Conveying belt thickness measuring device and method and conveyor

Abstract

The invention belongs to the technical field of machine vision nondestructive testing, and particularly relates to a conveying belt thickness measuring device and method and a conveyor. Structured light is projected to a conveying belt through the device, a picture with the structured light on the conveying belt is obtained, sub-pixel processing is conducted on the picture, and a set of two-dimensional coordinates is obtained; a group of two-dimensional coordinates are converted into arithmetic information S through calculation, real thickness information on the conveying belt is obtained, the group of arithmetic information S is corrected, and full-section thickness information of the conveying belt is obtained. According to the method, the visual measurement technology and the linear measurement technology are fused, and the real thickness of the conveying belt is combined with the visual measurement technology; according to the method, the thickness of the whole section of the conveying belt can be accurately measured, parallax and measurement errors possibly caused by factors such as illumination in a traditional method are reduced, high practicability, reliability and safety are achieved, and powerful technical support is provided for maintenance and management of a mining industry conveying system.

Description

Technical Field

[0001] The invention belongs to the technical field of machine vision nondestructive testing, and in particular relates to a conveyor belt thickness measuring device and method and a conveyor. Background Art

[0002] In the field of bulk material transportation, conveyor belts are important material transportation equipment. Their operating status and structural integrity directly affect production efficiency and safety. Among them, conveyor belt thickness monitoring is one of the key factors to ensure the stable operation of the conveying system. Traditional thickness monitoring methods mainly rely on manual detection or simple mechanical measuring instruments. These methods are not only inefficient, but also unable to adapt to the precise measurement requirements under large width, full section and complex working conditions.

[0003] With the development of industrial automation and informatization, visual measurement technology has gradually been applied to the field of conveyor belt thickness monitoring due to its non-contact and high efficiency characteristics. For example, the Chinese invention patent number CN202322294174.0 discloses a conveying distance measurement mechanism for a conveyor. Although the measurement mechanism can efficiently measure the thickness of the conveyor belt, it is difficult to achieve high-precision and high-stability measurement results due to factors such as lighting conditions and environmental interference. Summary of the invention

[0004] In view of this, the present invention provides a conveyor belt thickness measuring device and method and a conveyor to solve the technical problem of inaccurate conveyor belt thickness measured by the conveyor belt thickness measuring method and device in the prior art.

[0005] To achieve the above objectives, this application adopts the following scheme:

[0006] A conveyor belt thickness measuring device comprises a layout frame arranged on both sides of the conveyor belt, and an image capturing device, a specific point thickness acquiring device, a lateral coordinate capturing device and a control module arranged on the layout frame;

[0007] The image capture device includes a laser generator and an industrial camera arranged in pairs with the conveyor belt as the center, the laser generator is arranged on the arrangement frame and is used to project a structured light band on the conveyor belt, and the industrial camera is used to obtain a photo of the conveyor belt with the structured light band;

[0008] The specific point thickness acquisition device cooperates with the arrangement frame to move along the width direction of the conveyor belt, and the specific point thickness acquisition device is used to acquire the thickness information of the conveyor belt;

[0009] The transverse coordinate capturing device is used to capture the transverse coordinate information of the specific point thickness acquiring device;

[0010] The control module is electrically connected to the industrial camera, the specific point thickness acquisition device, and the horizontal coordinate capture device, and is used to process the photos, the thickness information and the horizontal coordinate information, and calculate and output the full-section thickness information.

[0011] Preferably, it also includes an obstacle avoidance device. The obstacle avoidance device includes a pair of obstacle avoidance components symmetrically arranged on the arrangement frame with the conveyor belt as the center, the obstacle avoidance component includes a transverse mounting frame, an obstacle detection component, a servo motor group and a pair of longitudinal electric telescopic cylinders. The pair of longitudinal electric telescopic cylinders are respectively arranged on the arrangement frame in the vertical direction and are respectively located on both sides of the conveyor belt. The transverse mounting frame is horizontally arranged and connected between the telescopic ends of the pair of longitudinal electric telescopic cylinders. The obstacle detection component is arranged on the transverse mounting frame, and the fixed end of the servo motor group is arranged on the arrangement frame. The industrial camera is arranged on the arrangement frame through the servo motor group, and the industrial camera is arranged at the telescopic end of the servo motor group. The obstacle detection component, the servo motor group, and the pair of longitudinal electric telescopic cylinders are all electrically connected to the control module.

[0012] Preferably, the specific point thickness acquisition device includes a displacement screw and a displacement sensor arranged in pairs with the conveyor belt as the center, the displacement screw is arranged on the placement rack, the displacement sensor is arranged at the moving end of the displacement screw, and the displacement screw is used to drive the displacement sensor to move along the width direction of the conveyor belt.

[0013] Preferably, the transverse coordinate capture device includes an ultrasonic sensor arranged on one side of the conveyor belt, the ultrasonic sensor is arranged on the arrangement frame, the ultrasonic sensor is electrically connected to the control module, and is used to detect the position of the displacement sensor and send the transverse coordinate information to the control module.

[0014] A conveyor comprises any one of the conveyor belt thickness measuring devices described above, wherein the conveyor belt thickness measuring device is used to detect the full-section thickness of the conveyor belt on the conveyor.

[0015] A method for measuring the thickness of a conveyor belt comprises the following steps:

[0016] S1: Obtaining contour information K of the conveyor belt: projecting structured light bands onto the upper and lower surfaces of the conveyor belt respectively, taking photos of the structured light bands on the upper and lower surfaces of the conveyor belt respectively, and performing sub-pixel processing on the photos to obtain image information, and calculating the contour information K by an image algorithm based on the image information. The contour information K is a set of two-dimensional pixel coordinates of a cross section corresponding to the surface of the conveyor belt covered by the structured light band, and the contour information K has a number of transverse coordinate values ​​x and a number of longitudinal pixel values ​​y;

[0017] S2: Calculate the arithmetic information S of the conveyor belt: calculate the mapping relationship t of the pixel values, and convert the contour information K into a set of arithmetic information S of the corresponding cross section of the structured light belt according to the mapping relationship t, each of the arithmetic information S has a transverse coordinate value w* and a longitudinal thickness value h*;

[0018] S3: Obtaining correction information J0 of the correction point: Obtaining the true thickness h of any point on the conveyor belt, and obtaining the transverse coordinate w of the point on the conveyor belt along the width direction of the conveyor belt. This point is the correction point, and the true thickness h and the transverse coordinate w are the correction information J0;

[0019] S4: Acquire arithmetic information S0 of the correction information J0: Among the set of arithmetic information S, the arithmetic information w=w* is the arithmetic information S0 of the correction point J0, and the arithmetic information S0 has a horizontal coordinate value w*0 and a vertical thickness value h*0;

[0020] S5: Calculate the corrected thickness H: calculate the pixel difference D through the contour information K and the true thickness h, calculate the corrected thickness H according to the mapping relationship t and the pixel difference D, add each longitudinal thickness value h* to the product value of the pixel difference D and the mapping relationship t, and obtain a set of corrected thicknesses H, which is the full-section thickness information.

[0021] Preferably, the structured light belt is a pair of straight laser beams located in the same cross section projected onto the upper and lower surfaces of the conveyor belt, and the straight laser beams cover the entire width of the conveyor belt.

[0022] Preferably, step S2 comprises the following steps:

[0023] S21: The specific steps of solving the mapping relationship t are: the computer obtains the pixel width L* of the structured light band in the image information, the unit is mm, and the computer obtains the field of view width L of the structured light band in the photo, the unit is pix, then the mapping relationship t is In the mapping relationship t, b is a sub-pixel processing effect coefficient, and the unit of the mapping relationship t is mm / pix;

[0024] S22: Convert the contour information K into a set of arithmetic information S according to the mapping relationship t, and the conversion formula of the horizontal coordinate value w* and the longitudinal thickness value h* of each arithmetic information S is:

[0025] Preferably, step S5 comprises the following steps:

[0026] S51: Obtain the contour information K0 corresponding to the correction point: In a set of contour information K, The contour information is the contour information K0 corresponding to the correction point;

[0027] S52: Calculate the longitudinal pixel value y0 corresponding to the true thickness h according to the mapping relationship t and the true thickness h. The solution formula for the longitudinal pixel value y0 is: Replace the vertical pixel value in the contour information K0 with the vertical pixel value y0;

[0028] S53: The solution formula of the pixel difference D is: D=y-y0, the unit of the pixel difference D is pix, where y is the remaining vertical pixel values ​​in the group of contour information K where the vertical pixel value y0 is located.

[0029] Preferably, the method further includes an adaptive obstacle avoidance step S6, wherein the adaptive obstacle avoidance step includes the following steps:

[0030] S61: Perform ultrasonic detection on the front, rear and top of the conveyor belt respectively. If an obstacle is found on the conveyor belt, proceed to S62; otherwise, jump to S1;

[0031] S62: Generate the obstacle avoidance signal, and the conveyor belt thickness measuring device adjusts its working posture in response to the obstacle avoidance signal to avoid the obstacle.

[0032] The technical solution adopted in this application can achieve the following beneficial effects:

[0033] The specific point thickness acquisition device in the conveyor belt thickness measuring device provided by the present invention can accurately measure the thickness information of the specific point of the conveyor belt, the transverse coordinate capture device captures the transverse coordinate information of the specific point thickness acquisition device, the image capture device can fully acquire the image information of the conveyor belt, and the control module calculates and corrects the thickness information, the transverse coordinate information and the image information, and outputs the full-section thickness information and the corrected image information. The specific point thickness acquisition device can accurately measure the actual thickness of the specific point, while the image capture device provides comprehensive profile information (image information). The combination of the two provides double guarantee for accurate measurement, reducing the parallax and measurement errors that may occur in traditional methods;

[0034] The purpose of the present invention is to provide an accurate and efficient conveyor belt thickness measurement method. First, structured light is projected onto the conveyor belt, and a photo with structured light on the conveyor belt is obtained. The photo is subjected to sub-pixel processing to obtain a set of two-dimensional coordinates (contour information K). The set of two-dimensional coordinates is converted into arithmetic information S by calculation. Since errors may occur in the process of photographing, sub-pixel processing, image recognition and calculation, all errors are combined to finally result in a large error between the arithmetic information S and the actual situation. Therefore, the present application obtains the true thickness h and the lateral coordinate w of the correction point on the corresponding cross section of the conveyor belt, and uses the lateral coordinate w to find the corresponding cross section with the same lateral coordinate. The arithmetic thickness is the arithmetic thickness value of the correction point, and the pixel difference D between the longitudinal pixel value y0 of the correction point in the image information and the longitudinal pixel value y of the same section is obtained. Finally, it is only necessary to add the difference calculated using the pixel difference D to a corresponding set of arithmetic information to calculate the correction thickness H that is closer to the actual thickness of the conveyor belt. The present application improves the existing visual measurement technology by utilizing the characteristic that although there is a large error between the visual measurement and the actual value, the difference between the same group of data is basically consistent with the actual situation. This provides a conveyor belt thickness measurement method that is non-contact, efficient in measurement, and more accurate than the visual measurement results of the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure of the device of the present invention;

[0036] Figure 2 It is a schematic diagram of the local structure of the device of the present invention;

[0037] Figure 3 This is a schematic diagram of the irradiation of a laser generator in the present invention;

[0038] Figure 4 It is a performance parameter diagram of a laser generator in the present invention;

[0039] Figure 5 This is a schematic diagram of the installation angle of the industrial camera in the present invention;

[0040] Figure 6 It is a schematic diagram of the process of the present invention;

[0041] Figure 7 Schematic diagram of the image processing process in the method of the present invention;

[0042] Figure 8 Schematic diagram of image processing effect in the method of the present invention;

[0043] Fig. 9 A schematic diagram of a specific case of correction calculation in the method of the present invention;

[0044] Fig.10A diagram of a visual user interface developed in the method of the present invention;

[0045] Fig.11 This is a graph of measured image data in the method of the present invention.

[0046] In the figure, a conveyor belt 100, a layout frame 200, a straight laser generator 310, an industrial camera 320, a structured light belt 330, a laser beam 331, a specific point thickness acquisition device 400, a displacement screw 410, a displacement sensor 420, an ultrasonic sensor 510, a control module 600, a transverse mounting frame 711, an obstacle detection component 712, a servo motor group 713, and an electric lifting and retracting cylinder 714 are shown. DETAILED DESCRIPTION

[0047] In order to facilitate the understanding of the present application, the present application will be described more comprehensively below in conjunction with the accompanying drawings. And the preferred implementation of the present application is given. However, the present application can be implemented in many different forms and is not limited to the implementation described herein. On the contrary, the purpose of providing these implementations is to make the disclosure of the present application more thoroughly and comprehensively understood.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0049] Please see Figures 1 to 5 , a conveyor belt 100 thickness measuring device, comprising a layout frame 200 arranged on both sides of the conveyor belt 100, and an image capturing device, a specific point thickness acquiring device 400, a lateral coordinate capturing device and a control module 600 arranged on the layout frame 200;

[0050] The image capture device includes a laser generator 310 and an industrial camera 320 arranged in pairs with the conveyor belt 100 as the center. The laser generator 310 is arranged on the arrangement frame 200 and is used to project a structured light band 330 on the conveyor belt 100. The industrial camera 320 is used to obtain a photo of the conveyor belt 100 with the structured light band 330.

[0051] The specific point thickness acquisition device 400 cooperates with the arrangement frame 200 to move along the width direction of the conveyor belt 100, and the specific point thickness acquisition device 400 is used to acquire the thickness information of the conveyor belt 100;

[0052] The transverse coordinate capturing device is used to capture the transverse coordinate information of the specific point thickness acquiring device 400;

[0053] The control module 600 is electrically connected to the industrial camera 320, the specific point thickness acquisition device 400, and the horizontal coordinate capture device, and is used to process the photos, the thickness information and the horizontal coordinate information, and calculate and output the full-section thickness information.

[0054] In a specific implementation process, the arrangement frame 200 is constructed of aluminum profiles, aluminum angle codes, hexagonal bolts, and trapezoidal nuts. The size, specifications, and shape of the arrangement frame 200 can be formulated according to the size and shape of the conveyor; the one-line laser generator 310, the servo motor group 713, and the industrial camera 320 are a pair (two), respectively, and are located on both sides of the upper and lower surfaces of the conveyor belt 100; the installation angle of the industrial camera 320 is between 30° and 70°, and the field of view of the industrial camera 320 should cover more than 90% of the width of the conveyor belt 100, and the focal length and exposure settings of the industrial camera 320 are adjusted to ensure the clarity of the image; the arrangement frame 200 is arranged on both sides of the conveyor, and the positions of the image capture device, the specific point thickness acquisition device 400, the horizontal coordinate capture device, and the control module 600 arranged on the arrangement frame 200 can be set by technicians in this field according to actual conditions.

[0055] When in use, first, a pair of the straight laser generators 310 project a straight laser beam 331 (structured light) onto the upper and lower surfaces of the conveyor belt 100 respectively; the straight laser beams 331 on the upper and lower surfaces of the conveyor belt 100 are in a plane, and the plane is the measurement surface of the entire cross-section of the conveyor belt 100; the straight laser beams 331 cover the entire width of the conveyor belt 100, and the structured light band 330 is generated on the conveyor belt 100 for the pair of industrial cameras 320 to collect, obtain the image information, and preliminarily obtain the contour information of the surface of the conveyor belt 100; when the obstacle detection element 712 detects an obstacle on the conveyor belt 100 After the obstacle is detected, obstacle avoidance information is generated. After the obstacle avoidance component is adaptively extended and retracted, the position of the straight laser generator 310 located on the horizontal mounting frame 711 is changed, resulting in a change in the position of the structured light band 330 projected onto the conveyor belt 100. The structured light will be displaced within the field of view of the industrial camera 320, which will affect the consistency of the photos (i.e., image information) captured by the industrial camera 320. Therefore, the industrial camera 320 needs to correct its own field of view to continue to aim at the structured light. The correction method of the industrial camera 320 is to rotate and shrink according to the height of the straight laser, and the driving component for its rotation and shrinking is the servo motor group 713.

[0056] When in use, first, confirm that the conveyor belt 100 on the conveyor is working normally, and then, a pair of the straight laser generators 310 project a straight laser beam 331 (structured light) onto the upper and lower surfaces of the conveyor belt 100 respectively; the straight laser beams 331 on the upper and lower surfaces of the conveyor belt 100 are in a plane, and the plane is the measurement surface of the full cross-section of the conveyor belt 100; the straight laser beam 331 covers the entire width of the conveyor belt 100, and the industrial camera 320 takes pictures of the conveyor belt 100 (with the straight laser beam 331) respectively, and transmits the pictures to the control module 600, and the control module 600 performs sub-pixel processing on the pictures to obtain image information; the specific point thickness acquisition device 400 and the arrangement frame 200 moves along the width direction of the conveyor belt 100 to obtain the thickness information of a certain point of the conveyor belt 100. It should be noted that the thickness information is the real thickness information of the conveyor belt 100; at the same time, the transverse coordinate capture device captures the transverse coordinate information of the specific point thickness acquisition device 400, that is, the transverse coordinate that can correspond one-to-one with the above-mentioned thickness information, and sends the thickness information and the transverse coordinate information of the corresponding point to the control module 600; the control module 600 receives the image information, the thickness information and the transverse coordinate information, and processes them, calculates and transmits the full-section thickness information and the corrected image information through an algorithm, and the output method can be any graphic form that is easy for users to quickly understand.

[0057] Beneficial effects: The specific point thickness acquisition device 400 in the conveyor belt thickness measurement device provided by the present invention can accurately measure the thickness information of the specific point of the conveyor belt 100, the transverse coordinate capture device captures the transverse coordinate information of the specific point thickness acquisition device 400, the image capture device can fully acquire the image information of the conveyor belt 100, and the control module 600 calculates and corrects the thickness information, the transverse coordinate information and the image information, and outputs the full-section thickness information and the corrected image information. The specific point thickness acquisition device 400 can accurately measure the actual thickness of the specific point, while the image capture device provides comprehensive profile information (image information). The combination of the two provides double guarantee for accurate measurement and reduces the parallax and measurement errors that may occur in traditional methods.

[0058] In the above implementation process, during the thickness detection of the conveyor belt 100, some obstacles are brought to the conveyor belt 100. These obstacles will block the laser beam 331 emitted by the one-line laser, and will also interfere with the industrial camera 320 taking photos of the structured light band 330. In a possible embodiment, an obstacle avoidance device is also included. The obstacle avoidance device includes a pair of obstacle avoidance components symmetrically arranged on the arrangement frame 200 with the conveyor belt 100 as the center. The obstacle avoidance component includes a transverse mounting frame 711, an obstacle detection member 712, a servo motor group 713 and a pair of longitudinal electric telescopic cylinders 714. The pair of longitudinal electric telescopic cylinders are respectively arranged on the arrangement frame 200 along the vertical direction. 00, and are respectively located on both sides of the conveyor belt 100, the transverse mounting frame 711 is horizontally arranged and connected between the telescopic ends of the pair of longitudinal electric telescopic cylinders, the obstacle detection member 712 is arranged on the transverse mounting frame 711, and the fixed end of the servo motor group 713 is arranged on the arrangement frame 200, the industrial camera 320 is arranged on the arrangement frame 200 through the servo motor group 713, and the industrial camera 320 is arranged at the telescopic end of the servo motor group 713, the obstacle detection member 712, the servo motor group 713, and the pair of longitudinal electric lifting and retracting cylinders 714 are all electrically connected to the control module 600. In a specific implementation process, the obstacle detection component 712 can obtain the spatial coordinate information of the obstacle appearing on the conveyor belt 100, and generate corresponding obstacle avoidance information of the obstacle according to the spatial coordinate information of the obstacle, and input the obstacle avoidance information into the longitudinal electric lifting cylinder 714 and the servo motor group 713, so that the longitudinal electric lifting cylinder 714 and the servo motor group 713 can be extended and retracted to enable the straight-line laser and the industrial camera 320 to avoid the obstacle, thereby preventing the obstacle from damaging the measuring device.

[0059] Furthermore, the obstacle detection member 712 is an ultrasonic detection group, which is arranged on the transverse mounting frame 711 located on the upper side of the conveyor belt 100, and emits ultrasonic waves to the conveyor belt 100 downward, forward and backward, respectively, and obtains the obstacle avoidance information. The ultrasonic detection group can emit ultrasonic waves and receive the emitted ultrasonic waves, generate the coordinate information of the obstacle by analyzing the received ultrasonic waves, and can also calculate and generate the obstacle avoidance information for controlling the longitudinal electric lifting and retracting cylinder 714 and the servo motor group 713 to perform corresponding obstacle avoidance and retracting actions according to the coordinate information of the obstacle.

[0060] In the above implementation process, in order to adapt to more working conditions and enable the specific point thickness acquisition device 400 to be movable, in a possible embodiment, the specific point thickness acquisition device 400 includes a displacement screw 410 and a displacement sensor 420 arranged in pairs with the conveyor belt 100 as the center, the displacement screw 410 is arranged on the placement rack, and the displacement sensor 420 is arranged at the moving end of the displacement screw 410, and the displacement screw 410 is used to drive the displacement sensor 420 to move along the width direction of the conveyor belt 100.

[0061] In the above implementation process, in order to determine the specific transverse position of the conveyor belt 100, in a possible embodiment, the transverse coordinate capture device includes an ultrasonic sensor 510 arranged on one side of the conveyor belt 100, and the ultrasonic sensor 510 is arranged on the arrangement frame 200. The ultrasonic sensor 510 is electrically connected to the control module 600, and is used to detect the position of the displacement sensor 420 and send the transverse coordinate information to the control module 600.

[0062] The present invention further provides a conveyor, comprising the conveyor belt 100 thickness measuring device as described in any one of the above items.

[0063] A method for measuring the thickness of a conveyor belt 100 in the present application can be understood by those skilled in the art through reading, and thus the method can be implemented using different devices. However, in order to make the method concrete and easy to understand, the method will be explained in conjunction with the above-mentioned conveyor belt 100 thickness measuring device. However, the method can still be implemented by other devices. Similarly, the protection scope of the method is not limited to and does not depend on the above-mentioned conveyor belt 100 thickness measuring device.

[0064] Please see Figure 6 , a method for measuring the thickness of a conveyor belt 100, comprising the following steps:

[0065] S1: Obtaining the contour information K of the conveyor belt 100: Projecting the structured light band 330 onto the upper and lower surfaces of the conveyor belt 100, respectively, taking photos of the structured light band 330 on the upper and lower surfaces of the conveyor belt 100, respectively, and performing sub-pixel processing on the photos to obtain image information, and calculating the contour information K through an image algorithm based on the image information, wherein the contour information K is a set of pixel two-dimensional coordinates of the cross section corresponding to the surface of the conveyor belt 100 covered by the structured light band 330, and the contour information K has a number of horizontal coordinate values ​​x and a number of vertical pixel values ​​y; the above-mentioned structured light band 330 can be a light band of any shape, but in this application, for the sake of convenience of explanation, a narrow and long straight light band is used as an example, and a set of pixel two-dimensional coordinates It is the coordinate of the straight narrow structured light band 330. For example, a pair of straight laser generators 310 arranged on the upper and lower sides of the conveyor belt 100 as mentioned above can project the structured light band 330 on the upper and lower sides of the same cross-section. At this time, a set of pixel two-dimensional coordinates obtained are the spatial pixel coordinates of each point along the width direction of the conveyor belt 100 on the upper and lower structured light bands 330 of the cross-section, wherein the longitudinal pixel value y is the difference obtained by subtracting the longitudinal coordinates of the same transverse coordinate value x, that is, the thickness in pix in the sub-pixel image, that is, the longitudinal pixel value y. Obviously, assuming that the cross-section is a rectangle and the coordinate information of the upper and lower lines of the rectangle is obtained, the height of the rectangle can be obtained by mathematical calculation (the height in this example is equivalent to the longitudinal pixel value y of the present application).

[0066] S2: Calculate the arithmetic information S of the conveyor belt 100: Calculate the mapping relationship t of the pixel values, and convert the contour information K into a set of arithmetic information S corresponding to the cross-section of the structured light band 330 according to the mapping relationship t, each of the arithmetic information S having a horizontal coordinate value w* and a vertical thickness value h*; this step converts the pixel unit pix of the pixel two-dimensional coordinate (horizontal coordinate value x, vertical pixel value y) into the length unit mm for subsequent calculation and understanding, that is, a set of pixel two-dimensional coordinate information (horizontal coordinate value x, vertical pixel value y) corresponds one-to-one to a set of arithmetic information S (horizontal coordinate value w*, vertical thickness value h*), which is the same set of coordinate information for the same cross-section, but the units are different.

[0067] When obtaining the arithmetic information S, a set of arithmetic information of the entire cross section can be obtained at one time. Through the one-line laser and the industrial camera 320, the photo of the entire corresponding structured light band 330 can be obtained at one time. In the control module 600, the photo can be converted into a set of pixel two-dimensional coordinates (horizontal coordinate value x, vertical pixel value y) through sub-pixel processing, image recognition and calculation, and then converted into a set of arithmetic information S through the units of the mapping relationship.

[0068] S3: Obtaining the correction information J0 of the correction point: Obtain the real thickness h of any point on the conveyor belt 100, and obtain the transverse coordinate w of the point on the conveyor belt 100 along the width direction of the conveyor belt 100. This point is the correction point; the correction point is the point position corresponding to the correction information J0 on the conveyor belt 100;

[0069] S4: Acquire arithmetic information S0 of the correction information J0: Among the set of arithmetic information S, the arithmetic information w=w* is the arithmetic information S0 of the correction point J0, and the arithmetic information S0 has a horizontal coordinate value w*0 and a vertical thickness value h*0;

[0070] The necessity of correction can be simply understood as follows: when obtaining arithmetic information S, errors will occur in the above-mentioned photo-taking, sub-pixel processing, image recognition and calculation processes. The combination of all errors will eventually lead to a large error between the arithmetic information S and the actual situation, so a set of numerical information S needs to be corrected.

[0071] During correction, first, find out the arithmetic information S0 of the correction point. Since the arithmetic information S0 of the correction point and the correction information J0 are the same data of the same point on the conveyor belt 100, and the correction information J0 is more accurate real information at the correction point on the conveyor belt, it has a more accurate real thickness h than the longitudinal thickness value h*. The real thickness h is used to correct the entire set of longitudinal thickness values ​​h*.

[0072] S5: Calculate the corrected thickness H: In one possible embodiment, the pixel difference D is calculated by the contour information K and the true thickness h, and the corrected thickness H is calculated according to the mapping relationship t and the pixel difference D. Each longitudinal thickness value h* is respectively added to the product value of the pixel difference D and the mapping relationship t to obtain a set of corrected thickness H, which is the full-section thickness information. The length units of the true thickness h and the longitudinal thickness value h*0 of the correction point are converted from mm to pixel length units pix through the mapping relationship t, wherein the longitudinal thickness value h*0 of the correction point is converted to pixel length units pix when counting, which is the longitudinal pixel value y1 of the correction point. After the true thickness h is converted into pixel units, it is counted as y0. After y1 is replaced by y0, the difference between other longitudinal pixel values ​​y and y0 in the same group of contour information K is calculated as the pixel difference D, and the pixel difference D is used to solve the corrected thickness H. The solution formula of the pixel difference D is: D=y-y0, and the solution formula of the corrected thickness H is as follows: H=h * +t*D.

[0073] In a specific implementation process, please refer to Figure 7 and Figure 8, the first step: obtaining the contour information K of the conveyor belt 100: projecting a narrow and long straight-line structured light band 330 onto the upper and lower surfaces of the conveyor belt 100 through a straight-line laser, and taking a photo of the structured light band 330 on the conveyor belt 100 through an industrial camera 320, and transmitting the photo to the control module 600, the control module 600 performs sub-pixel processing on the photo to obtain image information, specifically: firstly read a picture from the video using opencv, perform Gaussian filtering and grayscale processing on the picture, and then use the Canny algorithm to perform edge detection on the above picture, detect a white line, and perform bicubic interpolation processing on the white line to obtain a high-resolution image. The control module 600 calculates the contour information K through Canny according to the image information. The contour information K is a set of pixel two-dimensional coordinates (transverse coordinate value x, longitudinal pixel value y) of the corresponding section of the surface of the conveyor belt 100 covered by the narrow and long straight-line structured light band 330, and the unit is pix, that is, the spatial coordinates of the upper and lower contour lines of the section of the conveyor belt 100 drawn by using the structured light band 330 as a line segment. The coordinate system of the spatial coordinates takes the width direction of the conveyor belt 100 as the transverse coordinate and the thickness direction of the conveyor belt 100 as the longitudinal coordinate, so the longitudinal pixel value y is the absolute value of the difference between the longitudinal coordinate values ​​of the upper and lower contour lines of the section, and the transverse coordinate value x is the value of the transverse coordinate;

[0074] The second step is to calculate the arithmetic information S of the conveyor belt 100: Fig. 9 , calculate the mapping relationship t of the pixel value, the mapping relationship t is the conversion ratio between the pixel value on the photo after sub-pixel processing and the actual length unit in the space when the photo is taken, and through the mapping relationship t, obtain a set of arithmetic information S (horizontal coordinate value w*, vertical thickness value h*) of the corresponding cross section of the structured light band 330, and the set of arithmetic information S (horizontal coordinate value w*, vertical thickness value h*) obtained by conversion corresponds to a set of pixel two-dimensional coordinate information (horizontal coordinate value x, vertical pixel value y) one by one, which is the same set of coordinate information of the same cross section, but the units are different;

[0075] When obtaining the arithmetic information S, errors will occur in the above-mentioned photographing, sub-pixel processing, image recognition and calculation processes. All the errors combined will eventually lead to a large error between the arithmetic information S and the actual situation, so a set of numerical information S needs to be corrected, so the third step is to obtain the correction information J0 of the correction point: the real thickness h of any point on the conveyor belt 100 is obtained by the displacement sensor 420, and the transverse coordinate w of the point on the conveyor belt 100 along the width direction of the conveyor belt 100 is obtained by the ultrasonic sensor 510. This point is the correction point, and the obtained information is stored in the control module 600. The control module 600 organizes it into the correction information J0 of the correction point as (transverse coordinate w, real thickness h), and stores it for standby use;

[0076] The fourth step is to use the correction information J0 to correct the image information and the arithmetic information S: the control module 600 finds the arithmetic information S0 of the correction point from a group of arithmetic information S, and the control module 600 calculates the difference between the longitudinal pixel value of the correction point and other longitudinal pixel values ​​in the same group of contour information K, which is calculated as the pixel difference D, and is used. The arithmetic information of w=w* is the arithmetic information S0 of the correction point J0; the arithmetic information S0 of the correction point is calculated as (horizontal coordinate value w*0, longitudinal thickness value h*0).

[0077] Step 5: According to the specific calculation formula of the correction thickness H: H = h * +t*D, use the software designed by Qt to process, calculate, and fuse the collected image information and the data obtained by the sensor (lateral coordinate w) to obtain the full-section thickness information of the conveyor belt.

[0078] The method combines visual measurement technology with linear measurement technology, and utilizes the real thickness of the conveyor belt 100 in combination with the visual measurement technology. The present invention can accurately measure the full-section thickness of the conveyor belt 100, reducing parallax and measurement errors that may occur in traditional methods due to factors such as lighting. The output format is as follows: Fig.10 As shown, the actual thickness, minimum value, maximum value, average value and full-section thickness information and image information of the correction point can be included. All thickness values ​​are stored in an array form, and the thickness data obtained by analysis can be used to determine whether there is abnormal wear or damage. Based on the thickness data, the remaining service life and maintenance time of the conveyor belt 100 can be predicted.

[0079] The thickness measuring device of the conveyor belt 100 adjusts its working posture in response to the obstacle avoidance information. Therefore, when measuring the thickness of the conveyor belt 100, it can adapt to conveyor belts 100 of different widths and types, and has high flexibility and adaptability. Whether it is on a narrow or wide conveyor belt 100, this method can be effectively implemented to meet the diverse industrial application needs.

[0080] like Fig.11 As shown, the full-section thickness data of the conveyor belt 100 is displayed using a Cartesian coordinate system. When the thickness is measured using the method of the present invention, the accuracy can reach ±0.2 mm, which is much higher than the accuracy of the traditional manual measurement method. In addition, due to the use of advanced equipment and technology, the method of the present invention also has significant advantages in terms of ease of operation, degree of automation, and data processing speed.

[0081] The method provided by the present invention not only improves the accuracy of measuring the thickness of the conveyor belt 100, but also has technical effects in the following aspects:

[0082] Improve efficiency: Automated data collection and processing greatly improves measurement efficiency. The present invention does not require excessive manual intervention, can quickly complete measurement tasks, and provide real-time data feedback, which is particularly important for situations that require long-term continuous monitoring.

[0083] Optimize safety: Real-time monitoring of the thickness of the conveyor belt 100 helps prevent failure of the conveyor belt 100 due to excessive wear, thereby improving the safety of the entire conveying system;

[0084] Data tracking and analysis: The present invention makes the tracking of the conveyor belt 100 thickness data more comprehensive, facilitates historical data analysis, timely predicts and discovers potential problems, and provides data support for maintenance decisions.

[0085] In summary of the above technical effects, the present invention not only provides an efficient and accurate method for measuring the thickness of a mining conveyor belt 100 across the entire cross section, but also has strong practicability and reliability, providing powerful technical support for the maintenance and management of mining conveyor systems.

[0086] Furthermore, a pair of straight laser generators 310 are used to project a pair of straight laser beams 331 located in the same cross section onto the upper and lower surfaces of the conveyor belt 100 , respectively, and the straight laser beams 331 cover the width of the conveyor belt 100 .

[0087] Furthermore, step S2 includes the following steps:

[0088] S21: The specific steps of solving the mapping relationship t are: the computer obtains the pixel width L* of the structured light band 330 in the image information, the unit is mm, and the computer obtains the field of view width L of the structured light band 330 in the photo, the unit is pix, then the mapping relationship t is In the mapping relationship t, b is a sub-pixel processing effect coefficient, and the unit of the mapping relationship t is mm / pix;

[0089] S22: Convert the contour information K into a set of arithmetic information S according to the mapping relationship t, and the conversion formula of the horizontal coordinate value w* and the longitudinal thickness value h* of each arithmetic information S is:

[0090] Specifically, step S5 includes the following steps:

[0091] S51: Obtain the contour information K0 corresponding to the correction point: In a set of contour information K, The contour information is the contour information K0 corresponding to the correction point;

[0092] S52: Calculate the longitudinal pixel value y0 corresponding to the true thickness h according to the mapping relationship t and the true thickness h. The solution formula for the longitudinal pixel value y0 is: Replace the vertical pixel value in the contour information K0 with the vertical pixel value y0;

[0093] S53: The solution formula of the pixel difference D is: D=y-y0, the unit of the pixel difference D is pix, where y is the remaining vertical pixel values ​​in the group of contour information K where the vertical pixel value y0 is located.

[0094] Furthermore, the method further includes an adaptive obstacle avoidance step S6, wherein the adaptive obstacle avoidance step includes the following steps:

[0095] S61: Perform ultrasonic detection on the front, rear and top of the conveyor belt 100 respectively. If an obstacle is found on the conveyor belt 100, proceed to S62. Otherwise, jump to S1.

[0096] S62: Generate the obstacle avoidance signal, and the conveyor belt 100 thickness measuring device adjusts its working posture in response to the obstacle avoidance signal to avoid obstacles.

[0097] The obstacle detection component 712 is used to detect obstacles on the conveyor belt 100. If there are obstacles on the conveyor belt 100, the obstacle detection component 712 can detect the obstacles and generate obstacle avoidance information. Specifically, the obstacle detection component 712 sends the obstacle information to the control module 600, the control module 600 processes the obstacle information, generates obstacle avoidance information and sends the obstacle avoidance information to the obstacle avoidance device, the obstacle avoidance device adjusts the working posture of the image capture device in response to the obstacle avoidance information, and the obstacle avoidance device adjusts the working posture of the image capture device in response to the obstacle avoidance information, that is, the image capture device is adjusted to a working posture that can avoid the obstacle, so as to prevent the obstacle from affecting the measurement result.

[0098] It should be noted that the displacement sensor used in this application needs to be calibrated before use to obtain a more accurate true thickness h, thereby avoiding deviations in the correction results. The specific calibration method can adopt the calibration method of the displacement sensor in the prior art.

[0099] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. A conveyor belt thickness measuring device, characterized in that: It includes a layout frame arranged on both sides of the conveyor belt, and an image capture device, a specific point thickness acquisition device, a horizontal coordinate capture device and a control module arranged on the layout frame; The image capture device includes a laser generator and an industrial camera arranged in pairs with the conveyor belt as the center, the laser generator is arranged on the arrangement frame and is used to project a structured light band on the conveyor belt, and the industrial camera is used to obtain a photo of the conveyor belt with the structured light band; The specific point thickness acquisition device cooperates with the arrangement frame to move along the width direction of the conveyor belt, and the specific point thickness acquisition device is used to acquire the thickness information of the conveyor belt; The transverse coordinate capturing device is used to capture the transverse coordinate information of the specific point thickness acquiring device; The control module is electrically connected to the industrial camera, the specific point thickness acquisition device, and the horizontal coordinate capture device, and is used to process the photos, the thickness information and the horizontal coordinate information, and calculate and output the full-section thickness information.

2. The conveyor belt thickness measuring device according to claim 1, characterized in that: It also includes an obstacle avoidance device. The obstacle avoidance device includes a pair of obstacle avoidance components symmetrically arranged on the arrangement frame with the conveyor belt as the center. The obstacle avoidance component includes a transverse mounting frame, an obstacle detection component, a servo motor group and a pair of longitudinal electric telescopic cylinders. The pair of longitudinal electric telescopic cylinders are respectively arranged on the arrangement frame in the vertical direction and are respectively located on both sides of the conveyor belt. The transverse mounting frame is horizontally arranged and connected between the telescopic ends of the pair of longitudinal electric telescopic cylinders. The obstacle detection component is arranged on the transverse mounting frame. The fixed end of the servo motor group is arranged on the arrangement frame. The industrial camera is arranged on the arrangement frame through the servo motor group, and the industrial camera is arranged at the telescopic end of the servo motor group. The obstacle detection component, the servo motor group, and the pair of longitudinal electric telescopic cylinders are all electrically connected to the control module.

3. The conveyor belt thickness measuring device according to claim 1, characterized in that: The specific point thickness acquisition device includes a displacement screw and a displacement sensor arranged in pairs with the conveyor belt as the center, the displacement screw is arranged on the placement frame, the displacement sensor is arranged at the moving end of the displacement screw, and the displacement screw is used to drive the displacement sensor to move along the width direction of the conveyor belt.

4. The conveyor belt thickness measuring device according to claim 3, characterized in that: The transverse coordinate capture device includes an ultrasonic sensor arranged on one side of the conveyor belt, the ultrasonic sensor is arranged on the arrangement frame, the ultrasonic sensor is electrically connected to the control module, and is used to detect the position of the displacement sensor and send the transverse coordinate information to the control module.

5. A conveyor, characterized in that: The conveyor belt thickness measuring device comprises the device described in any one of claims 1 to 4.

6. A method for measuring the thickness of a conveyor belt, characterized in that: The following steps are involved: S1: Obtaining contour information K of the conveyor belt: projecting structured light bands onto the upper and lower surfaces of the conveyor belt respectively, taking photos of the structured light bands on the upper and lower surfaces of the conveyor belt respectively, and performing sub-pixel processing on the photos to obtain image information, and calculating the contour information K by an image algorithm based on the image information. The contour information K is a set of two-dimensional pixel coordinates of a cross section corresponding to the surface of the conveyor belt covered by the structured light band, and the contour information K has a number of transverse coordinate values ​​x and a number of longitudinal pixel values ​​y; S2: Calculate the arithmetic information S of the conveyor belt: calculate the mapping relationship t of the pixel values, and convert the contour information K into a set of arithmetic information S of the corresponding cross section of the structured light belt according to the mapping relationship t, each of the arithmetic information S has a transverse coordinate value w* and a longitudinal thickness value h*; S3: Obtaining correction information J0 of the correction point: Obtaining the true thickness h of any point on the conveyor belt, and obtaining the transverse coordinate w of the point on the conveyor belt along the width direction of the conveyor belt. This point is the correction point, and the true thickness h and the transverse coordinate w are the correction information J0; S4: Acquire arithmetic information S0 of the correction information J0: Among the set of arithmetic information S, the arithmetic information w=w* is the arithmetic information S0 of the correction point J0, and the arithmetic information S0 has a horizontal coordinate value w*0 and a vertical thickness value h*0; S5: Calculate the corrected thickness H: calculate the pixel difference D through the contour information K and the true thickness h, calculate the corrected thickness H according to the mapping relationship t and the pixel difference D, add each longitudinal thickness value h* to the product value of the pixel difference D and the mapping relationship t, and obtain a set of corrected thicknesses H, which is the full-section thickness information.

7. The method for measuring the thickness of a conveyor belt according to claim 6, characterized in that: The structured light belt is a pair of straight laser beams located in the same cross section projected onto the upper and lower surfaces of the conveyor belt, and the straight laser beams cover the entire width of the conveyor belt.

8. The method for measuring the thickness of a conveyor belt according to claim 6, characterized in that: The step S2 comprises the following steps: S21: The specific steps of solving the mapping relationship t are: the computer obtains the pixel width L* of the structured light band in the image information, the unit is mm, and the computer obtains the field of view width L of the structured light band in the photo, the unit is pix, then the mapping relationship In the mapping relationship t, b is a sub-pixel processing effect coefficient, and the unit of the mapping relationship t is mm / pix; S22: Convert the contour information K into a set of arithmetic information S according to the mapping relationship t, and the conversion formula of the horizontal coordinate value w* and the longitudinal thickness value h* of each arithmetic information S is:

9. The method for measuring the thickness of a conveyor belt according to claim 8, characterized in that: The step S5 comprises the following steps: S51: Obtain the contour information K0 corresponding to the correction point: In a set of contour information K, The contour information is the contour information K0 corresponding to the correction point; S52: Calculate the longitudinal pixel value y0 corresponding to the true thickness h according to the mapping relationship t and the true thickness h. The solution formula for the longitudinal pixel value y0 is: Replace the vertical pixel value in the contour information K0 with the vertical pixel value y0; S53: The solution formula of the pixel difference D is: D=y-y0, the unit of the pixel difference D is pix, where y is the remaining vertical pixel values ​​in the group of contour information K where the vertical pixel value y0 is located.

10. The method for measuring the thickness of a conveyor belt according to claim 1, characterized in that: The method further includes an adaptive obstacle avoidance step S6, wherein the adaptive obstacle avoidance step includes the following steps: S61: Perform ultrasonic detection on the front, rear and top of the conveyor belt respectively. If an obstacle is found on the conveyor belt, proceed to S62; otherwise, jump to S1; S62: Generate the obstacle avoidance signal, and the conveyor belt thickness measuring device adjusts its working posture in response to the obstacle avoidance signal to avoid the obstacle.

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