Detector positioning method and system

Abstract

The invention provides a detector positioning method and system, and the method comprises the steps: obtaining first magnetic field signals and spatial positions of a plurality of test points; the first magnetic field signal is a signal of a magnetic field generated by the magnetic field generation unit at a spatial position corresponding to each test point; based on the first magnetic field signal of each test point and in combination with the spatial position of each test point, acquiring magnetic field spatial distribution; and acquiring a second magnetic field signal group on the surface of the to-be-detected detector, and acquiring a spatial state of the to-be-detected detector based on the second magnetic field signal group in combination with the magnetic field spatial distribution so as to position the to-be-detected detector. Positioning is carried out through the magnetic field signal, the influence of a shielding object on the positioning accuracy of the to-be-detected detector can be avoided, the positioning precision of the to-be-detected detector is improved, and therefore the better positioning effect of the to-be-detected detector is achieved.

Description

Technical Field

[0001] The present application belongs to the field of detector technology, and relates to a detector positioning technology, and in particular to a detector positioning method and system. Background Art

[0002] As the core component of a radiographic imaging system, the detector's position within the system directly impacts the magnification, distortion, and spatial resolution of the detected image, ultimately affecting the image quality. Therefore, in practical applications, precise detector positioning is often required to ensure geometric accuracy and consistency in imaging.

[0003] Existing detector positioning methods include visual positioning solutions and radio frequency signal positioning solutions. The visual positioning solution calculates the detector's position by setting optical markers on the detector and capturing images of the detector to triangulate the markers. However, since there may be some obstructions in front of the detector, such as protective devices such as lead plates and lead glass in front of the detector, or tool parts dropped during equipment installation or maintenance, the image acquisition process is easily interfered with by these obstructions, resulting in failure or error in the identification of the markers, which in turn causes large positioning errors. The radio frequency signal positioning solution calculates the detector's position based on the transmission characteristics of the radio frequency signal by deploying multiple radio frequency signal transmitters and receivers. However, when the radio frequency signal encounters an obstruction during transmission, the multipath effect causes the signal to be reflected, refracted, or scattered, which can also cause signal distortion, resulting in low detector positioning accuracy.

[0004] Based on this, how to ensure the accuracy of detector positioning is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a detector positioning method and system for solving the problem in the prior art that both visual positioning solutions and radio frequency signal positioning solutions are easily affected by obstructions, resulting in errors in detector positioning and low accuracy.

[0006] In the first aspect, the present application provides a detector positioning method, including: obtaining first magnetic field signals and spatial positions of several test points; the first magnetic field signal is a signal of the magnetic field generated by a magnetic field generating unit at the spatial position corresponding to each of the test points; based on the first magnetic field signal of each of the test points, combined with the spatial position of each of the test points, obtaining the spatial distribution of the magnetic field; obtaining a second magnetic field signal group on the surface of the detector to be tested, and based on the second magnetic field signal group, combined with the spatial distribution of the magnetic field, obtaining the spatial state of the detector to be tested, so as to position the detector to be tested.

[0007] In one embodiment of the present application, the first magnetic field signal of each of the test points is combined with the spatial position of each of the test points to obtain the magnetic field spatial distribution, including: based on the spatial position of each of the test points and the first magnetic field signal, obtaining the mapping relationship between the first magnetic field signal and the spatial position by a mathematical method as the magnetic field spatial distribution; wherein the mathematical method is any one of an interpolation method, a numerical simulation method or a data fitting method.

[0008] In one embodiment of the present application, each of the test points is located on a plurality of mutually parallel planes, and the spatial distribution of the magnetic field is obtained by a mathematical method based on the spatial position and the first magnetic field signal of each of the test points, including: obtaining the distance between the plane corresponding to each of the test point sets and the magnetic field generating unit as the plane height; performing surface fitting based on the first magnetic field signal and the spatial position corresponding to each test point in each of the test point sets to obtain the magnetic field plane distribution of the plane corresponding to each of the test point sets; and performing deep convolution fitting based on each of the magnetic field plane distributions and the corresponding plane height to obtain the magnetic field spatial distribution.

[0009] In one embodiment of the present application, the spatial state of the detector to be tested includes a spatial position; the second magnetic field signal group includes a magnetic field signal of at least one characteristic point on the surface of the detector to be tested; wherein, the method of obtaining the spatial position includes: obtaining the magnetic field signal of each characteristic point on the surface of the detector to be tested, and obtaining the spatial position of each characteristic point in combination with the spatial distribution of the magnetic field; based on the spatial position of each characteristic point, determining the spatial position of the detector to be tested.

[0010] In one embodiment of the present application, the magnetic field generating unit emits at least three magnetic field signals of different preset frequencies, and the emission directions of the magnetic field signals of each preset frequency are different and the magnetic field strength is the same; the spatial state of the detector to be tested includes a spatial angle; wherein, the method for obtaining the spatial angle includes: obtaining the emission direction corresponding to each of the magnetic field signals of the preset frequency; based on the second magnetic field signal group, solving the second magnetic field signal component of each of the preset frequencies; obtaining the amplitude corresponding to each of the second magnetic field signal components, and combining the corresponding emission direction to obtain the spatial angle of the detector to be tested.

[0011] In one embodiment of the present application, the spatial state of the detector to be tested includes a spatial angle, and at least three non-collinear feature points are provided on the surface of the detector to be tested; wherein, a method for obtaining the spatial angle includes: obtaining the magnetic field signal of each feature point on the surface of the detector to be tested, and obtaining the spatial position of each feature point in combination with the spatial distribution of the magnetic field; performing vector calculation based on the spatial position of each feature point to obtain the spatial angle of the detector to be tested.

[0012] In one embodiment of the present application, based on the second magnetic field signal, the second magnetic field signal component of each preset frequency is extracted, and the component coefficient of each second magnetic field signal component in the second magnetic field signal is obtained, including: performing Fourier transform on the second magnetic field signal and converting it into a frequency domain form to obtain the second magnetic field signal component corresponding to each preset frequency.

[0013] In the second aspect, the present application provides a detector positioning system, which is applied to a X-ray imaging system, including: a magnetic field generating unit for generating a magnetic field; a signal receiving unit fixedly arranged on the surface of the detector to be tested, for receiving a magnetic field signal; a data processing unit, which is communicatively connected to the signal receiving unit, and obtains the magnetic field signal to execute the detector positioning method as described above.

[0014] In one embodiment of the present application, the magnetic field generating unit includes at least three conductive coils; each of the conductive coils generates a magnetic field signal corresponding to a preset frequency based on each preset emission direction.

[0015] In one embodiment of the present application, the signal receiving unit includes at least three signal receiving elements; each of the signal receiving elements is fixedly disposed at three non-collinear points on the surface of the detector to be tested.

[0016] As described above, the present application provides a detector positioning method and system, which obtains the magnetic field signal on the surface of the detector to be tested and combines it with the spatial distribution of the magnetic field to obtain the spatial state of the detector to be tested. The steps are simple and easy to operate, and positioning through magnetic field signals can avoid the influence of obstructions on the positioning accuracy of the detector to be tested, thereby improving the positioning accuracy of the detector to be tested, thereby achieving a better positioning effect of the detector to be tested. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a structural schematic diagram of a radiographic imaging system described in an embodiment of the present application.

[0018] Figure 2 Shown is a flow chart of a detector positioning method described in an embodiment of the present application.

[0019] Figure 3 Shown is a flow chart of a method for acquiring the spatial distribution of a magnetic field as described in an embodiment of the present application.

[0020] Figure 4 Shown is a flow chart of a method for acquiring the spatial position of a detector to be tested according to an embodiment of the present application.

[0021] Figure 5 Shown is a schematic diagram of the arrangement of a signal receiving element on the surface of a detector to be tested according to an embodiment of the present application.

[0022] Figure 6 Shown is a schematic diagram of the arrangement of a signal receiving element on the surface of another detector to be tested according to an embodiment of the present application.

[0023] Figure 7 Shown is a flow chart of a method for acquiring the spatial angle of a detector to be tested described in an embodiment of the present application.

[0024] Figure 8 Shown is a flow chart of another method for acquiring the spatial position of a detector to be tested described in an embodiment of the present application.

[0025] Figure 9 Shown is a schematic diagram of a scene for obtaining spatial angles of a detector to be tested as described in an embodiment of the present application.

[0026] Figure 10 Shown is a structural schematic diagram of a detector positioning system described in an embodiment of the present application.

[0027] Figure 11 Shown is a structural schematic diagram of a detector positioning device described in an embodiment of the present application.

[0028] Figure 12 Shown is a structural schematic diagram of a terminal described in an embodiment of the present application.

[0029] Description of Reference Numerals

[0030] 10: X-ray imaging system; 11: X-ray source; 12: Detector to be tested; 20: Detector positioning system; 21: Magnetic field generating unit; 22: Signal receiving unit; 30: Detector positioning device; 31: Signal acquisition module; 32: Magnetic field spatial distribution acquisition module; 33: Positioning module; 40: Terminal; 41: Processor; 42: Memory; 421: Operating system; 422: Application; 43: User interface; 44: Network interface; 45: Bus system. DETAILED DESCRIPTION

[0031] The following describes the embodiments of the present application through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0032] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0033] In the prior art, detector positioning is often achieved through visual positioning or radio frequency signal positioning. However, since both methods are affected by obstructions in front of the detector, errors in the detector position measurement occur, resulting in low detector positioning accuracy.

[0034] In response to the technical problems existing in the prior art, the following embodiments of the present application provide a detector positioning method and system, which obtains the magnetic field signal on the surface of the detector to be tested and combines it with the spatial distribution of the magnetic field to obtain the spatial state of the detector to be tested, thereby realizing the positioning of the detector to be tested. Since the magnetic field will not be absorbed or reflected by non-magnetic materials, the positioning of the detector to be tested based on the magnetic field signal is not affected by obstructions, thereby effectively improving the positioning accuracy of the detector to be tested, which is beneficial to the practical application of the X-ray imaging system.

[0035] The following embodiments of this application provide a detector positioning method and system, including but not limited to applications in detector positioning scenarios in X-ray imaging systems. The following description uses the positioning of a flat-panel detector as an example. It should be noted that the detector positioning method and system provided in the following embodiments of this application can also be used to position other types of detectors, and this application does not specifically limit this.

[0036] like Figure 1 As shown, in order to facilitate those skilled in the art to understand the detector positioning method described in this embodiment, this embodiment exemplarily provides a radiographic imaging system 10, including: a ray source 11 and a detector to be tested 12. The ray source 11 is used to provide the ray beam required for imaging, and the detector to be tested 12 is used to receive the ray beam to generate a detection image. Since the distance between the detector to be tested 12 and the ray source 11 and the distance between the object to be tested and the detector to be tested 12 directly affect the geometric magnification, resolution and degree of distortion of the image, a slight offset in the position of the detector to be tested 12 may cause image blur or projection distortion. Ideally, the detector to be tested 12 should be located on the center line of the ray beam emitted by the ray source 11 to ensure uniform irradiation and minimal geometric distortion. Based on this, this embodiment provides a detector positioning method for achieving precise positioning of the detector to be tested 12.

[0037] The technical solutions in the embodiments of the present application will be described in detail below with reference to the accompanying drawings in the embodiments of the present application.

[0038] like Figure 2 As shown, this embodiment provides a detector positioning method, including:

[0039] S100, obtaining first magnetic field signals and spatial positions of a plurality of test points.

[0040] The first magnetic field signal is a signal of the magnetic field generated by the magnetic field generating unit at the spatial position corresponding to each of the test points. The magnetic field generating unit is used to generate a magnetic field.

[0041] Specifically, a magnetic field signal receiver is provided at a spatial position corresponding to each of the test points to receive a magnetic field signal, thereby obtaining a first magnetic field signal corresponding to each of the test points. Exemplarily, the magnetic field signal receiver is a sensor, including but not limited to any one of a Hall sensor, a magnetoresistive sensor, a tunnel magnetoresistive sensor, an inductive magnetic sensor, or a fluxgate sensor, so as to transmit the received magnetic field signal to a data processing unit via the sensor to facilitate execution of subsequent steps.

[0042] It should be noted that based on the first magnetic field signal and spatial position corresponding to each test point, the spatial distribution of the magnetic field signal generated by the magnetic field generating unit when at the corresponding position can be obtained. Based on this, when it is necessary to locate the detector under test, the magnetic field distribution on the surface of the detector under test is obtained and combined with the spatial distribution of the magnetic field signal generated by the magnetic field generating unit for analysis to determine the spatial state of the detector under test, thereby achieving the positioning of the detector under test.

[0043] Furthermore, in order to improve the positioning accuracy of the detector to be tested, each of the test points is distributed at different directions and distances from the magnetic field generating unit to improve the accuracy of the spatial distribution of the acquired magnetic field signal, thereby improving the accuracy of the acquired spatial state of the detector to be tested.

[0044] S200 , obtaining a magnetic field spatial distribution based on the first magnetic field signal of each of the test points and in combination with the spatial position of each of the test points.

[0045] The magnetic field spatial distribution is used to characterize the spatial distribution of the magnetic field signal generated when the magnetic field generating unit is at a corresponding position.

[0046] Specifically, based on the spatial position of each test point and the first magnetic field signal, a mapping relationship between the first magnetic field signal and the spatial position is obtained by a mathematical method to serve as the magnetic field spatial distribution. Exemplarily, the mathematical method is an interpolation method, which obtains the change of the magnetic field signal between adjacent test points by linear interpolation or polynomial interpolation, thereby obtaining the magnetic field spatial distribution; or, the mathematical method is a numerical simulation method, which divides the spatial region into a finite number of units, uses the discrete form of the partial differential equation, solves the magnetic field signal on each unit, and combines the boundary conditions and initial conditions to obtain the magnetic field signal distribution; or, the mathematical method is a data fitting method, which performs data fitting based on the spatial position of each test point and the first magnetic field signal, obtains the change of the first magnetic field signal relative to the spatial position, and obtains the magnetic field spatial distribution.

[0047] In some optional embodiments, such as Figure 3 As shown, the mathematical method is a data fitting method, and the method for obtaining the spatial distribution of the magnetic field includes:

[0048] S210 , obtaining a distance between a plane corresponding to each of the test point sets and the magnetic field generating unit as a plane height.

[0049] The test point set is a collection of the test points located in the same plane. The test points are located on a plurality of mutually parallel planes. The directions of the planes can be set according to actual needs.

[0050] Exemplarily, the xyz three-dimensional coordinate system is constructed with the position of the magnetic field generating unit as the origin. Each plane is a plane parallel to the xy plane and passing through at least one of the test points. The spatial position of each test point is represented by the corresponding coordinate within the xyz three-dimensional coordinate system. Based on this, the plane height corresponding to each plane is represented by the z-axis coordinate value of any test point within the plane.

[0051] S220 , performing surface fitting based on the first magnetic field signal and the spatial position corresponding to each test point in each test point set, to obtain a magnetic field plane distribution of a plane corresponding to each test point set.

[0052] Specifically, the planar position of each test point in the corresponding plane is obtained, and the distribution of the first magnetic field signal in each plane is obtained by data fitting.

[0053] Exemplarily, for each of the planes, an xy plane coordinate system corresponding to the xyz three-dimensional coordinate system is constructed, that is, the projection point of the magnetic field generating unit in each of the planes is used as the origin, the positive direction of the x-axis of the xyz three-dimensional coordinate system is used as the positive direction of the x-axis of each of the xy plane coordinate systems, and the positive direction of the y-axis of the xyz three-dimensional coordinate system is used as the positive direction of the y-axis of each of the xy plane coordinate systems, to construct the corresponding xy plane coordinate system.

[0054] Based on this, the x-axis coordinate value of each test point in the xyz three-dimensional coordinate system is the corresponding plane x-axis coordinate, and the y-axis coordinate value of each test point in the xyz three-dimensional coordinate system is the corresponding plane y-axis coordinate, and the plane coordinates of each test point in the corresponding xy plane coordinate system are obtained to represent its planar position in the plane.

[0055] Furthermore, for a single plane, the first magnetic field signal and plane coordinates corresponding to each test point in the plane are obtained to perform surface fitting, and the change of the magnetic field signal relative to the plane coordinates in the plane is obtained, that is, the plane distribution of the magnetic field in the plane is obtained.

[0056] S230, performing depth convolution fitting based on each of the magnetic field plane distributions and the corresponding plane heights to obtain the magnetic field spatial distribution.

[0057] Specifically, a preset convolutional structure deep learning model is used to perform data fitting on each of the magnetic field plane distributions and the corresponding plane heights, thereby obtaining the distribution of the first magnetic field signal in space, that is, obtaining the magnetic field spatial distribution. Deep convolution fitting based on the convolutional structure deep learning model can achieve high-precision fitting of complex relationships while maintaining relatively high computational efficiency, thereby improving the accuracy of the magnetic field spatial distribution and, in turn, the positioning accuracy of the detector under test.

[0058] It should be noted that those skilled in the art should be aware of the construction and training methods of the convolutional structure deep learning model, which will not be specifically explained in this embodiment.

[0059] In this embodiment, by dividing each of the test points into the test point sets corresponding to each of the planes, surface fitting is first performed based on each of the planes to obtain the plane distribution of each of the magnetic fields, and then deep convolution fitting is performed based on each of the magnetic field plane distributions and the corresponding plane heights, thereby reducing the amount of calculation in each step of the data fitting process, thereby increasing the calculation speed of data fitting and effectively improving the efficiency of obtaining the spatial distribution of the magnetic field.

[0060] S300 , obtaining a second magnetic field signal group on the surface of the detector to be tested, and obtaining a spatial state of the detector to be tested based on the second magnetic field signal group and in combination with the magnetic field spatial distribution, so as to locate the detector to be tested.

[0061] The second magnetic field signal group is used to characterize the magnetic field distribution on the surface of the detector to be tested. Specifically, at least one signal receiving element is provided on the surface of the detector to be tested, and the signal receiving element is used to receive the magnetic field distribution on the surface of the detector based on the magnetic field signal received by each signal receiving element. Exemplarily, similar to the magnetic field signal receiving element, the signal receiving element is a sensor, including but not limited to any one of a Hall sensor, a magnetoresistive sensor, a tunnel magnetoresistive sensor, an inductive magnetic sensor or a fluxgate sensor, so as to transmit the received second magnetic field signal to the data processing unit through the sensor, so as to perform subsequent steps.

[0062] In some optional embodiments, the spatial state of the detector under test includes a spatial position and a spatial angle. The spatial position is used to represent the position information of the detector under test, such as the distance from the radiation source 11; and the spatial angle is used to represent the posture information of the detector under test, such as the pitch angle of the detector under test.

[0063] It should be noted that each of the signal receiving elements is fixedly arranged on each characteristic point on the surface of the detector to be tested. The process of obtaining the spatial position of the detector to be tested is actually to obtain the spatial position of each of the characteristic points, and based on the spatial position of each of the characteristic points, characterize the spatial position of the detector to be tested.

[0064] Specifically, if Figure 4 As shown, the method for obtaining the spatial position of the detector to be tested includes:

[0065] S311 , obtaining magnetic field signals of each characteristic point on the surface of the detector to be tested, and obtaining the spatial position of each characteristic point in combination with the spatial distribution of the magnetic field.

[0066] Specifically, the magnetic field signal corresponding to each of the feature points is extracted from the second magnetic field signal group; and for a single feature point, its spatial position is acquired based on the corresponding magnetic field signal and the magnetic field spatial distribution.

[0067] S312: Determine the spatial position of the detector to be tested based on the spatial position of each of the feature points.

[0068] In order to facilitate those skilled in the art to understand the spatial position acquisition method described in this embodiment, specific examples are given below.

[0069] like Figure 5As shown, the surface of the detector under test is provided with four signal receiving elements, located at the four corners of the flat-panel detector. Based on the corresponding magnetic field signal obtained by each signal receiving element, and combined with the spatial distribution of the magnetic field, the spatial position of each signal receiving element is determined, that is, the spatial position of the four corners of the detector under test. Based on this, the spatial position of the detector under test can be characterized by the spatial position of the four corners.

[0070] Or, as Figure 6 As shown, the surface of the detector under test is provided with a signal receiving element at the center. Based on the magnetic field signal it acquires and the spatial distribution of the magnetic field, the spatial position of the signal receiving element, i.e., the spatial position of the center of the detector under test, is determined. Therefore, the spatial position of the detector under test can be characterized by the spatial position of the center.

[0071] It should be noted that, for a detector with a larger area, a plurality of characteristic points are generally set to improve the accuracy of positioning the detector to be tested.

[0072] In some optional embodiments, such as Figure 7 As shown, the method for obtaining the spatial angle of the detector to be measured includes:

[0073] S321: Obtain the spatial position of each feature point.

[0074] Specifically, the method for obtaining the spatial position of each feature point can be found in the above content, which will not be described in detail in this embodiment.

[0075] S322: Perform vector calculation based on the spatial position of each of the feature points to obtain the spatial angle of the detector to be tested.

[0076] Specifically, based on the spatial position of each of the feature points, at least two plane vectors are calculated, and based on the plane vectors, the normal vector of the plane where the detector to be measured is located is calculated to determine the spatial angle of the detector to be measured.

[0077] For example, using the x-axis in the xyz three-dimensional coordinate system as the reference for the spatial angle of the detector under test, and obtaining the angle between the normal vector and the x-axis, the actual angle between the detector under test and the x-axis and the angle between the normal vector and the x-axis are complementary. Similarly, by obtaining the angles between the detector under test and the y-axis and the z-axis, the spatial angle of the detector under test can be characterized.

[0078] It should be noted that, in order to obtain at least two plane vectors based on each of the feature points, the surface of the detector to be tested is provided with at least three non-collinear feature points.

[0079] In other optional implementations, such as Figure 8 As shown, the method for obtaining the spatial angle of the detector to be measured includes:

[0080] S321', obtaining the emission direction corresponding to each of the preset frequency magnetic field signals.

[0081] The magnetic field generating unit emits at least three magnetic field signals with different emission directions, different preset frequencies and the same magnetic field strength, and each of the preset frequencies is a frequency corresponding to each of the magnetic field signals.

[0082] Specifically, the emission direction of each preset frequency magnetic field signal is a pre-set direction. By obtaining the historical setting data of the magnetic field generating unit, the emission direction corresponding to each preset frequency magnetic field signal can be obtained; or, the emission direction corresponding to the preset frequency magnetic field signal can be obtained by manual measurement.

[0083] Exemplarily, the magnetic field generating unit emits three magnetic field signals, and constructs the xyz three-dimensional coordinate system with the spatial position of the magnetic field generating unit as the origin, wherein the emission directions corresponding to the three magnetic field signals are the positive direction of the x-axis, the positive direction of the y-axis, and the positive direction of the z-axis, respectively.

[0084] S322': Calculate the second magnetic field signal components of each of the preset frequencies based on the second magnetic field signal group.

[0085] Wherein, each of the second magnetic field signal components is a magnetic field signal in each emission direction and is received by the surface of the detector to be tested.

[0086] It should be noted that since the propagation of magnetic field signals is directional, the detector to be tested can receive different intensities of magnetic field signals at different angles. Based on this, the spatial angle of the detector to be tested can be analyzed by solving the second magnetic field signal components on the surface of the detector to be tested.

[0087] Exemplarily, each second magnetic field signal component is solved by Fourier transform. Specifically, the second magnetic field signal group is Fourier transformed and converted into a frequency domain form. Among them, Fourier transform is a linear transformation, which can decompose a complex time domain signal into a combination of sine waves and cosine waves of different frequencies. Since the second magnetic field signal group is actually composed of magnetic field signals of each preset frequency, after Fourier transform is performed on it, it can be decomposed into frequency signals corresponding to each preset frequency, thereby realizing the decomposition of the second magnetic field signal group and obtaining the second magnetic field signal components corresponding to each preset frequency.

[0088] S323', obtaining the amplitude corresponding to each second magnetic field signal component, and combining the corresponding emission direction to obtain the spatial angle of the detector to be tested.

[0089] The amplitude is used to characterize the strength of each second magnetic field signal component. Based on the amplitude, the angle between the direction of the magnetic field signal corresponding to the preset frequency and the direction in which the magnetic field signal is received by the detector under test can be obtained. Based on these angles, combined with the emission direction corresponding to each magnetic field signal at the preset frequency, the spatial angle of the detector under test can be obtained. It should be noted that those skilled in the art should be aware of the method for obtaining the corresponding amplitude of each second magnetic field signal component, and this embodiment will not be specifically explained here.

[0090] Specifically, the following exemplifies a specific example of obtaining the spatial angle of the detector to be measured based on the amplitude of the second magnetic field signal component. Figure 9 As shown in the figure, arrow A indicates the direction in which the detector to be tested receives the magnetic field signal, arrow B indicates the emission direction of the second magnetic field signal component B, and arrow C indicates the emission direction of the second magnetic field signal component C. Based on the emission directions of the two second magnetic field signal components, the size of the direction angle α is obtained, and then the size of its complementary angle β is obtained. The amplitudes of the two second magnetic field signal components are obtained, that is, Figure 9 The lengths of the two sides of triangle X are b and c respectively. Combining the cosine theorem of the triangle, we can get the length of the side corresponding to arrow A:

[0091]

[0092] Furthermore, based on the cosine theorem of a triangle, the angle θ1 between the direction in which the detector to be tested receives the magnetic field signal and the emission direction of the second magnetic field signal component B and the angle θ2 between the direction in which the detector to be tested receives the magnetic field signal and the emission direction of the second magnetic field signal component C are obtained:

[0093] θ1=sin -1 (a 2 +b 2 -c 2 ) / 2ab

[0094] θ2=α-θ1

[0095] Furthermore, since the direction in which the detector to be tested receives the magnetic field signal is usually perpendicular to its plane, that is, the angle between the detector to be tested and the emission direction of the second magnetic field signal component B is the complementary angle of θ1, and the angle between the detector to be tested and the emission direction of the second magnetic field signal component C is the complementary angle of θ2, based on this, the spatial angle of the detector to be tested can be determined.

[0096] In order to facilitate those skilled in the art to understand the spatial position acquisition method described in this embodiment, specific examples are given below.

[0097] For example, the magnetic field generating unit emits three magnetic field signals, wherein the emission directions corresponding to the three magnetic field signals are the positive direction of the x-axis, the positive direction of the y-axis, and the positive direction of the z-axis, respectively. Each of the second magnetic field signal components and its corresponding amplitude is obtained by Fourier transform, wherein each of the amplitudes is equal. Based on this, it is easy to obtain that the angle between the direction in which the magnetic field signal is received by the detector to be tested and the positive direction of the x-axis is 45°, the angle between the direction in which the magnetic field signal is received by the detector to be tested and the positive direction of the y-axis is 45°, and the angle between the direction in which the magnetic field signal is received by the detector to be tested and the positive direction of the z-axis is 45°, that is, the angle between the detector to be tested and each coordinate axis in the xyz three-dimensional coordinate system is 45°, which serves as the spatial angle of the detector to be tested.

[0098] It should be noted that, in order to obtain the spatial angle of the detector to be measured, the magnetic field generating unit sends out magnetic field signals in at least three different emission directions.

[0099] The spatial angle of the detector to be tested is obtained based on amplitude calculation, which has high precision and is conducive to achieving more accurate positioning of the detector to be tested.

[0100] In order to implement the above detector positioning method, this embodiment also includes a detector positioning system, which is applied to a radiographic imaging system to implement the above detector positioning method. Figure 10 As shown, the detector positioning system 20 includes a magnetic field generating unit 21, a signal receiving unit 22 and a data processing unit (not shown in the figure). The magnetic field generating unit 21 is used to generate a magnetic field. Exemplarily, the magnetic field generating unit 21 generates a magnetic field signal based on Ampere's law through a conductive coil, and controls the intensity of the generated magnetic field signal based on the magnitude of the current, changes the frequency of the generated magnetic field signal by changing the frequency of the current, and changes the emission direction of the generated magnetic field signal by changing the direction of the conductive coil.

[0101] Furthermore, for the method of obtaining the spatial angle of the detector to be tested through steps S321' to S323', the magnetic field generating unit 21 includes at least three conductive coils, each conductive coil generates a magnetic field signal with a different preset frequency and the same magnetic field strength based on a different emission direction.

[0102] The signal receiving unit 22 is fixedly mounted on the surface of the detector to be tested and is configured to receive magnetic field signals. Specifically, the signal receiving unit 22 includes at least one signal receiving element fixed to the surface of the detector to be tested. Exemplarily, the signal receiving element is a sensor, including but not limited to any one of a Hall effect sensor, a magnetoresistive sensor, a tunnel magnetoresistive sensor, an inductive magnetic sensor, or a fluxgate sensor. The sensor transmits the received magnetic field signal to the data processing unit to facilitate execution of the above-described detector positioning method.

[0103] Furthermore, for the method of obtaining the spatial angle of the detector to be tested through steps S321 to S322, the signal receiving unit includes at least three signal receiving elements, and each of the signal receiving elements is fixedly arranged at three non-collinear points on the surface of the detector to be tested.

[0104] The data processing unit is in communication with the signal receiving unit 22 to obtain the magnetic field signal and execute the above-mentioned detector positioning method.

[0105] It should be noted that the process of obtaining the spatial distribution of the magnetic field in steps S100 to S200 is also implemented based on the above-mentioned detector positioning system 20, wherein the magnetic field generating unit 21 generates a magnetic field signal; the signal receiving unit 22 is used to receive the magnetic field signal, and can be fixed to the spatial position corresponding to each of the test points to receive the signal, or it can be fixed on the test detector to receive the signal; the data processing unit is communicated with the signal receiving unit 22 to obtain the magnetic field signal and process and analyze it to obtain the spatial distribution of the magnetic field.

[0106] like Figure 11 As shown, a detector positioning device 30 provided in this embodiment includes a signal acquisition module 31 , a magnetic field spatial distribution acquisition module 32 and a positioning module 33 .

[0107] The signal acquisition module 31 is used to acquire first magnetic field signals and spatial positions of a plurality of test points; the first magnetic field signal is a signal of the magnetic field generated by the magnetic field generating unit at the spatial position corresponding to each of the test points.

[0108] The magnetic field spatial distribution acquisition module 32 is configured to acquire the magnetic field spatial distribution based on the first magnetic field signal of each test point in combination with the spatial position of each test point.

[0109] The positioning module 33 is used to obtain a second magnetic field signal group from the surface of the detector to be tested, and based on the second magnetic field signal group and the magnetic field spatial distribution, obtain the spatial state of the detector to be tested to locate the detector to be tested.

[0110] Based on the same technical concept, the detector positioning method provided by the embodiment of the present invention can be implemented on the terminal side or the server side.

[0111] like Figure 12FIG2 shows an optional hardware structure diagram of a terminal provided in an embodiment of the present invention. Terminal 40 can be a mobile phone, a computer, a tablet device, a personal digital assistant, a factory backend processing device, or the like. Terminal 40 includes at least one processor 41, a memory 42, at least one network interface 44, and a user interface 43. The various components in the device are coupled together via a bus system 45. It will be appreciated that bus system 45 is used to enable communication between these components. In addition to a data bus, bus system 45 also includes a power bus, a control bus, and a status signal bus.

[0112] The user interface 43 may include a display, a keyboard, a mouse, a trackball, a click gun, keys, buttons, a touch pad or a touch screen.

[0113] It will be appreciated that the memory 42 may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. The non-volatile memory may be a read-only memory (ROM) or a programmable read-only memory (PROM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM) and synchronous static random access memory (SSRAM). The memories represented by the embodiments of the present invention are intended to include, but are not limited to, these and any other suitable types of memories.

[0114] The memory 42 in the embodiment of the present invention is used to store various types of data to support the operation of the terminal. Examples of such data include: any executable program used to operate on the terminal 40, such as an operating system 421 and an application 422; the operating system 421 includes various system programs, such as a framework layer, a core library layer, a driver layer, etc., for implementing various basic services and processing hardware-based tasks. The application 422 can include various applications, such as a media player (MediaPlayer), a browser (Browser), etc., for implementing various application services. The detector positioning method provided in the embodiment of the present invention can be included in the application 422.

[0115] The method disclosed in the above embodiment of the present invention can be applied to the processor 41 or implemented by the processor 41. The processor 41 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by the hardware integrated logic circuit in the processor 41 or by instructions in the form of software. The above processor may be a general-purpose processor, a digital signal processor (DSP), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The processor 41 can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiment of the present invention. The processor 41 may be a microprocessor or any conventional processor, etc. The steps of the accessory optimization method provided in the embodiment of the present invention can be directly embodied as being executed by a hardware decoding processor, or can be executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium, which is located in a memory. The processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0116] In an exemplary embodiment, the terminal 40 may be configured to execute the aforementioned method using one or more application specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), or complex programmable logic devices (CPLDs).

[0117] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the program is called by a processor, the detector positioning method provided by the present invention is implemented.

[0118] Among them, a computer-readable storage medium can be a tangible device that can hold and store instructions used by an instruction execution device. The computer-readable storage medium can be, for example, (but not limited to) an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, and a mechanical encoding device.

[0119] The computer-readable program characterized herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium in each computing / processing device.

[0120] To sum up, the present application uses magnetic field signals to locate the detector to be tested. The steps are simple and easy to operate, and the magnetic field signals are not affected by obstructions, thereby avoiding the reduction of the positioning accuracy of the detector to be tested due to obstructions, effectively improving the positioning accuracy of the detector to be tested, and having high industrial application value.

[0121] The descriptions of the processes or structures corresponding to the above figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0122] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. A detector positioning method, comprising: Acquire first magnetic field signals and spatial positions of a plurality of test points; the first magnetic field signals are signals of the magnetic field generated by the magnetic field generating unit at the spatial positions corresponding to the test points; Acquire a magnetic field spatial distribution based on the first magnetic field signal of each test point and in combination with the spatial position of each test point; A second magnetic field signal group is obtained from the surface of the detector to be tested, and based on the second magnetic field signal group and in combination with the magnetic field spatial distribution, a spatial state of the detector to be tested is obtained to locate the detector to be tested.

2. The method according to claim 1, characterized in that The obtaining of the magnetic field spatial distribution based on the first magnetic field signal of each test point in combination with the spatial position of each test point includes: Based on the spatial position of each of the test points and the first magnetic field signal, a mapping relationship between the first magnetic field signal and the spatial position is obtained by a mathematical method to serve as the magnetic field spatial distribution; The mathematical method is any one of an interpolation method, a numerical simulation method or a data fitting method.

3. The method according to claim 2, characterized in that The test points are located on a plurality of mutually parallel planes, and the spatial distribution of the magnetic field is obtained by a mathematical method based on the spatial position of each test point and the first magnetic field signal, including: Obtaining the distance between the plane corresponding to each of the test point sets and the magnetic field generating unit as the plane height; Performing surface fitting based on the first magnetic field signal and the spatial position corresponding to each test point in each test point set to obtain a magnetic field plane distribution of a plane corresponding to each test point set; A depth convolution fitting is performed based on each of the magnetic field plane distributions and the corresponding plane heights to obtain the magnetic field spatial distribution.

4. The method according to claim 1, wherein The spatial state of the detector to be tested includes a spatial position; the second magnetic field signal group includes a magnetic field signal of at least one characteristic point on the surface of the detector to be tested; The method for obtaining the spatial position includes: Acquire the magnetic field signal of each characteristic point on the surface of the detector to be tested, and obtain the spatial position of each characteristic point based on the spatial distribution of the magnetic field; The spatial position of the detector to be tested is determined based on the spatial position of each of the feature points.

5. The method according to claim 1, characterized in that The magnetic field generating unit emits at least three magnetic field signals of different preset frequencies, wherein the magnetic field signals of the preset frequencies have different emission directions and the same magnetic field strength; the spatial state of the detector to be measured includes a spatial angle; The method for obtaining the spatial angle includes: Obtaining the emission direction corresponding to each of the preset frequency magnetic field signals; Calculating the second magnetic field signal components of each of the preset frequencies based on the second magnetic field signal group; The amplitude corresponding to each second magnetic field signal component is obtained, and the spatial angle of the detector to be tested is obtained in combination with the corresponding emission direction.

6. The method according to claim 1, characterized in that The spatial state of the detector to be tested includes a spatial angle, and the surface of the detector to be tested is provided with at least three non-collinear feature points; The method for obtaining the spatial angle includes: Acquire the magnetic field signal of each characteristic point on the surface of the detector to be tested, and obtain the spatial position of each characteristic point based on the spatial distribution of the magnetic field; Vector calculation is performed based on the spatial position of each of the feature points to obtain the spatial angle of the detector to be measured.

7. The method according to claim 5, characterized in that The extracting, based on the second magnetic field signal, the second magnetic field signal components of each of the preset frequencies, and obtaining component coefficients of each of the second magnetic field signal components in the second magnetic field signal, includes: Performing Fourier transform on the second magnetic field signal to convert it into a frequency domain form to obtain the second magnetic field signal components corresponding to each of the preset frequencies.

8. A detector positioning system, applied to a radiographic imaging system, characterized in that: include: A magnetic field generating unit, used for generating a magnetic field; A signal receiving unit, fixedly mounted on the surface of the detector to be tested, for receiving magnetic field signals; A data processing unit is communicatively connected to the signal receiving unit, and acquires the magnetic field signal to execute the detector positioning method according to any one of claims 1 to 7.

9. The system according to claim 8, characterized in that The magnetic field generating unit includes at least three conductive coils; each of the conductive coils generates a magnetic field signal corresponding to a preset frequency based on each preset emission direction.

10. The system according to claim 8, wherein: The signal receiving unit includes at least three signal receiving components; each of the signal receiving components is fixedly arranged at three non-collinear points on the surface of the detector to be tested.

Images