Oxygen bomb micro-deformation quantity detection method and system based on machine vision

Abstract

The invention relates to an oxygen bomb micro-deformation quantity detection method based on machine vision, and the method comprises the steps: building at least one pair of online projection image measuring instruments at the two sides of an oxygen bomb in a horizontal plane, obtaining the orthographic projection of the outline of the oxygen bomb, driving the oxygen bomb to intermittently rotate in situ around the axis at a set angle, and obtaining the micro-deformation quantity of the oxygen bomb. In the intermittent process, thrust is applied to the oxygen bomb connecting ring in the radial direction or the axial direction to reach a set value, and the displacement amount of a plurality of radial loosening measuring points and a plurality of axial loosening measuring points on the projection of the oxygen bomb connecting ring before and after the thrust is applied is obtained on the basis of an online projection image measuring instrument; calculating an average based on the plurality of displacements, and outputting the radial loosening degree and the axial loosening degree of the oxygen bomb thread; the oxygen bomb is subjected to pressure relief after a hydrostatic test, the diameters of the 1 / 2 height of the bomb body before pressurization and after pressure relief are obtained based on an online projection image measuring instrument, and the diameter deformation quantity is obtained by subtracting the diameters.

Description

Technical Field

[0001] This application belongs to the technical field of oxygen bomb detection, and particularly relates to a method and system for detecting the micro-deformation of an oxygen bomb based on machine vision. Background Art

[0002] An oxygen bomb calorimeter is an instrument used to measure the calorific value of substances that can burn completely in oxygen. As the combustion chamber of the oxygen bomb calorimeter, the oxygen bomb needs to withstand the high-temperature and high-pressure environment generated during the combustion process of the internal sample. The oxygen bomb usually consists of a cover body, a bomb body, and a connecting ring used to fix the cover body by threaded connection with the bomb body. To ensure that the oxygen bomb can safely complete the measurement of the sample calorific value, it is necessary to regularly or before the experiment detect the safety performance of the oxygen bomb. Among them, the deformation detection result on the surface of the oxygen bomb can best reflect the performance and state of the oxygen bomb, especially the radial looseness, axial looseness of the thread between the oxygen bomb and the connecting ring, and the diameter change at the 1 / 2 height of the bomb body after the hydrostatic test.

[0003] In the prior art, the radial looseness of the oxygen bomb thread is measured through the test device in MT / T737-2007 "Calorimeter Oxygen Bomb Safety Performance Inspection Specification". This experimental device includes a measurement platform; an oxygen bomb fixing frame arranged on the measurement platform for fixing the oxygen bomb; an experimental ring for moving the threaded connecting ring of the oxygen bomb; and a micrometer for measuring the deformation amount on the surface of the oxygen bomb. Although this device can meet the basic measurement of the oxygen bomb, when measuring the deformation amounts on the surface of each oxygen bomb, not only does the operator need to operate the micrometer at different positions of the oxygen bomb for reading, but also the operator needs to manually move the experimental ring to detect the thread looseness. The operation steps are not only cumbersome and complex, but also prone to deviation in the thread looseness rebound or looseness direction due to different force application methods and magnitudes by the operator, resulting in different values that may be measured by different operators. Summary of the Invention

[0004] Based on the above needs in the background art, this application provides a method for detecting the micro-deformation of an oxygen bomb based on machine vision, which can solve the problems in the prior art that when measuring the deformation amounts on the surface of each oxygen bomb, not only does the operator need to operate the micrometer at different positions of the oxygen bomb for reading, but also the operator needs to manually move the experimental ring to detect the thread looseness. The operation steps are not only cumbersome and complex, but also prone to deviation in the thread looseness rebound or looseness direction due to different force application methods and magnitudes by the operator, resulting in different values that may be measured by different operators.

[0005] To achieve the above object, the technical solution of this application is:

[0006] A method for detecting the radial looseness of an oxygen bomb thread includes the following steps:

[0007] S1. Build at least one set of online projection image measuring instruments in a horizontal plane, and obtain an oxygen bomb micro-shape variable detection calibration interface based on the online projection image measuring instrument; fix the oxygen bomb body between the online projection image measuring instruments so that the orthographic projection of the oxygen bomb's outer contour is located within the oxygen bomb micro-shape variable detection calibration interface;

[0008] S2. Drive the oxygen bomb to rotate around its axis at an angle w, pause m times during the rotation process, and obtain n points on the orthographic projection of the oxygen bomb's connecting ring contour during each pause as radial looseness measurement points or axial looseness measurement points; apply a thrust to F or F' along the radial or axial direction of the oxygen bomb to the connecting ring of the oxygen bomb during the pause, and obtain the displacements D1 to D1 of the radial looseness measurement point or the axial looseness measurement point within the oxygen bomb micro-deformation detection calibration interface based on the online projection image measuring instrument. n , where n and m are both ≥ 1; based on the formula Calculate the radial looseness or axial looseness of the oxygen bomb thread, where m represents the number of pauses in the rotation process, n represents the number of first test points, i = 1, 2, ..., n, and d represents the radial looseness or axial looseness of the oxygen bomb thread, ensuring that when the thrust is equal to F or F', the radial deformation or axial deformation of the oxygen bomb connecting ring is 0;

[0009] S3. Reset the oxygen bomb and perform a 20 MPa hydraulic pressure test on the oxygen bomb. After depressurization, obtain the diameter M2 of the oxygen bomb at 1 / 2 the height of the bomb body using an online projection image measuring instrument. Calculate the diameter deformation at 1 / 2 the height of the oxygen bomb body using the formula m = M2 - M1, where m represents the diameter deformation at 1 / 2 the height of the oxygen bomb body, and M1 represents the diameter of the oxygen bomb at 1 / 2 the height of the bomb body before the hydraulic pressure test.

[0010] Preferably, in step S2, the displacements D1 to D2 of the radial looseness measurement point or the axial looseness measurement point in the oxygen bomb micro-deformation variable detection calibration interface are obtained. n Specifically, the method includes: in each intermittent time, taking at least one point on the orthographic projection of the oxygen bomb body contour as the second measuring point; when the thrust is equal to 0, outputting the radial distance L between any radial looseness measuring point or axial looseness measuring point and any second measuring point based on the online projection image measuring instrument; when the thrust is equal to F or F′, calculating the radial displacement of the radial looseness measuring point or the axial looseness measuring point and the second measuring point based on the formula D=|LH|.

[0011] Preferably, the rotation angle of the oxygen bomb is 180°≤w≤360°.

[0012] The present application provides an oxygen bomb micro-deformation detection system based on machine vision, including a measurement platform; a driving component arranged on the top of the measurement platform, and the output end of the driving component is used to drive the oxygen bomb to rotate; a fixing component arranged on the top of the measurement platform for fixing the bomb body of the oxygen bomb; a radial pushing component arranged on the top of the measurement platform and on one side of the driving component for radially pushing the connecting ring of the oxygen bomb; an axial pushing component arranged on the top of the measurement platform and on one side of the driving component for axially pushing the connecting ring of the oxygen bomb; a pressure generating component for providing liquid pressure to the oxygen bomb; a pressurized connection component arranged on the top of the measurement platform for hermetically connecting the pressure generating component with the oxygen bomb; and at least one set of on-line projection image measuring instruments arranged on the top of the measurement platform and symmetrically distributed on both sides of the driving component for forming a projection plane of the oxygen bomb.

[0013] Preferably, the driving component includes a stepping motor arranged on the top of the measurement platform, and the driving shaft of the stepping motor is used to drive the oxygen bomb to rotate.

[0014] Preferably, the fixing component includes at least a pair of brackets, and any pair of the brackets is arranged on the top of the measurement platform and symmetrically distributed on both sides of the driving component; a first push rod is arranged at the top of the bracket, and a bomb body fixing piece is arranged at the output end of the first push rod, and the first push rod is used to synchronously drive the bomb body fixing piece to move radially.

[0015] Preferably, the radial pushing component includes a first lifting frame arranged on the top of the measurement platform and on one side of the driving component, a second push rod is arranged at the output end of the first lifting frame, and a connecting ring pushing piece is arranged at the output end of the second push rod. The first lifting frame is used to drive the second push rod to move axially, and the second push rod is used to drive the connecting ring pushing piece to move radially.

[0016] Preferably, the axial pushing component includes at least a pair of second lifting frames, and any pair of the second lifting frames is arranged on the top of the measurement platform and symmetrically distributed on both sides of the driving component. A third push rod is arranged at the output end of the second lifting frame, a fourth push rod is arranged at the output end of the third push rod, and a dial rod is arranged at the output end of the fourth push rod. The second lifting frame is used to drive the third push rod to move axially, the third push rod is used to drive the fourth push rod to move radially, and the fourth push rod is used to drive the dial rod to move axially.

[0017] Preferably, the pressure connection assembly includes a gantry, a lead screw, and an oxygen bomb pressure head disposed on the top of the measurement platform. The gantries are symmetrically distributed on both sides of the drive assembly. The lead screw is in threaded transmission cooperation with the gantry along the axial direction. The oxygen bomb pressure head is disposed at the lower end of the lead screw. A pressure joint is disposed at the lower end of the oxygen bomb pressure head, and a pressure interface is disposed on the side surface of the oxygen bomb pressure head. The pressure joint is communicated with the pressure interface.

[0018] Preferably, the pressure generating assembly includes a water tank, a pre-pressure pump, and a water supply pipe. The pre-pressure pump is communicated with the water tank. One end of the water supply pipe is connected to the pre-pressure pump, and the other end is connected to the pressure interface. A pressure cut-off valve and a return water pipe are disposed at intervals on the water supply pipe. Both ends of the return water pipe are respectively communicated with the water supply pipe and the water tank. A pressure reducing valve is disposed on the return water pipe.

[0019] By adopting the above technical solutions, compared with the prior art, the present application has at least the following beneficial effects:

[0020] By applying the online projection image measuring instrument to measure the radial loosening value, axial loosening value of the oxygen bomb thread, and the diameter at the 1 / 2 height of the bomb body of the oxygen bomb after pressure relief, and utilizing the characteristics that the online projection image measuring instrument can accurately and directly measure the tolerances and clearances of precision structures, combined with the existing methods for oxygen bomb measurement, the accurate and efficient detection of the radial loosening degree, axial loosening degree of the oxygen bomb thread, and the diameter at the 1 / 2 height of the bomb body of the oxygen bomb after pressure relief is realized; during the whole detection process, there is no need to use inefficient and operation technique-dependent equipment such as external micrometers and dial indicators in the prior art for measurement and reading, which simplifies the detection process. Description of the Drawings

[0021] Figure 1 It is the front projection contour schematic diagram A showing the radial loosening of the oxygen bomb in the embodiment.

[0022] Figure 2 It is the front projection contour schematic diagram B showing the axial loosening of the oxygen bomb in the embodiment.

[0023] Figure 3 It is the front projection contour schematic diagram C showing the diameter deformation of the oxygen bomb in the embodiment.

[0024] Figure 4 It is the assembly schematic diagram of the oxygen bomb micro-deformation amount detection system in the embodiment.

[0025] Figure 5 It is the sectional view D-D of the oxygen bomb micro-deformation amount detection system in the embodiment.

[0026] Figure 6 It is the partial enlarged sectional view E (taken fromFigure 5 )。

[0027] Figure 7 It is an axonometric structure schematic diagram of the oxygen bomb micro-deformation detection system in the embodiment.

[0028] Figure 8 It is a partial enlarged view F of the oxygen bomb micro-deformation detection system in the embodiment (taken from Figure 7 )

[0029] In the figure: measurement platform 10, drive assembly 20, stepper motor 21, oxygen bomb support seat 22, anti-slip part 221, lifting platform 222, drive motor 223, connection base 224, fixing assembly 30, bracket 31, first push rod 32, bomb body fixing part 321, first pressure sensor 322, radial pushing assembly 40, first lifting frame 41, second push rod 42, connecting ring pushing part 421, second pressure sensor 422, axial pushing assembly 50, second lifting frame 51, third push rod 52, fourth push rod 53, lever 531, third pressure sensor 532, pressurization connection assembly 60, gantry 61, lead screw 62, crank 621, oxygen bomb pressure head 63, pressure joint 64, pressure interface 641, pressure generating assembly 70, water tank 71, pre-pressure pump 72, water supply pipe 73, pressurization stop valve 731, return water pipe 74, pressure reducing valve 741, on-line projection image measuring instrument 80, oxygen bomb 90, bomb body 91, connecting ring 92. Detailed implementation manners

[0030] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The following will further describe the technical solutions of the present application in conjunction with the drawings of the embodiments of the present application. The present application is not limited to the following specific implementation manners.

[0031] It should be understood that the same or similar reference numerals in the drawings of the embodiments correspond to the same or similar components. In the description of the present application, it should be understood that if there are terms such as "upper", "lower", "inner", "outer", "left", "right", "front", "rear", "top", "bottom", etc. indicating directions or position relationships, they are based on the directions or position relationships shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the structures or components referred to must have specific orientations, be constructed and operated in specific orientations. Therefore, the terms describing the position relationships in the drawings are only for illustrative purposes and cannot be understood as limitations on this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific situations.

[0032] The following will further describe the present application in detail in conjunction with the attached Figure 1 to the attached Figure 8 and specific embodiments.

[0033] The present application discloses a method for detecting the micro-deformation amount of an oxygen bomb based on machine vision. The method includes the following steps:

[0034] Step 1:

[0035] Set up at least one set of on-line projection image measuring instruments 80 in a horizontal plane, and obtain an oxygen bomb micro-deformation amount detection calibration interface (hereinafter referred to as "calibration interface") based on the on-line projection image measuring instruments 80; fix the bomb body 91 between the on-line projection image measuring instruments 80 so that the orthographic projection of the outer contour of the oxygen bomb 90 is located within the calibration interface;

[0036] The specific process of implementing this step is as follows: Place the oxygen bomb 90 to be detected in a horizontal plane, and set up at least one set of on-line projection image measuring instruments 80 in this horizontal plane. Based on the telecentric optical projection system of the on-line projection image measuring instruments 80, form an oxygen bomb micro-deformation amount detection calibration interface between the lenses of any pair of on-line projection image measuring instruments 80 through the principle of parallel light projection. This calibration interface is a plane perpendicular to the horizontal plane where the viewing angle range that can be irradiated by the parallel light emitted from the lenses of the on-line projection image measuring instruments 80 is located. The on-line projection image measuring instruments 80 are used to compare and measure the moving distance of the projection of the object appearing in this calibration interface or the distance between the points on the object projection contour; based on the relative positions of the on-line projection image measuring instruments 80 and the oxygen bomb 90, make the parallel light emitted by the on-line projection image measuring instruments 80 perpendicularly hit the surface of the oxygen bomb 90 along the axis of the oxygen bomb 90, and project the orthographic projection of part or all of the contour of the outer shape of the oxygen bomb 90 into the above-mentioned calibration interface, such as the images in Figure 1 Appendix Figure 2 or Appendix Figure 3 (The images in the above appendices are all simulated interfaces and do not represent the real images of the on-line projection image measuring instruments 80), so as to obtain the micro-deformation amount of the oxygen bomb 90 in this calibration interface through the following operations;

[0037] Step 2: On the premise that the oxygen bomb 90 is controlled to remain in its original position (i.e., the positional relationship between the oxygen bomb 90 and at least one set of on-line projection image measuring instruments 80 remains unchanged in the horizontal plane), the oxygen bomb 90 is driven by the device to rotate around its axis from 0° to w°. During the process of the oxygen bomb 90 rotating to w°, it pauses m times (i.e., the oxygen bomb 90 stops rotating m times). During the pause time, n points are selected on the orthographic projection of the contour of the connecting ring 92 as radial looseness measurement points or axial looseness measurement points (it should be noted that when obtaining the axial looseness measurement points, the oxygen bomb 90 is reset and rotated around its axis from 0° to w° again to separate the measurement process of the radial looseness of the thread and the measurement process of the axial looseness of the thread). During the pause time, a thrust is applied to the connecting ring 92 along the radial direction of the oxygen bomb 90 to F or a thrust is applied to the connecting ring 92 along the axial direction of the oxygen bomb 90 to F'. This thrust may cause the connecting ring 92 part to have a parallel displacement or a vertical displacement relative to the bomb body 91 part. After the thrust reaches F or F', based on the on-line projection image measuring instrument 80, the displacement amounts D1 to D of the above-mentioned radial looseness measurement points or axial looseness points within the calibration interface are obtained n (D1 represents the displacement amount of the first radial looseness measurement point or the first axial looseness measurement point, and so on. D n represents the displacement amount of the nth radial looseness measurement point or axial looseness measurement point), where both n and m are ≥ 1; based on the formula Calculate the radial looseness of the oxygen bomb thread or the axial looseness of the oxygen bomb thread, where m represents the number of pauses during the rotation process, n represents the number of the first test points, i = 1, 2,... n, d represents the radial looseness of the oxygen bomb thread and the axial looseness of the thread, and ensure that when the thrust is equal to F or F', the axial deformation amount or the radial deformation amount of the connecting ring 92 is 0;

[0038] Specifically, this step is divided into two steps to measure the radial looseness and the axial looseness of the oxygen bomb 90 thread respectively, and the order is not in sequence. First, control the oxygen bomb 90 to rotate from the initial position to w°. During the rotation process, it pauses m times at a fixed pause angle. During each pause time, at least one radial looseness measurement point is selected on the projection contour of the connecting ring 92. Preferably, as shown in the appendix Figure 1 Among them, two points, upper and lower, are selected on the left side of the projection contour of the connecting ring 92 as radial looseness measurement points; a radial thrust is applied to the connecting ring 92 to F. Based on the measurement function of the on-line projection image measuring instrument 80 for the distance between points on the projection, the displacement distance of each radial looseness measurement point from the position in the state where the thrust is 0 to the position in the state where the thrust reaches F is measured, that is, the displacement amounts of all radial looseness measurement points within the calibration interface are obtained; then based on the formula Find the average displacement of all radial loosening measurement points, and this average value is the radial loosening degree of the thread of the oxygen bomb 90 to be measured; secondly, re-control the oxygen bomb 90 to rotate from the initial position to w°, and during the rotation process, it is intermittent m times at a fixed intermittent angle. During each intermittent time period, at least one axial loosening measurement point is selected on the projected contour of the connecting ring 92. Preferably, see the appendix Figure 2 In the figure, select two upper and lower points on the left side of the projected contour of the connecting ring 92 as the axial loosening measurement points, apply an axial thrust to the connecting ring 92 until F′, and based on the measurement function of the on-line projection image measuring instrument 80 for the point spacing on the projection, measure the displacement distance of each axial loosening measurement point from the position in the state where the thrust is 0 to the position in the state where the thrust reaches F′, that is, obtain the displacement of all axial loosening measurement points within the calibration interface; then based on the formula Find the average displacement of all axial loosening measurement points, and this average value is the axial loosening degree of the thread of the oxygen bomb 90 to be measured.

[0039] In the above process, w represents the angle value at which the oxygen bomb 90 finally stops rotating in a complete process of measuring the radial loosening degree of the thread; m represents the number of intermittent times during the process of the oxygen bomb 90 rotating to w°. Specifically, m can be set based on w°. If the total rotation angle value of the oxygen bomb 90 is 180°, in order to ensure that the positions of the selected first measurement points are relatively average, the oxygen bomb 90 can be controlled to be intermittent once every 45° of rotation, that is, the whole process is intermittent 4 times; based on the provisions of MT / T 737-2007 "Calorimeter Oxygen Bomb Safety Performance Inspection Specification", the axial loosening degree of the thread obtained in the above steps is not greater than 0.27 mm is qualified, as shown in the appendix Figure 2 In the figure, the axial loosening degree of the thread is 0.43 mm, which is judged as unqualified; the loosening degree of the thread is not greater than 0.45 mm is qualified, as shown in the appendix Figure 1 In the figure, the radial loosening degree of the thread is 0.355 mm, which is judged as qualified.

[0040] In addition, in this step, to ensure that the displacement of the first measurement point obtained in the above embodiment is only due to the radial loosening or axial loosening of the connecting ring 92 relative to the bomb body 91, the maximum limit value of the thrust F or F′ applied to the connecting ring 92 during the measurement process should not be sufficient to cause radial deformation or axial deformation of the connecting ring 92 itself, so as to prevent the radial deformation or axial deformation of the connecting ring 92 itself caused by excessive thrust from affecting the displacement of the connecting ring 92 during thread radial loosening or thread axial loosening.

[0041] Step 3: Reset the oxygen bomb 90 to its initial position. Conduct a 20 MPa water pressure test on the oxygen bomb 90 in accordance with the provisions of MT / T 737-2007 "Specification for Inspection of the Safety Performance of Oxygen Bombs in Calorimeters". Combine with the measurement function of the distance between points on the projection of the oxygen bomb 90 by the online projection image measuring instrument 80 after pressure relief, measure the diameter at the 1 / 2 height of the bomb body of the oxygen bomb 90 to obtain M2. Calculate the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb 90 based on the formula m = M2 - M1, where m represents the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb 90, M1 represents the diameter at the 1 / 2 height of the bomb body of the oxygen bomb 90 before the water pressure test, and M1 is measured by the online projection image measuring instrument 80 before the water pressure test.

[0042] Specifically, adjust the height of the oxygen bomb 90 on the horizontal plane so that the orthographic projection contour of the bomb body 91 is within the calibration interface. Based on the online projection image measuring instrument 80, output the diameters at the 1 / 2 height of the bomb body of the oxygen bomb 90 before and after pressure relief respectively. By calculating the difference between the two, obtain the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb 90 before and after pressure relief. According to the provisions of MT / T 737-2007 "Specification for Inspection of the Safety Performance of Oxygen Bombs in Calorimeters", if the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb 90 after pressure relief is less than 0.13 mm, it is qualified. As shown in the appendix Figure 3 In the figure, the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb 90 after pressure relief reaches 0.1 mm, which is determined to be qualified.

[0043] The above method for detecting the micro-deformation of the oxygen bomb based on machine vision has at least the following beneficial effects:

[0044] By applying the online projection image measuring instrument 80 to measure the radial loosening value, axial loosening value of the oxygen bomb thread and the diameter at the 1 / 2 height of the bomb body of the oxygen bomb 9 after pressure relief, and utilizing the characteristics that the online projection image measuring instrument 80 can accurately and directly measure the tolerances and clearances of precision structures, combined with the existing methods for measuring the oxygen bomb 90, realize the accurate and efficient detection of the radial loosening degree, axial loosening degree of the oxygen bomb thread and the diameter at the 1 / 2 height of the bomb body of the oxygen bomb 90 after pressure relief; during the whole detection process, there is no need to use inefficient and operation technique-dependent equipment such as outside micrometers and dial indicators in the prior art for measurement and reading, which simplifies the detection process.

[0045] In addition, the present application also provides some more specific implementation manners to improve the above method for detecting the micro-deformation of the oxygen bomb based on machine vision.

[0046] To simplify the calculation process of detection and give full play to the efficiency and accuracy of the online projection image measuring instrument 80 in detecting the radial looseness and axial looseness of the oxygen bomb threads: during each intermittent time in the process of the above-mentioned oxygen bomb 90 rotating to an angle of w°, at least one point on the orthographic projection of the contour of the bomb body 91 is used as the second measurement point. Preferably, see the appendix Figure 1 In the appendix, when measuring the radial looseness value of the thread, two upper and lower points are selected on the left side of the projection contour of the bomb body 91 as the second measurement points. First, when the thrust applied to the connecting ring 92 is 0 (i.e., before the thrust is applied), based on the online projection image measuring instrument 80, the radial distance L between any one of the above-mentioned radial looseness measurement points and any one of the second measurement points is output; when the thrust applied to the connecting ring 92 reaches the limit value F, based on the online projection image measuring instrument 80, the stable distance H between the same radial looseness measurement point and the same second measurement point along the radial direction is output. The displacement of the radial looseness measurement point along the radial direction within the calibration interface is calculated by the formula D = |L - H|, and the average value of each group of obtained displacements is calculated to obtain the radial looseness of the thread.

[0047] See the appendix Figure 2 In the appendix, when measuring the axial looseness value of the thread, two upper and lower points are selected on the left side of the projection contour of the bomb body 91 as the second measurement points. First, when the thrust applied to the connecting ring 92 is 0 (i.e., before the thrust is applied), based on the online projection image measuring instrument 80, the axial distance L between any one of the above-mentioned axial looseness measurement points and any one of the second measurement points is output; when the thrust applied to the connecting ring 92 reaches the limit value F', based on the online projection image measuring instrument 80, the stable distance H between the same axial looseness measurement point and the same second measurement point along the axial direction is output. That is, L represents the vertical distance between a certain point on the contour of the connecting ring 92 and a certain point on the contour of the bomb body 91 before the force is applied. The displacement of the radial looseness measurement point along the axial direction within the calibration interface is calculated by the formula D = |L - H|.

[0048] Specifically, preferably, the Keyence - TM - X5000 series online projection image measuring instrument 80 is used. Without changing the basic algorithm of its measurement, by measuring the radial distance between the same pair of measurement points on the oxygen bomb 90 in two states before applying force and when the force reaches F through this online projection image measuring instrument 80, the due measurement level of this type of online projection image measuring instrument 80 can be exerted; and since the bomb body 91 remains stationary during the process before applying force and when applying force, by selecting the second measurement point on the bomb body 91 as the reference point, the position change of the radial looseness measurement point or the axial looseness measurement point can be more clearly reflected.

[0049] Further, to ensure that the displacement of the obtained radial looseness measurement point or axial looseness measurement point can fully represent the numerical level of the radial looseness or axial looseness of the connecting ring 92, the rotation angle of the above-mentioned oxygen bomb 90 during a single measurement of the radial looseness or axial looseness of the thread is 180° ≤ w ≤ 360°.

[0050] In one embodiment, it is known that the maximum measurement range of the Keyence - TM - X5000 series of online projection image measuring instruments 80 preferably used in this application does not exceed 120 mm. To ensure that a set of online projection image measuring instruments 80 within this measurement range can implement the above step two, the maximum outer diameter of the oxygen bomb 90 to be measured should not exceed 120 mm, so as to ensure that the projection range of the online projection image measuring instrument 80 can cover the maximum width of the orthographic projection contour of the oxygen bomb 90. Within this measurement range, as long as the in-situ rotation angle of the oxygen bomb 90 is controlled to be not less than 180°, the front view and rear view of the oxygen bomb 90 can be projected onto the calibration interface, so as to ensure that the selected radial looseness measurement point or axial looseness measurement point is any point within the circumferential range of the connecting ring 92;

[0051] In another embodiment, to ensure that the online projection image measuring instrument 80 carried can detect the radial looseness or axial looseness of the thread of the oxygen bomb 90 with a maximum outer diameter exceeding 120 mm (for example, the outer diameter of the oxygen bomb 90 in GB9706.1 - 2020 is 123 mm), a scheme of parallelly building two sets of online image projection measuring instruments in the horizontal plane is adopted, so that the sum of the projection ranges of the two sets of online image projection measuring instruments can cover the maximum width of the orthographic projection contour of the oxygen bomb 90. In this embodiment, by controlling the in-situ rotation angle of the oxygen bomb 90 to reach 180°, the front view and rear view of the oxygen bomb 90 can also be projected onto the calibration interface, so as to ensure that the selected radial looseness measurement point or axial looseness measurement point is any point within the circumferential range of the connecting ring 92;

[0052] In another solution different from the above two embodiments, if only one set of online projection image measuring instruments 80 can be built due to cost or other conditions, and the measurement range of this online projection image measuring instrument 80 is not sufficient to cover the maximum width of the orthographic projection contour of the oxygen bomb 90, the oxygen bomb 90 can be offset - that is, only one side of the orthographic projection contour of the oxygen bomb 90 (this "one side" refers to the side including the connecting ring 92 and the bomb body 91) is placed within the calibration range of the online projection image measuring instrument 80, and the in-situ rotation angle of the oxygen bomb 90 is controlled to reach 360°, so as to ensure that the selected radial looseness measurement point or axial looseness measurement point is any point within the circumferential range of the connecting ring 92.

[0053] Further, to ensure that the displacement of the radial looseness measurement point or the axial looseness measurement point obtained in the above embodiments is solely due to the radial or axial looseness of the connecting ring 92 relative to the elastic body 91, and to prevent the deformation of the connecting ring 92 itself caused by excessive thrust from affecting the radial looseness value or the axial looseness value of the thread of the connecting ring 92, it is necessary to ensure that the value of the applied thrust F or F' is not sufficient to cause deformation of the connecting ring 92.

[0054] In MT / T 737-2007 "Calorimeter Oxygen Bomb Safety Performance Inspection Specification", in the standards for measuring the radial looseness and axial looseness of the threads of the oxygen bomb 90, the experimenter needs to manually push the test ring to push the connecting ring 92, and the relevant standards do not specify how much the thrust for pushing the connecting ring 92 is. It only indicates that the purpose of applying this thrust is not to cause forced displacement of the connecting ring 92, and the magnitude of the thrust should be such that it does not damage the thread integrity and can complete the measurement of radial or axial looseness. Given the relatively vague definition of this standard, during the implementation of the above steps, the thrust on the connecting ring 92 should be controlled at least within the range that does not damage the thread integrity of the oxygen bomb, which is equivalent to ensuring that the thrust applied to the oxygen bomb 90 in this application does not cause radial or axial deformation of the connecting ring 92 or the connecting ring 92.

[0055] Specifically, the method for determining the value of the thrust F or F' is as follows: The numerical limit of this thrust can be obtained through the following method: The operator conducts tests on the radial looseness or axial looseness of the threads of oxygen bombs 90 of various models in accordance with the provisions of MT / T 737-2007 "Calorimeter Oxygen Bomb Safety Performance Inspection Specification". During the test, the operator manually pushes the test ring and selects multiple test points to measure the radial or axial looseness of the threads. On the premise of ensuring that the test results are consistent with the actual situation, by setting a thrust sensor or a pressure sensor on the test ring, such as a thin-film pressure sensor - when an external force acts on this sensor, the elastic film (such as a silicon diaphragm, a metal or a polymer film) deforms, resulting in a change in the resistance value of the strain resistors (such as diffused silicon resistors or carbon pastes) attached to the film. This change is converted into a voltage signal output through a Wheatstone bridge circuit, thereby reflecting the magnitude of the pressure), and based on the pressure sensor, multiple groups of thrust values are recorded. Through data statistics, the limit value of the thrust applied to the oxygen bomb 90 during the test is obtained, such as the average value or the maximum value of multiple groups of thrust values. This limit value can be used as a reference in this application.

[0056] Further, the above step two also includes a process of rechecking the displacement D of the above radial looseness measurement point and axial looseness measurement point within the calibration interface. The specific steps are as follows:

[0057] During the implementation of the above step 2, within the same intermittent time of selecting the above radial looseness measurement point / axial looseness measurement point or the second measurement point, with the rotation axis of the oxygen bomb 90 as the symmetry axis, the point symmetric to any radial looseness measurement point or axial looseness measurement point is used as the third measurement point. See Appendix Figure 1 and Appendix Figure 2 In, a point symmetric to one of the above radial looseness measurement points or axial looseness measurement points is selected on the right side of the projection contour of the connecting ring 92 as the third measurement point, and a point symmetric to one of the above second measurement points is selected on the same side as the second measurement point for review. When the above thrust F or F' is equal to 0, through the same method as the above step 2, based on the online projection image measuring instrument 80, the radial distance L' between the third measurement point and the second measurement point is measured; when the thrust is equal to F or F', based on the online projection image measuring instrument 80, the radial distance H' between the third measurement point and the same second measurement point is output. Based on the formula D' = |L' - H'|, the displacement of the third measurement point along the radial or axial direction within the calibration interface is calculated, and D is reviewed based on D'. If D' is equal to D, the radial looseness value or axial looseness value of the thread is calculated based on the above formula; if D' is not equal to D, it proves that the connecting ring 92 may have deformed under the action of the thrust or the critical value of the thrust is too large, resulting in forced displacement of the connecting ring 92 or the connecting ring 92, causing different displacement amounts of the points on both sides of the orthographic projection contour of the connecting ring 92. In this case, the critical value F of the thrust is adjusted until D' is equal to D, and then the measurement is carried out. Specifically, when implementing this review step, it can be implemented together with the above step 2, so that each D value obtained during each intermittent process can have a corresponding D' review to ensure that the applied thrust meets the requirements.

[0058] In addition to the above oxygen bomb micro-deformation detection method, the present application also discloses an oxygen bomb micro-deformation detection system based on machine vision, which can be applied to the above method to detect the radial looseness of the oxygen bomb thread, the axial looseness of the oxygen bomb thread, and the diameter deformation amount at the 1 / 2 height of the bomb body.

[0059] The device includes a measurement platform 10 for providing a horizontal plane for building an online projection image measuring instrument 80; a driving component 20 disposed on the top of the measurement platform 10, and the output end of the driving component 20 is used to drive the oxygen bomb 90 to rotate; a fixing component 30 disposed on the top of the measurement platform 10 for fixing the bomb body 91; a radial pushing component 40 disposed on the top of the measurement platform 10 and on one side of the driving component 20 for radially pushing the connecting ring 92; an axial pushing component 50 disposed on the top of the measurement platform 10 and on one side of the driving component 20 for axially pushing the connecting ring 92; a pressure generating component 70 for providing liquid pressure to the oxygen bomb 90 to perform a 20 MPa water pressure test on the oxygen bomb 90; a pressurizing connection component 60 disposed on the top of the measurement platform 10 for sealingly connecting the pressure generating component 70 and the oxygen bomb 90; and at least one set of online projection image measuring instruments 80 disposed on the top of the measurement platform 10 and symmetrically distributed on both sides of the driving component 20 for forming a projection plane of the oxygen bomb 90.

[0060] In a specific embodiment, the above-mentioned measurement platform 10 is a box body with a hollow bottom, and the driving component 20 includes a stepping motor 21, which is disposed on the inner top surface of the measurement platform 10, and the driving shaft can drive the oxygen bomb 90 to rotate.

[0061] In order to enable the oxygen bomb 90 to rotate smoothly and in place, an oxygen bomb support seat 22 is coaxially arranged on the driving shaft of the stepping motor 21 and can carry the rotation of the oxygen bomb 90. Specifically, the oxygen bomb support seat 22 can increase the friction between its top surface and the oxygen bomb 90 by providing an anti-slip portion 221 on its top, ensuring that the oxygen bomb 90 can rotate with the driving shaft of the stepping motor 21 and preventing the oxygen bomb 90 from slipping and shifting. The anti-slip portion 221 can be a rubber pad attached to the top surface of the oxygen bomb support seat 22, or structures such as grooves and flanges that fit the bottom surface of the oxygen bomb 90 can be provided on the top surface of the oxygen bomb support seat 22 to fix the oxygen bomb 90.

[0062] Further, to drive the oxygen bomb 90 to move up and down in a lifting manner to finely adjust the projection position of the oxygen bomb 90 in the height direction, the above oxygen bomb support base 22 includes a connection base 224 disposed on the drive shaft of the stepping motor 21, a drive motor 223 disposed on the top of the connection base 224, and a lifting table 222 disposed on the drive shaft of the drive motor 223. Among them, the connection base 224 is cylindrical, its bottom surface is coaxially fixed with the drive shaft of the stepping motor 21, its side surface is rotatably connected to the top surface of the measurement platform 10 through a bearing, and its inner surface is slidably matched with the cylindrical lifting table 222. The drive motor 223 is a servo motor, and a threaded structure is machined at one end of its drive shaft or a lead screw 62 is connected. A threaded hole is provided at the center of the bottom of the lifting table 222 and is in threaded transmission cooperation with the drive shaft of the drive motor 223. The servo motor can drive the lifting table 222 to rotate forward or backward, so that the lifting table 222 rotates up or down under the action of the threaded structure. When the servo motor does not output power, the frictional force between the lifting table 222 and the connection base 224 causes the lifting table 222 to be locked in the vertical direction, so that during the process of the stepping motor 21 driving the connection base 224 to rotate relative to the measurement platform 10, the lifting table 222 only rotates synchronously with the connection base 224 and does not perform lifting movement.

[0063] Further, the above fixing assembly 30 includes at least a pair of brackets 31. Any pair of brackets 31 are symmetrically distributed on both sides of the above drive assembly 20 above the top surface of the measurement platform 10. In a preferred embodiment, the axis of symmetry is the extension line of the drive shaft of the above stepping motor 21; first push rods 32 are respectively provided at the tops of the brackets 31, and a bullet fixing member 321 is provided at the output end of the first push rod 32. Specifically, the first push rod 32 is a servo electric push rod, and the bullet fixing member 321 is a push plate or a claw with an arc-shaped surface. The arc-shaped side thereof is used to fit and hold the bullet 91 tightly. The other side of the bullet fixing member 321 is connected to the output shaft of the servo electric push rod, and the first push rod 32 can push the bullet fixing member 321 to move synchronously in the radial direction.

[0064] Further, to ensure that the fixing assembly 30 can adjust the corresponding thrust according to the specifications of the oxygen bomb 90 to be measured to meet the fixation of oxygen bombs 90 with different diameters, a first pressure sensor 322 is embedded on the side surface of the bullet fixing member 321 that can contact the bullet 91. On the premise that the thrust value of the first push rod 32 is set, the first push rod 32 can push or stop pushing based on the pressure signal fed back by the first pressure sensor 322, so that a pair of bullet fixing members 321 can hold the bullet 91 tightly with a set thrust, thereby avoiding loosening of the bullet 91 caused by insufficient thrust or damage to the first push rod 32 or the oxygen bomb 90 caused by excessive thrust.

[0065] In another embodiment, there are the following differences from the above embodiment:

[0066] Under the condition that other structures are the same, the fixing component 30 is different. In this embodiment, the fixing component 30 includes an industrial suction cup with adjustable suction force. The industrial suction cup is coaxially fixed to the upper end of the drive shaft of the stepping motor 21 and the suction surface faces upward. The stepping motor 21 can drive the industrial suction cup to rotate around the axis, and can drive the oxygen bomb 90 adsorbed on the top of the industrial suction cup to rotate. When the oxygen bomb 90 needs to be taken or replaced, adjust the suction force of the industrial suction cup so that it can firmly adsorb the bottom of the bomb body 91 or release the oxygen bomb 90.

[0067] In a preferred embodiment, the above-mentioned radial pushing component 40 includes a first lifting frame 41 arranged on the top of the measuring platform 10 and on one side of the driving component 20. The output end of the first lifting frame 41 is provided with a second push rod 42, and the output end of the second push rod 42 is provided with a connecting ring pushing member 421. Specifically, the above-mentioned connecting ring pushing member 421 is an arc-shaped push plate whose one surface can fit the side surface of the connecting ring 92. The first lifting frame 41 includes a servo electric push rod capable of outputting in the vertical direction, and its output end is provided with another servo electric push rod capable of outputting in the radial direction (i.e., the second push rod 42). The output end of the latter is connected to the above-mentioned connecting ring pushing member 421. The first lifting frame 41 adjusts the position of the connecting ring pushing member 421 in the vertical direction so that it can be within the height range where the connecting ring 92 is located (to make the thrust applied to the connecting ring 92 relatively uniform, the connecting ring pushing member 421 should contact the middle part of the side surface of the connecting ring 92). The second push rod 42 on the first lifting frame 41 can drive the connecting ring pushing member 421 in the radial direction to apply a set thrust F to the connecting ring 92.

[0068] Furthermore, to ensure that the radial pushing component 40 can accurately apply a set radial thrust to the connecting ring 92, a second pressure sensor 422 is arranged on one side surface of the connecting ring pushing member 421 that can contact the connecting ring 92. On the premise that the thrust value of the second push rod 42 is set, the second push rod 42 can execute pushing or stop pushing based on the pressure signal fed back by the second pressure sensor 422, so that the connecting ring pushing member 421 can apply the set thrust to the connecting ring 92, thereby avoiding inaccurate measurement of the radial looseness of the thread due to insufficient thrust resulting in no thread loosening between the connecting ring 92 and the bomb body 91, or excessive thrust damaging the thread structure or causing deformation of the connecting ring 92.

[0069] Furthermore, to improve the efficiency of the above oxygen bomb micro-deformation detection system when measuring the radial looseness of the oxygen bomb, a pair of the above radial pushing assemblies 40 may be provided and symmetrically distributed on both sides of the driving assembly 20, so that the connecting ring 92 can be subjected to a leftward or rightward thrust by any one of the radial pushing assemblies 40. By alternately using different radial pushing assemblies 40, the oxygen bomb 90 can be rotated by a smaller angle and the displacement amounts of the same number of radial looseness measurement points along the radial direction within the oxygen bomb micro-deformation detection calibration interface can be obtained, thereby improving the measurement efficiency.

[0070] In one embodiment, the above axial pushing assembly 50 includes at least a pair of second lifting frames 51 provided on the top of the measurement platform 10. Any pair of second lifting frames 51 are symmetrically distributed on both sides of the driving assembly 20. The output end of the second lifting frame 51 is provided with a third push rod 52. The output end of the third push rod 52 is provided with a fourth push rod 53. The output end of the fourth push rod 53 is provided with a lever 531. Specifically, in a preferred embodiment, the second lifting frame 51 includes a servo electric push rod capable of outputting in the vertical direction, and its output end is provided with another servo electric push rod capable of outputting in the radial direction (i.e., the third push rod 52). A pair of second lifting frames 51 can synchronously push the third push rod 52 upward in the vertical direction with the same thrust, so that the lever 531 can be within the height range where the bottom of the connecting ring 92 is located. The third push rod 52 can drive the lever 531 radially closer to the bottom of the connecting ring 92, so that the lever 531 approaches the bottom of the connecting ring 92. The fourth push rod 53 is a micro servo electric push rod with adjustable thrust (having a smaller pushing stroke and adjustable thrust function compared to the second lifting frame 51 and the third push rod 52). The fourth push rod 53 can drive the lever 531 to move upward along the axial direction with a small stroke, and apply an upward thrust F' to the connecting ring 92.

[0071] Furthermore, to ensure that the axial pushing assembly 50 can accurately apply a set axial thrust to the connecting ring 92, the top surface of the lever 531 is a plane parallel to the bottom surface of the connecting ring 92, and a third pressure sensor 532 is provided on the part of the top surface of the lever 531 that can fully contact the bottom surface of the connecting ring 92. On the premise that the thrust value of the fourth push rod 53 is set, the fourth push rod 53 can execute pushing or stop pushing based on the pressure signal fed back by the third pressure sensor 532, so that the lever 531 can apply the set thrust to the connecting ring 92, thereby avoiding inaccurate measurement of the thread axial looseness due to insufficient thrust resulting in no thread loosening between the connecting ring 92 and the bomb body 91, or excessive thrust damaging the thread structure or causing deformation of the connecting ring 92.

[0072] In order to enable the above-mentioned projectile fixing member 321, connecting ring pushing member 421, and lever 531 to apply thrust evenly to the oxygen bomb 90 and avoid stress concentration, the above-mentioned first pressure sensor 322, second pressure sensor 422, and third pressure sensor 532 are all preferably a thin-film pressure sensor. The pressure detection ends in the form of thin films are respectively embedded or attached to the side surfaces of the projectile fixing member 321, connecting ring pushing member 421, and lever 531 that are used to contact the oxygen bomb 90. The pressure detection ends in the form of thin films can not only avoid the problem of thrust concentration but also help improve the pressure feedback accuracy.

[0073] Based on the above-mentioned implementation manner, to ensure that the online projection image measuring instrument 80 can clearly detect the phenomenon of radial loosening of the thread between the connecting ring 92 and the projectile 91, it is necessary to ensure that the projection plane of the above-mentioned oxygen bomb 90 is parallel to the direction in which the radial pushing assembly 40 pushes the connecting ring 92. When the oxygen bomb 90 is applied with thrust, the connecting ring 92 and the projectile 91 undergo a loosening displacement in a direction parallel to the projection plane, so that the online projection image measuring instrument 80 can output the radial loosening value.

[0074] Furthermore, in order to enable the above-mentioned oxygen bomb micro-deformation detection system to perform a hydrostatic test on the oxygen bomb 90 and measure the diameter deformation at the 1 / 2 height of the projectile 91, the above-mentioned pressurizing connection assembly 60 includes a gantry 61, a lead screw 62, and an oxygen bomb pressure head 63 provided on the top of the platform. Specifically, the two side columns of the gantry 61 in the shape of a door frame are symmetrically distributed on both sides of the driving assembly 20 (i.e., symmetrically distributed on both sides of the rotation axis of the oxygen bomb 90). The lead screw 62 axially penetrates through the axis of the gantry 61 and is in threaded transmission cooperation with the gantry 61. A crank 621 is provided at the upper end of the lead screw 62, and an oxygen bomb pressure head 63 is provided at the lower end. A pressure joint 64 is provided at the lower end of the oxygen bomb pressure head 63. The pressure joint 64 can be connected to the interface on the oxygen bomb cover under the action of downward pressure. A pressure interface 641 is provided on the side surface of the oxygen bomb pressure head 63. The pressure interface 641 is internally connected to the pressure joint 64 to form a water flow path. When in use, the operator rotates the crank 621 to move the lead screw 62 downward, driving the oxygen bomb pressure head 63 to move downward and connecting the pressure joint 64 to the interface on the oxygen bomb cover. Under the downward pressure of the oxygen bomb pressure head 63, the pressure joint 64 is hermetically connected to the interface on the oxygen bomb cover.

[0075] Further, the above-mentioned pressure generating assembly 70 includes a water tank 71, a pre-pressure pump 72, and a water supply pipe 73. Among them, the water tank 71 is built into the bottom of the above-mentioned measurement platform 10 for easy movement. In this embodiment, water is used as the pressurizing medium and stored in the water tank 71. The pre-pressure pump 72 is a lever-type pre-pressure pump, including a pump head and a lever mechanism arranged on the top of the measurement platform 10. One end of the pump head is connected through a water supply pipe 73 provided with a pressure regulating stop valve 731, and the other end of the water supply pipe 73 is detachably connected to the pressure interface 641. A one-way valve is arranged between the pressure regulating stop valve 731 and the water tank 71. A return water pipe 74 is arranged on the water supply pipe 73 between the pressure regulating stop valve 731 and the pressure interface 641. One end of the return water pipe 74 is connected to the water tank 71, and a pressure reducing valve 741 is arranged on the return water pipe 74. The handles of the pressure reducing valve 741 and the pressure regulating stop valve 731 are both arranged on the side of the measurement platform 10 for easy operation. After the pressure regulating stop valve 731 is opened and the pressure reducing valve 741 is closed, the pump head is continuously in a negative pressure or positive pressure state through the lever mechanism, sucking out the water in the water tank 71 and injecting it into the oxygen bomb 90 through the pressure regulating stop valve 731. The safety pressure of the pre-pressure pump 72 is 0 - 40 MPa, and the required pressure for the hydraulic test of the oxygen bomb 90 is 20 MPa ± 0.2 MPa, which can meet the technical requirements for pressurization required by the elastic deformation and permanent deformation of the oxygen bomb 90. The water supply pipe 73 is a high-pressure hose provided with a quick-release sealing joint, which can withstand a pressure of not less than 40 MPa; after the pressure regulating stop valve 731 is closed, the pressurization in the oxygen bomb 90 can be stopped; after the pressure reducing valve 741 is opened, due to the pressure in the oxygen bomb 90 being higher than the pressure in the water tank 71, the water in the oxygen bomb 90 flows back through the water supply pipe 73 and the return water pipe 74 to relieve the pressure of the oxygen bomb 90.

[0076] When using the above-mentioned oxygen bomb micro-deformation detection system:

[0077] Ensure that the drive assembly 20, the fixing assembly 30, the radial pushing assembly 40, the axial pushing assembly 50, and the pressure generating assembly 70 are in the initial position or state;

[0078] The online projection image measuring instrument 80 is in the detection standby state, and the oxygen bomb 90 to be detected is placed at the axis of the anti-slip part 221;

[0079] After driving the bomb fixing part 321 with a set thrust through the first push rod 32 to fix the bomb body 91 part, start the second push rod 42 to apply a set thrust to the radial direction of the connecting ring 92 to F;

[0080] Output a set of oxygen bomb thread radial loosening values through the online projection image measuring instrument 80;

[0081] Reverse the operation of the second push rod 42 to cancel the thrust, reverse the operation of the first push rod 32 to relax the projectile 91, start the stepping motor 21 to drive the oxygen bomb 90 to rotate in place by a set rotation angle. The set angle is preferably 45°. After reaching the set rotation angle, repeat the above steps until the rotation angle of the oxygen bomb 90 relative to the initial rotation position is not less than 180°. Output multiple sets of radial looseness values of the oxygen bomb thread. By calculating the average of multiple sets of radial looseness values of the oxygen bomb thread, obtain the measured value of the radial looseness of the thread of the oxygen bomb 90;

[0082] Reset the oxygen bomb 90. After driving the projectile fixing part 321 with the first push rod 32 to fix the projectile 91 part with a set thrust, start the second lifting frame 51 and the third push rod 52 to move the lever 531 to a position close to the bottom of the connecting ring 92. Then start the fourth push rod 53 to apply a set thrust F' to the axial direction of the connecting ring 92;

[0083] Output a set of axial looseness values of the oxygen bomb thread through the online projection image measuring instrument 80;

[0084] Reverse the operation of the fourth push rod 53 to cancel the thrust, reverse the operation of the first push rod 32 to relax the projectile 91, start the stepping motor 21 to drive the oxygen bomb 90 to rotate in place by a set rotation angle. The set angle is preferably 45°. After reaching the set rotation angle, repeat the above steps until the rotation angle of the oxygen bomb 90 relative to the initial rotation position is not less than 180°. Output multiple sets of axial looseness values of the oxygen bomb thread. By calculating the average of multiple sets of axial looseness values of the oxygen bomb thread, obtain the measured value of the axial looseness of the thread of the oxygen bomb 90;

[0085] Reset the oxygen bomb 90 and output the initial diameter at the 1 / 2 height of the projectile through the online projection image measuring instrument 80;

[0086] Operate the crank 621 to make the pressure joint 64 be hermetically connected to the oxygen bomb 90, connect the water supply pipe 73 to the pressure interface 641, and pressurize the oxygen bomb 90 to 20 MPa through the pre-pressure pump 72 for a hydrostatic test;

[0087] Open the pressure reducing valve 741 to relieve pressure. After complete pressure relief, output the restored diameter at the 1 / 2 height of the projectile through the online projection image measuring instrument 80. Calculate the diameter deformation amount at the 1 / 2 height of the projectile of the oxygen bomb 90 by subtracting the restored diameter from the initial diameter.

[0088] Obviously, the above embodiments of the present application are only examples clearly illustrating the present application, rather than limiting the implementation manners of the present application. For those of ordinary skill in the art, other different forms of changes or variations can be made on the basis of the above description. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A method for detecting the micro-deformation of an oxygen bomb based on machine vision, characterized in that, It includes the following steps: S1. Set up at least one set of on-line projection image measuring instruments in the horizontal plane, and obtain the calibration interface for detecting the micro-deformation of the oxygen bomb based on the on-line projection image measuring instruments; fix the bomb body of the oxygen bomb between the on-line projection image measuring instruments, so that the orthographic projection of the outer contour of the oxygen bomb is located within the calibration interface for detecting the micro-deformation of the oxygen bomb. S2. Drive the oxygen bomb to rotate around the axis with an angular rotation of w, intermittently m times during the rotation process, and obtain n points on the orthographic projection of the connecting ring contour of the oxygen bomb as radial looseness measurement points or axial looseness measurement points within each intermittent time; Apply a thrust to the connecting ring of the oxygen bomb along the radial or axial direction of the oxygen bomb to F or F' respectively during the intermittent time, and respectively measure the displacement amounts D1 to D of the radial looseness measurement points or axial looseness measurement points within the micro-deformation detection calibration interface of the oxygen bomb based on the online projection image measuring instrument n , where both n and m are ≥ 1; Based on the formula Calculate the radial looseness of the oxygen bomb thread or the axial looseness of the oxygen bomb thread. Among them, m represents the number of intermittent times during the rotation process, n represents the number of the first test points, i = 1, 2,... n, d represents the radial looseness of the oxygen bomb thread and the axial looseness of the thread, and ensure that when the thrust is equal to F or F', the radial deformation amount or axial deformation amount of the connecting ring of the oxygen bomb is 0; S3. Reset the oxygen bomb, conduct a 20 MPa water pressure test on the oxygen bomb. After pressure relief, obtain the diameter M2 at the 1 / 2 height of the bomb body of the oxygen bomb based on the on-line projection graphic measuring instrument, and calculate the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb according to the formula m = M2 - M1, where m represents the diameter deformation at the 1 / 2 height of the bomb body of the oxygen bomb, and M1 represents the diameter at the 1 / 2 height of the bomb body of the oxygen bomb before the water pressure test.

2. The oxygen bomb micro-deformation amount detection method according to claim 1, characterized in that In the step S2, obtain the displacement D1 to D of the radial loosening measurement point or the axial loosening measurement point within the oxygen bomb micro-deformation detection and calibration interface. n Specifically, it includes: within each intermittent time, use at least one point on the orthographic projection of the oxygen bomb's body contour as the second measurement point. When the thrust is equal to 0, measure the radial distance L between any radial loosening measurement point or axial loosening measurement point and any of the second measurement points based on the online projection image measuring instrument. When the thrust is equal to F or F', measure the radial distance H between the radial loosening measurement point or the axial loosening measurement point and the second measurement point based on the online projection image measuring instrument. Calculate the displacement of the radial loosening measurement point along the radial direction within the oxygen bomb micro-deformation detection and calibration interface or the displacement of the axial loosening measurement point along the axial direction within the oxygen bomb micro-deformation detection and calibration interface based on the formula D = |L - H|.

3. The oxygen bomb micro-deformation amount detection method according to claim 2, characterized in that, The rotation angle w of the oxygen bomb satisfies 180° ≤ w ≤ 360°.

4. A machine vision-based oxygen bomb micro-deformation detection system is applied to the oxygen bomb micro-deformation detection method described in any one of claims 1 to 3, and is characterized in that, It includes a measurement platform; a driving component, arranged at the top of the measurement platform, and the output end of the driving component is used to drive the oxygen bomb to rotate; a fixing component, arranged at the top of the measurement platform, used to fix the bomb body of the oxygen bomb; a radial pushing component, arranged at the top of the measurement platform and on one side of the driving component, used to push the connecting ring of the oxygen bomb radially; an axial pushing component, arranged at the top of the measurement platform and on one side of the driving component, used to push the connecting ring of the oxygen bomb axially; a pressure generating component, used to provide liquid pressure to the oxygen bomb; a pressurizing connection component, arranged at the top of the measurement platform, used to seal-connect the pressure generating component and the oxygen bomb; and at least one set of on-line projection image measuring instruments, arranged at the top of the measurement platform and symmetrically distributed on both sides of the driving component, used to form the projection plane of the oxygen bomb.

5. The oxygen bomb micro-deformation detection system according to claim 4, characterized in that, The driving component includes a stepping motor, and the stepping motor is arranged at the top of the measurement platform, and the driving shaft of the stepping motor is used to drive the oxygen bomb to rotate.

6. The oxygen bomb micro-deformation detection system according to claim 4, wherein The fixing component includes at least a pair of brackets, and any pair of the brackets is arranged at the top of the measurement platform and symmetrically distributed on both sides of the driving component; a first push rod is arranged at the top of the bracket, and a bomb body fixing piece is arranged at the output end of the first push rod, and the first push rod is used to synchronously drive the bomb body fixing piece to move radially.

7. The oxygen bomb micro-deformation detection system according to claim 4, characterized in that, The radial pushing component includes a first lifting frame, and the first lifting frame is arranged at the top of the measurement platform and on one side of the driving component, and a second push rod is arranged at the output end of the first lifting frame, and a connecting ring pushing piece is arranged at the output end of the second push rod. The first lifting frame is used to drive the second push rod to move axially, and the second push rod is used to drive the connecting ring pushing piece to move radially.

8. The oxygen bomb micro-deformation detection system according to claim 4, wherein The axial pushing assembly includes at least a pair of second lifting frames. Any pair of the second lifting frames is arranged on the top of the measuring platform and symmetrically distributed on both sides of the driving assembly. The output end of the second lifting frame is provided with a third push rod. The output end of the third push rod is provided with a fourth push rod. The output end of the fourth push rod is provided with a dial rod. The second lifting frame is used to drive the third push rod to move axially. The third push rod is used to drive the fourth push rod to move radially. The fourth push rod is used to drive the dial rod to move axially.

9. The oxygen bomb micro-deformation detection system according to claim 4, wherein The pressurizing connection assembly includes a gantry, a lead screw and an oxygen bomb pressure head arranged on the top of the measuring platform. The gantries are symmetrically distributed on both sides of the driving assembly. The lead screw is in threaded transmission cooperation with the gantry along the axial direction. The oxygen bomb pressure head is arranged at the lower end of the lead screw. A pressure joint is arranged at the lower end of the oxygen bomb pressure head. A pressure interface is arranged on the side surface of the oxygen bomb pressure head. The pressure joint is communicated with the pressure interface.

10. The oxygen bomb micro-deformation detection system according to claim 9, characterized in that, The pressure generating assembly includes a water tank, a pre-pressure pump and a water supply pipe. The pre-pressure pump is communicated with the water tank. One end of the water supply pipe is connected to the pre-pressure pump, and the other end is connected to the pressure interface. A pressure cut-off valve and a return pipe are arranged at intervals on the water supply pipe. Both ends of the return pipe are respectively communicated with the water supply pipe and the water tank. A pressure reducing valve is arranged on the return pipe.

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