including: energizing a first solenoid of a dual-axis magnetic beacon to generate a spatial magnetic field; collecting magnetic field intensity data through a magnetic sensor, or collecting induced voltage data of a moving conductor through a voltage sensor; performing exponential smoothing on the magnetic field strength data or the induced voltage data, drawing a derivative image according to the smoothed magnetic field strength data or the smoothed induced voltage data, and judging a central point of the first solenoid according to the derivative image; repeating the above operations for a second solenoid of the dual-axis magnetic beacon, determining a center point of the second solenoid; determining a center position of the dual-axis magnetic beacon from a center point of the first solenoid and a center point of the second solenoid.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the magnetic beacon is calibrated by using the derivative rule of the magnetic field with respect to the distance, the magnetic beacon can be calibrated only by the moving conductor and the sensor, the calibration precision is guaranteed, the calibration cost and time are saved, and the positioning efficiency of the low-frequency magnetic beacon is effectively improved.
Optionally, exciting the first solenoid of the dual-axis magnetic beacon to generate a spatial magnetic field comprises: and introducing the constant direct current signal amplified by the linear power amplifier into the first solenoid, so that the first solenoid generates a constant and invariable magnetic field in the space.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the constant direct current signal amplified by the linear power amplifier is introduced into the first solenoid to excite the first solenoid, so that a constant magnetic field is generated, and the central point of the first solenoid can be accurately determined.
Optionally, the acquiring magnetic field intensity data by a magnetic sensor, or acquiring induced voltage data of a moving conductor by a voltage sensor comprises: the magnetic sensor which moves at a constant speed in a fixed direction is used for collecting magnetic field intensity data, or the conductor is arranged to move along the direction vertical to the axial direction of the solenoid to cut a magnetic induction line, and the voltage sensor is used for collecting induced voltage data generated at two ends of the conductor.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the magnetic field intensity data are collected through the magnetic sensor, or the induced voltage data generated by cutting two ends of the magnetic induction line conductor are collected through the voltage sensor, so that the derivative image can be accurately drawn to complete the magnetic beacon calibration.
Optionally, the exponentially smoothing the magnetic field strength data or the induced voltage data comprises: and dynamically adjusting a smoothing coefficient according to the prediction error of the exponential smoothing by adopting a self-adaptive exponential smoothing method.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the smoothing coefficient is dynamically adjusted according to the prediction error of exponential smoothing by adopting the self-adaptive exponential smoothing method, so that errors caused by inappropriate selection of the smoothing coefficient are effectively avoided, and the accuracy of magnetic beacon calibration is improved.
Optionally, the determining the center point of the first solenoid from the derivative image comprises: determining a point where the magnetic field strength is zero and located at a peak position in the derivative image as a center point of the first solenoid, or determining a point where the magnetic field strength is peak and located at a zero position in the derivative image as a center point of the first solenoid.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the central point of the first solenoid is determined through the derivative image, the cost and time of magnetic beacon calibration are effectively reduced, and the efficiency of low-frequency magnetic beacon positioning is effectively improved.
Optionally, the determining the center position of the dual-axis magnetic beacon from the center point of the first solenoid and the center point of the second solenoid comprises: determining a first offset of the first solenoid in a first direction according to a center point of the first solenoid, determining a second offset of the second solenoid in a second direction according to a center point of the second solenoid, and determining a center position of the dual-axis magnetic beacon according to the first offset and the second offset.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the center position of the dual-axis magnetic beacon is determined according to the first offset of the first solenoid in the first direction and the second offset of the second solenoid in the second direction, and the calibration of the dual-axis magnetic beacon is achieved.
Optionally, the dual-axis magnetic beacon is calibrated in a magnetic shielded room.
According to the magnetic beacon calibration method based on the magnetic field intensity characteristics, the biaxial magnetic beacon is arranged for calibration in the magnetic shielding room, so that the interference of the geomagnetic field and the power frequency magnetic field to the calibration is effectively prevented, and the accuracy of the magnetic beacon calibration is further improved.
The invention also provides a magnetic beacon calibration device based on the magnetic field intensity characteristics, which comprises: the excitation module is used for exciting a first solenoid of the biaxial magnetic beacon to generate a space magnetic field; the acquisition module is used for acquiring magnetic field intensity data through the magnetic sensor or acquiring induced voltage data of the moving conductor through the voltage sensor; the first judgment module is used for performing exponential smoothing on the magnetic field intensity data or the induction voltage data, drawing a derivative image according to the smoothed magnetic field intensity data or the induction voltage data, and judging a central point of the first solenoid according to the derivative image; the second judgment module is used for repeating the operation on a second solenoid of the biaxial magnetic beacon and determining the central point of the second solenoid; and the calibration module is used for determining the central position of the dual-axis magnetic beacon according to the central point of the first solenoid and the central point of the second solenoid. Compared with the prior art, the magnetic beacon calibration device based on the magnetic field strength characteristic and the magnetic beacon calibration method based on the magnetic field strength characteristic have the same advantages, and are not repeated herein.
The invention also provides a magnetic beacon calibration system based on the magnetic field strength characteristics, which comprises a computer readable storage medium and a processor, wherein the computer readable storage medium stores a computer program, and the computer program is read by the processor and runs to realize the magnetic beacon calibration method based on the magnetic field strength characteristics. Compared with the prior art, the magnetic beacon calibration system based on the magnetic field strength characteristic and the magnetic beacon calibration method based on the magnetic field strength characteristic have the same advantages, and are not repeated herein.
The present invention also provides a computer-readable storage medium, which stores a computer program, and when the computer program is read and executed by a processor, the method for calibrating a magnetic beacon based on the magnetic field strength characteristics as above is implemented. The computer readable storage medium has the same advantages as the magnetic beacon calibration method based on the magnetic field intensity characteristics compared with the prior art, and is not described herein again.
Drawings
FIG. 1 is a flow chart of a magnetic beacon calibration method based on magnetic field strength characteristics according to an embodiment of the present invention;
FIG. 2 is a block diagram of a single magnetic dipole in accordance with an embodiment of the present invention;
FIG. 3 is a schematic diagram of data collection during calibration according to an embodiment of the present invention;
FIG. 4 shows the magnetic induction B under ideal conditions according to the embodiment of the present inventionxA change image with respect to the distance l;
FIG. 5 shows the magnetic induction B under ideal conditions according to the embodiment of the present inventionzA change image with respect to the distance l;
FIG. 6 is an image of the derivative change of magnetic induction with respect to distance l under ideal conditions according to an embodiment of the present invention;
FIG. 7 is a diagram of a solenoid generated magnetic field distribution simulation in accordance with an embodiment of the present invention;
FIG. 8 shows the smoothed magnetic field strength B of an embodiment of the inventionxImage sum
An image;
FIG. 9 shows the smoothed magnetic field strength B of an embodiment of the inventionzImage sum
And (4) an image.
Detailed Description
Scientific development brings the production and life of human beings with the change of day and night, and the space that human beings can explore is also bigger and bigger simultaneously, and the current location demand of human is difficult to satisfy to current positioning means of current. The traditional means such as GPS navigation positioning, radio navigation positioning and the like have lower position precision in indoor, underground tunnels, caves and the like and are easy to lose effectiveness; inertial navigation has accumulated errors, and it is difficult to provide high-precision services for a long time. The low-frequency magnetic beacon positioning technology has strong penetrability and low power consumption, and can realize high-precision positioning service in underground scenes or indoor scenes with failure of GPS positioning and radio positioning. In order to ensure the accuracy of the magnetic beacon positioning and reduce the error generated by the magnetic beacon positioning as much as possible, it is important to determine the central position of the magnetic beacon.
At present, the calibration method of the magnetic beacon center mainly includes the following two methods: the first method is to measure the size of the magnetic beacon directly, take the central position as the center of the magnetic beacon, the calibration precision is influenced by the measuring means and the manufacturing process of the magnetic beacon; the second method is that a magnetic sensor is used for measuring a plurality of groups of data at different positions, each group of magnetic field intensity data can obtain a group of distances, and then the position of the center of the magnetic beacon can be obtained by solving a nonlinear equation set, and the calibration precision is influenced by the precision of the magnetic sensor and the quantity of the measured data. Therefore, the invention utilizes the single magnetic dipole model and the Faraday electromagnetic induction law to calibrate the magnetic beacon and provides the magnetic beacon calibration method based on the magnetic field intensity characteristic.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
As shown in fig. 1, an embodiment of the present invention provides a magnetic beacon calibration method based on magnetic field strength characteristics, including: energizing a first solenoid of a dual-axis magnetic beacon to generate a spatial magnetic field; collecting magnetic field intensity data through a magnetic sensor, or collecting induced voltage data of a moving conductor through a voltage sensor; performing exponential smoothing on the magnetic field strength data or the induced voltage data, drawing a derivative image according to the smoothed magnetic field strength data or the smoothed induced voltage data, and judging a central point of the first solenoid according to the derivative image; repeating the above operations for a second solenoid of the dual-axis magnetic beacon, determining a center point of the second solenoid; determining a center position of the dual-axis magnetic beacon from a center point of the first solenoid and a center point of the second solenoid.
Specifically, in this embodiment, the magnetic beacon calibration method based on the magnetic field strength characteristics includes:
a first solenoid of the biaxial magnetic beacon is excited to generate a space magnetic field, and a constant direct current signal amplified by a linear power amplifier can be introduced into the solenoid, so that the solenoid generates a constant magnetic field in the space.
Collecting magnetic field intensity data through a magnetic sensor, or collecting induced voltage data of a moving conductor through a voltage sensor; the moving magnetic sensor or conductor can be moved along the direction perpendicular to the axial direction of the solenoid, and the magnetic signal or voltage signal collected by the sensor is transmitted to the device, so as to find the corresponding central point of the solenoid, and the specific process is as follows:
1. according to the magnetic dipole theory, the magnetic field vector generated by a single magnetic dipole can be expressed as:
the generated magnetic field of any solenoid in the magnetic beacon at the measuring point is shown as formula (1) in combination with the model diagram of a single magnetic dipole shown in fig. 2, wherein P is the target point and P is the target point*Is the projection of a point P on an xy plane, Q is a current infinitesimal, mu is a magnetic field propagation medium factor, I is the size of an exciting current, R is the equivalent magnetic dipole radius, R is the distance between a target point and a magnetic dipole, theta is the yaw angle between the magnetic dipole and the target point relative to an x axis,
the pitch angle between the magnetic dipole and the target point with respect to the x-axis, phi denotes the angle between OQ and the direction of the x-axis,
representing the vector of the current infinitesimal Q with respect to the target point P.
2. As shown in connection with fig. 3, when the magnetic sensor is moved in the manner shown in fig. 3, the pitch angle
The distance r between the center of the solenoid and the conductor, the moving distance l of the conductor and the perpendicular distance h between the center of the solenoid and the moving path of the conductor have the following geometrical relations:
3. by substituting equations (2) and (3) for equation (1), the relationship between the magnetic sensor moving distance and the magnetic induction intensity can be obtained as follows:
and (4) drawing a change image of the magnetic induction intensity relative to the distance l. As shown in fig. 4 and 5, the magnetic field intensity component B x0 at the center point, the rate of change is maximum; b iszThe value is maximum at the center point and the rate of change is 0.
4. If the conductor is used for cutting the magnetic induction lines, the Faraday's law of electromagnetic induction needs to be considered. When the moving conductor cuts the magnetic field generated by the solenoid, the induced voltage generated by the solenoid has the following relationship:
where S is the cross-sectional area of the moving conductor, v is the moving speed of the conductor, and l is the distance the conductor moves. From the equation (5), when the conductor is in a uniform motion state, the generated induced voltage and the derivative of the magnetic induction intensity with respect to the distance have the same variation trend, that is, the center of the solenoid can be judged by the variation of the derivative of the induced voltage. If the conductor moves in a direction perpendicular to the axis of the magnetic beacon, only the cut B will be made, as shown in connection with FIG. 3zThe magnetic induction component of the direction.
And performing exponential smoothing on the magnetic field intensity data or the induced voltage data, drawing a derivative image according to the smoothed magnetic field intensity data or the smoothed induced voltage data, and judging the central point of the first solenoid according to the derivative image. Because the magnetic induction intensity measurement has interference, the fluctuation is large, and the derivation work is not favorable, the data smoothing is needed to be carried out on the magnetic induction intensity measurement, and then the derivation calculation is carried out. The data quantity required by exponential smoothing is small, the recent data is considered, the long-term data is not abandoned, and meanwhile, the weight of the data far away in time is gradually converged to zero by controlling the weight change. However, the coefficient selection of the exponential smoothing is often more subjective, and the adoption of the adaptive exponential smoothing can dynamically adjust the smoothing coefficient according to the prediction error of the exponential smoothing, so that the error caused by the improper selection of the smoothing coefficient can be effectively avoided.
By deriving the conductor movement distance l from equation (4), the following equation can be obtained:
it can also be seen from equation (6) and fig. 6 drawn according to equation (6) that the magnetic induction B is when the conductor is located at the center of the magnetic fieldzThe derivative of the moving distance l relative to the conductor is 0, and the derivative is not 0 at other positions; magnetic induction BxThe derivative value with respect to the conductor displacement distance l is minimal. Therefore, the data after exponential smoothing is derived according to the formula (6) to obtain the magnetic induction intensity BxOr BzAn image of the conductor movement distance l and an image of the derivative of the magnetic induction with respect to the conductor movement distance l. Analysis by Synthesis BxThe point where the slope of the image is maximum and
minimum point of image value or BzSlope minimum sum of points of image
The point where the image value is 0 can be calibrated to obtain the center position of the solenoid.
The above operation is repeated for the second solenoid of the dual-axis magnetic beacon, and the center point of the second solenoid is determined.
The center position of the dual-axis magnetic beacon is determined from the center point of the first solenoid and the center point of the second solenoid. Calibrating the center position of a first solenoid to obtain the offset of the first solenoid on the x axis; and calibrating the central position of the second solenoid to obtain the offset of the second solenoid on the y axis, and synthesizing the two offsets to know the central position of the magnetic beacon.
The following provides a simulation verification example.
Simulation verification example 1: magnetic field simulation verification is generated for the energized solenoid. The magnetic induction distribution diagram shown in fig. 7 (the magnetic field components of the x-axis, the y-axis, and the z-axis from top to bottom) can be obtained by simulating the magnetic field generated by the solenoid by using COMSOL. As can be seen from fig. 7, the distribution of the magnetic field generated by the solenoid is substantially the same as the theoretical analysis of equation (4) and fig. 4 and 5.
Simulation verification example 2: and carrying out simulation verification on the magnetic beacon calibration method based on the magnetic field intensity characteristics. A 30 turn solenoid was simulated using COMSOL with its axis coincident on the z-axis of the coordinate system and its center coincident on the origin. Magnetic field data is then collected over the solenoid in a direction perpendicular to the yOz plane, and the magnetic field data is collected. The measured data is exponentially smoothed and derived, and the resulting image and calibration position are shown in fig. 8 and 9. Since the system in the simulation has some errors, it can be seen from the results that the calibrated center positions are respectively 2.592mm and 2.551mm, which are relatively close to each other. The invention has the advantages of small error, high precision, reduced calibration difficulty and improved magnetic beacon calibration efficiency.
In the embodiment, the magnetic beacon is calibrated by using the derivative rule of the magnetic field about the distance, the calibration of the magnetic beacon can be realized only by the moving conductor and the sensor, the calibration cost and time are saved while the calibration precision is ensured, and the positioning efficiency of the low-frequency magnetic beacon is effectively improved.
Optionally, exciting the first solenoid of the dual-axis magnetic beacon to generate a spatial magnetic field comprises: and introducing the constant direct current signal amplified by the linear power amplifier into the first solenoid, so that the first solenoid generates a constant and invariable magnetic field in the space.
Specifically, in the present embodiment, energizing the first solenoid of the dual-axis magnetic beacon to generate the spatial magnetic field comprises: the constant direct current signal amplified by the linear power amplifier is fed into the first solenoid, so that the first solenoid generates a constant magnetic field in the space. Accordingly, the energization of the second solenoid may also be performed in the manner described above.
In the embodiment, the first solenoid is excited by introducing a constant direct current signal amplified by the linear power amplifier into the first solenoid, so that a constant magnetic field is generated and the central point of the first solenoid can be accurately determined.
Optionally, the acquiring magnetic field intensity data by a magnetic sensor, or acquiring induced voltage data of a moving conductor by a voltage sensor comprises: the magnetic sensor which moves at a constant speed in a fixed direction is used for collecting magnetic field intensity data, or the conductor is arranged to move along the direction vertical to the axial direction of the solenoid to cut a magnetic induction line, and the voltage sensor is used for collecting induced voltage data generated at two ends of the conductor.
Specifically, in this embodiment, acquiring magnetic field strength data by the magnetic sensor or acquiring induced voltage data of the moving conductor by the voltage sensor includes: the magnetic sensor is used for moving near the solenoid at a constant speed in a fixed direction to acquire data, or the conductor is used for moving above the solenoid at a constant speed, and the sensor is used for acquiring induced voltage generated at two ends of the conductor.
In the embodiment, magnetic field intensity data is collected through a magnetic sensor, or induced voltage data generated at two ends of a cut magnetic induction line conductor is collected through a voltage sensor, so that a derivative image can be accurately drawn to complete magnetic beacon calibration.
Optionally, the exponentially smoothing the magnetic field strength data or the induced voltage data comprises: and dynamically adjusting a smoothing coefficient according to the prediction error of the exponential smoothing by adopting a self-adaptive exponential smoothing method.
Specifically, in the present embodiment, exponentially smoothing the magnetic field intensity data or the induced voltage data includes: and dynamically adjusting a smoothing coefficient according to the prediction error of the exponential smoothing by adopting a self-adaptive exponential smoothing method. Defining y (t) as a magnetic induction intensity data measured value (or a voltage measured value) at the time t, e (t) as a smooth prediction error at the time t, Y (t) as a magnetic induction intensity predicted value (or a voltage measured value) after smoothing at the time t, E (t) as a smooth prediction error weighted average at the time t, p as a weighting coefficient, M (t) as an absolute smoothing error at the time t, and alpha as an exponential smoothing coefficient, wherein the specific process of the self-adaptive exponential smoothing method comprises the following steps: reading data; giving an initial value; firstly, calculating the error between a predicted value and a measured value; then, the prediction error E (t) at the moment and the weighted average prediction error E (t-1) at the previous moment are used for carrying out weighted average again to obtain the weighted average prediction error E (t) at the moment so as to ensure that the error data at the previous moment can be used as much as possible in the smoothing process; meanwhile, the absolute smoothing error M (t) (p | e (t) | + (1-p) M (t-1) is calculated by weighted average according to the prediction error e (t) so as to dynamically adjust the weighting coefficient in the next step.
Wherein the exponential smoothing coefficient
Alpha belongs to (0,1), when alpha approaches to 0, the smaller the error of E (t), the more accurate the predicted value is, and the closer the smoothed data is to the predicted value; as α approaches 1, the greater the error in e (t), the more accurate the measurement data, and the closer the smoothed data is to the measured value. By weighting, a suitable predictor is found.
In the embodiment, the self-adaptive exponential smoothing method is adopted to dynamically adjust the smoothing coefficient according to the prediction error of exponential smoothing, so that the error caused by improper selection of the smoothing coefficient is effectively avoided, and the calibration accuracy of the magnetic beacon is further improved.
Optionally, the determining the center point of the first solenoid from the derivative image comprises: determining a point where the magnetic field strength is zero and located at a peak position in the derivative image as a center point of the first solenoid, or determining a point where the magnetic field strength is peak and located at a zero position in the derivative image as a center point of the first solenoid.
Specifically, in the present embodiment, analysis B is shown in conjunction with fig. 6xThe point where the slope of the image is maximum and
minimum point of image value or BzSlope minimum sum of points of image
The point where the image value is 0 can be calibrated to obtain the center position of the solenoid.
In the embodiment, the central point of the first solenoid is determined through the derivative image, so that the cost and time for calibrating the magnetic beacon are effectively reduced, and the efficiency for positioning the low-frequency magnetic beacon is effectively improved.
Optionally, the determining the center position of the dual-axis magnetic beacon from the center point of the first solenoid and the center point of the second solenoid comprises: determining a first offset of the first solenoid in a first direction according to a center point of the first solenoid, determining a second offset of the second solenoid in a second direction according to a center point of the second solenoid, and determining a center position of the dual-axis magnetic beacon according to the first offset and the second offset.
Specifically, in the present embodiment, determining the center position of the two-axis magnetic beacon from the center point of the first solenoid and the center point of the second solenoid includes: a first offset amount of the first solenoid in the first direction is determined according to a center point of the first solenoid, a second offset amount of the second solenoid in the second direction is determined according to a center point of the second solenoid, and a center position of the dual-axis magnetic beacon is determined according to the first offset amount and the second offset amount. For example, if the first offset amount of the first solenoid on the x-axis is 1 and the second offset amount of the second solenoid on the y-axis is 1, the center position of the resulting two-axis magnetic beacon is (1, 1).
In the embodiment, the center position of the dual-axis magnetic beacon is determined according to the first offset of the first solenoid in the first direction and the second offset of the second solenoid in the second direction, and the calibration of the dual-axis magnetic beacon is realized.
Optionally, the dual-axis magnetic beacon is calibrated in a magnetic shielded room.
Specifically, in this embodiment, in order to prevent the interference of the geomagnetic field and the power frequency magnetic field to the calibration, the calibration of the biaxial magnetic beacon is performed in a magnetic shielding room.
In this embodiment, through setting up biax magnetic beacon and demarcating in the magnetic screen room, effectively prevent that geomagnetic field and power frequency magnetic field from causing the interference to demarcating, and then improve the accuracy that magnetic beacon demarcated.
Another embodiment of the present invention provides a magnetic beacon calibration apparatus based on magnetic field strength characteristics, including: the excitation module is used for exciting a first solenoid of the biaxial magnetic beacon to generate a space magnetic field; the acquisition module is used for acquiring magnetic field intensity data through the magnetic sensor or acquiring induced voltage data of the moving conductor through the voltage sensor; the first judgment module is used for performing exponential smoothing on the magnetic field intensity data or the induction voltage data, drawing a derivative image according to the smoothed magnetic field intensity data or the induction voltage data, and judging a central point of the first solenoid according to the derivative image; the second judgment module is used for repeating the operation on a second solenoid of the biaxial magnetic beacon and determining the central point of the second solenoid; and the calibration module is used for determining the central position of the dual-axis magnetic beacon according to the central point of the first solenoid and the central point of the second solenoid.
Another embodiment of the present invention provides a magnetic beacon calibration system based on magnetic field strength characteristics, which includes a computer-readable storage medium storing a computer program and a processor, where the computer program is read by the processor and executed to implement the above magnetic beacon calibration method based on magnetic field strength characteristics.
Another embodiment of the present invention provides a computer-readable storage medium, which stores a computer program, and when the computer program is read and executed by a processor, the computer program implements the magnetic beacon calibration method based on the magnetic field strength characteristic as described above.
Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.
Claims (10)
1. A magnetic beacon calibration method based on magnetic field intensity characteristics is characterized by comprising the following steps:
energizing a first solenoid of a dual-axis magnetic beacon to generate a spatial magnetic field;
collecting magnetic field intensity data through a magnetic sensor, or collecting induced voltage data of a moving conductor through a voltage sensor;
performing exponential smoothing on the magnetic field strength data or the induced voltage data, drawing a derivative image according to the smoothed magnetic field strength data or the smoothed induced voltage data, and judging a central point of the first solenoid according to the derivative image;
repeating the above operations for a second solenoid of the dual-axis magnetic beacon, determining a center point of the second solenoid;
determining a center position of the dual-axis magnetic beacon from a center point of the first solenoid and a center point of the second solenoid.
2. A method for magnetic beacon calibration based on magnetic field strength characteristics according to claim 1, wherein exciting the first solenoid of the dual-axis magnetic beacon to generate a spatial magnetic field comprises:
and introducing the constant direct current signal amplified by the linear power amplifier into the first solenoid, so that the first solenoid generates a constant and invariable magnetic field in the space.
3. A magnetic beacon calibration method based on magnetic field strength characteristics according to claim 1, wherein the collecting magnetic field strength data by a magnetic sensor or collecting induced voltage data of a moving conductor by a voltage sensor comprises:
the magnetic sensor which moves at a constant speed in a fixed direction is used for collecting magnetic field intensity data, or the conductor is arranged to move along the direction vertical to the axial direction of the solenoid to cut a magnetic induction line, and the voltage sensor is used for collecting induced voltage data generated at two ends of the conductor.
4. A method of magnetic beacon calibration based on magnetic field strength characteristics according to claim 1, wherein the exponentially smoothing the magnetic field strength data or the induced voltage data comprises:
and dynamically adjusting a smoothing coefficient according to the prediction error of the exponential smoothing by adopting a self-adaptive exponential smoothing method.
5. A method for magnetic beacon calibration based on magnetic field strength characteristics according to claim 1, wherein said determining the center point of the first solenoid from the derivative image comprises:
determining a point where the magnetic field strength is zero and located at a peak position in the derivative image as a center point of the first solenoid, or determining a point where the magnetic field strength is peak and located at a zero position in the derivative image as a center point of the first solenoid.
6. A method of magnetic beacon calibration based on magnetic field strength characteristics according to claim 1 wherein said determining the center position of said dual-axis magnetic beacon from the center point of said first solenoid and the center point of said second solenoid comprises:
determining a first offset of the first solenoid in a first direction according to a center point of the first solenoid, determining a second offset of the second solenoid in a second direction according to a center point of the second solenoid, and determining a center position of the dual-axis magnetic beacon according to the first offset and the second offset.
7. A magnetic beacon calibration method based on magnetic field strength characteristics according to any one of claims 1 to 6, characterized in that the dual-axis magnetic beacon is calibrated in a magnetic shielding room.
8. A magnetic beacon calibration device based on magnetic field intensity characteristics is characterized by comprising:
the excitation module is used for exciting a first solenoid of the biaxial magnetic beacon to generate a space magnetic field;
the acquisition module is used for acquiring magnetic field intensity data through the magnetic sensor or acquiring induced voltage data of the moving conductor through the voltage sensor;
the first judgment module is used for performing exponential smoothing on the magnetic field intensity data or the induction voltage data, drawing a derivative image according to the smoothed magnetic field intensity data or the induction voltage data, and judging a central point of the first solenoid according to the derivative image;
the second judgment module is used for repeating the operation on a second solenoid of the biaxial magnetic beacon and determining the central point of the second solenoid;
and the calibration module is used for determining the central position of the dual-axis magnetic beacon according to the central point of the first solenoid and the central point of the second solenoid.
9. A magnetic beacon calibration system based on magnetic field strength characteristics, comprising a computer readable storage medium storing a computer program and a processor, wherein the computer program is read by the processor and executed to implement the magnetic beacon calibration method based on magnetic field strength characteristics according to any one of claims 1 to 7.
10. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program, which when read and executed by a processor, implements the magnetic beacon calibration method based on magnetic field strength characteristics according to any one of claims 1 to 7.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106703786A (en) * | 2016-12-13 | 2017-05-24 | 中国地质大学（武汉） | System and method for real-time positioning in horizontal directional drilling on basis of ground magnetic beacon |
| CN108572332A (en) * | 2017-03-08 | 2018-09-25 | 天津工业大学 | Three-dimension reconstruction based on sensor array and calibration system |
| CN108802636A (en) * | 2018-06-12 | 2018-11-13 | 云南电网有限责任公司昆明供电局 | A kind of frequency response curve scaling method, the apparatus and system of magnetic field sensor |
| CN109883415A (en) * | 2019-03-01 | 2019-06-14 | 哈尔滨工业大学 | A kind of rotating excitation field localization method based on trigonometric function fitting |
| CN109917325A (en) * | 2019-04-04 | 2019-06-21 | 哈尔滨工业大学 | A kind of localization method, apparatus and system based on more magnetic beacons |
| CN112393730A (en) * | 2020-11-19 | 2021-02-23 | 哈尔滨工业大学 | Magnetic beacon positioning method and system based on magnetic induction intensity and characteristic vector |
| CN112556683A (en) * | 2020-11-24 | 2021-03-26 | 哈尔滨工业大学（深圳） | Positioning method, device and system based on magnetic dipole field and storage medium |
| CN113108777A (en) * | 2021-04-15 | 2021-07-13 | 哈尔滨工业大学 | Single anchor positioning method based on magnetic beacon |
-
2021
- 2021-09-02 CN CN202111026387.4A patent/CN113720326B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106703786A (en) * | 2016-12-13 | 2017-05-24 | 中国地质大学（武汉） | System and method for real-time positioning in horizontal directional drilling on basis of ground magnetic beacon |
| CN108572332A (en) * | 2017-03-08 | 2018-09-25 | 天津工业大学 | Three-dimension reconstruction based on sensor array and calibration system |
| CN108802636A (en) * | 2018-06-12 | 2018-11-13 | 云南电网有限责任公司昆明供电局 | A kind of frequency response curve scaling method, the apparatus and system of magnetic field sensor |
| CN109883415A (en) * | 2019-03-01 | 2019-06-14 | 哈尔滨工业大学 | A kind of rotating excitation field localization method based on trigonometric function fitting |
| CN109917325A (en) * | 2019-04-04 | 2019-06-21 | 哈尔滨工业大学 | A kind of localization method, apparatus and system based on more magnetic beacons |
| CN112393730A (en) * | 2020-11-19 | 2021-02-23 | 哈尔滨工业大学 | Magnetic beacon positioning method and system based on magnetic induction intensity and characteristic vector |
| CN112556683A (en) * | 2020-11-24 | 2021-03-26 | 哈尔滨工业大学（深圳） | Positioning method, device and system based on magnetic dipole field and storage medium |
| CN113108777A (en) * | 2021-04-15 | 2021-07-13 | 哈尔滨工业大学 | Single anchor positioning method based on magnetic beacon |
Non-Patent Citations (5)
| Title |
|---|
| QINGHUA LI: "Quick orientation of rotary magnetic field based on feature vector", PROCEEDINGS OF THE 38TH CHINESE CONTROL CONFERENCE * |
| YU YATING: "Study on the Electromagnetic Properties of Eddy Current Sensor", IEEE * |
| 田俊荣;张松勇;章志涛;: "三端式磁通门技术在空运杂散磁场检测中的运用", 机电设备, no. 1 * |
| 谢阳光: "基于双磁偶极子的螺线管磁场建模分析", 中国惯性技术学报, vol. 27, no. 5 * |
| 郑元勋: "高精度磁信标中心位置与姿态角标定方法", 中国惯性技术学报, vol. 28, no. 3 * |
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