Positioning device and positioning method based on rotational symmetry component

Abstract

The invention discloses a positioning device and a positioning method based on a rotational symmetry component, and belongs to the technical field of positioning detection, the positioning device comprises a workbench, an xy translation table, a placement table, a measuring instrument, a first theodolite and a second theodolite, the xy translation table can translate along x and y directions; the placing table is used for placing a to-be-tested rotational symmetry component, is arranged on the xy translation table, can translate along the x and y directions, and can horizontally rotate relative to the xy translation table; the measuring instrument is used for measuring the distance L and the rotation angle omega; and the first theodolite and the second theodolite are respectively used for measuring the rotational symmetry component to be measured. According to the positioning method, the position of the component is adjusted through the xy translation table and the placement table by taking a distance measurement result obtained by rotating the placement table for a circle as an adjustment basis and taking alignment of a datum line of a view field of the theodolite and a to-be-measured point as a basis. According to the invention, fixed-point detection can be carried out on the rotationally symmetrical component, the positioning difficulty is reduced, rapid calibration is carried out, and the positioning precision and the positioning efficiency can be obviously improved.

Description

Technical Field

[0001] The present application belongs to the field of positioning detection technology, and in particular relates to a positioning device and a positioning method based on a rotationally symmetric component. Background Art

[0002] Thanks to the powerful penetration of neutron radiation into materials, neutron diffraction is currently the only experimental method that can non-destructively obtain information about the internal, deep crystal structure of a material. The neutron stress measurement method developed based on this technique can non-destructively and deeply determine the three-dimensional stress distribution within a material, making it the only non-destructive stress measurement method for material components. Residual stress is crucial to engineering quality and service reliability, and remains a highly sought-after and challenging issue in related fields. Due to its advantages, neutron stress measurement technology is more closely linked to engineering problems and is therefore internationally recognized as having great application value in the engineering field. The principle of neutron stress measurement is to measure the shift in the position of the lattice diffraction peak, calculate the strain value using Bragg's law, and then further determine the stress magnitude using the generalized Hooke's law. By measuring the change in the diffraction peak position at different locations on the component, the stress distribution can be obtained through conversion. During measurement, both the incident neutron beam and the diffracted neutron beam are confined to millimeter or submillimeter beam lines through a neutron slit. The intersection of the two beams is the location of the neutron beam spot, which is also the stress measurement point. Due to the particularity of the neutron source, the neutron optical path cannot usually be changed during the test of the specimen, so the component itself must be moved to switch the detection point. Before measurement, it is necessary to use optical methods to determine the relative position relationship between the neutron beam spot and the point to be measured on the component. This process is called sample positioning and is an important part of the implementation of neutron stress detection. The deviation from the initial positioning will lead to a significant deviation of the detection point after the specimen is moved over a large range, causing distorted results. Traditionally, methods such as plumb bobs, lasers, and theodolite observations are used to determine whether the positioning is complete by the human eye. This process requires repeated placement of samples, and the time consumed is usually on the order of hours. In addition, the judgment standards of the human eye are different, and there is a strong degree of subjectivity and experience, making it difficult to guarantee positioning accuracy. Therefore, there is an urgent need for methods to improve positioning accuracy and efficiency.

[0003] The existing technology also has the above-mentioned problems for the positioning detection of rotationally symmetrical components. Rotationally symmetrical components have a component shape that is extremely widely used in engineering. For example, important components such as aircraft engine turbine disks, nuclear power pressure vessels, rail transit wheel discs, and oil pipelines all have a rotationally symmetrical appearance. The geometrically equivalent points of such components are distributed around the symmetry axis. Therefore, stress detection of a certain area of ​​interest is usually arranged around the symmetry axis to compare the results. This requires the sample to rotate during the detection process. Usually, such workpieces are directly placed on a rotating fixture, and the coincidence of the workpiece symmetry axis and the turntable axis is determined by optical positioning. However, the accuracy of the traditional positioning method of optical assistance combined with human eye judgment is usually in the sub-millimeter level. When the specimen is rotated through a large angle, either the accuracy of the measurement point position needs to be rechecked, which will affect the measurement efficiency, or the measurement point position will be offset, which will affect the accuracy of the measurement result. Summary of the Invention

[0004] The present application aims to solve the technical problem of positioning detection of rotationally symmetrical components. To this end, the present application provides a positioning device and positioning method based on rotationally symmetrical components, which can perform fixed-point detection of rotationally symmetrical components, reduce the positioning difficulty, enable rapid calibration, and significantly improve positioning accuracy and positioning efficiency.

[0005] In a first aspect, an embodiment of the present application provides a positioning device based on a rotationally symmetric component, comprising:

[0006] a workbench to provide support;

[0007] An xy translation stage, which can be translated relative to the workbench along the x direction and the y direction, where x and y are two different horizontal directions respectively;

[0008] A placement table is used to place the rotationally symmetrical component to be measured. The placement table is arranged on the xy translation table. The placement table can be translated relative to the xy translation table along the x and y directions, and the placement table can be horizontally rotated relative to the xy translation table.

[0009] A measuring instrument, used to measure the distance L between itself and the surface of the rotationally symmetrical component to be measured, and the horizontal rotation angle ω of the rotationally symmetrical component to be measured, and the measuring instrument is fixed to the xy translation stage;

[0010] The first theodolite and the second theodolite form a triangle with the position of the placement platform, and are used to measure the rotationally symmetrical component to be measured on the placement platform from two horizontal directions.

[0011] In some embodiments, a support platform and a lifting rod are further included, each corresponding to the first theodolite and the second theodolite. The support platform is used to support the first theodolite or the second theodolite, and the lifting rod is used to adjust the height of the first theodolite and the second theodolite. The two ends of the lifting rod are respectively connected to the first theodolite and the support platform, and the two ends of the other lifting rod are respectively connected to the second theodolite and the other support platform.

[0012] In some embodiments, a reference stage is further included, which is fixed to the xy translation stage and is used to install the placement stage, so that the placement stage can rotate horizontally relative to the reference stage and can translate along the x direction and the y direction.

[0013] In a second aspect, an embodiment of the present application provides a positioning method based on a rotationally symmetric component, which uses the positioning device based on the rotationally symmetric component as described above. The positioning method includes:

[0014] Adjust the height and angle of the first theodolite and the second theodolite so that the center mark of the xy translation stage is located on the vertical reference line of the field of view of the first theodolite and the second theodolite, and then adjust the elevation angle of the first theodolite and the second theodolite to zero;

[0015] Mark the test points on the surface of the rotationally symmetrical component to be tested, place the rotationally symmetrical component to be tested on a placement table, and ensure that the symmetry axis of the rotationally symmetrical component to be tested is perpendicular to the table surface of the placement table;

[0016] Rotate the stage horizontally for at least one revolution while recording L and ω. Based on the relationship between L and ω, determine the position (x0, y0) of the axis of symmetry of the rotationally symmetrical component to be measured in the coordinate system formed by the x- and y-directions.

[0017] According to the position (x0, y0), adjust the position of the placement table along the x-direction and the y-direction so that the symmetry axis of the rotationally symmetrical component to be measured returns to zero;

[0018] Adjust the height of the workbench so that the horizontal reference line of the field of view of the first theodolite or the second theodolite coincides with the point to be measured;

[0019] The position of the xy translation stage is adjusted along the x direction and the y direction so that the vertical reference line of the field of view of the first theodolite or the second theodolite coincides with the point to be measured.

[0020] In some embodiments, after adjusting the position of the placement table along the x-direction and the y-direction and before adjusting the height of the workbench, the method further includes the following steps:

[0021] Rotate the stage horizontally for at least one circle, record L and ω, and use curve fitting to determine the position of the symmetry axis (x0′, y0′) of the rotationally symmetric component to be measured;

[0022] According to the position (x0′, y0′), the position of the placement table is adjusted along the x-direction and the y-direction to return the symmetry axis of the rotationally symmetrical component to be measured to zero.

[0023] In some embodiments, the curve fitting method is to establish a trigonometric function relationship between L and ω.

[0024] In some embodiments, when determining the position (x0, y0), based on L and ω, the maximum distance L max and the corresponding rotation angle ω max , the measured closest distance L min , the rotation angle ω corresponding to the measured closest distance min , and establish trigonometric function relationships to solve them.

[0025] In some embodiments, after the horizontal reference line coincides with the point to be measured and the vertical reference line coincides with the point to be measured, the placement table is rotated horizontally for at least one circle, and L and ω are recorded; if L remains unchanged, the process ends; if L changes with ω, the steps after placing the rotationally symmetrical component to be measured on the placement table and before adjusting the height of the workbench are repeated.

[0026] In some embodiments, when the rotationally symmetrical component to be measured is placed on the placement table, ensure that the extension line of the distance measurement path of the measuring instrument passes through the rotation axis of the placement table.

[0027] In some embodiments, the method further includes adjusting the heights and angles of the first theodolite and the second theodolite so that the neutron beam height markers are both located at the central focus of the fields of view of the first theodolite and the second theodolite.

[0028] It can be seen from the above technical solution that the beneficial effects of this application are:

[0029] 1. The positioning device of the present application uses a workbench as a support, and places a rotationally symmetrical component to be measured on a placement table. The xy translation stage is translated in the x and y directions to adjust the xy translation stage to the vertical reference line of the field of view of the first theodolite and the second theodolite, so that the xy translation stage can be positioned from two directions by the first theodolite and the second theodolite. The placement stage is translated in the x and y directions and rotated horizontally to adjust the position and rotation angle of the placement stage relative to the xy translation stage. In this way, the measuring instrument can measure the distance L between itself and the surface of the rotationally symmetrical component to be measured and the horizontal rotation angle ω of the rotationally symmetrical component to be measured, so that whether it is adjusted in place can be determined by whether L changes with ω. Since the rotationally symmetrical component to be measured has multiple degrees of freedom on the placement table, and whether it is adjusted in place can be determined by rotation, fixed-point detection of the rotationally symmetrical component is achieved, which reduces the difficulty of positioning and helps to improve positioning accuracy and efficiency.

[0030] 2. The positioning method of the present application, by adjusting the field of view reference line of the first theodolite and the second theodolite to assist in judgment, can move the xy translation stage until the xy translation stage is located on the vertical reference line of the first theodolite and the second theodolite, ensuring that the xy translation stage is accurately positioned, and adjusting the elevation angle to zero so that positioning can be performed using the horizontal reference line of the field of view, placing the rotationally symmetrical component, and rotating the placement stage. In this way, according to the distance between the measuring instrument and the point to be measured and the rotation angle of the placement stage, the relationship between L and ω can be obtained, and then the coordinates of the actual rotationally symmetrical axis of the component can be determined, and then the symmetry axis is reset to zero, and the position of the placement stage is adjusted. By adjusting the workbench height and adjusting the xy translation stage, the horizontal reference line and the vertical reference line are made to coincide with the point to be measured, thus completing the movement of the rotationally symmetrical component to the detection position. By utilizing the relationship between L and ω, it is possible to quickly determine whether the adjustment is in place, realize fixed-point detection of the rotationally symmetrical component, and perform rapid calibration, which can significantly improve positioning accuracy and positioning efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments one by one. Obviously, the drawings described below are some embodiments of the present application. For those of ordinary skill in the art, other embodiments and drawings can be obtained based on these drawings without inventive work. Various schematic diagrams according to the embodiments of the present application are shown in the drawings. These drawings are not necessarily drawn to scale. For the purpose of clarity, some details are magnified and some details may be omitted.

[0032] Figure 1 A schematic diagram of an embodiment of a positioning device based on a rotationally symmetrical component of the present invention is shown;

[0033] Figure 2 Schematic diagram of an embodiment showing the reference line and central focus in the field of view of the first theodolite and the second theodolite of the present invention;

[0034] Figure 3 A schematic diagram of an embodiment of the table top and center mark of the xy translation stage of the present invention is shown;

[0035] Figure 4 A schematic diagram of an embodiment of a positioning method based on a rotationally symmetrical component of the present invention is shown;

[0036] Figure 5 A top view schematically shows the positional relationship of an xy translation stage, a rotationally symmetrical component to be measured, and a measuring instrument according to an embodiment of the present invention;

[0037] Figure 6 The figure shows the relationship between the distance L measured by the laser interferometer rangefinder of the present invention and the rotation angle ω of the placement table.

[0038] Figure numerals: 1. workbench; 2. xy translation stage; 3. placement stage; 4. measuring instrument; 5. first theodolite; 6. second theodolite; 7. support platform; 8. lifting rod; 9. reference platform; 10. guide rail; 11. motor; 12. vertical reference line; 13. horizontal reference line; 14. central focus; 15. center mark; 16. neutron beam height mark; 17. rotationally symmetrical component to be measured; 18. point to be measured; 19. axis of symmetry. DETAILED DESCRIPTION

[0039] The following will be combined with the accompanying drawings corresponding to the specific embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. The following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection. The described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, various different configurations can be arranged and designed. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] The present application is described below with reference to specific embodiments and with reference to the accompanying drawings:

[0041] Please refer to Figure 1 The first embodiment of the present application provides a positioning device based on a rotationally symmetrical component, which includes: a workbench 1, an xy translation stage 2, a placement stage 3, a measuring instrument 4, a first theodolite 5, and a second theodolite 6. The workbench 1 is used to provide support. The workbench 1 is placed in the work area or experimental area. The top surface of the workbench 1 provides support and an operating area for the xy translation stage 2; the xy translation stage 2 can be translated relative to the workbench 1 along the x direction and the y direction, where x and y are two different horizontal directions. The xy translation stage 2 is plate-shaped, and the top surface provides support and an operating area for the placement table 3; in order to achieve translation in two different directions, two crossing guide rails 10 can be set on the surface of the workbench 1, one guide rail 10 is set along the x direction, and the other guide rail 10 is set along the y direction. One guide rail 10 can be fixed to the workbench 1, and the other guide rail 10 can be fixed to the bottom of the xy translation stage 2. Gaps can also be set at multiple locations of the two guide rails 10 so that the xy translation stage 2 can slide and match with the two guide rails 10. In this way, the xy translation stage 2 can be translated along both the x direction and the y direction. The realization of translation in two directions is a structure that can be achieved by the existing guide rails 10.

[0042] The placement table 3 is used to place the rotationally symmetrical component 17 to be tested. The top surface of the placement table 3 is horizontal and flat. The placement table 3 is set on the xy translation stage 2. The placement table 3 can translate relative to the xy translation stage 2 in the x and y directions. The placement table 3 can also rotate horizontally relative to the xy translation stage 2. In this way, the placement table 3 can translate in two directions and rotate horizontally. To achieve the above-mentioned movement of the placement table 3, two guide rails 10 can also be installed on the surface of the xy translation stage 2, with a structure similar to that between the xy translation stage 2 and the workbench 1. At the same time, bearings can be set at the bottom of the placement table 3, and the bearings can be snapped into the track grooves of the guide rails 10. In this way, the placement table 3 can achieve horizontal rotation through the bearings and can also translate in the x and y directions. The translation accuracy of the above-mentioned xy translation stage 2 and placement table 3 in the x and y directions is at least 10 microns.

[0043] The measuring instrument 4 is used to measure the distance L between itself and the surface of the rotationally symmetrical component 17 to be measured, and the horizontal rotation angle ω of the rotationally symmetrical component 17 to be measured. The measuring instrument 4 is fixed to the xy translation stage 2. The base of the measuring instrument 4 can be fixed to the surface of the xy translation stage 2 by screws. The measuring instrument 4 uses an instrument that can simultaneously measure distance and angle, such as a laser interferometer rangefinder, with a measurement accuracy of at least 5 microns. The first theodolite 5 and the second theodolite 6 form a triangle with the position line of the placement platform 3, that is, the three form a triangular relationship. The first theodolite 5 and the second theodolite 6 are respectively located at two different directions of the placement platform 3, and are respectively used to measure the rotationally symmetrical component 17 to be measured placed on the placement platform 3 from two horizontal directions. The first theodolite 5 and the second theodolite 6 can respectively use existing theodolites, and their fields of view have a vertical reference line 12 and a horizontal reference line 13, such as Figure 2 .

[0044] The existing technology for positioning detection of rotationally symmetrical components has the problems of difficulty in ensuring positioning accuracy and low positioning efficiency. This is because the existing device places the rotationally symmetrical component 17 to be measured, and traditionally uses methods such as plumb bobs, lasers, and theodolite observations to determine whether the positioning is complete by human eyes, and then performs neutron stress detection. However, human eye judgment often causes large errors, and manual adjustment of the position of the rotationally symmetrical component 17 to be measured is prone to repetition, making it difficult to adjust it into place. The present application utilizes a workbench 1 as a support, and places a rotationally symmetrical component 17 to be measured via a placement table 3. By translating the xy translation stage 2 along the x and y directions, the xy translation stage 2 can be adjusted to the vertical reference line 12 of the field of view of the first theodolite 5 and the second theodolite 6, thereby positioning the xy translation stage 2 from two directions via the first theodolite 5 and the second theodolite 6. By translating and horizontally rotating the placement stage 3 along the x and y directions, the position and rotation angle of the placement stage 3 relative to the xy translation stage 2 can be adjusted. In this way, the measuring instrument 4 can measure the distance L between itself and the surface of the rotationally symmetrical component 17 to be measured, and the horizontal rotation angle ω of the rotationally symmetrical component 17 to be measured, thereby determining whether it is adjusted into place by whether L changes with ω. Since the rotationally symmetrical component 17 to be measured has multiple degrees of freedom on the placement table 3, and whether it is adjusted into place can be determined by rotation, fixed-point detection of the rotationally symmetrical component is achieved, which reduces the difficulty of positioning and helps to improve positioning accuracy and efficiency.

[0045] In some embodiments, the positioning device further includes a support platform 7 and a lifting rod 8, both of which correspond to the first theodolite 5 and the second theodolite 6 one-to-one. The support platform 7 is placed or fixed on the ground, and the support platform 7 is used to support the first theodolite 5 or the second theodolite 6. The lifting rod 8 is used to adjust the height of the first theodolite 5 or the second theodolite 6. The two ends of the lifting rod 8 are respectively connected to the first theodolite 5 and the support platform 7, and the two ends of the other lifting rod 8 are respectively connected to the second theodolite 6 and the other support platform 7. For example, the two ends of the lifting rod 8 are respectively connected to the support platform 7, the first theodolite 5 or the second theodolite 6 by threaded connection, screw fixation or other methods. The lifting rod 8 adopts a rod-tube structure with two or more sections connected in a sleeve manner, such as lifting and lowering by extending one section or inserting one section into another section.

[0046] In some embodiments, the positioning device further includes a reference table 9, which is fixed to the xy translation stage 2. The reference table 9 is a plate structure of a certain thickness. The reference table 9 is fixed to the top surface of the xy translation stage 2 by screws and can translate along the x and y directions with the xy translation stage 2. The reference table 9 is used to mount the placement table 3, so that the placement table 3 can rotate horizontally relative to the reference table 9 and can translate along the x and y directions. The function of the placement table 3 can be achieved as follows: a guide rail 10 along the x and y directions is provided on the top of the reference table 9, and the bottom of the placement table 3 is connected to the guide rail 10. The installation method of the placement table 3 and the reference table 9 is the same as the installation method of the xy translation stage 2 and the workbench 1.

[0047] Please refer to Figure 3 In some embodiments, the positioning device further includes a bracket connected to the bottom of the support platform 7. The bracket can be a tripod and can provide stable support for the first theodolite 5 and the second theodolite 6. The center position of the above-mentioned xy translation stage 2 is further provided with a center mark 15. The center mark 15 is placed on the xy translation stage 2. The center mark 15 is used to facilitate positioning of the xy translation stage 2 during positioning. The center mark 15 can be set to a pointed shape to facilitate confirmation from the field of view of the first theodolite 5 and the second theodolite 6 during positioning. The bottom of the above-mentioned xy translation stage 2 and the placement platform The guide rails 10 provided at the bottom of the 3 are respectively provided with slide grooves, and the bottom of the xy translation stage 2 and the bottom of the placement stage 3 are placed in the slide grooves for matching, and the bottom of the xy translation stage 2 and the bottom of the placement stage 3 are threadedly connected to the lead screws placed in the slide grooves, so that the horizontal position of the xy translation stage 2 can be adjusted by twisting the end of the lead screw, and the placement stage 3 has the same arrangement; the above-mentioned guide rails 10 can be provided with a motor 11 at the end, such as the end of the lead screw can be connected to the output end of the motor 11 through a coupling or a key, so that the positions of the xy translation stage 2 and the placement stage 3 can be electrically adjusted in the x and y directions.

[0048] Please refer to Figure 4 In a second embodiment of the present application, a positioning method based on a rotationally symmetric component is provided. The positioning method adopts the positioning device based on the rotationally symmetric component as described above, and includes:

[0049] S1. Adjust the height and angle of the first theodolite 5 and the second theodolite 6. The height of the first theodolite 5 and the second theodolite 6 can be adjusted through the above-mentioned support platform 7 or lifting rod 8. Through the first theodolite 5 and the second theodolite 6, the center mark 15 of the xy translation stage 2 is located on the vertical reference line 12 of the field of view of the first theodolite 5 and the second theodolite 6 to achieve the initial positioning of the xy translation stage 2, and then adjust the elevation angle of the first theodolite 5 and the second theodolite 6 to zero. At this time, the intersection point of the fields of view of the adjusted first theodolite 5 and the second theodolite 6 is the location of the neutron beam spot, that is, the fixed point detection point. For the convenience of explanation, the first theodolite 5 and the second theodolite 6 are recorded as a double theodolite, such as Figure 4 middle.

[0050] S2. Select a rotationally symmetrical component, such as a cylinder or a conical table lamp, observe the appearance characteristics of the rotationally symmetrical component, and confirm whether it meets the rotational symmetry characteristics. If so, mark its symmetry axis 19. If a partial area of ​​the rotationally symmetrical component meets the rotational symmetry characteristics, mark the symmetry axis 19 of the part; confirm the area to be tested of the rotationally symmetrical component, and mark the test point 18 on the surface of the rotationally symmetrical component 17 to be tested, place the rotationally symmetrical component 17 to be tested on the placement table 3, ensure that the symmetry axis 19 of the rotationally symmetrical component 17 to be tested is perpendicular to the table surface of the placement table 3, and try to make the symmetry axis 19 of the rotationally symmetrical component 17 to be tested be located at the center of the table surface of the placement table 3, and ensure that the laser interferometer rangefinder is fixed next to the placement table 3, and the position setting is as follows Figure 5 .

[0051] S3. Rotate the placement table 3 horizontally for at least one circle, such as 360°. During the rotation process, simultaneously record the distance L from the rotationally symmetrical component measured by the rangefinder and the rotation angle ω of the placement table 3. Based on the relationship between L and ω, establish an equation. Use the central axis of the placement table 3 as the point of the circle, establish a coordinate system in the x- and y-directions, and determine the position (x0, y0) of the symmetry axis 19 of the rotationally symmetrical component 17 to be measured in the coordinate system formed by the x- and y-directions.

[0052] S4. According to the position (x0, y0), adjust the position of the placement table 3 along the x-direction and the y-direction to return the symmetry axis 19 of the rotationally symmetrical component 17 to be measured to zero, that is, use (-x0, -y0) as the adjustment amount, move the placement table 3 horizontally, and perform a rough adjustment on the rotationally symmetrical component, that is, translate the placement table 3 in the x-direction by a distance of -x0 and in the y-direction by a distance of -y0, and roughly adjust the symmetry axis 19 of the rotationally symmetrical component to coincide with the rotation axis of the placement table 3.

[0053] S5. Adjust the height of the workbench 1 and observe through the first theodolite 5 and the second theodolite 6 so that the horizontal reference line 13 of the field of view of the first theodolite 5 or the second theodolite 6 coincides with the point to be measured 18. In this way, the point to be measured 18 of the rotationally symmetrical component is adjusted to the expected horizontal position.

[0054] S6. Adjust the position of the xy translation stage 2 along the x-direction and the y-direction so that the vertical reference line 12 of the field of view coincides with the point to be measured 18 in the first theodolite 5 or the second theodolite 6. In this way, the point to be measured 18 of the rotationally symmetrical component is adjusted to the expected vertical position, thereby completing multi-directional precise positioning.

[0055] The existing technology has the problem of difficulty in ensuring the positioning accuracy and low positioning efficiency for the positioning detection of rotationally symmetrical components. This is because the existing methods traditionally use plumb bobs, lasers, and theodolite observations, and the human eye is used to judge whether the positioning is completed, and then neutron stress detection is performed. Although there are instruments involved in the existing methods, it is still judged by the human eye, which often causes large errors. In addition, manual adjustment of the position of the rotationally symmetrical component 17 to be measured is easy to be repeated, and it is difficult to adjust it into place. The present application assists in judgment by adjusting the field of view reference line of the first theodolite 5 and the second theodolite 6. The xy translation stage 2 can be moved until the xy translation stage 2 is located on the vertical reference line 12 of the first theodolite 5 and the second theodolite 6, ensuring that the xy translation stage 2 is accurately positioned, and the elevation angle is adjusted to zero so that the horizontal reference line 13 of the field of view can be used for positioning. The rotationally symmetrical component is placed, and the placement table 3 is rotated. In this way, according to the distance between the measuring instrument 4 and the point to be measured 18 and the rotation angle of the placement table 3, the relationship between L and ω can be obtained, and then the position of the rotationally symmetrical component 17 can be determined. The coordinates of the actual rotationally symmetrical axis 19 of the component are determined, and then the axis of symmetry 19 is reset to zero. The position of the placement table 3 is adjusted. By adjusting the height of the workbench 1 and the xy translation stage 2, the horizontal reference line 13 and the point to be measured 18 are made to coincide with each other, and the vertical reference line 12 and the point to be measured 18 are made to coincide with each other. In this way, the rotationally symmetrical component is moved to the detection position. The relationship between L and ω is used to quickly determine whether the adjustment is in place, thereby realizing fixed-point detection of the rotationally symmetrical component for rapid calibration, which can significantly improve positioning accuracy and efficiency.

[0056] Please refer to Figure 6 In some embodiments, in the above step S3, when determining the position (x0, y0), based on L max 、ω max , L min 、ω min The trigonometric function relationship equation (1) is established for calculation:

[0057]

[0058] Wherein, η is the angle between the extended line of the distance measurement path and the x-axis of the table surface on which the table 3 is placed.

[0059] In some embodiments, after adjusting the position of the placement table 3 along the x-direction and the y-direction and before adjusting the height of the workbench 1, the following steps are further included:

[0060] S41. Rotate the placement table 3 horizontally for at least one circle, such as 360°, while recording the distance L between the rangefinder and the rotationally symmetrical component and the rotation angle ω of the placement table 3. Use curve fitting to determine the position (x0′, y0′) of the symmetry axis 19 of the rotationally symmetrical component 17 to be measured, which is the precise coordinate.

[0061] S42. According to the position (x0′, y0′), adjust the position of the placement table 3 along the x-direction and the y-direction to return the symmetry axis 19 of the rotationally symmetrical component 17 to be measured to zero, that is, use (-x0′, -y0′) as the adjustment amount, move the placement table 3 horizontally, and perform fine adjustment on the rotationally symmetrical component.

[0062] This application achieves precise positioning relative to the detection point by performing multiple rounds of rough adjustment, fine adjustment, and review on the rotationally symmetrical component. Due to the use of a laser interferometer rangefinder, a placement table 3, and an xy translation table 2, the accuracy of the rangefinder and translation device can currently reach a few microns. This improves the positioning accuracy from the millimeter level to the micron level, greatly improving the accuracy of the coincidence between the symmetry axis 19 of the rotationally symmetrical component and the rotation axis of the placement table 3, achieving high-precision coincidence and calibration. By determining whether the adjustment is in place by rotating the placement table 3, the detection can be quickly achieved, and the positioning efficiency is increased from the hour level to the minute level, significantly improving the positioning efficiency. It is suitable for the scenario of axial neutron stress detection of components with rotationally symmetrical geometric shapes, and can also be extended to the axial rotation neutron diffraction stress non-destructive testing of other types of fixed points and their equivalent points of such components, or fixed-point detection scenarios using other radiation sources, achieving automatic calibration of product fixed-point detection, with the characteristics of fast and accurate detection.

[0063] In some embodiments, when determining the position (x0, y0), based on the distance L between the rangefinder and the rotationally symmetrical component and the rotation angle ω of the placement table 3, the maximum distance L measured is found. max and the corresponding rotation angle ω max , the measured closest distance L min , the rotation angle ω corresponding to the measured closest distance min , and establish a trigonometric function relationship to solve. In some embodiments, the curve fitting method is to establish a trigonometric function relationship between L and ω, such as equation (2):

[0064] L=a cosω+bsinω+c (2)

[0065] Where a, b, and c are fitted by Equation 2 Figure 6 The L-ω relationship shown here yields the fitting parameters.

[0066] The exact position (x0′, y0′) of the symmetry axis 19 of the rotationally symmetric member on the table surface of the placement table 3 is determined by the following equation (3):

[0067]

[0068] Wherein, η is the angle between the extended line of the distance measurement path and the x-axis of the table surface on which the table 3 is placed.

[0069] In some embodiments, after the horizontal reference line 13 coincides with the point to be measured 18 and the vertical reference line 12 coincides with the point to be measured 18, the placement table 3 is rotated horizontally for at least one circle, and L and ω are recorded at the same time to establish a relationship between the two; if L remains unchanged, the process ends, that is, the measured distance L does not change with the rotation angle ω of the placement table 3; if L changes with ω, the steps after placing the rotationally symmetrical component 17 to be measured on the placement table 3 and before adjusting the height of the workbench 1 are repeated, that is, the coarse adjustment, fine adjustment and adjustment of the xy translation stage 2 are repeated.

[0070] In some embodiments, when the rotationally symmetrical component 17 to be measured is placed on the placement table 3, ensure that the extension line of the distance measurement path of the measuring instrument 4 passes through the rotation axis of the placement table 3, so that the measuring instrument 4, the point to be measured 18 and the symmetry rotation axis of the placement table 3 are located on the same plane, and the initial adjustment setting makes the subsequent measurement of the measuring instrument 4 more accurate.

[0071] In some embodiments, the positioning method further includes adjusting the height and angle of the first theodolite 5 and the second theodolite 6 so that the neutron beam height marker 16 is located at the central focus 14 of the field of view of the first theodolite 5 and the second theodolite 6. The neutron beam height marker 16 is aligned with the central focus 14. After the positioning method is performed, the intersection of the fields of view of the first theodolite 5 and the second theodolite 6 is the location of the neutron beam spot, and the point to be measured 18 can be aligned with the neutron beam. This achieves precise positioning of the rotationally symmetrical component before neutron stress detection, significantly improving positioning efficiency and accuracy compared to traditional optical assistance and human visual judgment methods.

[0072] Regarding the specific implementation of this application, it should be noted that:

[0073] In the description of this application, unless otherwise clearly specified and limited, the terms "connect", "fixed", "connected", etc. should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral molding; "connection" can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly limited; "connected" can be the internal connection of two parts and between two parts, or the spatial connection between the two, and the two are directly or indirectly connected through the part that forms the space. The terms "set", "install", "provided with", "configured", etc. should also be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0074] In the description of this application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only used to facilitate the description of this application and simplify the description. They do not indicate or imply that the system or component referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting this application. All directional indications are only used to explain the relative positional relationships, movement conditions, etc. between the components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0075] In the description of this application, reference to the terms "some embodiments", "optional embodiments", "examples", "specific examples", "optional examples" or "optional embodiments" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this application, but does not mean that these embodiments illustrate and describe all possible forms of the invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0076] The present invention has been described in detail above with reference to specific embodiments and exemplary examples. The above description is illustrative, not exhaustive, and is not limited to the disclosed embodiments; the above description cannot be understood as a limitation of the present invention. The technical solutions between the various embodiments can be combined with each other, but must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application. Although the embodiments of the present application have been shown and described, these embodiments can be subjected to various changes, modifications, substitutions and variations without departing from the principles and purposes of the present application. Ordinary technicians in this field can understand that various other specific changes and combinations of embodiments that do not depart from the essence of the present application are made according to the technical inspirations disclosed in this application, and are still within the scope of protection defined by the claims of the present invention and its equivalent technical solutions.

Claims

1. A positioning device based on a rotationally symmetrical component, characterized in that: include: A workbench (1) for providing support; An xy translation stage (2) is translatable relative to the workbench (1) along an x ​​direction and a y direction, wherein x and y are two different horizontal directions respectively; A placement platform (3) is used to place a rotationally symmetrical component (17) to be measured, wherein the placement platform (3) is arranged on the xy translation platform (2), the placement platform (3) is translatable relative to the xy translation platform (2) along the x direction and the y direction, and the placement platform (3) is rotatable horizontally relative to the xy translation platform (2); a measuring instrument (4) for measuring a distance L between itself and a surface of a rotationally symmetrical component (17) to be measured and a horizontal rotation angle ω of the rotationally symmetrical component (17) to be measured, wherein the measuring instrument (4) is fixed to the xy translation stage (2); The first theodolite (5) and the second theodolite (6) form a triangle with the position line of the placement platform (3), and are used to measure the rotationally symmetrical component (17) to be measured placed on the placement platform (3) from two horizontal directions.

2. The positioning device based on a rotationally symmetrical component according to claim 1, characterized in that: The invention also includes a support platform (7) and a lifting rod (8), both of which correspond to the first theodolite (5) and the second theodolite (6) one by one. The support platform (7) is used to support the first theodolite (5) or the second theodolite (6), and the lifting rod (8) is used to adjust the height of the first theodolite (5) or the second theodolite (6). The two ends of the lifting rod (8) are respectively connected to the first theodolite (5) and the support platform (7), and the two ends of the other lifting rod (8) are respectively connected to the second theodolite (6) and the other support platform (7).

3. The positioning device based on a rotationally symmetrical component according to claim 1, characterized in that: It also includes a reference platform (9) fixed to the xy translation platform (2) and used for installing the placement platform (3), so that the placement platform (3) can rotate horizontally relative to the reference platform (9) and can translate along the x direction and the y direction.

4. A positioning method based on a rotationally symmetrical component, characterized in that: Using the positioning device based on a rotationally symmetrical component according to any one of claims 1 to 3, the positioning method includes: Adjusting the heights and angles of the first theodolite (5) and the second theodolite (6) so that the center mark (15) of the xy translation stage (2) is located on the vertical reference line (12) of the field of view of the first theodolite (5) and the second theodolite (6), and then adjusting the elevation angles of the first theodolite (5) and the second theodolite (6) to zero; Marking a point to be measured (18) on the surface of the rotationally symmetrical component (17) to be measured, placing the rotationally symmetrical component (17) to be measured on the placement table (3), and ensuring that the symmetry axis (19) of the rotationally symmetrical component (17) to be measured is perpendicular to the surface of the placement table (3); The placement table (3) is rotated horizontally for at least one revolution, and L and ω are recorded simultaneously, and the position (x0, y0) of the symmetry axis (19) of the rotationally symmetrical component (17) to be measured in the coordinate system formed by the x-direction and the y-direction is determined based on the relationship between L and ω; According to the position (x0, y0), the position of the placement table (3) is adjusted along the x-direction and the y-direction so that the symmetry axis (19) of the rotationally symmetrical component (17) to be measured is returned to zero; Adjusting the height of the workbench (1) so that the horizontal reference line (13) of the field of view of the first theodolite (5) or the second theodolite (6) coincides with the point to be measured (18); The position of the xy translation stage (2) is adjusted along the x-direction and the y-direction so that the vertical reference line (12) of the field of view of the first theodolite (5) or the second theodolite (6) coincides with the point to be measured (18).

5. The positioning method based on rotationally symmetrical components according to claim 4, characterized in that: After adjusting the position of the placement table (3) along the x-direction and the y-direction and before adjusting the height of the workbench (1), the method further comprises the following steps: The placement platform (3) is rotated horizontally for at least one revolution, L and ω are recorded simultaneously, and the position (x0′, y0′) of the symmetry axis (19) of the rotationally symmetrical component (17) to be measured is determined by using a curve fitting method; According to the position (x0′, y0′), the position of the placement platform (3) is adjusted along the x-direction and the y-direction to return the symmetry axis (19) of the rotationally symmetrical component (17) to be measured to zero.

6. The positioning method based on rotationally symmetrical components according to claim 5, characterized in that: The curve fitting method is to establish a trigonometric function relationship between L and ω.

7. The positioning method based on rotationally symmetrical components according to claim 4, characterized in that: When determining the position (x0, y0), based on L and ω, find the farthest distance L max and the corresponding rotation angle ω max , the measured closest distance L min , the rotation angle ω corresponding to the measured closest distance min , and establish trigonometric function relationships to solve them.

8. The positioning method based on rotationally symmetrical components according to claim 4, characterized in that: After the horizontal reference line (13) coincides with the point to be measured (18) and the vertical reference line (12) coincides with the point to be measured (18), the placement table (3) is rotated horizontally for at least one circle, and L and ω are recorded at the same time; if L remains unchanged, the process ends; if L changes with ω, the process repeats the steps after placing the rotationally symmetrical component to be measured (17) on the placement table (3) and before adjusting the height of the workbench (1).

9. The positioning method based on rotationally symmetrical components according to claim 4, characterized in that: When the rotationally symmetrical component (17) to be measured is placed on the placement platform (3), it is ensured that the extension line of the distance measurement path of the measuring instrument (4) passes through the rotation axis of the placement platform (3).

10. The positioning method based on rotationally symmetrical components according to claim 4, characterized in that: Also includes: When the heights and angles of the first theodolite (5) and the second theodolite (6) are adjusted, the neutron beam height markers (16) are both located at the central focus (14) of the fields of view of the first theodolite (5) and the second theodolite (6).

Images