Method and system for measuring magnetic probe position

Abstract

The invention relates to the field of nuclear fusion technology, and discloses a method and a system for measuring the position of a magnetic probe. The method comprises: using a laser tracker to establish an absolute coordinate system of a vacuum chamber based on known preset position coordinates; using the same set of targets fixed in the vacuum chamber to convert the coordinate system of a multi-joint mechanical arm fixed in the vacuum chamber into an absolute coordinate system; using the multi-joint mechanical arm to measure the position of the magnetic probe in the absolute coordinate system. In the embodiment of measuring the position of the magnetic probe by using the multi-joint mechanical arm, the multi-joint mechanical arm arranged in the vacuum chamber can more accurately detect the position of the magnetic probe located at the bottom of the vacuum chamber, thereby solving the technical problem of inaccurate detection of the position of the magnetic probe located at the bottom of the vacuum chamber in the method of using a laser tracker alone to detect positioning holes on the surface of the magnetic probe to determine the position of the magnetic probe.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear fusion, and in particular to a method and system for measuring the position of a magnetic probe. Background Art

[0002] Magnetic measurement is one of the most basic diagnostic systems of the tokamak device, and the magnetic probe is an important component of magnetic measurement. Magnetic probe is an important measurement method for the identification and feedback control of the plasma magnetic field configuration in the tokamak, the study of magnetic fluid instability and active control.

[0003] The magnetic probe is a small solenoid coil installed at the fire boundary of the plasma. Its working principle is based on the law of electromagnetic induction. When the magnetic field in the space where the coil is located changes, an induced electromotive force will be generated at both ends of the coil due to the change in the magnetic flux passing through the cross-sectional area of ​​the coil.

[0004] As an important diagnostic tool for the Tokamak device, the accuracy of the magnetic probe is particularly important. Its measurement accuracy will affect the accuracy of the plasma magnetic field configuration reconstruction and feedback control, and affect the stable operation capability of the device. From the experimental results of various devices, when the error of the magnetic probe is greater than 1%, it will have a significant impact on the accuracy of plasma equilibrium inversion. Therefore, the position of the magnetic probe needs to be accurately measured to facilitate the subsequent inversion of the plasma configuration based on the magnetic probe position data and the magnetic flux data measured by the magnetic probe, and further realize the feedback control of the plasma.

[0005] However, in the related art, a laser tracker is usually used alone to detect the positioning holes on the surface of the magnetic probe to determine the position of the magnetic probe; the detection accuracy of this detection method is limited by the performance of the laser tracker, and the measurement is inaccurate. Summary of the invention

[0006] In view of this, the present invention provides a method and system for measuring the position of a magnetic probe in a nuclear fusion device to solve the problem that the detection accuracy of the detection method using a laser tracker in the related art is limited by the performance of the laser tracker and the measurement is inaccurate.

[0007] In a first aspect, the present invention provides a method for measuring the position of a magnetic probe, wherein the magnetic probe is installed in a vacuum chamber of a fusion device, and the measurement method comprises: using a laser tracker to establish an absolute coordinate system for the vacuum chamber based on known preset position coordinates; using the same set of targets fixed in the vacuum chamber to convert the coordinate system of a multi-joint robotic arm fixed in the vacuum chamber into an absolute coordinate system; and using the multi-joint robotic arm to measure the position of the magnetic probe in the absolute coordinate system.

[0008] As an exemplary embodiment, the method of converting the coordinate system of a multi-joint robotic arm fixed in the vacuum chamber into an absolute coordinate system using the same set of targets fixed in the vacuum chamber includes: measuring first target coordinate values ​​of multiple targets fixed in the vacuum chamber in the absolute coordinate system using the laser tracker; measuring second target coordinate values ​​of multiple targets using the multi-joint robotic arm fixed inside the vacuum chamber; and converting the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the first target coordinate values ​​and the second target coordinate values.

[0009] As an exemplary embodiment, the conversion of the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the first target coordinate value and the second target coordinate value includes: establishing the coordinate system of the multi-joint robotic arm using the fixed point of the multi-joint robotic arm as the coordinate origin; and converting the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the correspondence between the first target coordinate value and the second target coordinate value.

[0010] As an exemplary embodiment, the measuring of the position of the magnetic probe using the multi-joint robotic arm in the absolute coordinate system includes: using the multi-joint robotic arm to perform multi-point measurement of the magnetic probe to obtain absolute coordinate values ​​of the multi-point positions of the magnetic probe in the absolute coordinate system; and calculating the position information of the magnetic probe based on the absolute coordinate values ​​of the multi-point positions.

[0011] As an exemplary embodiment, the multi-point measurement of the magnetic probe is performed using the multi-joint robotic arm to obtain the absolute coordinate values ​​of the multi-point positions of the magnetic probe in an absolute coordinate system, including: using the multi-joint robotic arm to measure the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; the calculation of the position information of the magnetic probe based on the absolute coordinate values ​​of the multi-point positions includes: calculating the geometric center coordinate value of the magnetic probe according to the first absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe outer shell.

[0012] As an exemplary embodiment, the method of calculating the geometric center coordinate value of the spatial position of the magnetic probe according to the first absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe shell includes: taking the average of the first absolute coordinate value and projecting it to the shell surface of the magnetic probe to obtain the projection point position coordinate value of the shell surface; taking the average and projecting the second absolute coordinate value to obtain the surface center coordinates of each shell surface; calculating the normal vector of the shell surface of the magnetic probe using the second absolute coordinate value or using the projection point position coordinate value and the second absolute coordinate value; and calculating the projection point position coordinate value according to the shell surface.

[0013] As an exemplary embodiment, the position information also includes the inclination of the magnetic probe in space. The position information of the magnetic probe is calculated based on the absolute coordinate values ​​of multiple points, and also includes: calculating the angle between the normal vector of each shell surface and the normal vector of the horizontal plane; wherein the horizontal plane normal vector is determined by the absolute coordinate system; projecting the normal vector of the shell surface to the plane of the magnetic probe array, and obtaining the reference direction of the angle based on a preset reference direction; and determining the inclination based on the angle and the reference direction.

[0014] In a second aspect, the present invention provides a system for measuring the position of a magnetic probe, wherein the magnetic probe is installed in a vacuum chamber of a fusion device, and the measurement system includes a laser tracker and a multi-joint robotic arm, wherein the laser tracker is arranged on the outside of the vacuum chamber, and the laser tracker establishes an absolute coordinate system of the vacuum chamber based on preset position coordinates; the multi-joint robotic arm is fixed on the inside of the vacuum chamber, and the laser tracker and the multi-joint robotic arm measure the coordinate values ​​of the same group of multiple target points to convert the coordinate system of the multi-joint robotic arm into an absolute coordinate system; the multi-joint robotic arm measures the position of the magnetic probe in the absolute coordinate system to obtain the position information of the magnetic probe.

[0015] As an exemplary embodiment, it also includes a data processing device, which is connected to the laser tracker and the multi-joint robotic arm respectively, and is used to collect measurements of the laser tracker and the multi-joint robotic arm; the laser tracker measures the first target point coordinate values ​​of multiple targets fixed inside the vacuum chamber in the absolute coordinate system; the multi-joint robotic arm measures the second target point coordinate values ​​of multiple targets; the data processing device converts the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the first target point coordinate values ​​and the second target point coordinate values.

[0016] As an exemplary embodiment, the multi-joint robotic arm measures the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; the data processing device calculates the geometric center coordinate value of the magnetic probe and the angle parameters between the surface of the magnetic probe and the horizontal plane based on the first absolute coordinate value and the second absolute coordinate value.

[0017] The above-mentioned method for measuring the position of the magnetic probe of the present invention utilizes a laser tracker to establish an absolute coordinate system of the vacuum chamber based on known preset position coordinates; utilizes the same set of targets fixed in the vacuum chamber to convert the coordinate system of a multi-joint robotic arm fixed in the vacuum chamber into an absolute coordinate system; utilizes the multi-joint robotic arm to measure the position of the magnetic probe in the absolute coordinate system; in the implementation method of using the multi-joint robotic arm to measure the position of the magnetic probe, the multi-joint robotic arm arranged in the vacuum chamber can more accurately detect the position of the magnetic probe located at the bottom of the vacuum chamber, thereby solving the technical problem of inaccurate detection of the position of the magnetic probe located at the bottom of the vacuum chamber in the method of using a laser tracker alone to detect the positioning holes on the surface of the magnetic probe to determine the position of the magnetic probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 is a schematic diagram of the structure of a magnetic probe array;

[0020] Figure 2 is a partial enlarged view of the magnetic probe array;

[0021] Figure 3 is a flow chart of a method for measuring a magnetic probe position according to an embodiment of the present invention;

[0022] Figure 4 is a schematic diagram of the position of a magnetic probe in the vacuum chamber space;

[0023] Figure 5 is a schematic diagram of a preset reference direction according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0025] The magnetic probe is a small solenoid coil installed at the boundary of the plasma. Its working principle is based on the law of electromagnetic induction. When the magnetic field in the space where the coil is located changes, an induced electromotive force will be generated at both ends of the coil due to the change of the magnetic flux passing through the cross-sectional area of ​​the coil. Figure 1 This is a schematic diagram of the structure of a magnetic probe array. Figure 2 is a partial enlarged view of the magnetic probe array, such as Figure 1 , Figure 2 As shown, the skeleton 11, the winding 13 and the shell 12 form a magnetic probe array, which detects the magnetic field in the space where the coil is located. The surface of the shell 12 of each magnetic probe is provided with a positioning hole 121.

[0026] Based on this, in the related art, a laser tracker is usually used to detect the positioning holes 121 set on the surface of the housing 12 of each magnetic probe to determine the position of the magnetic probe. In this implementation, the coordinates of the reflector pre-set in the vacuum chamber are first measured by a laser tracker to establish an absolute coordinate system, and then the positioning holes on the surface of the magnetic probe are detected based on the absolute coordinate system to determine the position of the magnetic probe.

[0027] However, in actual applications, it was found that when a laser tracker was used to measure the magnetic probe located at the bottom of the vacuum chamber in a fusion device, the measurement error was large; specifically, after the inventor used a laser tracker to measure the position of the magnetic probe multiple times, the error percentage between the simulated value and the measured value was used to represent the measurement error of the laser tracker. For example, 56 magnetic probes can be set and numbered respectively, and the measurement results of some of the magnetic probes are selected; specifically, first, 5 PF coils numbered PF1 to PF5 are pre-set in the vacuum chamber, and the set PF coils are energized. When energizing, the PF1 coil and the PF2 coil, the PF2 coil and the PF3 coil, the PF3 coil and the PF4 coil, and the PF4 coil and the PF5 coil are energized at the same time so that the magnetic field generated by the coils can cover most of the magnetic probes to improve the signal-to-noise ratio; when energizing, the position of the magnetic probe and the position of the PF coil energized this time are measured by a laser tracker each time the power is turned on to obtain a measurement value, and a simulation value is obtained according to the relative spatial position of the pre-set PF coil and the magnetic probe, and the relative error between the simulation and the actual measurement is further obtained, and the measurement results of some of the magnetic probes are selected. The results are shown in Table 1:

[0028] Table 1. Schematic diagram of error percentages determined by measuring points using a laser tracker

[0029]

[0030] In Table 1, the simulation signal is obtained by the Green's function and the coil current; as shown in Table 1, the magnetic probes numbered 52 and 56 are located at the bottom of the vacuum chamber in the fusion device. When the laser tracker is used for measurement, the relative error of the magnetic probes at this location relative to the magnetic probes at other locations is significantly larger, which will have a significant impact on the accuracy of plasma equilibrium inversion; based on this, the laser tracker alone cannot be used to measure the magnetic probes located at the bottom of the vacuum chamber well.

[0031] To solve the above problems, according to an embodiment of the present invention, an embodiment of a method for measuring the position of a magnetic probe is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0032] In this embodiment, a method for measuring the position of a magnetic probe is provided, wherein the magnetic probe is installed in a vacuum chamber of a fusion device; Figure 3 is a flow chart of a method for measuring the position of a magnetic probe according to an embodiment of the present invention. Figure 3 As shown, the process includes the following steps:

[0033] Step S101: using a laser tracker to establish an absolute coordinate system of the vacuum chamber based on known preset position coordinates.

[0034] The measurement principle of the laser tracker is to obtain the distance information from the light-emitting part to the reflector by means of triangulation and other methods, and at the same time use an encoder and other devices to measure the laser emission angle information, and calculate the center coordinates of the spherical reflector by combining the distance information and the laser emission angle information; therefore, in this embodiment, a plurality of spherical reflectors can be pre-set at known preset positions in the vacuum chamber, and the center coordinates of the spherical reflector can be detected by a laser tracker, and further based on the center coordinates, an absolute coordinate system with the spherical center of the tokamak device as the origin is established as the absolute coordinate system of the vacuum chamber.

[0035] Step S102, using the same set of target points fixed in the vacuum chamber, the coordinate system of the multi-joint robot fixed in the vacuum chamber is converted into an absolute coordinate system.

[0036] As mentioned above, the laser tracker cannot measure the magnetic probe located at the bottom of the vacuum chamber well. To solve this problem, in the present invention, a multi-joint robot arm and a laser tracker are combined to jointly detect the position of the magnetic probe.

[0037] When a multi-joint robotic arm is being inspected, it usually uses its own fixed point as the coordinate origin for inspection, so it is necessary to convert the coordinate system of the multi-joint robotic arm itself into an absolute coordinate system in advance; based on this, in this embodiment, a laser tracker is first used to measure a group of target points fixed in a vacuum chamber to obtain a first target point coordinate value of the group of target points, and the absolute coordinate value is transmitted to the multi-joint robotic arm; at the same time, the multi-joint robotic arm is used to measure the group of target points to obtain a second target point coordinate value of the group of target points relative to the multi-joint robotic arm's own fixed point, and the coordinate system of the multi-joint robotic arm is further mapped to an absolute coordinate system using the difference between the first target point coordinate value and the second target point coordinate value.

[0038] Step S103 , measuring the position of the magnetic probe using a multi-joint robotic arm in the absolute coordinate system.

[0039] Exemplarily, the multi-joint robotic arm is used to detect the coordinates of the magnetic probe to determine the position of the magnetic probe; specifically, the multi-joint robotic arm can detect a fixed position on the magnetic probe housing and a random position on the housing surface; wherein, the fixed position can be set as a positioning hole on the surface of the magnetic probe housing; after the multi-joint robotic arm detects the above-mentioned fixed position and random position to obtain their coordinate values, the position of the magnetic probe can be determined by the coordinate values.

[0040] Exemplarily, in order to solve the problem that it is difficult for a laser tracker to measure the position of a magnetic probe located at the bottom of a vacuum chamber in a fusion device, as a possible implementation method, a multi-joint robotic arm at least detects the positions of multiple magnetic probes located at the bottom of the vacuum chamber; since the multi-joint robotic arm is disposed in the vacuum chamber, it can more accurately detect the position of the magnetic probe located at the bottom of the vacuum chamber by moving.

[0041] As another possible implementation method, a multi-joint robotic arm detects the position of each magnetic probe in the magnetic probe array; after obtaining the position coordinates of each magnetic probe, a weighted average can be performed with the position coordinates of the magnetic probe detected by a laser tracker to obtain the final position of the magnetic probe; wherein, when determining the position of each magnetic probe by weighted averaging, the detection errors of the laser tracker and the multi-joint robotic arm for the magnetic probe can be measured in advance, and their respective weights can be further determined based on the detection error; wherein the weight is inversely proportional to the detection error.

[0042] The above-mentioned method for measuring the position of the magnetic probe of the present invention utilizes a laser tracker to establish an absolute coordinate system of the vacuum chamber based on known preset position coordinates; utilizes the same set of targets fixed in the vacuum chamber to convert the coordinate system of a multi-joint robotic arm fixed in the vacuum chamber into an absolute coordinate system; utilizes the multi-joint robotic arm to measure the position of the magnetic probe in the absolute coordinate system; in the implementation method of using the multi-joint robotic arm to measure the position of the magnetic probe, the multi-joint robotic arm arranged in the vacuum chamber can more accurately detect the position of the magnetic probe located at the bottom of the vacuum chamber, thereby solving the technical problem of inaccurate detection of the position of the magnetic probe located at the bottom of the vacuum chamber in the method of using a laser tracker alone to detect the positioning holes on the surface of the magnetic probe to determine the position of the magnetic probe.

[0043] As an exemplary embodiment, the method of converting the coordinate system of a multi-joint robotic arm fixed in the vacuum chamber into an absolute coordinate system by using the same set of targets fixed in the vacuum chamber includes: using the laser tracker to measure first target coordinate values ​​of multiple targets fixed in the vacuum chamber in the absolute coordinate system; using the multi-joint robotic arm fixed inside the vacuum chamber to measure second target coordinate values ​​of multiple targets; and converting the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the first target coordinate values ​​and the second target coordinate values.

[0044] In this embodiment, since the multi-joint robotic arm is initially set up with its own fixed point as the coordinate origin; in order to convert the coordinate system of the multi-joint robotic arm into an absolute coordinate system with the center of the tokamak device as the origin, the laser tracker is first used to measure the first target coordinate values ​​of multiple targets fixed in the vacuum chamber in the absolute coordinate system, and then the multi-joint robotic arm fixed on the inside of the vacuum chamber is used to measure the second target coordinate values ​​of the multiple targets, so as to convert the coordinate system of the multi-joint robotic arm into the absolute coordinate system through the first target coordinate values ​​and the second target coordinate values.

[0045] As an exemplary embodiment, converting the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the first target coordinate value and the second target coordinate value includes: establishing the coordinate system of the multi-joint robotic arm using the fixed point of the multi-joint robotic arm as the coordinate origin; and converting the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the correspondence between the first target coordinate value and the second target coordinate value.

[0046] As an exemplary embodiment, the measuring of the position of the magnetic probe using the multi-joint robotic arm in the absolute coordinate system includes: using the multi-joint robotic arm to perform multi-point measurement of the magnetic probe to obtain absolute coordinate values ​​of the multi-point positions of the magnetic probe in the absolute coordinate system; and calculating the position information of the magnetic probe based on the absolute coordinate values ​​of the multi-point positions.

[0047] In the above implementation of the present embodiment, the position information of the magnetic probe can be calculated by measuring multiple points of the magnetic probe and obtaining the absolute coordinate values ​​of the multiple points in the absolute coordinate system.

[0048] As an exemplary embodiment, the multi-point measurement of the magnetic probe is performed using the multi-joint robotic arm to obtain absolute coordinate values ​​of the multi-point positions of the magnetic probe in an absolute coordinate system, including: using the multi-joint robotic arm to measure the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; the calculation of the position information of the magnetic probe based on the absolute coordinate values ​​of the multi-point positions includes: calculating the geometric center coordinate value of the magnetic probe according to the first absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe outer shell.

[0049] In this embodiment, the fixed position on the shell surface can be pre-set; as a possible implementation method, the fixed position on the shell surface can be a screw hole on the surface of the magnetic probe shell; as another possible implementation method, the fixed position on the shell surface can be a mark fixed on the surface of the component, and the fixed mark can be a position with a protrusion, depression, etc. on the shell surface, or a fixed position pre-set on the skeleton of the magnetic probe array.

[0050] The multi-joint robotic arm is used to measure the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; the point coordinates measured by the first absolute coordinate value and the second absolute coordinate value are the spherical center coordinates of its probe, and further, the geometric center coordinate value of the magnetic probe is calculated according to the first absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe outer shell; wherein N and M are both positive integers, and the sum of N and M is greater than 4, and the fixed position can be a positioning hole on the surface of the magnetic probe.

[0051] Since the point coordinates measured by the multi-joint robotic arm during measurement are the coordinates of the center of the sphere of its probe, and the position of the magnetic probe is usually the coordinates of its geometric center, therefore, after using the multi-joint robotic arm to perform multi-point measurement on the magnetic probe and obtain the absolute coordinate values ​​of the multi-point positions of the magnetic probe in the absolute coordinate system, it is necessary to further transform the absolute coordinate system based on the multi-point positions of the magnetic probe in the absolute coordinate system to obtain the geometric center coordinates of the magnetic probe; based on this, as an exemplary embodiment, the geometric center coordinate value of the spatial position of the magnetic probe calculated according to the first absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe housing includes: the calculation according to the first absolute coordinate value Calculating the geometric center coordinate value of the spatial position of the magnetic probe based on an absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe shell includes: averaging the first absolute coordinate value and projecting it to the shell surface of the magnetic probe to obtain the projection point position coordinate value of the shell surface; averaging and projecting the second absolute coordinate value to obtain the surface center coordinates of each shell surface; calculating the normal vector of the shell surface of the magnetic probe using the second absolute coordinate value or using the projection point position coordinate value and the second absolute coordinate value; determining the geometric center coordinate value according to the projection point position coordinate value of the shell surface, the shell surface normal vector and the shell size parameters.

[0052] In this embodiment, the size parameters of the shell include the thickness value of the shell and the relative position parameters of the fixed position on the shell relative to the center coordinates of the shell surface; exemplarily, the relative position parameters can be pre-calculated after determining the fixed position; therefore, in this embodiment, after obtaining the first absolute coordinate value, the average is first taken based on the first coordinate value, and then the averaged first absolute coordinate value and the relative position parameters of the fixed position on the shell relative to the center coordinates of the shell surface can be projected onto the shell surface of the magnetic probe to obtain the projection point position coordinate value, so as to obtain the coordinates of the center of the magnetic probe surface.

[0053] Exemplarily, after obtaining the second absolute coordinate value, since the second absolute coordinate value is located on the surface of the magnetic probe, the normal vector of the outer shell surface of the magnetic probe can be calculated using the second absolute coordinate value or using the projection point position coordinate value and the second absolute coordinate value.

[0054] Furthermore, the distance of the center coordinate of the shell surface of the magnetic probe along the normal vector toward the geometric center of the magnetic probe is half the thickness of the shell of the magnetic probe; based on this, the geometric center coordinate value can be determined according to the projection point position coordinate value of the shell surface, the normal vector of the shell surface and the thickness value of the shell in the shell size parameters, and the geometric center coordinate value represents the position of the magnetic probe in the vacuum chamber.

[0055] As another possible implementation method, the dimensional parameters of the shell include the thickness of the shell, and the first absolute coordinate values ​​of at least N fixed positions on the shell are four positioning holes pre-set on the shell in a rectangular shape on the shell surface, and the geometric center of the rectangle is the geometric center of the shell surface; exemplarily, after obtaining the first absolute coordinate values ​​of the four positioning holes and the second absolute coordinate values ​​of at least M random positions on the shell surface, the first absolute coordinate values ​​are averaged, and projected onto the surface of the magnetic probe shell to obtain the geometric center coordinates of the magnetic probe surface; further, after obtaining the second absolute coordinate value, since the second absolute coordinate value is located on the surface of the magnetic probe, the normal vector of the shell surface of the magnetic probe can be calculated using the second absolute coordinate value or the projection point position coordinate value and the second absolute coordinate value, and the distance of the center coordinate of the shell surface of the magnetic probe along the normal vector to the geometric center direction of the magnetic probe is half of the thickness of the magnetic probe shell; based on this, the geometric center coordinate value can be determined according to the projection point position coordinate value of the shell surface, the normal vector of the shell surface and the shell thickness value in the shell dimensional parameters, and the geometric center coordinate value represents the position of the magnetic probe in the vacuum chamber.

[0056] The magnetic probes in the magnetic probe array are not only arranged at a certain position in the vacuum chamber, but also arranged at a certain inclination; therefore, as an exemplary embodiment, the position information also includes the inclination of the magnetic probe in space, and the position information of the magnetic probe is calculated based on the absolute coordinate values ​​of multiple points, and also includes: calculating the angle between the normal vector of each shell surface and the normal vector of the horizontal plane; wherein the horizontal plane normal vector is determined by the absolute coordinate system; projecting the normal vector of the shell surface to the plane of the magnetic probe array, and obtaining the reference direction of the angle based on a preset reference direction; and determining the inclination based on the angle and the reference direction.

[0057] In this embodiment, the inclination is determined by the angle between each magnetic probe and the horizontal direction and the direction of the angle; illustratively, Figure 4 is a schematic diagram of the position of a magnetic probe in the vacuum chamber space, such as Figure 4 As shown, in this embodiment, the angle to be calculated is Figure 4 The angle β in the figure is represented by the angle between the normal vector of the shell surface and the normal vector of the horizontal plane z=(0,0,1). Based on this, the angle between the normal vector and the normal vector of the horizontal plane can be calculated according to formula (1).

[0058] (1)

[0059] In formula (1), a and b are vectors , The model, represents the surface normal vector of the magnetic probe, represents the normal vector of the horizontal plane, and β represents the angle between the normal vector of the shell surface and the normal vector of the horizontal plane.

[0060] Further, Figure 5 is a schematic diagram of a preset reference direction according to an embodiment of the present invention, such as Figure 5 As shown, in the present invention, the right side of the horizontal plane normal vector is defined as positive, and the left side is defined as negative, that is, the cross product vector of the magnetic probe surface normal vector of the midplane and the horizontal plane normal vector z=(0,0,1) is selected. The direction is positive, and the surface normal vector is The angle direction of the magnetic probes with an angle less than or equal to 90° is positive, and the angle direction of the magnetic probes with an angle greater than 90° is negative, so that the angle direction of each magnetic probe is obtained based on the preset reference direction, and then the inclination is determined based on the angle and the angle direction.

[0061] In a second aspect, the present invention provides a system for measuring the position of a magnetic probe, wherein the magnetic probe is installed in a vacuum chamber of a fusion device; the measurement system includes a laser tracker and a multi-joint robotic arm, wherein the laser tracker is arranged on the outside of the vacuum chamber, and the laser tracker establishes an absolute coordinate system of the vacuum chamber based on preset position coordinates; the multi-joint robotic arm is fixed on the inside of the vacuum chamber, and the laser tracker and the multi-joint robotic arm measure the coordinate values ​​of the same group of multiple target points to convert the coordinate system of the multi-joint robotic arm into an absolute coordinate system; the multi-joint robotic arm measures the position of the magnetic probe in the absolute coordinate system to obtain the position information of the magnetic probe.

[0062] In this embodiment, multiple spherical reflectors can be pre-set at known preset positions in the vacuum chamber, and the central coordinates of the spherical reflectors can be detected by a laser tracker to establish an absolute coordinate system with the spherical center of the tokamak device as the origin as the absolute coordinate system of the vacuum chamber.

[0063] When a multi-joint robotic arm is being inspected, it usually uses its own fixed point as the coordinate origin for inspection, so it is necessary to convert the coordinate system of the multi-joint robotic arm itself into an absolute coordinate system in advance; based on this, in this embodiment, the laser tracker measures a group of target points fixed in the vacuum chamber, obtains the first target point coordinate value of the group of target points, and transmits the absolute coordinate value to the multi-joint robotic arm; at the same time, the multi-joint robotic arm measures the group of target points, obtains the second target point coordinate value of the group of target points relative to the multi-joint robotic arm's own fixed point, and further converts the coordinate system of the multi-joint robotic arm into an absolute coordinate system based on the absolute coordinate value and the relative coordinate value.

[0064] In order to solve the problem that it is difficult for a laser tracker to measure the position of a magnetic probe located at the bottom of a vacuum chamber in a fusion device, as a possible implementation method, a multi-joint robotic arm at least detects the positions of multiple magnetic probes located at the bottom of the vacuum chamber; since the multi-joint robotic arm is arranged in the vacuum chamber, it can more accurately detect the position of the magnetic probe located at the bottom of the vacuum chamber by moving.

[0065] As another possible implementation method, a multi-joint robotic arm detects the position of each magnetic probe in the magnetic probe array; after obtaining the position coordinates of each magnetic probe, a weighted average can be performed with the position coordinates of the magnetic probe detected by a laser tracker to obtain the final position of the magnetic probe; wherein, when determining the position of each magnetic probe by weighted averaging, its weight can be determined by the detection errors of the laser tracker and the multi-joint robotic arm for the magnetic probe measured in advance, and the weight is inversely proportional to the detection error.

[0066] In the above-mentioned embodiment of the present invention, the laser tracker establishes an absolute coordinate system of the vacuum chamber based on known preset position coordinates; the laser tracker can use the same set of targets fixed in the vacuum chamber to convert the coordinate system of the multi-joint robotic arm fixed in the vacuum chamber into an absolute coordinate system; the multi-joint robotic arm measures the position of the magnetic probe in the absolute coordinate system; in the embodiment of measuring the position of the magnetic probe using the multi-joint robotic arm, the multi-joint robotic arm arranged in the vacuum chamber can more accurately detect the position of the magnetic probe located at the bottom of the vacuum chamber, which solves the technical problem of inaccurate detection of the position of the magnetic probe located at the bottom of the vacuum chamber in the method of using a laser tracker alone to detect the positioning holes on the surface of the magnetic probe to determine the position of the magnetic probe.

[0067] As an exemplary embodiment, the magnetic probe position measurement system also includes a data processing device, which is respectively connected to the laser tracker and the multi-joint robotic arm, and is used to collect measurements of the laser tracker and the multi-joint robotic arm; the laser tracker measures the first target point coordinate values ​​of multiple targets fixed inside the vacuum chamber in the absolute coordinate system; the multi-joint robotic arm measures the second target point coordinate values ​​of the multiple targets; and the data processing device converts the coordinate system of the multi-joint robotic arm into the absolute coordinate system based on the first target point coordinate values ​​and the second target point coordinate values.

[0068] As an exemplary embodiment, the multi-joint robotic arm measures the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; the data processing device calculates the geometric center coordinate value of the magnetic probe and the angle parameters between the surface of the magnetic probe and the horizontal plane based on the first absolute coordinate value and the second absolute coordinate value.

[0069] In this embodiment, the fixed position on the shell surface can be pre-set; as a possible implementation method, the fixed position on the shell surface can be a screw hole on the surface of the magnetic probe shell; as another possible implementation method, the fixed position on the shell surface can be a mark fixed on the surface of the component, and the fixed mark can be a position with protrusions, depressions, etc. on the shell surface.

[0070] The multi-joint robotic arm is used to measure the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; the point coordinates measured by the first absolute coordinate value and the second absolute coordinate value are the spherical center coordinates of its probe, and further, the geometric center coordinate value of the magnetic probe is calculated according to the first absolute coordinate value, the second absolute coordinate value and the size parameters of the magnetic probe outer shell; wherein N and M are both positive integers, and the sum of N and M is greater than 4, and the fixed position can be a positioning hole on the surface of the magnetic probe.

[0071] As a specific application embodiment of the present invention, the magnetic probe is installed in the vacuum chamber of the fusion device, and the measurement system includes a laser tracker and a multi-joint robotic arm, wherein the laser tracker is arranged on the outside of the vacuum chamber, and the laser tracker establishes an absolute coordinate system of the vacuum chamber based on preset position coordinates; the multi-joint robotic arm is fixed on the inside of the vacuum chamber, and the laser tracker and the multi-joint robotic arm measure the coordinate values ​​of the same group of multiple targets to convert the coordinate system of the multi-joint robotic arm into an absolute coordinate system; the multi-joint robotic arm measures the position of the magnetic probe in the absolute coordinate system to obtain the position information of the magnetic probe; the measurement method of the magnetic probe includes:

[0072] Step S201, using a laser tracker to detect known preset position coordinates to establish an absolute coordinate system with the center of the tokamak sphere in the vacuum chamber as the coordinate origin;

[0073] Step S202, using the laser tracker to measure the coordinate values ​​of the first target points of the plurality of target points fixed in the vacuum chamber in the absolute coordinate system, and transmitting the coordinate values ​​of the first target points to the multi-joint robotic arm;

[0074] Step S203, using a multi-joint robotic arm fixed inside the vacuum chamber to measure the coordinate values ​​of the second target points of the plurality of target points;

[0075] Step S204, converting the coordinate system of the multi-joint robotic arm into an absolute coordinate system using the first target point coordinate value and the second target point coordinate value;

[0076] Step S205, in an absolute coordinate system, using the multi-joint robotic arm to perform multi-point measurement of the magnetic probe, using the coordinates of the four screw holes on the surface of each magnetic probe shell and the coordinates of several points on the surface of each magnetic probe shell as measurement points, to obtain the first absolute coordinate values ​​of the four screw holes on the surface of each magnetic probe shell and the second absolute coordinate values ​​of several points on the surface of each magnetic probe shell of the multi-point position of the magnetic probe in the absolute coordinate system;

[0077] Step S206, taking an average of the first absolute coordinate values ​​of the four screw holes on the shell surface and projecting the average value onto the shell surface of the magnetic probe to obtain the position coordinate value of the projection point on the shell surface;

[0078] Step S207 , averaging and projecting the second absolute coordinate values ​​of several points on the surface of each magnetic probe shell to obtain the surface center coordinates of each shell surface.

[0079] Step S208: Calculate the normal vector of the outer shell surface of the magnetic probe by using the second absolute coordinate value or by using the projection point position coordinate value and the second absolute coordinate value.

[0080] Step S209 , adding the surface center coordinates of each shell surface to half of the thickness in the direction of its surface normal vector to obtain the geometric center coordinates of the magnetic probe.

[0081] Step S210, calculating the angle between each normal vector and the horizontal plane normal vector according to formula (1).

[0082] Step S211, projecting the normal vector of the shell surface onto the plane of the magnetic probe array, and obtaining the reference direction of the angle based on a preset reference direction;

[0083] Step S212: determining the inclination of the magnetic probe according to the included angle and the reference direction.

[0084] Exemplarily, first, five PF coils numbered PF1 to PF5 are pre-set in a vacuum chamber, and the set PF coils are energized. When energizing, the PF1 coil and the PF2 coil, the PF2 coil and the PF3 coil, the PF3 coil and the PF4 coil, and the PF4 coil and the PF5 coil are energized at the same time so that the magnetic field generated by the coils can cover most of the magnetic probes to improve the signal-to-noise ratio; when energizing, the above-mentioned magnetic probe measurement method of the present application is used to measure the position of the magnetic probe and the position of the PF coil energized this time at each power-on to obtain a measured value, and a simulation value is obtained based on the relative spatial position of the pre-set PF coil and the magnetic probe, and the relative error between the simulation and the actual measurement is further obtained, and the measurement results of some of the magnetic probes are selected. The obtained results are shown in Table 2:

[0085] Table 2. Schematic diagram of error percentages determined by measuring points using a multi-joint robotic arm

[0086]

[0087] It can be seen from Table 2 that when the magnetic probe measurement is performed using a multi-joint robotic arm, compared with the laser tracker, the multi-joint robotic arm arranged in the vacuum chamber can more accurately detect the positions of the magnetic probes numbered 52 and 56 located at the bottom of the vacuum chamber.

[0088] In this embodiment, as a possible implementation method, the multi-joint robotic arm at least detects the positions of multiple magnetic probes located at the bottom of the vacuum chamber; since the multi-joint robotic arm is arranged in the vacuum chamber, it can more accurately detect the positions of the magnetic probes located at the bottom of the vacuum chamber by moving.

[0089] As another possible implementation method, a multi-joint robotic arm detects the position of each magnetic probe in the magnetic probe array; after obtaining the position coordinates of each magnetic probe, a weighted average can be performed with the position coordinates of the magnetic probe detected by a laser tracker to obtain the final position of the magnetic probe; wherein, when determining the position of each magnetic probe by weighted averaging, the detection errors of the laser tracker and the multi-joint robotic arm for the magnetic probe can be measured in advance, and their respective weights can be further determined based on the measured detection errors; wherein the weight is inversely proportional to the detection error.

[0090] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0091] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for measuring the position of a magnetic probe, characterized in that: The magnetic probe is installed in the vacuum chamber of the fusion device, and the measuring method includes: Using a laser tracker to establish an absolute coordinate system of the vacuum chamber based on known preset position coordinates; Using the same set of targets fixed in the vacuum chamber, converting the coordinate system of the multi-joint robot fixed in the vacuum chamber into an absolute coordinate system; and Measuring the position of the magnetic probe using the multi-joint mechanical arm in the absolute coordinate system comprises the following steps: Projecting the first absolute coordinate value after averaging and the relative position parameter of the fixed position on the shell relative to the center coordinate of the shell surface onto the shell surface of the magnetic probe to obtain the projection point position coordinate value; The normal vector of the outer shell surface of the magnetic probe is calculated using the second absolute coordinate value or using the projection point position coordinate value and the second absolute coordinate value; wherein the first absolute coordinate value and the second absolute coordinate value are obtained by measuring the outer shell surface of the magnetic probe using the multi-joint robotic arm to obtain the first absolute coordinate values ​​of at least N fixed positions on the outer shell and the second absolute coordinate values ​​of at least M random positions on the outer shell surface; The geometric center coordinate value of the magnetic probe is determined according to the projection point position coordinate value of the shell surface, the normal vector of the shell surface and the shell thickness value in the shell size parameter. The geometric center coordinate value represents the position of the magnetic probe in the vacuum chamber.

2. The method for measuring the position of a magnetic probe according to claim 1, characterized in that: The method of converting the coordinate system of the multi-joint robot fixed in the vacuum chamber into an absolute coordinate system by using the same set of target points fixed in the vacuum chamber comprises: Using the laser tracker to measure the coordinate value of a first target point of a plurality of target points fixed in the vacuum chamber in the absolute coordinate system; Measuring the coordinate values ​​of the second target points of the plurality of target points by using the multi-joint robot arm fixed inside the vacuum chamber; The coordinate system of the multi-joint robot arm is converted into the absolute coordinate system based on the first target point coordinate value and the second target point coordinate value.

3. The method for measuring the position of a magnetic probe according to claim 2, characterized in that: The converting the coordinate system of the multi-joint robot arm into the absolute coordinate system based on the first target point coordinate value and the second target point coordinate value comprises: Establishing a coordinate system of the multi-joint robotic arm by taking the fixed point of the multi-joint robotic arm as the coordinate origin; Based on the correspondence between the first target point coordinate value and the second target point coordinate value, the coordinate system of the multi-joint robotic arm is converted into an absolute coordinate system.

4. The method for measuring the position of a magnetic probe according to claim 1, characterized in that: The measuring of the position of the magnetic probe by using the multi-joint mechanical arm in the absolute coordinate system comprises: Using the multi-joint mechanical arm to measure multiple points of the magnetic probe, and obtaining absolute coordinate values ​​of the multiple points of the magnetic probe in an absolute coordinate system; The position information of the magnetic probe is calculated based on the absolute coordinate values ​​of the multiple points.

5. The method for measuring the position of a magnetic probe according to claim 4, characterized in that: The position information also includes the inclination of the magnetic probe in space, and the position information of the magnetic probe is calculated based on the absolute coordinate values ​​of multiple points, and further includes: Calculating the angle between the normal vector of each shell surface and the normal vector of the horizontal plane; wherein the normal vector of the horizontal plane is determined by the absolute coordinate system; Projecting the normal vector of the shell surface onto the plane of the magnetic probe array, and obtaining the reference direction of the angle based on a preset reference direction; The inclination is determined based on the angle and the reference direction.

6. A magnetic probe position measurement system, characterized in that: The magnetic probe is installed in the vacuum chamber of the fusion device, and the measurement system includes a laser tracker and a multi-joint mechanical arm, wherein: The laser tracker is arranged outside the vacuum chamber, and the laser tracker establishes an absolute coordinate system of the vacuum chamber based on preset position coordinates; The multi-joint robotic arm is fixed to the inner side of the vacuum chamber, and the laser tracker and the multi-joint robotic arm measure the coordinate values ​​of the same group of multiple target points to convert the coordinate system of the multi-joint robotic arm into an absolute coordinate system; The multi-joint mechanical arm measures the position of the magnetic probe in the absolute coordinate system to obtain the position information of the magnetic probe; The multi-joint robotic arm is also used to: project the averaged first absolute coordinate value and the relative position parameters of the fixed position on the shell relative to the center coordinate of the shell surface to the shell surface of the magnetic probe to obtain the projection point position coordinate value, so as to obtain the coordinates of the center of the magnetic probe surface; calculate the normal vector of the shell surface of the magnetic probe using the second absolute coordinate value or using the projection point position coordinate value and the second absolute coordinate value; wherein the first absolute coordinate value and the second absolute coordinate value are obtained by measuring the shell surface of the magnetic probe using the multi-joint robotic arm to obtain the first absolute coordinate values ​​of at least N fixed positions on the shell and the second absolute coordinate values ​​of at least M random positions on the shell surface; determine the geometric center coordinate value according to the projection point position coordinate value of the shell surface, the normal vector of the shell surface and the shell thickness value in the shell size parameters, and the geometric center coordinate value represents the position of the magnetic probe in the vacuum chamber.

7. The magnetic probe position measurement system according to claim 6, characterized in that: Also included is a data processing device, connected to the laser tracker and the multi-joint robotic arm, respectively, for collecting measurements of the laser tracker and the multi-joint robotic arm; The laser tracker measures the coordinate value of a first target point of a plurality of target points fixed inside the vacuum chamber in the absolute coordinate system; The multi-joint robotic arm measures the coordinate values ​​of the second target points of the plurality of targets; The data processing device converts the coordinate system of the multi-joint robot arm into the absolute coordinate system based on the first target point coordinate value and the second target point coordinate value.

8. The magnetic probe position measurement system according to claim 7, characterized in that: The multi-joint mechanical arm measures the outer shell surface of the magnetic probe to obtain first absolute coordinate values ​​of at least N fixed positions on the outer shell and second absolute coordinate values ​​of at least M random positions on the outer shell surface; The data processing device calculates the geometric center coordinate value of the magnetic probe and the angle parameter between the surface of the magnetic probe and the horizontal plane based on the first absolute coordinate value and the second absolute coordinate value.

Images