A Portable Bend Pipe Measuring Device and Method

Abstract

The present invention discloses a portable pipe bending measurement device and method for measuring a pipeline. The portable pipe bending measurement device includes a binocular vision module, a pipe end adapter, and a plurality of pipe axis adapters. The pipe end adapter is used for fixedly connecting to the end of a pipeline to be measured, and the plurality of pipe axis adapters are respectively used for clamping on the pipe axis between the two ends of the pipeline to be measured. The pipe end adapter includes an end face positioning portion, an axial positioning portion, and a first fixing unit, and a plurality of marking points are respectively arranged on the end face positioning portion and the axial positioning portion; the pipe axis adapter includes a second fixing unit and two panels, and a plurality of marking points are respectively arranged on the two panels. The portable pipe bending measurement device and method proposed by the present invention have no special restrictions on the geometric dimensions of the pipe measurement and the measurement platform, and have good universality.

Description

Technical Field

[0001] The present invention relates to the technical field of elbow measurement, and in particular to a portable elbow measurement device and method. Background Art

[0002] Elbows are important components in fields such as aviation, automotive, and marine, mainly responsible for the transmission of oil, liquid, gas, etc. The three-dimensional geometric dimension accuracy thereof not only affects the reliability of the overall system, but may also cause safety problems during use. In addition, during the use of the pipeline system, it is inevitable that single pipeline damage repair occurs, and the possible pipeline size deformation will also affect the geometric dimensions of the pipe fittings to be replaced. Therefore, the measurement of the pipelines that have not been disassembled and assembled in the system is also an important issue. Therefore, during the production and manufacturing process and before installation, it is necessary to measure or detect the geometric dimensions of the pipelines to determine whether they meet the geometric dimension requirements.

[0003] Currently, the inspection of the external geometric dimension accuracy of pipes mainly includes fixture inspection methods, measurement and inspection methods based on scanning, and measurement and inspection methods based on stereo vision.

[0004] Currently, the most widely used method in industry is still the fixture inspection method. According to the design dimensions and corresponding tolerances of the pipe fittings, corresponding pipe fitting fixtures are designed. After the produced pipe fittings are placed in the fixture, it is observed whether they meet the dimension requirements. Although the fixture inspection method is fast and intuitive, secondary errors may be caused during the process of disassembling and assembling into the fixture. In addition, each type of pipe fitting corresponds to a fixture, and a large number of fixtures need to be manufactured to meet the measurement requirements of the pipe fittings.

[0005] The measurement and inspection methods based on scanning include contact three-coordinate measurement, non-contact laser or white light scanning methods, and the model of the pipe fitting is obtained by reconstructing the point cloud on the surface of the pipe fitting. For the scanning-based method, the pipe fitting needs to be fixed at a certain measurement position, and the position needs to be kept unchanged during the measurement to prevent the reconstructed shape from being incorrect due to position changes during the reconstruction process. After the reconstructed point cloud model undergoes post-processing such as point cloud denoising, fusion, and model fitting, the pipe model data is obtained. The efficiency is low, and the quality of the point cloud will seriously affect the accuracy of the obtained model.

[0006] The measurement and inspection methods based on stereo vision mainly include binocular and multi-view vision methods, and the corresponding model of the pipe fitting is obtained by the method of reconstructing the pipe axis by acquiring the pipeline image. By comparing the reconstructed model with the design model, it is checked whether its geometric dimensions meet the design tolerance requirements. For the vision-based method, the measurement efficiency is high, but in the existing systems, the measurement of the pipe size is limited by the design dimensions of the measurement system, and the pipe to be measured needs to be placed on the corresponding developed measurement platform, and the geometric dimensions of the pipeline components cannot be measured.

[0007] In summary, the main disadvantages of the current pipeline reconstruction detection methods are as follows: either the measurement efficiency is low, or there are limitations in the measurement size and measurement platform.

[0008] The disclosure of the above background technical content is only used to assist in understanding the concept and technical solution of the present invention, and it does not necessarily belong to the prior art of this patent application. Without clear evidence indicating that the above content was publicly available on the filing date of this patent application, the above background technology should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0009] To solve the above technical problems, the present invention proposes a portable bent pipe measurement device and method, which has no special restrictions on the geometric dimensions of the pipe measurement and the measurement platform, and has good universality.

[0010] To achieve the above object, the present invention adopts the following technical solutions:

[0011] An embodiment of the present invention discloses a portable bent pipe measurement device for measuring a pipeline to be measured, including a binocular vision module, a pipe end adapter, and a plurality of pipe axis adapters. The pipe end adapter is used for fixedly connecting to the end of the pipeline to be measured, and the plurality of pipe axis adapters are respectively used for clamping on the pipe axis between the two ends of the pipeline to be measured, wherein:

[0012] The pipe end adapter includes an end face positioning portion, an axial positioning portion, and a first fixing unit. The end face positioning portion and the axial positioning portion are perpendicularly connected to the first fixing unit. The first fixing unit is used for fixedly connecting to the pipeline to be measured. The end face positioning portion is perpendicular to the axis of the pipeline to be measured, and the axial positioning portion passes through the axis of the pipeline to be measured. A plurality of marking points are respectively provided on the end face positioning portion and the axial positioning portion;

[0013] The pipe axis adapter includes a second fixing unit and two panels. A plurality of marking points are respectively provided on the two panels, and the two panels are connected at a predetermined angle to enable the marking points on the two panels to be simultaneously recognized by the binocular vision module. The second fixing unit is used for wrapping the pipeline to be measured between the two panels.

[0014] Preferably, the first fixing unit includes a chuck, a jaw driving mechanism, and a plurality of positioning jaws. The jaw driving mechanism is arranged inside the chuck, and the plurality of positioning jaws are connected to the jaw driving mechanism to drive the plurality of positioning jaws to clamp on the inner wall of the pipeline to be measured or clamp on the outer wall of the pipeline to be measured through the jaw driving mechanism; a cylindrical pin is provided at the bottom of the axial positioning portion, and the cylindrical pin is coaxial with the axis of the pipeline to be measured and is positioned and connected to the chuck.

[0015] Preferably, the multiple pipe shaft adapters clamped between the two ends of the pipeline to be measured meet the following requirements: at least one of the pipe shaft adapters is clamped on each straight line segment of the pipeline to be measured, and at least two adjacent pipe shaft adapters are included in the same field of view area when the binocular vision module takes pictures.

[0016] An embodiment of the present invention discloses a bent pipe measurement method, which uses the above-mentioned portable bent pipe measurement device to measure the pipeline to be measured, including the following steps:

[0017] S1: Calibrate the binocular vision module;

[0018] S2: Equip the pipe end adapters at the two ends of the pipeline to be measured respectively, and calibrate the pipe end adapters;

[0019] S3: Equip multiple pipe shaft adapters on the pipe shaft between the two ends of the pipeline to be measured according to preset requirements;

[0020] S4: Move the binocular vision module along the extension direction of the pipeline to be measured, so as to use the binocular vision module to collect images with the pipe shaft adapter or images with both the pipe shaft adapter and the pipe end adapter at different positions, where there is a common field of view area between the two images collected at every two adjacent positions, and at least one pipe shaft adapter is included in the common field of view area;

[0021] S5: Identify the identification points of the pipe shaft adapter or the images with both the pipe shaft adapter and the pipe end adapter collected in the binocular vision module, and match and reconstruct the identification points;

[0022] S6: Align the identification points of the pipe shaft adapter and the identification points of the pipe end adapter reconstructed by the binocular vision module at different positions in step S5, so as to unify all the identification points of the pipe shaft adapter and all the identification points of the pipe end adapter into the same coordinate system, and then align the identification points of the pipe end adapter unified into the same coordinate system with the calibrated pipe end adapter;

[0023] S7: Reconstruct the overall structure model of the pipeline to be measured according to all the identification points of the pipe shaft adapter and all the aligned identification points of the pipe end adapter in the same coordinate system.

[0024] Preferably, the step of calibrating the pipe end adapter in step S2 specifically includes:

[0025] S21: Rotate the axial positioning part of the pipe end adapter along the axis of the pipeline to be measured, and collect at least 5 images including the pipe end adapter, where the axial positioning part rotates to different angles when each image is collected;

[0026] S22: Reconstruct the spatial coordinates of the identification points on the pipe end adapter;

[0027] S23: Determine whether the number of identification points reconstructed in step S22 meets the requirements. If not, return to step S21; if so, execute step S24;

[0028] S24: Fit the identification points and establish geometric relationships.

[0029] Preferably, step S24 specifically includes: establishing the positional relationships of the identification points on the pipe end adapter when the axial positioning parts are at different angles respectively, fitting the axis (L0) of the pipeline to be measured through the respective positions of the identification points on the axial positioning part, fitting the plane (P0) of the end face positioning part through the identification points on the end face positioning part, establishing the coordinate system of the pipe end adapter according to the axis (L0) and the plane (P0), and obtaining the coordinates of the center point of the pipe end face of the pipeline to be measured in the coordinate system of the pipe end adapter.

[0030] Preferably, in step S3, a plurality of pipe axis adapters are equipped on the pipe axis between the two ends of the pipeline to be measured according to preset requirements, where the preset requirements include: at least one pipe axis adapter is equipped on each straight line segment of the pipeline to be measured, and at least two adjacent pipe axis adapters are included in the same field of view area when the binocular vision module takes pictures.

[0031] Preferably, step S6 specifically includes:

[0032] S61: Perform point matching on multiple groups of pipe axis adapter identification points, or multiple groups of pipe axis adapter identification points and pipe end adapter identification points in two images with a common field of view area using the identification points on the pipe axis adapters in the common field of view area;

[0033] S62: Obtain the rotation matrix R and translation matrix T for aligning the coordinate system (C2) in one image to the coordinate system (C1) in the other image according to the following formula:

[0034]

[0035] In the formula, are the same identification points in the coordinate system (C1) and the coordinate system (C2) respectively, and n is the number of identification points on the pipe axis adapters in the common field of view area;

[0036] S63: Align all the identification points in the coordinate system (C2) to the coordinate system (C1) through the rotation matrix R and translation matrix T obtained in step S62;

[0037] S64: Repeat steps S61 to S63 to sequentially match and align the identified points of the tube axis adapter and the identified points of the tube end adapter rebuilt at each position, so as to unify all the identified points of the tube axis adapter and all the identified points of the tube end adapter into the same coordinate system, and then align the identified points of the tube end adapter unified into the same coordinate system with the calibrated tube end adapter.

[0038] Preferably, step S7 specifically includes:

[0039] S71: Calculate each set of tube axis lines based on the relative geometric relationship between each tube axis adapter and the tube axis line of the pipeline to be measured.

[0040] S72: Calculate the intersection points of two axis lines through adjacent sets of tube axis lines, and sequentially complete the reconstruction of all axis intersection points.

[0041] S73: Calculate the coordinates of the center point of the tube end face of the pipeline to be measured according to all the identified points of the tube end adapter after alignment.

[0042] An embodiment of the present invention discloses a computer-readable storage medium storing computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the steps of the above-mentioned bent tube measurement method.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows: The portable bent tube measurement device and method proposed by the present invention can simply and quickly complete tube axis reconstruction. Among them, the tube axis lines can be matched and aligned by adapter coding alignment. The measurement length of the tube is not limited. The measurement position can be for measuring the size of the pipeline to be measured in the pipeline system, or for measuring the pipeline to be measured in offline production or repair of the system. The pipeline to be measured can be a single-piece pipeline measurement or a pipeline component measurement, and the application range is wide. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic structural diagram of the portable bent tube measurement device according to the preferred embodiment of the present invention;

[0045] Figure 2 is Figure 1 the installation schematic diagram of the tube end adapter in

[0046] Figure 3 is Figure 1 the installation schematic diagram of the tube axis adapter in

[0047] Figure 4 is a schematic flow diagram of the bent tube measurement method according to the preferred embodiment of the present invention;

[0048] Figure 5It is a schematic diagram of the calibration panel;

[0049] Figure 6 It is a schematic diagram of the placement of the calibration panel;

[0050] Figure 7 It is a schematic diagram of the calibration process of the pipe end adapter;

[0051] Figure 8 It is a schematic diagram of the coordinate system of the pipe end adapter;

[0052] Figure 9 It is a schematic diagram of the coordinate system alignment of the pipe shaft adapter;

[0053] Figure 10 It is a schematic diagram of the structure of the pipeline to be measured obtained by reconstruction. Specific implementation manners

[0054] The following makes a detailed description of the implementation manners of the present invention. It should be emphasized that the following description is merely exemplary and not intended to limit the scope of the present invention and its applications.

[0055] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, the connection can be for a fixing function or for a circuit / signal connection function.

[0056] It should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention.

[0057] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0058] In a preferred embodiment of the present invention, in view of the problems in the prior art that the measurement size and position of the pipe are restricted and the measurement component cannot measure quickly, a portable pipe measurement device and method based on binocular stereo vision are provided, which can simply, quickly and effectively complete the pipe measurement.

[0059] As Figure 1 shown, an embodiment of the present invention provides a portable pipe measurement device based on binocular stereo vision for measuring a pipeline 10 to be measured, including a binocular vision module 20, two pipe end adapters 30 and a plurality of pipe axis adapters 40. In this embodiment, the two pipe end adapters 30 are respectively labeled as pipe end adapters 301 and 302, and the plurality of pipe axis adapters 40 are respectively labeled as pipe axis adapters 401, 402, 403, 404, and 405. Only one binocular vision module 20 needs to be used in this device. The two binocular vision modules 20 shown in the figure are different positions where the binocular vision module 20 moves during the image acquisition process. In the embodiment of the present invention, images of different adapters are obtained by the binocular vision module 20 acquiring images at different positions, so as to further process and obtain the measurement data of the pipeline 10 to be measured.

[0060] Among them, the binocular vision module 20 includes two high-resolution industrial cameras, an adapter lens, a transmission line and a fixed support frame. The two industrial cameras are fixed on the fixed support frame. During the process of measuring the pipeline 10 to be measured, the relative positions of the two industrial cameras in the binocular vision module 20 remain unchanged. At the same time, according to the measurement requirements of different pipelines, the relative positions of the two industrial cameras can be adjusted to meet different measurement field of view requirements.

[0061] As Figure 2 shown, it is a structural schematic diagram of the pipe end adapter 30. The pipe end adapter 30 includes an end face positioning portion 31, an axial positioning portion 32 and a fixing unit. The fixing unit adopts a three-jaw chuck type self-positioning structure, including a chuck 33 and a plurality of positioning jaws 34. A jaw driving mechanism (not shown in the figure) is provided in the chuck 33 to drive the plurality of positioning jaws, and the inner wall or outer wall of the pipe can be clamped according to requirements. In this embodiment, the inner wall clamping structure of the pipeline 10 to be measured is adopted; a cylindrical pin 321 is provided below the axial positioning portion 32 to be positioned in the chuck 33 through the cylindrical pin 321, and the cylindrical pin 321 is coaxially arranged with the axis of the pipeline 10 to be measured. A plurality of marking points 50 are respectively provided on the end face positioning portion 31 and the axis positioning portion 32.

[0062] As Figure 3As shown in the figure, it is a schematic structural diagram of the pipe axis adapter 40. The pipe axis adapter 40 includes two panels 41, 42 and an elastic panel 43. The two panels 41, 42 are connected by a shaft at a predetermined angle. The elastic panel 43 wraps the pipeline 10 to be measured between the two panels 41, 42. One end of the elastic panel 43 is fixedly connected to the panel 41, and the other end is connected to the panel 42 by a hooking method; identification points 50 are respectively provided on the panels 41, 42, and the included angle between the panels 41, 42 needs to ensure that the identification points on the two panels 41, 42 can be simultaneously recognized by the cameras in the binocular vision module 20, so that the pipe axis position of the pipeline 10 to be measured can be directly calculated through the identification points on the two panels 41, 42. In this embodiment, the thicknesses of the two panels 41, 42 are equal and both are d.

[0063] Among them, when configuring the quantity and clamping positions of the pipe axis adapters 40, the following conditions need to be met: at least one pipe axis adapter 40 should be clamped on each straight line segment of the pipeline 10 to be measured. At the same time, when using the binocular stereo vision module 20 to take pictures, at least two adjacent pipe axis adapters 40 should be included in the same field of view area for subsequent unifying the pipe axis coordinate system. When installing the pipe axis adapter 40, the two surfaces with identification points 50 in each pipe axis adapter 40 should be simultaneously facing the direction of the binocular vision module 20 to ensure that the identification points on the two planes can be simultaneously reconstructed.

[0064] As Figure 4 shown, an embodiment of the present invention provides a bent pipe measurement method based on binocular stereo vision, which specifically includes the following steps:

[0065] S1: Binocular vision module calibration

[0066] By collecting calibration panel images, the internal parameters and external parameters of the cameras in the binocular vision module are calibrated. The calibration panel includes coded identification points and non-coded identification points.

[0067] In this embodiment, two industrial cameras in the binocular vision module are calibrated by using the collected calibration panel images, including the internal parameter calibration and the external parameter calibration of the cameras. The internal parameter calibration includes calibrating the focal length, principal point deviation, and distortion parameters of the cameras. The external parameters are the rotation matrix and translation matrix of the cameras relative to the world coordinate system. In this embodiment, the world coordinate system is defined on the left camera of the binocular camera module. For the external parameter calibration in the camera module, the rotation and translation matrix between the two cameras is calibrated. In this embodiment, by identifying the coordinates of the fiducial points on the collected calibration images, the internal and external parameters of the cameras are calibrated simultaneously using the bundle adjustment method. The binocular module calibration technology is an existing technology. The calibration method in this example can refer to the binocular camera calibration technology in the literature "Large-Size Industrial Vision Measurement System" (Liu Jianwei, Liang Jin, Liang Xinhe, etc., Optics and Precision Engineering, 2010). In this embodiment, a calibration panel such as Figure 5 is used. The calibration panel is screen-printed with circular coded fiducial points and circular non-coded fiducial points. The specific size of the calibration panel used during calibration can be determined by the size of the measurement field of view. During the calibration process, the calibration panel adopts the pose as shown in Figure 6 , where the pose includes Figure 6 (a) facing the camera directly, Figure 6 (b) moving forward and facing the camera directly, Figure 6 (c) moving backward and facing the camera directly, Figure 6 (d) rotating clockwise by a certain angle, Figure 6 (e) rotating counterclockwise by a certain angle, Figure 6 (f) tilting backward by a certain angle, Figure 6 (g) tilting forward by a certain angle, Figure 6 (h) rotating 180° and facing the camera module directly.

[0068] S2: Adapter Calibration

[0069] For adapter calibration, the images of the adapters to be calibrated at different positions are collected by the binocular vision module, the fiducial points in each pose of the adapters are reconstructed, and the geometric relationship between the adapters and the pipe ends to be measured is established.

[0070] In this embodiment, the adapter for measuring the position of the pipe end is denoted as the "pipe-end adapter", and the adapter for measuring the positional relationship of the pipe axis is denoted as the "pipe-axis adapter". The "adapter" mentioned below includes the "pipe-end adapter" and the "pipe-axis adapter". Adapter calibration is to establish the relative geometric position relationship between the adapter and the pipe to be measured based on the geometric relationship between the fiducial points in the adapter and the designed geometry of the pipe to be measured. In this embodiment, only the pipe-end adapter is installed and calibrated, and the pipe-axis adapter does not need to be calibrated (in this embodiment, the pipe axis can be directly solved through the pipe-axis adapter without prior calibration).

[0071] Specifically, the calibration implementation process of the pipe end adapter is as follows Figure 7 shown in the figure, including: S21: Install the pipe end adapter by installing the pipe end adapter at the end of the pipe. S22: Image acquisition. Use the calibrated binocular vision module to acquire the adapter image. During the image acquisition process, maintain the relative position relationship between the end of the pipe and the binocular vision module. When changing the position of the adapter, only rotate the calibration point panel of the axial positioning part above the adapter, as shown in Figure 8 shown in the figure, the axis of the pipe axis orientation part is always consistent with the pipe axis, and at least 5 images are acquired. S23: Reconstruct the spatial coordinates of the identification points on the adapter; S24: Determine whether the number of identification points meets the requirements. If it does not meet the requirements, change the position of the adapter and return to step S22 to re-acquire the image. If it meets the requirements, proceed to step S25 and step S26. S25: Fit the identification point data. S26: Establish geometric relationships. Establish the position relationships of the identification points at each position. Fit the axis L0 through the identification points at each position on the axis orientation part, fit the plane P0 through the identification points on the circular surface, and establish the coordinate system of the pipe end adapter according to the axis L0 and the plane P0: Take the intersection point of the axis L0 and P0 as the origin O of the coordinate system of the pipe end adapter A , the axis is the z-axis (Z A ), the straight line passing through the origin and the center of the circle of the circular surface coding identification point is the x-axis (X A ), the axis perpendicular to the two axes is the y-axis (Y A ), and establish the adapter coordinate system according to the right-hand coordinate system principle. According to the design (line-plane) relationship, the coordinates of the center point of the pipe end in the adapter coordinate system are E1(x0, y0, z0).

[0072] S3: Install the pipe axis adapter. Clamp the pipe axis adapter with identification points onto the pipe

[0073] The pipe axis adapter can be easily clamped onto the bent pipe. The identification points on the pipe axis adapter include coded points and non-coded points.

[0074] In this embodiment, the pipe end adapter 30 is fixedly connected to both ends of the pipeline to be measured 10 through its three-jaw chuck type self-positioning structure. The pipe axis adapter wraps the pipeline to be measured 10 between two panels 41 and 42 through an elastic panel 43. Among them, when configuring the number and clamping positions of the pipe axis adapters 40, the following conditions need to be met: At least one pipe axis adapter 40 should be clamped on each straight line segment of the pipeline to be measured 10. At the same time, when using the binocular stereo vision module 20 to take pictures, at least two adjacent pipe axis adapters 40 should be included in the same field of view for subsequent unification of the pipe axis coordinate system. When installing the pipe axis adapter 40, the two surfaces with identification points 50 in each pipe axis adapter 40 should be simultaneously oriented towards the direction of the binocular vision module 20 to ensure that the identification points on the two planes can be reconstructed simultaneously.

[0075] Suppose the direction vector of panel 41 calculated through the identification points is (m1, n1, p1), and the direction vector of panel 42 is (m2, n2, p2). The direction vectors of both panel 41 and panel 42 point to the side of the pipe axis. The plane A of panel 41 fitted through the identification points is expressed as m1*x + n1*y + p1*z + D1 = 0, and the plane B of panel 42 fitted through the identification points is expressed as m2*x + n2*y + p2*z + D2 = 0. The radius of the pipe is r, and the thickness of both panels 41 and 42 is d. Then the pipe axis can be calculated by the following formula:

[0076]

[0077] In the formula, x, y, and z are coordinate representations, and D1 and D2 are constant parameters representing plane A and plane B.

[0078] Of course, other adaptations that can calculate the pipe axis are also applicable.

[0079] S4: Image acquisition;

[0080] Use a binocular vision module to acquire images of the pipeline under test with an adapter. In the images of the pipeline under test with an adapter, the two images need to have a common field of view area of the same adapter.

[0081] Sequentially acquire images of the pipeline under test with an adapter along the extension direction of the pipeline under test. When the camera module acquires images of the pipeline under test, there should be a common field of view area between the two images, and this area includes the pipe axis adapter part. Specifically, as Figure 1 shown, when the binocular vision module acquires an image at the first position, the field of view area 61 includes the pipe axis adapters 401 and 402. When the binocular vision module acquires an image at the second position, the field of view area 62 includes the pipe axis adapters 402 and 403. The images obtained at the two positions will include the pipe axis adapter 402 in the common field of view area.

[0082] S5: Reconstruction of identification points in the adapter;

[0083] Identify the identification points in the adapter images acquired by the binocular vision module, and match and reconstruct each group of adapter identification points through binocular stereo vision technology.

[0084] S6: Matching and alignment of adapter identification points;

[0085] Match and align the adapter identification points reconstructed by the binocular vision module at different positions through the identification points in the common area. Specifically, as Figure 9As shown, after the adapter identification point image at the first position is reconstructed, the three-dimensional coordinates of the points are represented in coordinate system 1 (C1), and the three-dimensional coordinates of the adapter identification points at the second position are represented in coordinate system 2 (C2). Since the three-dimensional coordinates of the identification points in adapter 2 are represented in both coordinate systems C1 and C2 simultaneously, the identification points in adapter 2 are used for point matching. Then, the rotation matrix (R) and translation matrix (T) for aligning coordinate system C2 to coordinate system C1 are obtained. Let the points of the identification points in adapter 2 in C1 be represented as The points of the identification points in adapter 2 in C2 are represented as Then, the rotation matrix and translation matrix can be obtained through optimized calculation using formula (1).

[0086]

[0087] In the formula, R represents the rotation matrix, T represents the translation matrix, and n is the corresponding number of identified identification points.

[0088] All the adapter identification points in coordinate system C2 can be aligned to coordinate system C1 using the rotation matrix and translation matrix obtained through formula (2).

[0089] C1 = R * C2 + T (3) The adapter identification points reconstructed at each position are sequentially matched and aligned, and all the adapter identification points and the calibrated pipe end adapter identification points are unified into coordinate system C1.

[0090] S7: Calculation of pipe geometric features.

[0091] The calculation of pipe geometric features mainly includes calculating the intersection points of pipe axes and pipe end points. As Figure 10 shown, since all the adapter point coordinates in step S6 are aligned to coordinate system C1, all the pipe axes are represented in the same coordinate system. Through the relative geometric relationship between each group of adapters and pipe axes, each group of pipe axes calculated, such as through the geometric relationship between pipe axis adapter 401 and corresponding axis L1 in the example, the corresponding parametric equation of axis L1 is calculated, and through the geometric relationship between pipe axis adapter 402 and corresponding axis L2, the corresponding parametric equation of axis L2 is calculated. The intersection points of two adjacent groups of pipe axes are calculated, such as the intersection point BP1 of axis L1 and axis L2. The reconstruction of all axis intersection points is completed sequentially.

[0092] For the pipe end points, according to the identification points on pipe end adapters 301 and 302, and based on the coordinates of the identification points on the circular surface, the relative position relationship R j 、T j between coordinate system C1 and the coordinate systems of the two pipe end adapters at both ends is established. Then, the coordinates EP j of the center point of the pipe end face can be calculated through the following formula, and the model reconstruction of the entire pipeline to be measured is completed.

[0093] EP j = R j * E j + T j (4)

[0094] where j = 1, 2 respectively represent the serial numbers of both ends of the pipeline to be measured, and E j represents the coordinates of the center point of the pipe end face obtained by calibrating the pipe end adapter in the coordinate system of the pipe end adapter in step S2.

[0095] Among them, by measuring the pipe axis, calculating the intersection point of the pipe axes, and further calculating the bending angle and rotation angle of the pipe; when calculating the pipe axis, the pipe radius or diameter needs to be known; if the advancement of the pipe needs to be calculated, the bending radius of the pipe needs to be known.

[0096] The portable pipe bending measurement device and method proposed in the preferred embodiment of the present invention can simply and quickly complete the pipe axis reconstruction. Among them, the pipe axes are matched and aligned by adapter coding alignment, and the measured length of the pipe is not limited. The measurement position can be for measuring the size of the pipeline to be measured in the pipeline system, or for measuring the pipeline to be measured in offline production or repair of the system; the pipeline to be measured can be for single-piece pipeline measurement or pipeline component measurement, with a wide range of applications.

[0097] Another embodiment of the present invention also provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions prompt the processor to implement the above pipe bending measurement method. For the specific implementation, reference can be made to the method embodiment, which will not be elaborated here.

[0098] The background part of the present invention may include background information about the problems or environment of the present invention, rather than describing the prior art by others. Therefore, the content included in the background art section is not an admission by the applicant of the prior art.

[0099] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, they can also make several substitutions or variations to these described embodiments, and these substitution or variation methods should all be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present 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 can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope defined by the appended claims.

Claims

1. A portable pipe bending measurement device for pipeline measurement, characterized in that, It includes a binocular vision module, a pipe end adapter, and multiple pipe shaft adapters. The pipe end adapters are respectively used for fixedly connecting to the ends of the pipeline to be measured, and the multiple pipe shaft adapters are respectively used for clamping on the pipe shaft between the two ends of the pipeline to be measured. Among them: The pipe end adapter includes an end face positioning part, an axial positioning part, and a first fixing unit. The end face positioning part and the axial positioning part are perpendicularly connected to the first fixing unit. The first fixing unit is used for fixedly connecting with the pipeline to be measured. The end face positioning part is perpendicular to the axis of the pipeline to be measured, and the axial positioning part passes through the axis of the pipeline to be measured. And a plurality of marking points are respectively provided on the end face positioning part and the axial positioning part; The pipe shaft adapter includes a second fixing unit and two panels. A plurality of marking points are respectively provided on the two panels, and the two panels are connected at a predetermined angle to enable the marking points on the two panels to be simultaneously recognized by the binocular vision module. The second fixing unit is used for wrapping the pipeline to be measured between the two panels; The multiple pipe shaft adapters clamped between the two ends of the pipeline to be measured meet the following requirements: at least one of the pipe shaft adapters is clamped on each straight line segment of the pipeline to be measured, and at least two adjacent pipe shaft adapters are included in the same visual field area when the binocular vision module takes pictures.

2. The portable elbow measuring device according to claim 1, wherein The first fixing unit includes a chuck, a jaw driving mechanism, and a plurality of positioning jaws. The jaw driving mechanism is arranged inside the chuck, and the plurality of positioning jaws are connected to the jaw driving mechanism to drive the plurality of positioning jaws to clamp on the inner wall of the pipeline to be measured or clamp on the outer wall of the pipeline to be measured through the jaw driving mechanism; A cylindrical pin is provided at the bottom of the axial positioning part, and the cylindrical pin is coaxial with the axis of the pipeline to be measured and the cylindrical pin is positioned and connected to the chuck.

3. A method for measuring a bent pipe, characterized in that, Using the portable elbow measuring device according to claim 1 or 2 to measure the pipeline to be measured, includes the following steps: S1: Calibrate the binocular vision module; S2: Equip the pipe end adapters at the ends of the pipeline to be measured respectively, and calibrate the pipe end adapters; S3: Equip a plurality of the pipe shaft adapters on the pipe shaft between the two ends of the pipeline to be measured according to preset requirements; S4: Move the binocular vision module along the extension direction of the pipeline to be measured to collect images with the pipe shaft adapter or images with both the pipe shaft adapter and the pipe end adapter at different positions by using the binocular vision module. There is a common visual field area between two adjacent images collected at two positions, and at least one of the pipe shaft adapters is included in the common visual field area; S5: Identify the marking points of the images of the pipe shaft adapter or the images with both the pipe shaft adapter and the pipe end adapter collected in the binocular vision module, and match and reconstruct the marking points. S6: Match and align the tube axis adapter identification points and tube end adapter identification points reconstructed by the binocular vision module at different positions in step S5, so as to unify all the tube axis adapter identification points and all the tube end adapter identification points into the same coordinate system, and then align the tube end adapter identification points unified into the same coordinate system with the calibrated tube end adapter; S7: Reconstruct the overall structure model of the pipeline to be measured according to all the tube axis adapter identification points and all the aligned tube end adapter identification points in the same coordinate system.

4. The elbow pipe measuring method according to claim 3, wherein, The steps for calibrating the tube end adapter in step S2 specifically include: S21: Rotate the axial positioning part of the tube end adapter along the axis of the pipeline to be measured, and collect at least 5 images including the tube end adapter, where the axial positioning part rotates to different angles when each image is collected; S22: Reconstruct the spatial coordinates of the identification points on the tube end adapter; S23: Determine whether the number of identification points reconstructed in step S22 meets the requirements. If not, return to step S21; if it meets the requirements, execute step S24; S24: Fit the identification points and establish geometric relationships.

5. The elbow measurement method according to claim 4, wherein Step S24 specifically includes: Establish the position relationships of the identification points on the tube end adapter when the axial positioning part is at different angles, fit the axis (L0) of the pipeline to be measured through the positions of the identification points on the axial positioning part, fit the plane (P0) of the end face positioning part through the identification points on the end face positioning part, establish the coordinate system of the tube end adapter according to the axis (L0) and the plane (P0), and obtain the coordinates of the center point of the tube end face of the pipeline to be measured in the coordinate system of the tube end adapter.

6. The elbow measurement method according to claim 3, wherein In step S3, a plurality of tube axis adapters are equipped on the tube axis between the two ends of the pipeline to be measured according to preset requirements, where the preset requirements include: at least one tube axis adapter is equipped on each straight line segment of the pipeline to be measured, and at least two adjacent tube axis adapters are included in the same visual field area when the binocular vision module takes pictures.

7. The elbow pipe measurement method according to claim 3, characterized in that, Step S6 specifically includes: S61: Use the identification points in the tube axis adapters in the common visual field area to perform point matching on multiple groups of tube axis adapter identification points, or multiple groups of tube axis adapter identification points and tube end adapter identification points in two images with a common visual field area; S62: Obtain the rotation matrix R and translation matrix T for aligning the coordinate system (C2) in one image to the coordinate system (C1) in another image according to the following formula: wherein, are the same identification points in coordinate system (C1) and coordinate system (C2) respectively, and n is the number of identification points in the tube shaft adapter within the common field of view; S63: Align all the identification points in the coordinate system (C2) to the coordinate system (C1) through the rotation matrix R and translation matrix T obtained in step S62; S64: Repeat steps S61 to S63 to sequentially match and align the tube axis adapter identification points and tube end adapter identification points reconstructed at each position, so as to unify all the tube axis adapter identification points and all the tube end adapter identification points into the same coordinate system, and then align the tube end adapter identification points unified into the same coordinate system with the calibrated tube end adapter.

8. The elbow measurement method according to claim 3, characterized in that, Specifically included in step S7 are as follows: S71: Calculate each set of pipe axes based on the relative geometric relationship between each of the pipe axis adapters and the pipe axis of the pipeline to be measured; S72: Calculate the intersection points of two axes through adjacent groups of pipe axes, and complete the reconstruction of all axis intersection points in sequence; S73: Calculate the coordinates of the center point of the pipe end face of the pipeline to be measured based on all the identified points of the pipe end adapters after alignment.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the steps of the elbow measurement method according to any one of claims 3 to 8.

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