Method and system for detecting installation position deviation of cylindrical part

Abstract

The invention relates to a method and system for detecting installation position deviation of a cylindrical part. The method for detecting the installation position deviation of the columnar part comprises the following steps: acquiring an initial coordinate of a point location on the columnar part to be detected; transmitting the initial coordinate of the point location to a processing terminal; performing coordinate transformation on the initial coordinate of the point location to obtain a relative coordinate of the point location; creating a digital model of the cylindrical part based on the relative coordinates; and the installation position deviation of the cylindrical part is calculated and obtained by carrying out digital measurement on the digital model. According to the method and the system for detecting the installation position deviation of the cylindrical part, the installation position deviation of the cylindrical part is quantitatively measured in a digital manner by customers, and the judgment accuracy and the measurement accuracy of the installation position deviation of the cylindrical part are remarkably improved; and meanwhile, the problem that a complete cylindrical part cannot be measured is effectively solved.

Description

Technical Field

[0001] The present application relates to the field of columnar component installation position deviation detection, and in particular, to a method for detecting columnar component installation position deviation. The present application also relates to a system for detecting columnar component installation position deviation. Background Art

[0002] Nowadays, a large number of columnar parts, such as various tubes, pins, and shafts, are used in various industries, such as aircraft manufacturing. Most of these columnar parts have different shapes and complex structures, and require high installation accuracy. However, during the assembly process, columnar parts are often installed inaccurately or not in place, resulting in radial deviations and axial angles.

[0003] In order to detect such inaccurate installation, the inspectors usually use their personal experience to observe with the naked eye and touch with their hands to find out whether there are problems such as rough assembly and stress installation. Obviously, this method cannot effectively and quantitatively judge and check the installation accuracy of columnar parts. Therefore, an effective means to quantitatively and objectively check the installation accuracy of columnar parts is needed. In addition, in some cases, a part of the columnar part may be blocked, making it impossible to see the complete columnar part, making it difficult for visual inspection and touch inspection to work. Summary of the invention

[0004] The purpose of the present application is to provide a method for detecting the installation position deviation of a columnar component, thereby at least partially solving the problems in the prior art.

[0005] According to one aspect of the present application, a method for detecting the installation position deviation of a columnar part includes the following steps: obtaining the initial coordinates of a point on the columnar part to be detected; transmitting the initial coordinates of the point to a processing terminal; performing a coordinate transformation on the initial coordinates of the point to obtain the relative coordinates of the point; creating a digital model of the columnar part based on the relative coordinates; and calculating and obtaining the installation position deviation of the columnar part by digitally measuring the digital model.

[0006] By adopting the method for detecting the installation position deviation of columnar parts according to the present application, it is possible to quantitatively and digitally measure the installation position deviation of columnar parts, significantly improving the judgment accuracy and measurement precision of the installation position deviation of columnar parts, and effectively solving the problem of being unable to measure complete columnar parts.

[0007] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, as the initial coordinates of the point, the initial coordinates of the point on the outer surface of the columnar part are directly used, or the initial coordinates of the central axis point of the columnar part determined by the coordinates of the point on the outer surface of the columnar part are indirectly used. For a relatively thin columnar part, the initial coordinates of the point on its outer surface can be directly obtained, which can ensure that a straight line representing the columnar part is fitted with sufficient accuracy. For a relatively thick columnar part, the coordinates of the point on its outer surface, such as the circumferential coordinates of a circular tube, can be measured first to determine the initial coordinates of the central axis point. Then the central axis is used to represent the columnar part, thereby also ensuring that a straight line representing the columnar part is fitted with sufficient accuracy. Therefore, the method according to the present application can be applied to both relatively thin columnar parts and relatively thick columnar parts, thereby expanding the scope of application of the method.

[0008] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, the steps of creating a digital model of the columnar part and calculating the installation position deviation of the columnar part are automatically performed by software. Whether creating a digital model of the columnar part or calculating the installation position deviation of the columnar part, it is based on corresponding mathematical methods. These mathematical methods are stored in advance as algorithms in the form of software codes and are automatically called and executed when needed. In this way, the work reliability and efficiency are significantly improved.

[0009] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, the initial coordinates of the point are transmitted to the processing terminal by wired or wireless means. Here, the wired or wireless data transmission method can be flexibly selected according to the actual situation, so that the method of the present application can be flexibly applied to various situations.

[0010] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, the installation position deviation includes the radial deviation and / or axial angle of the columnar part. Three possible situations are covered here: the installation position deviation is only a radial deviation, only an axial angle, and includes both a radial deviation and an axial angle. For the first two situations, the columnar part to be detected and the components installed with it are in the same plane, and for the last situation, the two are in different planes, which involves the distance and angle measurement between skew lines. Therefore, the method of the present application can cope with a variety of different installation situations and effectively measure the vast majority of installation position deviations.

[0011] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, the columnar part includes a tube, a pin, and a shaft. The tube, pin, and shaft here are only examples, not exhaustive. The tube can be a hollow pipe or a solid tube. This shows that the method of the present application can be widely applied to various columnar parts.

[0012] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, the cross section of the columnar part is circular, square or triangular. Similarly, the shapes here are only for enumeration, not for limiting the cross section of the columnar part. The method of the present application is therefore applicable to columnar parts of various cross sections, greatly expanding the scope of application of the method.

[0013] In one embodiment of the method for detecting the installation position deviation of a columnar part of the present application, the measured point is only on a part of the columnar part. This is particularly suitable for the case where the columnar part to be detected is partially blocked, and the complete columnar part cannot be seen and measured. In this case, some points on a small exposed section of the columnar part can be selected as the points to be measured. Since the columnar part itself is straight, it is sufficient to select only some points on a small section (such as a 1 / 3 section), which is sufficient to fit a straight line representing the entire columnar part, thereby reflecting the installation position deviation of the entire columnar part.

[0014] The purpose of the present application is also to propose a system for detecting the installation position deviation of a columnar part, the system comprising: a data acquisition device, the data acquisition device is used to obtain the initial coordinates of a point on the columnar part to be detected; and a processing terminal, the processing terminal having a first module for obtaining the relative coordinates of the point, a second module for creating a digital model of the columnar part and a third module for calculating and obtaining the installation position deviation of the columnar part, wherein the data acquisition device is communicatively connected to the processing terminal.

[0015] The design and advantages described above for the method for detecting installation position deviation of columnar parts according to the present application are also applicable to the system for detecting installation position deviation of columnar parts according to the present application, and will not be elaborated in this application.

[0016] In one embodiment of the system for detecting the installation position deviation of a columnar part of the present application, the data acquisition device includes a laser scanner for inputting the initial coordinates of the point and a reference component used as a reference point of the initial coordinates of the point. It should be noted here that the reference component is not necessary, and in principle other fixed components can also be used as a reference for the reference point of the initial coordinates of the point. However, the use of the reference component can make the measurement convenient and reusable.

[0017] In one embodiment of the system for detecting the installation position deviation of columnar parts of the present application, the laser scanner is a handheld laser scanner. The handheld laser scanner is movable, light and compact, easy to carry, and convenient for measurement, which greatly improves its flexibility and is therefore highly applicable to workplaces. However, the present application is not limited to handheld laser scanners, and large fixed laser scanners may also be used as needed. In addition, the laser has a high degree of concentration and is not easy to diverge, which can improve the measurement accuracy, and therefore the scanner is preferably a laser scanner. Of course, the present application is not limited to this, and in principle other lights may also be used. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Other designs and advantages of a method for detecting installation position deviation of a columnar component and a system for detecting installation position deviation of a columnar component implementing the method according to the present application will be described in detail below with reference to the accompanying drawings by way of embodiments.

[0019] Figure 1 A flow chart of a method for detecting installation position deviation of a columnar part according to the present application is shown;

[0020] Figure 2 An example of deviation in the installation position of a columnar part is shown;

[0021] Figure 3 An example of detecting the installation position deviation of a thin square tube using the method according to the present application is shown;

[0022] Figure 4 An example of detecting the installation position deviation of a thick round pipe using the method according to the present application is shown;

[0023] Figure 5 A block diagram of a system for detecting installation position deviation of a column-type part according to the present application is shown. DETAILED DESCRIPTION

[0024] See also Figure 1 , which shows a flow chart of a method for detecting installation position deviation of a columnar part according to the present application. The columnar part here can be, for example, a tube, a pin, a shaft, but other columnar parts are not excluded. The tube can be a hollow tube or a solid tube. For example, the cross-section of the columnar part can be circular, square or triangular. However, the present application is not limited to columnar parts of these cross-sectional shapes. The columnar part can be made of metal such as steel, iron, copper, etc., or it can be made of plastic, especially PVC, etc. Of course, the columnar part can also be made of other materials.

[0025] When installing a columnar part, we strive to align it with the components installed with it, such as other columnar parts or bases, so that the two or their central axes are in a straight line. However, deviations are likely to occur during the actual installation process. Such deviations include radial deviations and / or axial angles of the columnar part. As the name implies, the axial direction of a columnar part is its longitudinal direction, and the radial direction is the direction perpendicular to the longitudinal direction. Figure 2 , radial deviation indicates that the two are misaligned, making them or their axes at a certain distance from each other, and axial angle means skew. In a more serious case, there is both radial deviation and axial angle. At this time, the two are in different planes, which involves the distance and angle measurement between non-coplanar straight lines. This application is aimed at the above situation, to determine whether there is deviation in the installation of columnar parts and the type of deviation, and to quantitatively measure the degree of deviation.

[0026] According to the method of the present application, first in the first step S1, the initial coordinates of the points on the cylindrical part to be detected are obtained. For thin cylindrical parts, such as Figure 3 The thin square tube shown in the figure can directly measure any two points on the outer surface of the cylindrical part that are a certain distance apart along its axial direction, such as points B and C, and obtain the initial coordinates of these points. Since this cylindrical part is relatively thin, the two points on its outer surface can accurately fit a straight line representing the cylindrical part. At this time, the initial coordinates of the points to be measured are the initial coordinates of points B and C. In the case of a relatively thick cylindrical part, for example, Figure 4 For the thick round tube shown in the figure, it is necessary to use any two points on the axis O at a certain distance, such as O1 and O2, to fit a straight line representing the cylindrical part accurately enough. To this end, it is necessary to first measure the initial coordinates of the three points E1, E2, E3 and F1, F2, F3 on the outer circle of the cross section where O1 and O2 are located, and then use the mathematical principle of determining a circle based on three points to deduce the initial coordinates of the center of the circle where they are located, that is, O1 and O2. In this case, the initial coordinates of the points to be measured are the coordinates of the points E1, E2, E3 and F1, F2, F3 on the outer surface of the cylindrical part to determine the initial coordinates of the points O1 and O2 on the axis O of the cylindrical part. As for the reason for using a straight line to represent the cylindrical part, it will be introduced below.

[0027] It should be pointed out that when obtaining the initial coordinates of the points on the cylindrical part to be detected, the present application is not limited to the selection of two points. To be precise, any number of points more than two can also be selected to form a point cloud. In addition, in some cases, a portion of the cylindrical part to be detected may be blocked, making it impossible to see and measure the complete cylindrical part. In this case, some points on the exposed section of the cylindrical part can be selected. Since the cylindrical part itself is straight, only some points on a certain section (such as 1 / 3 of the section) are sufficient to fit a straight line representing the entire cylindrical part, thereby reflecting the installation position deviation of the entire cylindrical part.

[0028] According to the present application, after obtaining the initial coordinates of the points on the columnar part to be detected, in the second step S2, the initial coordinates of the points are transmitted to the processing terminal 20. Here, according to the actual application, wired or wireless transmission can be flexibly selected. The processing terminal 20 can be a computer, a smart phone, an iPad, etc., and the present application does not limit this.

[0029] Then, in the third step S3, the initial coordinates of the point are transformed to obtain the relative coordinates of the point. Specifically, the initial coordinates of the point on the outer surface of the columnar part or the initial coordinates of the point on the central axis of the columnar part determined by the coordinates of the point on the outer surface of the columnar part are converted into corresponding relative coordinates. It should be noted here that the initial coordinates of the point on the outer surface of the columnar part are measured relative to the reference object at the installation site of the columnar part, and the relative coordinates are converted in the processing terminal 20. There is no reference object in the processing terminal, and no reference object is required. Only the relative coordinates between the columnar parts are needed to derive the digital model of the columnar part to be detected, which provides a basis for subsequent calculation and obtaining the installation position deviation. For this purpose, it is necessary to establish a corresponding three-dimensional coordinate system in the processing terminal, which includes, for example, the horizontal axis x, the longitudinal axis y and the vertical axis z.

[0030] After obtaining the relative coordinates of the points, in the fourth step S4, a digital model of the columnar part is created based on the relative coordinates. Specifically, for the columnar part to be detected, based on the relative coordinates of at least two points located on the columnar part or on its central axis, a mathematical equation of a straight line determined by the two points can be obtained, that is, a digital model is established for the straight line, and a straight line representing the columnar part to be detected is created on the three-dimensional coordinate system in the processing terminal according to the digital model. In the same way, a digital model of a component installed with the columnar part to be detected, such as other columnar parts or a base, is established, and another straight line is created on the three-dimensional coordinate system to represent the component installed with the columnar part to be detected. Thus, a digital model of the columnar part to be detected and the components installed with it, that is, two straight lines on the three-dimensional coordinate system, is obtained.

[0031] Finally, in the fifth step S5, the installation position deviation of the columnar part to be detected is calculated and obtained by digitally measuring the created digital model. Specifically, when the two straight lines are aligned with each other, that is, they are actually on the same straight line, it can be determined that there is no installation position deviation of the columnar part to be detected, otherwise there must be an installation position deviation. In the case of installation position deviation, if the two straight lines are in the same plane, when the two straight lines are parallel, it can be determined that the columnar part to be detected only has a radial deviation, and when the two straight lines intersect, it can be determined that the columnar part to be detected only has an axial angle, see Figure 2 If the two straight lines are not in the same plane, that is, they are two straight lines in different planes, it can be determined that the cylindrical part to be inspected has both radial deviation and axial angle.

[0032] The following first introduces the case where only radial deviation exists. Assuming that both straight lines are parallel to the horizontal axis of the three-dimensional coordinate system, for example, the vertical coordinates of any two points with the same horizontal coordinates on the two straight lines can be subtracted to obtain the distance between the two straight lines. Similarly, if both straight lines are parallel to the vertical axis of the three-dimensional coordinate system, for example, the horizontal coordinates of any two points with the same vertical coordinates on the two straight lines can be subtracted to obtain the distance between the two straight lines. If the two straight lines are neither parallel to the horizontal axis nor to the vertical axis, for example, a third straight line perpendicular to the two straight lines can be made to intersect the two straight lines at one point, and then the horizontal coordinates of the two intersection points are subtracted to obtain the horizontal coordinate difference, and their vertical coordinates are subtracted to obtain the vertical coordinate difference, and then the horizontal coordinate difference and the vertical coordinate difference are regarded as the two right-angled sides of a right triangle, and the Pythagorean theorem is used to calculate the hypotenuse of the right triangle, which is the distance between the two straight lines. The distance between the two straight lines is the size of the radial deviation of the cylindrical part to be tested.

[0033] Next, we discuss the case where only the axial angle exists. In order to obtain the axial angle, for example, the angles between the two straight lines and the horizontal axis or the vertical axis can be calculated respectively, and then the two obtained angles are subtracted to obtain the size of the axial angle. Of course, other methods can also be used to calculate the axial angle.

[0034] For the case where there is both radial deviation and axial angle, it actually involves the problem of finding the distance and angle between two straight lines in different planes (that is, in different planes). For example, in order to find the angle between two different straight lines, the direction vectors of the two straight lines can be set to be and Find the dot product of two direction vectors: Where θ is the two direction vectors and The angle of and Two direction vectors and The modulus of , so the included angle can be obtained as: In order to obtain the distance d between two non-coplanar straight lines, for example, the following formula can be used:

[0035]

[0036] It should be noted that the various mathematical methods listed above are all examples. In order to obtain the corresponding distance or angle, any suitable method can be used, and the present application is not limited to this. In addition, these methods for obtaining the corresponding distance or angle can be stored in the processing terminal 20 as algorithms in advance, and after obtaining the corresponding relative coordinates, they are automatically executed by the software on the processing terminal 20. Furthermore, the creation of the digital model of the columnar part and the calculation of its installation position deviation are based on the corresponding mathematical methods. These mathematical methods are stored in advance as algorithms in the form of software codes, and are automatically retrieved and executed when needed. This can significantly improve work reliability and efficiency.

[0037] Another aspect of the present application relates to a system 100 for detecting installation position deviation of a columnar component. Figure 5 , the system 100 includes a data acquisition device 10 and a processing terminal 20. The data acquisition device 10 is used to obtain the initial coordinates of the points on the columnar part to be detected, and the processing terminal 20 has a first module 21 for obtaining the relative coordinates of the points, a second module 22 for creating a digital model of the columnar part, and a third module 23 for calculating and obtaining the installation position deviation of the columnar part, wherein the data acquisition device 10 is communicatively connected to the processing terminal 20. It can be seen that the system 100 can be used to implement the method for detecting the installation position deviation of the columnar part according to the present application. Specifically, when the system 100 is working, the data acquisition device 10 measures and enters the initial coordinates of the points on the outer surface of the columnar part, and the initial coordinates are then transmitted to the processing terminal 20 in a wired or wireless manner. For thin cylindrical parts, the first module 21 of the processing terminal 20 directly transforms the initial coordinates of the points on the outer surface of the cylindrical part to obtain the relative coordinates of the points; for thick cylindrical parts, the first module 21 determines the initial coordinates of the central axis point of the cylindrical part according to the coordinates of the points on the outer surface of the cylindrical part, and transforms the initial coordinates of the central axis point to obtain the relative coordinates of the central axis point. Next, the second module 22 of the processing terminal 20 calls the corresponding software, and based on the relative coordinates, automatically creates a digital model of the cylindrical part according to the pre-set and stored algorithm. Subsequently, the third module 23 of the processing terminal 20 performs digital measurement on the digital model to calculate and obtain the installation position deviation of the cylindrical part, such as radial deviation and / or axial angle.

[0038] The system of the present application includes the various designs and advantages described above for the method for detecting installation position deviation of columnar parts according to the present application, and correspondingly also apply to the system according to the present application, which will not be described in detail in the present application.

[0039] In one embodiment of the system according to the present application, the data acquisition device 10 includes a laser scanner 11 for recording the initial coordinates of the point and a reference component 12 used as a reference point for the initial coordinates of the point. When obtaining the initial coordinates of the cylindrical part to be inspected, the laser scanner 11 is used to scan the relevant points to record the initial coordinates of the point. Figure 3 and Figure 4 It should be noted that when obtaining the initial coordinates, a reference object is required as a reference point. For example, a base A near the columnar part to be inspected can be used. Figure 3 As shown. Alternatively, a dedicated reference component 12 can also be used, which is installed near the cylindrical part to be detected when in use. This makes it more convenient to obtain the initial coordinates. In addition, the reference component 12 can be reused many times, thereby significantly improving the simplicity of measurement and reducing the measurement cost.

[0040] In one embodiment of the system according to the present application, the laser scanner 11 is a handheld laser scanner. This laser scanner is small and portable, easy to carry and measure, highly flexible, and can be adapted to various work environments. Of course, the present application is not limited to handheld laser scanners, and large fixed laser scanners can also be used as needed. The present application is not limited to this.

[0041] In one embodiment of the system according to the present application, the laser scanner 11 is a blue light scanning laser scanner. Most laser scanners use the principle of light reflection, that is, they use the light reflected by the columnar parts to be detected. In particular, for columnar parts made of metal materials, the reflection effect of blue light is good, which can improve the measurement accuracy. In addition, laser light is not easy to diverge due to its high concentration, which can improve the measurement accuracy. It goes without saying that, depending on the specific application, other lights can also be used in principle, and the present application is not limited to this.

[0042] The method and system according to the present application can realize high-precision measurement of columnar parts, especially fluid pipelines in aircraft, when the entire shape of the columnar parts cannot be completely scanned (for example, scanning 1 / 3 of the outer surface of the columnar parts), such as in a small space with insufficient light. The method and system according to the present application can replace the traditional visual and hand-touch detection methods, realize digital reproduction of actual columnar parts such as pipelines, truly reflect the shape and position relationship of columnar parts on site, and quantitatively determine the installation position deviation by digitally measuring the digital model of the columnar parts, thereby reducing human factors and dependence on people's experience. Practice shows that the method and system for detecting the installation position deviation of columnar parts according to the present application can achieve a radial deviation accuracy of more than 0.1 mm and an axial angle accuracy of more than 1° in the installation of columnar parts.

[0043] Some embodiments of the present application have been introduced for the purpose of illustration, but the present application is not limited to these embodiments. Those skilled in the art may also think of many modifications and variations. Therefore, these embodiments are selected and described in order to better illustrate the principles and practical applications of the present application and to enable those skilled in the art to understand the content thereof, that is, without departing from the spirit of the present application, all modifications and variations made will fall within the scope of protection of the present application as defined by the appended claims.

Claims

1. A method for detecting the installation position deviation of a columnar part, comprising the following steps: Obtain the initial coordinates of the points on the cylindrical part to be inspected; transmitting the initial coordinates to a processing terminal (20); Performing coordinate transformation on the initial coordinates to obtain the relative coordinates of the point; Based on the relative coordinates, creating a digital model of the columnar part; The installation position deviation of the columnar part is calculated and obtained by digitally measuring the digital model.

2. The method according to claim 1, in, As the initial coordinates, the initial coordinates of a point on the outer surface of the columnar part are directly used, or the initial coordinates of a point on the center axis of the columnar part determined by the coordinates of a point on the outer surface of the columnar part are indirectly used.

3. The method according to claim 2, in, The steps of creating a digital model of the columnar part and calculating the installation position deviation of the columnar part are automatically performed using software.

4. The method according to claim 1, in, The initial coordinates of the point are transmitted to the processing terminal (20) by wired or wireless means.

5. The method according to any one of claims 1 to 4, in, The installation position deviation includes a radial deviation and / or an axial angle of the columnar component.

6. The method according to any one of claims 1 to 4, in, The columnar parts include tubes, pins and shafts.

7. The method according to any one of claims 1 to 4, in, The cross section of the columnar part is circular, square or triangular.

8. The method according to any one of claims 1 to 4, in, The point to be measured is located only on a portion of the cylindrical part.

9. A system (100) for detecting installation position deviation of a columnar component, for implementing the method according to any one of the preceding claims, include: A data acquisition device (10) is used to obtain the initial coordinates of points on the columnar part to be inspected; and A processing terminal (20) having a first module (21) for acquiring the relative coordinates of the point, a second module (22) for creating a digital model of the columnar part, and a third module (23) for calculating and obtaining the installation position deviation of the columnar part, Wherein, the data acquisition device (10) is communicatively connected to the processing terminal (20).

10. The system according to claim 9, in, The data acquisition device (10) comprises a laser scanner (11) for recording the initial coordinates of the point and a reference component (12) used as a reference point for the initial coordinates of the point.

11. The system according to claim 10, in, The laser scanner is a handheld laser scanner.

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