Material flow monitoring method and system for conveyor belt

Abstract

The present application relates to the field of transportation management technology, and the present application discloses a material flow monitoring method and system for a transport belt. The material flow monitoring method for a transport belt includes: obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, the material contour point cloud is obtained by scanning the first sensor above the belt, and the belt contour point cloud is obtained by scanning the second sensor below the belt and in the same longitudinal direction as the first sensor; obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed; determining the statistical results of the discharge flow according to the instantaneous material flow. The method of the present application can effectively improve the accuracy and reliability of material flow monitoring.

Description

Technical Field

[0001] The present application relates to the field of transportation management technology, and in particular to a material flow monitoring method and system for a transportation belt. Background Art

[0002] The accuracy of material flow monitoring on conveyor belts is crucial to industrial production. At present, belt scales are commonly used online material flow monitoring equipment, which can weigh materials more accurately. However, due to mechanical or sensor components, belt scales have strict restrictions on belt speed and range, and the equipment is difficult to repair and maintain, and cannot cope well with material flow monitoring in general scenarios.

[0003] Therefore, a number of online material flow monitoring methods based on sensor data analysis have emerged, such as visual analysis and lidar analysis. However, due to complex scenes, fast belt transportation speeds, and unclear material characteristics, it is difficult for methods based on visual analysis to accurately construct depth information and accurately count material flows. In addition, the current lidar-based material flow analysis method only focuses on the three-dimensional reconstruction of the material surface and does not realize the dynamic construction of the belt reference, that is, during transportation, the belt will deform or shift according to the load weight. This deformation is always present and changing. Calculating the cross-sectional area of ​​the material to count the material flow will produce large errors, affecting the accuracy of material flow statistics. Summary of the invention

[0004] Based on this, it is necessary to provide a material flow monitoring method and system for a conveyor belt to address the above technical problems, which can effectively improve the accuracy and reliability of material flow monitoring.

[0005] In a first aspect, a method for monitoring material flow of a conveyor belt is provided, comprising:

[0006] Obtaining a belt running speed, a material contour point cloud, and a belt contour point cloud, wherein the material contour point cloud is obtained by scanning a first sensor above the belt, and the belt contour point cloud is obtained by scanning a second sensor below the belt and in the same longitudinal direction as the first sensor;

[0007] Obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed;

[0008] According to the instantaneous material flow, the statistical result of the discharge flow is determined.

[0009] In some examples, after obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, and before obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, the method further includes:

[0010] Obtaining an affine transformation matrix between the point cloud coordinates of the material contour point cloud scanned by the first sensor and the point cloud coordinates of the belt contour point cloud scanned by the second sensor;

[0011] According to the affine transformation matrix, the material contour point cloud and the belt contour point cloud are transformed into the same coordinate system.

[0012] In some examples, obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud includes:

[0013] Obtaining the belt contour integral area according to the belt contour point cloud;

[0014] Obtaining the overall integral area of ​​the material and the belt according to the material contour point cloud;

[0015] The difference between the overall integral area of ​​the material and the belt and the integral area of ​​the belt profile is obtained, wherein the difference is the cross-sectional area of ​​the material.

[0016] In some examples, obtaining the belt contour integral area according to the belt contour point cloud includes:

[0017] According to the arrangement order of the belt contour point cloud, the belt contour point cloud is divided into M segments, wherein each segment includes N point clouds, wherein N is less than M;

[0018] Use N-order piecewise functions to fit the piecewise curve of each segment respectively;

[0019] The piecewise curves of each section are spliced ​​to obtain a belt profile distribution curve, and the belt profile distribution curve is calculated using a piecewise function integration method to obtain the belt profile integral area.

[0020] In some examples, obtaining the overall integrated area of ​​the material and the belt according to the material contour point cloud includes:

[0021] Comparing each point cloud in the material contour point cloud comprising K point clouds with the belt contour distribution curve, so as to replace the ordinate value of the point cloud below the belt contour curve with the corresponding value on the belt contour distribution curve;

[0022] After the processed material contour point cloud and the area enclosed by the abscissa axis are divided into K-1 trapezoids, the area of ​​each trapezoid is calculated, and the overall integral area of ​​the material and the belt is obtained by summing the areas of each trapezoid.

[0023] In some examples, obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed includes:

[0024] Obtaining a scan time, wherein the scan time includes a current scan time and a previous frame scan time;

[0025] According to the current scanning time, the previous frame scanning time and the belt running speed, an instantaneous material flow is obtained with the previous frame scanning time as the starting time and the current scanning time as the ending time.

[0026] In some examples, determining the statistical result of the output flow according to the instantaneous flow includes:

[0027] The instantaneous material flows whose start and end times are both within the unit time are accumulated and summed to obtain a first summation result;

[0028] For an instantaneous material flow whose starting time is less than the starting time of the unit time and whose ending time is greater than the starting time of the unit time, a first time ratio is obtained, and a first material flow rate of the instantaneous material flow in the unit time is obtained according to the first time ratio;

[0029] For an instantaneous material flow whose starting time is less than the ending time of the unit time and whose ending time is greater than the ending time of the unit time, a second time ratio is obtained, and a second material flow rate of the instantaneous material flow in the unit time is obtained according to the second time ratio;

[0030] The material flow rate per unit time is calculated based on the first summation result, the first material flow rate, and the second material flow rate.

[0031] In some examples, the method further includes: calculating the total material flow rate within a predetermined time according to the material flow rate per unit time, wherein the predetermined time is a plurality of unit times.

[0032] In some examples, before calculating the total material flow rate within a predetermined time according to the material flow rate per unit time, the method further includes:

[0033] When there is a missing material flow rate per unit time among the multiple unit times within the predetermined time, the missing material flow rate per unit time is interpolated based on the material flow rates of the adjacent unit times before and after the missing unit time.

[0034] In a second aspect, a material flow monitoring system for a conveyor belt is provided, comprising:

[0035] An acquisition module, used to obtain a belt running speed, a material contour point cloud and a belt contour point cloud, wherein the material contour point cloud is obtained by scanning a first sensor above the belt, and the belt contour point cloud is obtained by scanning a second sensor below the belt and in the same longitudinal direction as the first sensor;

[0036] An instantaneous material flow calculation module, used to obtain the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and to obtain the instantaneous material flow according to the material cross-sectional area and the belt running speed;

[0037] The monitoring module is used to determine the statistical result of the discharge flow according to the instantaneous material flow.

[0038] According to the embodiment of the present application, after obtaining the belt running speed, material contour point cloud and belt contour point cloud, the material cross-sectional area is obtained according to the material contour point cloud and the belt contour point cloud. Since the belt will deform or shift according to the load weight during the transportation of the material in the belt, the belt contour point cloud is obtained in the embodiment of the present application. The deformation of the belt can be obtained according to the belt contour point cloud, and the material cross-sectional area can be calculated based on the deformation of the belt. Thus, a more accurate material cross-sectional area can be obtained. Therefore, the instantaneous material flow obtained according to the material cross-sectional area and the belt running speed is more accurate. Furthermore, according to the instantaneous material flow, real-time and accurate monitoring of the material flow is achieved, thereby improving the accuracy and reliability of material flow monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0040] Figure 1 A flow chart of a method for monitoring material flow of a conveyor belt provided in an embodiment of the present application;

[0041] Figure 2 This is a schematic diagram of the layout of the line laser radar;

[0042] Figure 3 Schematic diagram of line lidar calibration;

[0043] Figure 4 This is a schematic diagram for calculating the cross-sectional area of ​​materials;

[0044] Figure 5 Schematic diagram of the impact of material flow statistics accuracy in different scenarios;

[0045] Figure 6 A structural block diagram of a material flow monitoring system for a conveyor belt provided in an embodiment of the present application;

[0046] Figure 7 A structural block diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The present application is further described in detail below in conjunction with the embodiments and drawings. It is to be understood that the specific embodiments described herein are only used to explain the relevant application, rather than to limit the application. It is also necessary to explain that, for ease of description, only the parts related to the application are shown in the drawings.

[0048] It should be noted that, in the absence of conflict, the embodiments of the present application, that is, the features of the embodiments, can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0049] The material flow monitoring method and system for a conveyor belt according to an embodiment of the present application are described in detail below in conjunction with the accompanying drawings.

[0050] Figure 1 FIG. 1 is a flow chart of a method for monitoring material flow of a conveyor belt according to an embodiment of the present application. Figure 1 As shown, the material flow monitoring method of the conveyor belt according to the embodiment of the present application includes the following steps:

[0051] S101: Obtaining the running speed of the transport belt (ie, belt), the material contour point cloud and the belt contour point cloud, wherein the material contour point cloud is obtained by scanning a first sensor above the belt, and the belt contour point cloud is obtained by scanning a second sensor below the belt and in the same longitudinal direction as the first sensor.

[0052] In a specific application, the belt running speed can be monitored by a pre-arranged material flow monitoring device, as well as the material contour point cloud and the belt contour point cloud can be scanned. For example: the device includes a controller such as a programmable logic controller and two sensors, wherein the two sensors are the first sensor and the second sensor in the above example. The controller is used to connect the drive motor of the belt to obtain the belt running speed in real time; the first sensor and the second sensor are used to scan the material surface point cloud (i.e., material contour point cloud) and the belt bottom surface point cloud in real time, respectively, and the belt contour point cloud is obtained based on the belt bottom surface point cloud plus the belt thickness, that is, the belt contour point cloud refers to the point cloud of the belt upper surface contour.

[0053] Generally speaking, the coordinates of the material contour point cloud scanned by the first sensor are in a coordinate system constructed with itself as the origin, and the coordinates of the belt contour point cloud scanned by the second sensor are in a coordinate system constructed with itself as the origin. Therefore, it is necessary to unify the coordinates, that is, calibrate the first sensor and the second sensor. Specifically, after obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, it includes: obtaining the affine transformation matrix between the point cloud coordinates of the material contour point cloud scanned by the first sensor and the point cloud coordinates of the belt contour point cloud scanned by the second sensor; according to the affine transformation matrix, transforming the material contour point cloud and the belt contour point cloud to the same coordinate system.

[0054] The first sensor and the second sensor take a line laser radar as an example, Figure 2 As shown in the figure, a line laser radar is arranged above the belt to scan the material contour point cloud, which is called the upper line laser radar, and the other line laser radar is arranged below the belt to scan the belt contour point cloud, which is called the lower line laser radar. Among them, the two line laser radars are arranged in the same longitudinal position. Since the coordinates of the point clouds scanned by different line laser radars are all constructed with themselves as the origin, it is necessary to perform calibration to map the point clouds scanned by different line laser radars to the same coordinate system for subsequent point cloud analysis. The calibration process of the line laser radar is as follows:

[0055] Combination Figure 3 As shown, using the online LiDAR And offline LiDAR Scan the stationary belt surface at the same time to obtain the scattered two-dimensional point clouds of the upper and lower surfaces of the belt;

[0056] Then, the edge points on both sides of the belt can be obtained by manual marking. and , and along the line segment Draw a perpendicular line to search for the farthest point as the belt midpoint, recorded as That is to say, for any line of laser radar scanning point cloud, the , and 3 points, recorded as the annotation point set The set of belt upper edge marking points is denoted as , the belt lower edge marking point set is denoted as ;

[0057] Next, Add the belt thickness to the ordinate of all point clouds in , generate a new point set, denoted as This point set That is A set of dimensioned points on the upper surface of the belt in the coordinate system.

[0058] Finally, the belt surface annotation point set is used in the coordinate system Position in and in the coordinate system Position in , calculate the affine transformation matrix The affine transformation matrix For the coordinate system To coordinate system The mapping parameters of the affine transformation matrix can be used later Complete coordinate system conversion and unification.

[0059] For example: A point in the coordinate system , using the affine transformation matrix Calculate the point at Position in coordinate system The formula is shown in Formula 1:

[0060] (1)

[0061] It should be noted that in the subsequent steps, the coordinate system is the reference coordinate, coordinate system The point clouds in the .

[0062] In the following description, line lidar The scanned point cloud of the belt's lower surface will have the belt thickness added to the ordinate. , converted into a point cloud on the belt surface.

[0063] S102: Obtain the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtain the instantaneous material flow according to the material cross-sectional area and the belt running speed.

[0064] Among them, material flow refers to the material flow on the belt.

[0065] In one embodiment of the present application, the material cross-sectional area is obtained according to the material contour point cloud and the belt contour point cloud, including: obtaining the belt contour integral area according to the belt contour point cloud; obtaining the overall integral area of ​​the material and the belt according to the material contour point cloud; obtaining the difference between the overall integral area of ​​the material and the belt and the integral area of ​​the belt contour, wherein the difference is the material cross-sectional area.

[0066] In this example, the belt contour integral area is obtained according to the belt contour point cloud, including: dividing the belt contour point cloud into M segments according to the arrangement order of the belt contour point cloud, wherein each segment includes N point clouds, wherein N is less than M; fitting the segmented curve of each segment respectively using an N-order segmented function; splicing the segmented curve of each segment to obtain the belt contour distribution curve, and calculating the belt contour distribution curve using the piecewise function integration method to obtain the belt contour integral area.

[0067] In this example, the overall integral area of ​​the material and the belt is obtained according to the material contour point cloud, including: comparing each point cloud in the material contour point cloud containing K point clouds with the belt contour distribution curve to replace the vertical coordinate value of the point cloud below the belt contour curve with the corresponding value on the belt contour distribution curve; after dividing the area enclosed by the processed material contour point cloud and the horizontal coordinate axis into K-1 trapezoids, calculating the area of ​​each trapezoid, and summing the area of ​​each trapezoid to obtain the overall integral area of ​​the material and the belt.

[0068] In one embodiment of the present application, an instantaneous material flow is obtained according to the material cross-sectional area and the belt running speed, including: obtaining a scanning time, wherein the scanning time includes a current scanning time and a previous frame scanning time; according to the current scanning time, the previous frame scanning time and the belt running speed, an instantaneous material flow with the previous frame scanning time as the starting time and the current scanning time as the ending time is obtained.

[0069] As a specific application, Figure 4 As shown, the overall integral area of ​​the material and the belt can be calculated based on the material contour point cloud Based on the belt contour point cloud, the belt contour integral area can be calculated , the difference between the two integral areas is the cross-sectional area of ​​the material The specific process is as follows:

[0070] (1) Construct the belt profile distribution curve and calculate the belt profile integral area.

[0071] Since the belt contour point cloud scanned by the offline laser radar is discrete, a large error will occur when calculating the integral area. Therefore, it is necessary to first determine the distribution curve of the belt contour to achieve high-precision belt integral area calculation. In order to reduce the fitting error of a single curve, in the embodiment of the present application, an N-order function is used to segmentally fit the belt contour distribution curve. Specifically, the belt contour point cloud containing I discrete points , divided into Each segment uses N discrete points to realize the piecewise curve of the belt profile within the interval. The representation of the piecewise function is shown in Formula 2:

[0072] (2)

[0073] in, represents the mth segment function, ; Point cloud for belt contour The single discrete point corresponding to the subscript in . The fitting method can be the least square method.

[0074] Among them, the M piecewise functions are spliced ​​together to form the belt profile distribution curve. The integral area of ​​the belt profile can be calculated using the piecewise function integration method. The calculation formula is shown in Formula 3:

[0075] (3)

[0076] in, is the integral area of ​​the belt profile, generally speaking, it is the integral area of ​​the empty belt; Indicate point The horizontal axis of Representing the belt contour point cloud The coordinates of the Nth point in .

[0077] (2) Calculate the overall integral of the belt and material.

[0078] Unlike the smooth curve of the belt profile, the material accumulation shape is random and not a smooth surface. The use of high-order curve (N>1) fitting method will increase the calculation error of the integral area. Therefore, in one embodiment of the present application, the trapezoidal method is directly used to calculate the overall integral area of ​​the belt and the material.

[0079] Specifically, firstly, the material contour point cloud containing K discrete points Each point in is compared with the belt profile distribution curve. For points below the belt profile curve, the ordinate value replaces the corresponding value on the belt profile distribution curve. The specific calculation method is shown in Formula 4:

[0080] (4)

[0081] The processed material contour point cloud The area enclosed by the horizontal axis is divided into K-1 trapezoids. The sum of the areas of each trapezoid is the overall integral area of ​​the belt and the material. The specific calculation method is shown in Formula 5:

[0082] (5)

[0083] in, is the overall integrated area of ​​the belt and material, is the area of ​​the kth trapezoid, .

[0084] To obtain the overall integral area of ​​the belt , belt profile integral area After that, the cross-sectional area of ​​the material is obtained by the difference between the two integrated areas , then, based on the cross-sectional area of ​​the material Calculate instantaneous material flow. Specifically:

[0085] Assume that the current scanning time of the online laser radar and the offline laser radar is , the previous frame scanning time is , then the instantaneous material flow The calculation method of is shown in Formula 6:

[0086] (6)

[0087] When the time interval between the online laser radar and the offline laser radar scanning is abnormal, that is, When the error occurs, an error mark is recorded and the instantaneous material flow calculation for this time period is not performed. The difference will be filled in the subsequent steps. Refers to the unit time, for example 1 second.

[0088] S103: Determine the statistical result of the discharge flow according to the instantaneous material flow.

[0089] The statistical results of the material flow include the statistical results of the material flow rate per unit time and the statistical results of the material flow rate per predetermined time, wherein the predetermined time is greater than the unit time.

[0090] In one embodiment of the present application, the calculation method of the statistical result of material flow rate per unit time includes, for example: accumulating and summing the instantaneous material flows whose start time and end time are both within the unit time to obtain a first summation result; for the instantaneous material flow whose start time is less than the start moment of the unit time and whose end time is greater than the start moment of the unit time, obtaining a first time ratio, and obtaining the first material flow rate of the instantaneous material flow within the unit time according to the first time ratio; for the instantaneous material flow whose start time is less than the end moment of the unit time and whose end time is greater than the end moment of the unit time, obtaining a second time ratio, and obtaining the second material flow rate of the instantaneous material flow within the unit time according to the second time ratio; based on the first summation result, the first material flow rate and the second material flow rate, the material flow rate per unit time is statistically calculated.

[0091] Specifically, the unit time Usually refers to the smallest unit of material flow statistics, such as If we take 1 second, the material flow per unit time is the material flow per second. Figure 5 As shown, and They are the start time and end time of a unit time period respectively.

[0092] For each unit time, its starting time It is not possible to ensure that the scanning time is completely consistent with the online laser radar (online laser radar and offline laser radar), such as Figure 5 As shown in (1), the starting time of the unit time is and end time , are all within the interval between two radar scans. Therefore, directly summing the instantaneous flow (column value) within this unit time will produce errors; in practical applications, the scanning frequency of the line laser radar is usually not completely stable, for example, Figure 5 In the case of (2), that is, the time interval between two scans fluctuates, directly summing up the traffic per unit time will produce a larger error; when the line laser radar loses frames, such as Figure 5 As shown in (3), using direct summation to count the material flow per second will produce a larger error; Figure 5 As shown in (4), the statistical error of material flow rate per unit time affects the material flow trend analysis, which usually cannot correctly display the material flow change trend.

[0093] Therefore, in one embodiment of the present application, the material flow statistics per unit time include:

[0094] The instantaneous material flow with both the start time and the end time stamp included in the unit time t is accumulated and recorded as ;

[0095] For instantaneous material flow start time , end time The instantaneous material flow is obtained according to the time ratio per unit time, which is recorded as , the calculation method is shown in Formula 7:

[0096] (7)

[0097] For instantaneous material flow start time , end time The instantaneous material flow is calculated by the time ratio, and the material flow rate per unit time is obtained, which is recorded as , the calculation method is shown in formula 8:

[0098] (8)

[0099] Will , , Add them together to get the material flow rate per unit time, recorded as .

[0100] In one embodiment of the present application, it further includes: calculating the total material flow rate within a predetermined time according to the material flow rate per unit time, wherein the predetermined time is a plurality of unit times.

[0101] It should be noted that before calculating the total material flow rate within the predetermined time based on the material flow rate per unit time, it also includes: when there is a missing material flow rate per unit time among the multiple unit times within the predetermined time, the material flow rate per unit time is interpolated based on the material flow rates of the adjacent unit times before and after the missing unit time.

[0102] Specifically, when the line laser radar has a long period of frame loss, for example, when it is running but the scanning time interval is greater than the unit time, some unit time data is lost. In this case, in the embodiment of the present application, interpolation can be used to fill in the missing data. Specifically, a specified time period containing T unit time contains T unit time material flow. , For missing data, the material flow per unit time , and its interpolation calculation method is shown in Formula 9:

[0103] (9)

[0104] in, is the most recent normal unit time flow before the missing sequence, It is the nearest normal unit time material flow after the missing sequence. After completing the interpolation, the cumulative sum can be performed to obtain a more accurate total material flow statistics.

[0105] In the prior art, when performing material flow statistics, the instantaneous material flow is directly accumulated and summed as the statistical result. However, in the actual demand for material flow statistics, in addition to counting the total material flow within a certain time period, it is also necessary to provide real-time material flow per unit time (such as per second) for analyzing the flow change trend. For material flow statistics within a unit time, direct summation will cause frequent fluctuations in the material flow per unit time, and usually cannot show the real material flow trend; for total material flow statistics, the direct accumulation and summation method usually cannot solve the accuracy loss in the case of sensor frame loss. Therefore, the embodiment of the present application solves the problem of continuous fluctuations in material flow caused by the inability to align the radar scanning frequency with the unit time based on the statistics of material flow per unit time based on the instantaneous material flow; at the same time, the total material flow statistics are determined based on the interpolation method, which solves the problem of accuracy loss of total flow statistics in the case of sensor frame loss, and effectively improves the accuracy of material flow statistics per unit time and total flow statistics.

[0106] According to the material flow monitoring method of the transport belt in the embodiment of the present application, after obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, the material cross-sectional area is obtained according to the material contour point cloud and the belt contour point cloud. Since the belt will deform or shift according to the load weight during the transportation of the material in the belt, the belt contour point cloud is obtained in the embodiment of the present application. The deformation of the belt can be obtained according to the belt contour point cloud, and the material cross-sectional area is calculated based on the deformation of the belt, thereby obtaining a more accurate material cross-sectional area. Therefore, the instantaneous material flow obtained according to the material cross-sectional area and the belt running speed is more accurate. Furthermore, according to the instantaneous material flow, real-time and accurate monitoring of the material flow is achieved, thereby improving the accuracy and reliability of material flow monitoring.

[0107] Figure 6 1 is a structural block diagram of a material flow monitoring system for a conveyor belt according to an embodiment of the present application. Figure 6 As shown, a material flow monitoring system for a conveyor belt according to an embodiment of the present application includes: an acquisition module 610, an instantaneous material flow calculation module 620 and a monitoring module 630, wherein:

[0108] An acquisition module 610 is used to obtain a belt running speed, a material contour point cloud, and a belt contour point cloud, wherein the material contour point cloud is obtained by scanning a first sensor above the belt, and the belt contour point cloud is obtained by scanning a second sensor below the belt and in the same longitudinal direction as the first sensor;

[0109] An instantaneous material flow calculation module 620 is used to obtain the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtain the instantaneous material flow according to the material cross-sectional area and the belt running speed;

[0110] The monitoring module 630 is used to determine the statistical result of the discharge flow according to the instantaneous material flow.

[0111] According to the material flow monitoring system of the transport belt in the embodiment of the present application, after obtaining the belt running speed, material contour point cloud and belt contour point cloud, the material cross-sectional area is obtained according to the material contour point cloud and the belt contour point cloud. Since the belt will deform or shift according to the load weight during the transportation of the material in the belt, the belt contour point cloud is obtained in the embodiment of the present application. The deformation of the belt can be obtained according to the belt contour point cloud, and the material cross-sectional area is calculated based on the deformation of the belt, thereby obtaining a more accurate material cross-sectional area. Therefore, the instantaneous material flow obtained according to the material cross-sectional area and the belt running speed is more accurate. Furthermore, according to the instantaneous material flow, real-time and accurate monitoring of the material flow is achieved, thereby improving the accuracy and reliability of material flow monitoring.

[0112] The specific definition of the material flow monitoring system for the conveyor belt can be found in the definition of the material flow monitoring method for the conveyor belt mentioned above, which will not be repeated here. The various modules of the above-mentioned material flow monitoring system for the conveyor belt can be implemented in whole or in part through software, hardware and their combination. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0113] In one embodiment, a computer device is provided. Figure 7 This is a block diagram of the computer device provided in the embodiment of the present application, refer to Figure 7 The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the above-mentioned material flow monitoring method embodiment of the transport belt when executing the computer program. For example, the following is performed: obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, the material contour point cloud is obtained by scanning the first sensor above the belt, and the belt contour point cloud is obtained by scanning the second sensor below the belt and in the same longitudinal direction as the first sensor;

[0114] Obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed;

[0115] According to the instantaneous material flow, the statistical result of the discharge flow is determined.

[0116] The embodiment of the present application further provides a computer-readable storage medium, the computer-readable storage medium stores a computer program, and the processor implements the above-mentioned material flow monitoring method embodiment of the transport belt when executing the computer program. For example, the following is performed: obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, the material contour point cloud is obtained by scanning the first sensor above the belt, and the belt contour point cloud is obtained by scanning the second sensor below the belt and in the same longitudinal direction as the first sensor;

[0117] Obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed;

[0118] According to the instantaneous material flow, the statistical result of the discharge flow is determined.

[0119] The present application embodiment provides a computer program product, which includes instructions. When the instructions are executed, the method described in the embodiment of the present application is executed. For example, it can be executed Figure 1The various steps of the material flow monitoring method of the transport belt shown, for example, are performed: obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, the material contour point cloud is scanned by a first sensor above the belt, and the belt contour point cloud is scanned by a second sensor below the belt and in the same longitudinal direction as the first sensor;

[0120] Obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed;

[0121] According to the instantaneous material flow, the statistical result of the discharge flow is determined.

[0122] Those of ordinary skill in the art can understand that all or part of the processes in the methods for implementing the above embodiments can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0123] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0124] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A method for monitoring material flow of a conveyor belt, characterized in that: include: Obtaining a belt running speed, a material contour point cloud, and a belt contour point cloud, wherein the material contour point cloud is obtained by scanning a first sensor above the belt, and the belt contour point cloud is obtained by scanning a second sensor below the belt and in the same longitudinal direction as the first sensor; Obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and obtaining the instantaneous material flow according to the material cross-sectional area and the belt running speed; According to the instantaneous material flow, the statistical result of the material flow is determined, including: accumulating and summing the instantaneous material flows whose start time and end time are both within the unit time to obtain a first summation result, and adding the instantaneous material flows whose start time and end time cross the start time of the unit time and the end time of the unit time to determine the target material flow rate according to the time ratio, and obtaining the material flow rate per unit time according to the first summation result and the target material flow rate.

2. The material flow monitoring method of a conveyor belt according to claim 1, characterized in that: After obtaining the belt running speed, the material contour point cloud and the belt contour point cloud, and before obtaining the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, the method further includes: Obtaining an affine transformation matrix between the point cloud coordinates of the material contour point cloud scanned by the first sensor and the point cloud coordinates of the belt contour point cloud scanned by the second sensor; According to the affine transformation matrix, the material contour point cloud and the belt contour point cloud are transformed into the same coordinate system.

3. The material flow monitoring method of a conveyor belt according to claim 1 or 2, characterized in that: The obtaining of the material cross-sectional area according to the material contour point cloud and the belt contour point cloud comprises: Obtaining the belt contour integral area according to the belt contour point cloud; Obtaining the overall integral area of ​​the material and the belt according to the material contour point cloud; The difference between the overall integral area of ​​the material and the belt and the integral area of ​​the belt profile is obtained, wherein the difference is the cross-sectional area of ​​the material.

4. The material flow monitoring method of a conveyor belt according to claim 3, characterized in that: The step of obtaining the belt contour integral area according to the belt contour point cloud comprises: According to the arrangement order of the belt contour point cloud, the belt contour point cloud is divided into M segments, wherein each segment includes N point clouds, wherein N is less than M; Use N-order piecewise functions to fit each piecewise curve separately; The piecewise curves of each section are spliced ​​to obtain a belt profile distribution curve, and the belt profile distribution curve is calculated using a piecewise function integration method to obtain the belt profile integral area.

5. The material flow monitoring method of a conveyor belt according to claim 4, characterized in that: The method of obtaining the overall integrated area of ​​the material and the belt according to the material contour point cloud comprises: Comparing each point cloud in the material contour point cloud comprising K point clouds with the belt contour distribution curve, so as to replace the ordinate value of the point cloud below the belt contour distribution curve with the corresponding value on the belt contour distribution curve; After the processed material contour point cloud and the area enclosed by the abscissa axis are divided into K-1 trapezoids, the area of ​​each trapezoid is calculated, and the overall integral area of ​​the material and the belt is obtained by summing the areas of each trapezoid.

6. The material flow monitoring method of a conveyor belt according to claim 1, characterized in that: The instantaneous material flow is obtained according to the material cross-sectional area and the belt running speed, including: Obtaining a scan time, wherein the scan time includes a current scan time and a previous frame scan time; According to the current scanning time, the previous frame scanning time and the belt running speed, an instantaneous material flow is obtained with the previous frame scanning time as the starting time and the current scanning time as the ending time.

7. The material flow monitoring method of a conveyor belt according to claim 6, characterized in that: The instantaneous material flows whose start time and end time are both within the unit time are accumulated and summed to obtain a first summation result, and the instantaneous material flows whose start time and end time cross the start time of the unit time and the end time of the unit time are determined according to the time ratio to obtain a target material flow rate, and the material flow rate per unit time is obtained according to the first summation result and the target material flow rate, including: The instantaneous material flows whose start and end times are both within the unit time are accumulated and summed to obtain a first summation result; For an instantaneous material flow whose starting time is less than the starting time of the unit time and whose ending time is greater than the starting time of the unit time, a first time ratio is obtained, and a first material flow rate of the instantaneous material flow in the unit time is obtained according to the first time ratio; For an instantaneous material flow whose starting time is less than the ending time of the unit time and whose ending time is greater than the ending time of the unit time, a second time ratio is obtained, and a second material flow rate of the instantaneous material flow in the unit time is obtained according to the second time ratio; The material flow rate per unit time is calculated based on the first summation result, the first material flow rate, and the second material flow rate.

8. The material flow monitoring method of a conveyor belt according to claim 7, characterized in that: Also includes: According to the material flow rate per unit time, the total material flow rate within a predetermined time is calculated, wherein the predetermined time is a plurality of unit times.

9. The material flow monitoring method of a conveyor belt according to claim 8, characterized in that: Before calculating the total material flow rate within a predetermined time according to the material flow rate per unit time, the method further includes: When there is a missing material flow rate per unit time among the multiple unit times within the predetermined time, the missing material flow rate per unit time is interpolated based on the material flow rates of the adjacent unit times before and after the missing unit time.

10. A material flow monitoring system for a conveyor belt, characterized in that: include: An acquisition module, used to obtain a belt running speed, a material contour point cloud and a belt contour point cloud, wherein the material contour point cloud is obtained by scanning a first sensor above the belt, and the belt contour point cloud is obtained by scanning a second sensor below the belt and in the same longitudinal direction as the first sensor; An instantaneous material flow calculation module, used to obtain the material cross-sectional area according to the material contour point cloud and the belt contour point cloud, and to obtain the instantaneous material flow according to the material cross-sectional area and the belt running speed; A monitoring module is used to determine the statistical results of the discharge flow according to the instantaneous material flow, including: accumulating and summing the instantaneous material flows whose start time and end time are both within the unit time to obtain a first summation result, and adding the instantaneous material flows whose start time and end time cross the start time of the unit time and the end time of the unit time to determine the target material flow rate according to the time ratio, and obtaining the material flow rate per unit time according to the first summation result and the target material flow rate.

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