A method for monitoring and early warning of tunnel segment transportation process

Abstract

This invention relates to the field of tunnel boring machine (TBM) segment transportation, and specifically to a method for monitoring and early warning during the transportation process. The invention acquires the overall point cloud of the transport vehicle to be unloaded, obtains the center point offset vector and deflection angle of the segment to be grasped, determines the accurate pose of the suction cup assembly, and collects the downward pressure load value in each suction cup zone in real time during the suction cup pressing process. Based on the downward pressure load value, the adsorption angle offset is analyzed to identify whether the adsorption angle of the suction cup assembly is abnormal. If abnormal, the adsorption angle of the suction cup assembly is adjusted according to the adsorption angle offset. When the adsorption angle is normal, the negative pressure rise rate of each suction cup zone is collected, and the type of segment to be grasped is considered to determine whether the negative pressure rise rate of each zone is abnormal. If no abnormality is found, the negative pressure decay rate during the movement process is collected in real time, and the adsorption anomaly degree is determined based on the type of segment to be grasped. Based on the adsorption anomaly degree, an anomaly warning is issued to ensure construction safety and transportation efficiency.

Description

Technical Field

[0001] This invention relates to the field of tunnel segment transportation, and specifically to a method for monitoring and early warning during the tunnel segment transportation process. Background Technology

[0002] In shield tunnel construction, precast concrete segments are the core components of tunnel lining. From the precast plant to the assembly inside the shield machine, they undergo multiple transportation processes, including off-site truck transfer, underground transportation, and pre-assembly segment feeding. Pre-assembly segment feeding is a critical intermediate transportation link connecting unloading and shield assembly. This link relies on vacuum suction cups to lift the segments from the transport vehicle to the segment feeder. It is a high-risk process for segment damage and suction drop failures. Therefore, it is urgent to develop a monitoring and early warning method for the shield segment transportation process.

[0003] Existing technologies, such as Chinese Patent Publication No. CN113374500B, disclose a shield tunnel segment vacuum suction cup pressure loss early warning and fall prevention system. This system uses a mass detection plate on the suction cup to detect the actual mass of the object being suctioned, and scans the contact surface between the vacuum suction cup and the object being suctioned. The analysis unit obtains the actual pore size based on the scanning results, compares the actual vacuum degree with the preset vacuum degree to determine whether there is a pressure loss, and determines the early warning time based on the pore size after confirming the pressure loss, and issues an alarm through the early warning unit.

[0004] However, the existing technology has the following problems: 1. The existing technology uses quality inspection plates to obtain overall quality data of the tube segment and uses an image scanner to detect the size of the pores on the contact surface between the suction cup and the tube segment. When the adsorption force of a certain suction cup zone decreases due to aging of the sealing ring or local defects on the surface of the tube segment, it is difficult to accurately locate the abnormal area by judging the overall quality and scanning the pores. It is impossible to locate and identify the abnormal state of the specific adsorption area, which affects the accuracy of the early warning and the efficiency of troubleshooting.

[0005] 2. Existing technologies obtain pore size through contact surface scanning, but do not take into account the effective distinction between normal pore structure characteristics and surface damage. If normal pores are misjudged as abnormal pores, it will lead to improper warning time settings, false alarms or deviations in warning levels, and affect normal construction operations. Summary of the Invention

[0006] This invention aims to address the shortcomings of existing technologies by providing a method for monitoring and early warning during the transportation of tunnel segments. It adjusts the suction cup posture using point cloud analysis, actively adjusts the suction angle based on downward load analysis, detects surface damage using the negative pressure rise rate, and calculates the degree of suction anomaly based on the negative pressure decay rate for early warning, thus achieving dynamic monitoring and early warning throughout the entire process.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The present invention provides a method for monitoring and early warning of the transportation process of tunnel segments, including: collecting the overall point cloud of the transport vehicle to be unloaded, obtaining the feature line contour of the edge of the segment to be grabbed, obtaining the center point offset vector and deflection angle of the segment to be grabbed based on the feature line contour, and determining the accurate pose of the suction cup group.

[0008] Move the suction cup assembly to the accurate position, and collect the downward load value in each suction cup zone in real time during the suction cup pressing process. Analyze the adsorption angle deviation based on the downward load value to identify whether the adsorption angle of the suction cup assembly is abnormal. If the adsorption angle is abnormal, adjust the adsorption angle of the suction cup assembly according to the adsorption angle deviation.

[0009] When the adsorption angle is normal, the negative pressure rise rate of each suction cup zone during the vacuum adsorption process is collected. Combined with the type of tube to be grasped, it is determined whether there is any abnormality in the negative pressure rise rate of each zone. If there is, it is determined that the surface of the tube is damaged, and an abnormal alarm is triggered to stop the transportation of the tube.

[0010] Conversely, during the process of controlling the suction cup group to move the tube to the feeding machine, the negative pressure attenuation rate of each suction cup zone is collected in real time. Combined with the type of tube to be grasped, the degree of adsorption abnormality is determined, and an abnormality warning is issued based on the degree of adsorption abnormality.

[0011] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention obtains the feature line contour of the edge of the segment to be grabbed by collecting the overall point cloud of the unloading transport vehicle, obtains the center point offset vector and deflection angle of the segment to be grabbed based on the feature line contour, determines the accurate pose of the suction cup group, improves the initial positioning accuracy, improves the segment grabbing and positioning efficiency, and avoids early collision damage caused by positioning errors.

[0012] (2) The present invention moves the suction cup group to the accurate position and collects the pressure load value in each suction cup zone in real time during the suction cup pressing process. Based on the pressure load value, the adsorption angle deviation is analyzed to identify whether the adsorption angle of the suction cup group is abnormal. If the adsorption angle is abnormal, the adsorption angle of the suction cup group is adjusted according to the adsorption angle deviation to ensure that the entire surface of the suction cup is uniformly attached to the surface of the tube and reduce the local overload loss of the suction cup.

[0013] (3) When the adsorption angle is normal, the present invention collects the negative pressure rise rate of each suction cup partition during the vacuum adsorption process, and determines whether there is an abnormality in the negative pressure rise rate of each partition in combination with the type of pipe segment to be grabbed. If there is, it is determined that the surface of the pipe segment is damaged, and an abnormal alarm is triggered to stop the transportation of the pipe segment. This effectively distinguishes between air leakage from the original process holes of the pipe segment and air leakage from concrete damage and cracking, thus avoiding potential quality hazards in tunnel lining.

[0014] (4) When the adsorption angle is normal, during the process of controlling the suction cup group to move the tube to the feeding machine, the negative pressure attenuation rate of each suction cup zone is collected in real time. The adsorption abnormality is determined in combination with the type of tube to be grabbed. Based on the adsorption abnormality, it is determined whether to issue an abnormal warning. The risk of the suction cup falling off the tube is predicted in real time to avoid the tube falling from the height and damaging the components, causing on-site safety accidents. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the method steps of the present invention; Figure 2 This is a schematic diagram illustrating the specific steps of the adsorption angle shift analysis method in this invention; Figure 3 This is a schematic diagram of the steps in the method for analyzing adsorption anomalies in this invention. Detailed Implementation

[0017] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. Furthermore, it should be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale.

[0018] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

[0019] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0020] Please see Figure 1 As shown, the present invention provides a method for monitoring and early warning of the tunnel segment transportation process, including: S1, collecting the overall point cloud of the transport vehicle to be unloaded, obtaining the feature line contour of the edge of the segment to be grabbed, obtaining the center point offset vector and deflection angle of the segment to be grabbed based on the feature line contour, and determining the accurate pose of the suction cup group.

[0021] Considering that transport vehicles are prone to loading and misaligning tunnel segments, and that manual calibration is insufficient to accurately determine the center and deflection angle of the segments, directly dropping the suction cups can easily result in localized suspension or single-point pressure damage to the segments. By extracting the contour from the overall point cloud and the platform baseline, and quantifying the center offset and centerline deflection angle using a coordinate system, the target pose of the suction cups can be precisely planned geometrically, reducing the risk of collisions caused by alignment errors.

[0022] The method for obtaining the center point offset vector and deflection angle includes: S11, extracting the feature lines of both ends of the pipe segment and the positioning edges of the transport vehicle support platform from the overall point cloud, and establishing a platform coordinate system based on the fixed positioning features on the support platform. In this embodiment, a rail traction vehicle is used, and the fixed positioning features of the support platform are fixed at the position of each stop and unloading.

[0023] The method for obtaining the end-face feature line contour includes: scanning the tractor support platform and the segment stack with an industrial camera to obtain overall point cloud data; filtering the collected overall point cloud to remove outliers; segmenting the pre-processed point cloud into several independent point cloud clusters based on a spatial distance clustering algorithm; identifying the point cloud clusters belonging to the main segment body; and simultaneously extracting the upper surface point cloud of the support platform from the point cloud using a plane fitting algorithm. The normal vector distribution of the segment point cloud is calculated, and the segment point cloud is divided into two opposing end-face regions and one arc region according to the normal vector direction. The two regions with opposite normal vector directions and perpendicular to the segment length direction are identified as the two end faces. Boundary point detection is performed on the point clouds of the two end-face regions respectively, extracting the point sets located at the edge of the end face, projecting them onto the plane where the end face is located, and using the least squares method to fit the arc to generate a continuous end-face feature line contour. Fitting the contour line using point cloud data is existing technology and will not be described in detail in this invention.

[0024] S12. Determine the centerline of the tunnel segment and the coordinates of its center point based on the line connecting the center points of the two end faces, and obtain the deflection angle between the centerline of the tunnel segment and the centerline of the supporting platform. The two end faces are arc-shaped and perpendicular to the direction of travel of the tractor during loading. The deflection angle refers to the angle between the centerline of the tunnel segment and the centerline of the supporting platform.

[0025] S13. Extract the design loading center point coordinates of the segment to be grabbed from the design loading center point coordinates of each segment in the shield tunnel segment transportation monitoring and early warning backend database. Obtain the center point offset vector of the segment to be grabbed based on the design loading center point coordinates. The center point coordinates refer to coordinates relative to the platform coordinate system. The center point offset vector is the vector pointing from the design loading center point coordinates to the center of the segment to be grabbed, calculated by the difference between the center coordinates of the segment to be grabbed and the design loading center point coordinates.

[0026] This invention acquires the feature line contour of the edge of the segment to be grasped by collecting the overall point cloud of the transport vehicle to be unloaded, and obtains the center point offset vector and deflection angle of the segment to be grasped based on the feature line contour. This determines the accurate pose of the suction cup group, improves the initial positioning accuracy, increases the segment grasping and positioning efficiency, and avoids early collision damage caused by positioning errors.

[0027] S2. Control the position and orientation of the suction cup assembly and analyze the deviation of the adsorption angle.

[0028] Considering that slight displacement of the support plates on both sides during transportation can cause the segments to tilt at an angle relative to their original position, if the suction cup angle pressure is not adjusted, asynchronous contact between different zones will occur, resulting in some suction cups being suspended without load or localized overload, which may lead to air leakage during vacuum pre-evacuation. Therefore, by constructing contour lines based on the load changes across all zones and the contact / non-contact boundary, the adsorption angle offset can be quantified and leveled by fixed-point rotation, ensuring uniform adhesion of the suction cup surface to the segments.

[0029] Based on this, the specific implementation steps of S2 include: S21, moving the suction cup assembly to the accurate pose. The specific implementation steps include: S211, extracting the relative position vector between the center position of the suction cup assembly and the center point of the tunnel segment from the shield tunnel segment transportation monitoring and early warning backend database, and determining the accurate position of the suction cup assembly center based on the center point offset vector. The relative position vector is obtained through the coordinate difference between the center position of the suction cup assembly and the center point of the tunnel segment, and the accurate position of the suction cup assembly center is obtained by adding the coordinates of the designed loading center point, the relative position vector, and the center point offset vector.

[0030] S212. Based on the deflection angle between the centerline of the tube segment and the centerline of the support platform, a straight line passing through the center of the suction cup group and perpendicular to the ground is used as the axis of rotation.

[0031] S213. Control the suction cup assembly to rotate in the opposite direction around the rotation axis, with the deflection angle as the rotation angle, until the centerline of the suction cup assembly is parallel to the centerline of the tube segment. This position is then taken as the accurate position. The centerline of the suction cup assembly refers to the centerline along the width direction of the suction cup assembly.

[0032] S22. During the suction cup pressing process, the pressing load value in each suction cup zone is collected in real time, and the adsorption angle offset is analyzed based on the pressing load value. For example... Figure 2 As shown, the specific implementation steps include: S221, constructing a sequence of changes in the pressure load value based on the real-time collected pressure load value in each suction cup partition, obtaining the first partition in the suction cup partition to have a non-zero pressure load value, recording the initial pressure depth of the suction cup group when the first non-zero pressure load value appears, and recording each partition with a non-zero pressure load value as a contact point.

[0033] In a specific embodiment of the present invention, the suction cup assembly includes multiple independent suction cup units and is equipped with load sensors and negative pressure sensors.

[0034] S222. Obtain the sequence of downpressure load value changes under the set downpressure increment. When the downpressure load value sequence for any partition is zero, determine each contour line based on the current downpressure load value of each partition. In a specific embodiment of the present invention, the downpressure increment is set to 50% of the design standard downpressure increment. For example, in this embodiment, the design standard downpressure increment is 20mm, so the downpressure increment is set to 10mm, that is, obtain the downpressure load value sequence between 0 and 10mm. The acquisition time frequency of the sequence is set to 0.1s.

[0035] S223. The contour line with the smallest downward load value is designated as the minimum contour line, and the contour line with the largest downward load value is designated as the maximum contour line.

[0036] S224. Calculate the difference in downward pressure load between the minimum and maximum contour lines, as well as the distance between the minimum and maximum contour lines, and comprehensively calculate the adsorption angle offset. The formula for calculating the adsorption angle offset is as follows: .

[0037] in Represents the adsorption angle offset. This represents the difference in downward load values. is the suction cup stiffness coefficient, where This represents the increase in downward load value per unit downward pressure distance of the suction cup assembly. This is an inherent property of the suction cup and can be calibrated in advance through experiments. This represents the distance between the minimum and maximum contour lines.

[0038] S225. When the sequence of downward pressure load values ​​for a certain partition is all zero, a dividing line is determined based on that partition, and the adsorption angle offset is determined in combination with the set downward pressure increment. The specific implementation steps include: S2251. Each partition where the sequence of downward pressure load values ​​is all zero is recorded as a non-contact point, and the geometric boundary line between the non-contact point and the contact point is obtained and recorded as the dividing line.

[0039] S2252. Measure the vertical distance from the dividing line to the first contact point with a non-zero downward pressure load value, calculate the ratio of the set downward pressure increment to the vertical distance, and record the arctangent of the ratio as the adsorption angle offset.

[0040] S23. Identify whether the suction cup assembly's adsorption angle is abnormal. If the adsorption angle is abnormal, adjust the suction cup assembly's adsorption angle according to the adsorption angle offset. The specific implementation steps include: S231. When the sequence of downward load values ​​without any partitions is all zero, the horizontal line passing through the geometric center of the contour line with the largest downward load value is recorded as the axis of rotation.

[0041] S232. When the sequence of downward load values ​​for a certain partition is all zero, obtain the contour lines of the suction cup assembly surface and the dividing line, and denote the contour line with the largest downward load value as the axis of rotation.

[0042] S233. Fix the rotating axis and control the suction cup assembly to rotate around the rotating axis with the suction angle offset as the rotation angle in the direction close to the tube sheet.

[0043] This invention moves the suction cup assembly to an accurate position and collects the downward load value in each suction cup zone in real time during the suction cup pressing process. Based on the downward load value, it analyzes the adsorption angle deviation and identifies whether the adsorption angle of the suction cup assembly is abnormal. If the adsorption angle is abnormal, it adjusts the adsorption angle of the suction cup assembly according to the adsorption angle deviation to ensure that the suction cup is uniformly attached to the surface of the tube and reduces the local overload loss of the suction cup.

[0044] S3. Determine if there is any abnormality in the negative pressure rise rate of each zone. If so, issue an abnormality alarm and stop the transportation of the tunnel segments.

[0045] Considering the prefabrication process of tunnel segments inherently includes fixed-position process holes, air leakage at these locations is normal. Treating all leaks as negative pressure anomalies would lead to frequent false shutdowns. It is necessary to analyze the hole distribution based on the segment model, compare the negative pressure rise rate by region, and for holes with abnormal rates, refer to the normal values ​​for the same area. For non-hole areas, exceeding the rate standard directly indicates a leak due to damage. This precise differentiation between native leaks and cracks in the tunnel segment itself avoids false alarms or missed damage detection.

[0046] Based on this, the specific implementation steps of S3 include: S31, when the adsorption angle is normal, collect the negative pressure rise rate of each suction cup zone during the vacuum adsorption process, and determine whether there is any abnormality in the negative pressure rise rate of each zone in combination with the type of tunnel segment to be grasped. The specific implementation steps are as follows: S311, based on the type of tunnel segment to be grasped, determine the distribution location of special holes of the tunnel segment to be grasped from the special hole distribution location of each type of tunnel segment in the shield tunnel segment transportation monitoring and early warning background database.

[0047] S312. Obtain the average and standard deviation of the negative pressure rise rate for each zone, and set the normal range of negative pressure based on the average and standard deviation. Specifically, the sum of the average and three times the standard deviation is recorded as the maximum value of the normal range of negative pressure, and the difference between the average and three times the standard deviation is recorded as the minimum value of the normal range of negative pressure.

[0048] S313. If the negative pressure rise rate of a certain zone is not within the normal range, it is recorded as a suspected abnormal zone. If a suspected abnormal zone is located in a special hole distribution location, the mode of the negative pressure rise rate of all zones located in the same special hole distribution location is obtained and recorded as the representative negative pressure rise rate.

[0049] S314. If the deviation between the negative pressure rise rate of the suspected abnormal area and the representative negative pressure rise rate exceeds a set deviation range, then the negative pressure rise rate of the suspected abnormal area is determined to be abnormal. In this embodiment, the set deviation range is set to 1% of the representative negative pressure rise rate, but the implementer can also set other specific values ​​according to the actual situation.

[0050] S315. If a suspected abnormal area is not located in a special hole distribution location, then the negative pressure rise rate of the suspected abnormal area is determined to be abnormal.

[0051] S32. If the condition is found to be damaged, the surface of the tunnel segment is determined to be damaged, an abnormal alarm is triggered, and the transportation of the tunnel segment is stopped.

[0052] Specifically, if the currently adsorbed segment is located at the bottom of the segment stack on the transport vehicle, the suction cup group is released directly to release the adsorption, and the segment remains on the support platform; if it is located at the top of the segment stack, the suction cup group is controlled to move the currently adsorbed segment away from the stack and place it in the nearby idle area of ​​the tractor, so as to continue adsorbing and transporting the segments below.

[0053] When the adsorption angle is normal, this invention collects the negative pressure rise rate of each suction cup zone during the vacuum adsorption process, and determines whether there is an abnormality in the negative pressure rise rate of each zone in combination with the type of pipe segment to be grasped. If there is, it is determined that the surface of the pipe segment is damaged, and an abnormal alarm is triggered to stop the transportation of the pipe segment. This effectively distinguishes between air leakage from the original process holes of the pipe segment and air leakage from concrete damage and cracking, thus avoiding potential quality hazards in tunnel lining.

[0054] S4. When the adsorption angle is normal, determine the degree of adsorption abnormality during the process of moving to the tablet feeder, and determine whether to issue an abnormality warning.

[0055] Considering that the negative pressure will decrease slightly during the transfer of the segments from the tractor to the feeder, different attenuation rates reflect adsorption anomalies. Higher attenuation rates result in more anomalies and significantly different risks of segment fall. Furthermore, considering that the attenuation rate at the hole location will be higher than in other areas, it is necessary to combine the hole location with the elimination of normal attenuation. The degree of adsorption anomaly should be quantified by comprehensively considering the attenuation deviation and the spatial center of gravity of the anomaly area. After normalization and grading, early warnings should be triggered as needed. This will reduce unnecessary alarms and allow for early prediction of segment fall risks.

[0056] Based on this, the specific implementation steps of S4 include: S41, Conversely, during the process of controlling the suction cup group to move the tube sheet to the feeding machine, the negative pressure attenuation rate of each suction cup zone is collected in real time, and the adsorption anomaly degree is determined in combination with the type of tube sheet to be grasped. For example... Figure 3 As shown, the specific implementation steps include: S411, determining a preset attenuation tolerance band based on the negative pressure attenuation rate of each suction cup partition under historical normal operating conditions; determining an initial abnormal zone based on the negative pressure attenuation rate of each suction cup partition and the preset attenuation tolerance band; and determining the actual negative pressure attenuation abnormal zone in conjunction with the distribution location of special holes. The method for determining the actual negative pressure attenuation abnormal zone includes: S4111, if an initial abnormal zone is located at the distribution location of special holes, obtaining the negative pressure attenuation rate of the same special holes in history to determine the upper limit of the normal negative pressure attenuation rate of the corresponding special holes. The method for obtaining the preset attenuation tolerance band includes: obtaining the negative pressure attenuation rate of each suction cup partition under historical normal operating conditions, calculating its average value and standard deviation, recording the sum of the average value and three times the standard deviation as the upper limit of the preset attenuation tolerance band, and recording the difference between the average value and three times the standard deviation as the lower limit of the preset attenuation tolerance band, thus obtaining the preset attenuation tolerance band.

[0057] Specifically, in a specific embodiment of the present invention, the method for obtaining the upper limit of the normal negative pressure attenuation rate is as follows: obtain the third quartile and the first quartile of the negative pressure attenuation rate of the same special holes in history, obtain the difference between the third quartile and the first quartile, record it as the quantile distance, record the sum of 1.5 times the quantile distance and the third quartile as the outlier boundary value, remove all negative pressure attenuation rates greater than the outlier boundary value, and take the maximum value of the remaining negative pressure attenuation rate as the upper limit of the normal negative pressure attenuation rate of the corresponding special hole.

[0058] S4112. If the negative pressure attenuation rate of the initial abnormal zone is greater than the upper limit of the normal negative pressure attenuation rate, then the initial abnormal zone is determined to be an actual negative pressure attenuation abnormal zone; otherwise, the initial abnormal zone is determined to be normal.

[0059] S4113. If the initial abnormal zone is not located at the location of the special hole distribution, it shall be recorded as the actual negative pressure attenuation abnormal zone.

[0060] S412. Obtain the average attenuation rate of all normal zones except for the actual negative pressure attenuation abnormal zone. Record the ratio of the negative pressure attenuation rate of each actual negative pressure attenuation abnormal zone to the average attenuation rate as the attenuation deviation factor of each zone.

[0061] S413. Obtain the centroid position of the spatial distribution of all actual negative pressure attenuation abnormal zones, and record the distance between the centroid position and the center point of the tube segment as the adsorption centroid deviation distance.

[0062] S414. The adsorption anomaly degree is obtained by comprehensively calculating the sum of the attenuation deviation factors of each region and the centroid deviation distance.

[0063] In a specific embodiment of the present invention, the formula for calculating the adsorption anomaly is as follows: .

[0064] in This is the sum of the attenuation deviation factors for each region. To absorb the distance of the center of gravity deviation, The length of the tube segment is given by the formula. A larger attenuation deviation factor results in more attenuation zones, a longer deviation distance from the adsorption center of gravity, and a higher degree of adsorption anomaly. To avoid the adsorption anomaly degree being non-zero when the adsorption centroid deviation distance is 0, the product calculation is used to reflect the coupled amplification effect of the adsorption centroid deviation distance and the attenuation deviation factor on the adsorption risk.

[0065] S42. Determine whether to issue an anomaly warning based on the adsorption anomaly degree. The specific implementation steps are as follows: S421. Obtain the adsorption anomaly degree of each historical abnormal transport, and record the minimum adsorption anomaly degree as the representative adsorption anomaly degree.

[0066] S422. If the adsorption anomaly is greater than the representative adsorption anomaly, then the set adsorption anomaly is used as the normalized adsorption anomaly; otherwise, the ratio of the adsorption anomaly to the representative adsorption anomaly is used to calculate the normalized adsorption anomaly. The set adsorption anomaly is 1.

[0067] S423. Determine the severity level of the anomaly based on the normalized adsorption anomaly degree, and determine whether to issue an anomaly warning based on the severity level. In a specific embodiment of the present invention, when the normalized adsorption anomaly is [0, 0.5), the severity level is recorded as low; when the normalized adsorption anomaly is [0.5, 0.8), the severity level is recorded as medium; and when the normalized adsorption anomaly is [0.8, 1], the severity level is recorded as high. When the severity level is recorded as medium or higher, a corresponding warning is issued.

[0068] When the adsorption angle is normal, during the process of controlling the suction cup group to move the tube to the feeding machine, the negative pressure attenuation rate of each suction cup zone is collected in real time. Combined with the type of tube to be grabbed, the degree of adsorption abnormality is determined. Based on the degree of adsorption abnormality, it is determined whether to issue an abnormal warning, and the risk of the suction cup falling off the tube is predicted in real time to avoid the tube falling from a height and damaging the components, causing on-site safety accidents.

[0069] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0070] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0071] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0072] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0073] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for monitoring and early warning during the transportation of tunnel segments, characterized in that, include: Collect the overall point cloud of the transport vehicle to be unloaded, obtain the feature line contour of the edge of the segment to be grabbed, obtain the center point offset vector and deflection angle of the segment to be grabbed based on the feature line contour, and determine the accurate pose of the suction cup group. Move the suction cup assembly to the accurate position, collect the downward load value in each suction cup zone in real time during the suction cup pressing process, analyze the adsorption angle deviation based on the downward load value, identify whether the adsorption angle of the suction cup assembly is abnormal, and if the adsorption angle is abnormal, adjust the adsorption angle of the suction cup assembly according to the adsorption angle deviation. When the adsorption angle is normal, the negative pressure rise rate of each suction cup zone during the vacuum adsorption process is collected. Combined with the type of tube to be grasped, it is determined whether there is an abnormality in the negative pressure rise rate of each zone. If there is, it is determined that the surface of the tube is damaged, and an abnormal alarm is triggered to stop the transportation of the tube. Conversely, during the process of controlling the suction cup group to move the tube to the feeding machine, the negative pressure attenuation rate of each suction cup zone is collected in real time, and the adsorption anomaly is determined in combination with the type of tube to be grasped. Based on the adsorption anomaly, it is determined whether to issue an anomaly warning. The analysis method for the adsorption angle shift includes: Based on the real-time collected downward load values ​​in each suction cup partition, a sequence of downward load value changes is constructed. The first partition in the suction cup partition to show a non-zero downward load value is obtained, and the initial downward depth of the suction cup group when the first non-zero downward load value appears is recorded. Each partition with a non-zero downward load value is recorded as a contact point. Obtain the sequence of download value changes under the set download increment. When there are no download value sequences for any partition that are all zero, determine each contour line based on the current download value of each partition. The contour line with the smallest downward load value is designated as the minimum contour line, and the contour line with the largest downward load value is designated as the maximum contour line. Calculate the difference in downward load between the minimum and maximum contour lines, as well as the distance between the minimum and maximum contour lines, and comprehensively calculate the adsorption angle offset. When the sequence of downward load values ​​for a certain partition is all zero, the dividing line is determined based on that partition, and the adsorption angle offset is determined by setting the downward load increment. The methods for determining whether there are abnormalities in the negative pressure rise rate of each zone include: Based on the type of tunnel segment to be captured, the distribution location of special holes in the tunnel segment to be captured is determined from the distribution location of special holes in each type of tunnel segment in the shield tunnel segment transportation monitoring and early warning backend database. Obtain the average and standard deviation of the negative pressure rise rate for each zone, and set the normal range of negative pressure based on the average and standard deviation; If the negative pressure rise rate of a certain zone is outside the normal range, it is recorded as a suspected abnormal zone. If a suspected abnormal zone is located in a special hole distribution location, the mode of the negative pressure rise rate of all zones located in the same special hole distribution location is obtained and recorded as the representative negative pressure rise rate. If the negative pressure rise rate of the suspected abnormal area deviates from the negative pressure rise rate representative of the negative pressure rise rate by more than the set deviation range, then the negative pressure rise rate of the suspected abnormal area is determined to be abnormal. If a suspected abnormal area is not located in a specific hole distribution area, then the negative pressure rise rate of the suspected abnormal area is determined to be abnormal.

2. The method for monitoring and early warning of shield tunnel segment transportation process according to claim 1, characterized in that, The methods for obtaining the center point offset vector and deflection angle include: Feature lines on both ends of the pipe segment and positioning edges of the transport vehicle support platform are extracted from the overall point cloud. Based on the fixed positioning features on the support platform, a platform coordinate system is established. The centerline of the segment and the coordinates of the center point are determined by connecting the center points of the two end faces, and the deflection angle between the centerline of the segment and the centerline of the supporting platform is obtained. The design loading center coordinates of the segment to be captured are extracted from the design loading center coordinates of each segment in the shield tunnel segment transportation monitoring and early warning backend database. The center point offset vector of the segment to be captured is obtained based on the design loading center coordinates.

3. The method for monitoring and early warning of shield tunnel segment transportation process according to claim 2, characterized in that, The specific method for moving the suction cup assembly to the accurate pose includes: Extract the relative position vector between the center position of the suction cup group and the center point of the tunnel segment from the shield tunnel segment transportation monitoring and early warning backend database, and determine the accurate position of the center of the suction cup group based on the center point offset vector; Based on the deflection angle between the centerline of the tunnel segment and the centerline of the support platform, a straight line passing through the center of the suction cup group and perpendicular to the ground is taken as the axis of rotation. Control the suction cup assembly to rotate around the rotation axis, with the deflection angle as the rotation angle, until the center line of the suction cup assembly is parallel to the center line of the tube segment, and take the pose at this time as the accurate pose.

4. The method for monitoring and early warning of shield tunnel segment transportation process according to claim 1, characterized in that, The method for determining the adsorption angle offset by combining the dividing line when the sequence of downward load values ​​in a certain partition is all zero: Each partition where the sequence of downward load values ​​is all zero is recorded as a non-contact point. The geometric boundary between the non-contact point and the contact point is obtained and recorded as the dividing line. Measure the vertical distance from the dividing line to the first contact point where a non-zero downward pressure load value appears, calculate the ratio of the set downward pressure increment to the vertical distance, and record the arctangent of the ratio as the adsorption angle offset.

5. The method for monitoring and early warning of shield tunnel segment transportation process according to claim 1, characterized in that, The specific method for adjusting the adsorption angle of the suction cup assembly based on the adsorption angle offset includes: When the sequence of download values ​​without any partitions is all zero, the horizontal line passing through the geometric center of the contour line with the largest download value is denoted as the axis of rotation; When the sequence of downward load values ​​for a certain partition is all zero, obtain the contour lines of the suction cup assembly surface and the dividing line, and record the contour line with the largest downward load value as the axis of rotation. A fixed rotating axis is used to control the suction cup assembly to rotate around the rotating axis with the suction angle offset as the rotation angle, in the direction of getting closer to the tube sheet.

6. The method for monitoring and early warning of shield tunnel segment transportation process according to claim 1, characterized in that, The method for determining the adsorption anomaly degree includes: The preset attenuation tolerance zone is determined based on the negative pressure attenuation rate of each suction cup partition under historical normal working conditions. The initial abnormal zone is determined based on the negative pressure attenuation rate of each suction cup partition and the preset attenuation tolerance zone. The actual negative pressure attenuation abnormal zone is determined by combining the distribution location of special holes. Obtain the average attenuation rate of all normal zones except for the actual negative pressure attenuation abnormal zone, and record the ratio of the negative pressure attenuation rate of each actual negative pressure attenuation abnormal zone to the average attenuation rate as the attenuation deviation factor of each zone. Obtain the centroid position of the spatial distribution of all actual negative pressure attenuation abnormal zones, and record the distance between the centroid position and the center point of the tube segment as the adsorption centroid deviation distance; The adsorption anomaly is calculated by combining the sum of the attenuation deviation factors of each region with the centroid deviation distance.

7. A method for monitoring and early warning during the transportation of tunnel segments according to claim 6, characterized in that, The method for determining the actual negative pressure attenuation anomaly zone includes: If an initial abnormal area is located in a special hole distribution area, the negative pressure attenuation rate of the same special hole in history is obtained to determine the upper limit of the normal negative pressure attenuation rate of the corresponding special hole. If the negative pressure attenuation rate of the initial abnormal zone is greater than the upper limit of the normal negative pressure attenuation rate, then the initial abnormal zone is determined to be an actual negative pressure attenuation abnormal zone; otherwise, the initial abnormal zone is determined to be normal. If the initial abnormal zone is not located in the specific hole distribution area, it is recorded as the actual negative pressure attenuation abnormal zone.

8. The method for monitoring and early warning of shield tunnel segment transportation process according to claim 1, characterized in that, The specific methods for determining whether to issue an anomaly warning include: Obtain the adsorption anomaly degree of each historical abnormal transport, and record the minimum adsorption anomaly degree as the representative adsorption anomaly degree. If the adsorption anomaly is greater than the representative adsorption anomaly, the set adsorption anomaly is used as the normalized adsorption anomaly; otherwise, the ratio of the adsorption anomaly to the representative adsorption anomaly is used to calculate the normalized adsorption anomaly. The severity level of the anomaly is determined based on the normalized adsorption anomaly degree, and whether to conduct anomaly prevention is determined based on the severity level of the anomaly.

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