Mortar crack spatial form identification method based on three-dimensional scanning

Abstract

The invention relates to the technical field of form recognition, in particular to a mortar crack spatial form recognition method based on three-dimensional scanning, which comprises the following steps: acquiring initial frame three-dimensional scanning data, and constructing an initial crack point cloud model based on the initial frame three-dimensional scanning data; dynamically updating the initial fracture point cloud model based on the current frame of three-dimensional scanning data to obtain an updated fracture point cloud model; based on the updated fracture point cloud model, extracting fracture edge feature points; according to the fracture edge feature points, constructing a fracture edge feature curve; carrying out regional division on the fracture by utilizing the fracture edge characteristic curve to obtain a plurality of fracture sub-regions; and each fracture sub-region has relatively independent morphological characteristics. According to the method, the initial crack point cloud model is dynamically updated, so that the change condition of the crack can be monitored in real time, the newly added crack and the disappearing crack can be effectively identified, the timeliness and the accuracy of detection are improved due to the dynamic nature, and the actual state of the mortar structure can be better reflected.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of morphological identification, in particular to a mortar crack spatial morphology identification method based on three-dimensional scanning. BACKGROUND

[0002] At present, traditional methods often rely on manual inspection and measurement, which not only consumes time, but also is susceptible to human factors such as the experience level and judgment ability of the operator, leading to inconsistency of the results; moreover, real-time monitoring cannot be provided, and inspection usually needs to be performed within a specific time period, so that changes in the cracks cannot be captured in a timely manner, which may lead to a lag in response to structural safety hazards.

[0003] In addition, traditional methods are often cumbersome in data processing and analysis, involving a large amount of manual calculation and drawing analysis, which is inefficient and prone to errors, and the lack of automated tools makes the data analysis process even more complex; moreover, three-dimensional spatial information of the cracks cannot be comprehensively obtained, and more reliance is placed on two-dimensional images or simple measurements, which leads to insufficient understanding of the morphology of the cracks and inability to comprehensively evaluate the impact. SUMMARY

[0004] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a mortar crack spatial morphology identification method based on three-dimensional scanning, comprising:

[0005] Obtaining initial frame three-dimensional scanning data, and constructing an initial crack point cloud model based on the initial frame three-dimensional scanning data; wherein the initial crack point cloud model includes spatial point distribution information of the mortar cracks in the initial state;

[0006] Based on the current frame three-dimensional scanning data, the initial crack point cloud model is dynamically updated to obtain an updated crack point cloud model; wherein the updating process includes identification and addition of new crack points and marking and removal of disappeared crack points;

[0007] Based on the updated crack point cloud model, crack edge feature points are extracted; wherein the crack edge feature points are used to define the boundary profile of the cracks;

[0008] According to the crack edge feature points, a crack edge feature curve is constructed; wherein the crack edge feature curve is used to represent the strike and morphological changes of the cracks; the crack edge feature curve is used to divide the cracks into multiple crack sub-regions; each crack sub-region has relatively independent morphological characteristics;

[0009] For each crack sub-region, the spatial morphology parameters of the crack sub-region are analyzed; wherein the spatial morphology parameters include the length, width, depth and curvature of the crack sub-region;

[0010] Based on the spatial form parameters of each fissure sub-region, the spatial form of the fissures of the mortar is comprehensively evaluated to obtain a comprehensive evaluation result of the spatial form of the fissures of the mortar.

[0011] Preferably, based on the three-dimensional scanning data of the current frame, the initial fissure point cloud model is dynamically updated to obtain an updated fissure point cloud model, including:

[0012] The three-dimensional scanning data of the current frame is spatially matched with the initial fissure point cloud model to determine overlapping regions and non-overlapping regions;

[0013] In the non-overlapping regions, new fissure points are identified and added to the initial fissure point cloud model;

[0014] In the overlapping regions, by comparing the position information of the corresponding points of the three-dimensional scanning data of the current frame and the initial fissure point cloud model, the disappearing fissure points are marked;

[0015] The marked disappearing fissure points are removed from the initial fissure point cloud model to obtain the updated fissure point cloud model.

[0016] Preferably, based on the updated fissure point cloud model, fissure edge feature points are extracted, including:

[0017] The updated fissure point cloud model is subjected to neighborhood analysis to determine the neighborhood point set within a predetermined range around each point;

[0018] The distance variation rate of each point and its neighborhood point set in each direction is calculated;

[0019] Points with a distance variation rate exceeding a predetermined threshold are selected as fissure edge feature points.

[0020] Preferably, based on the fissure edge feature points, a fissure edge feature curve is constructed, including:

[0021] The fissure edge feature points are sorted based on their order along the fissure direction;

[0022] A curve fitting algorithm is used to fit the sorted fissure edge feature points into a continuous fissure edge feature curve.

[0023] Preferably, the fissure edge feature curve is used to divide the fissure into multiple fissure sub-regions, including:

[0024] Curvature mutation points are found on the fissure edge feature curve; wherein the curvature mutation points represent positions where the fissure form changes;

[0025] The fissure edge feature curve is divided into multiple curve segments using the curvature mutation points as segmentation points;

[0026] The area enclosed by each curve segment is a crack sub-region.

[0027] Preferably, for each fracture sub-region, the spatial morphological parameters of the fracture sub-region are analyzed, including:

[0028] The length of the fracture sub-region is obtained by calculating the spatial distance between the first and last points on the edge feature curve of the fracture sub-region.

[0029] For the width of the crack sub-region, the distance between the characteristic curves of the crack edge is measured at multiple locations in the direction perpendicular to its length, and the average value is taken as the width value;

[0030] The depth of the fracture sub-region is determined by comparing the vertical distance between the bottom point and the top point of the fracture sub-region;

[0031] The curvature of the fracture sub-region is obtained by comprehensive analysis based on the curvature values ​​of each point on the characteristic curve of the fracture edge.

[0032] Preferably, based on the spatial morphological parameters of each fracture sub-region, a comprehensive evaluation of the spatial morphology of mortar fractures is conducted, including:

[0033] Weight values ​​are set for different spatial morphology parameters; wherein, the weight values ​​are determined according to the importance of each spatial morphology parameter to the fracture morphology;

[0034] The spatial morphological parameters of each fracture sub-region are weighted and summed according to their corresponding weight values ​​to obtain the morphological evaluation value of each fracture sub-region.

[0035] A comprehensive analysis of the morphological evaluation values ​​of all fracture sub-regions was conducted, and the interrelationships between fracture sub-regions were combined to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures.

[0036] Preferably, a comprehensive analysis of the morphological evaluation values ​​of all fracture sub-regions is performed, and the interrelationships between fracture sub-regions are combined to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures, including:

[0037] Analyze the connection relationships between fracture sub-regions. If multiple fracture sub-regions are interconnected, treat the fracture sub-regions as a whole fracture group.

[0038] For the overall fracture group, the morphological evaluation values ​​of the fracture sub-regions included in the overall fracture group are integrated. The integration method is to take the average value or to perform a weighted average based on the importance of the fracture sub-regions in the whole.

[0039] Based on the integrated results of the overall fracture group and the morphological evaluation values ​​of individual fracture sub-regions, combined with the distribution of fractures in the mortar, a comprehensive evaluation result of the spatial morphology of mortar fractures is obtained.

[0040] Preferably, after comprehensively evaluating the spatial morphology of mortar fractures based on the spatial morphological parameters of each fracture sub-region to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures, the method further includes:

[0041] During the identification process, if an abnormal change in the crack morphology is detected, a retrospective analysis is performed on the three-dimensional scan data from the initial frame to the current frame.

[0042] By retrospectively analyzing to determine the starting frame of the abnormal change in fracture morphology, the three-dimensional scan data from the starting frame to the current frame are reprocessed. The reprocessing process includes reconstructing the fracture point cloud model, extracting fracture edge feature points, constructing fracture edge feature curves, dividing the fracture into sub-regions, and analyzing spatial morphological parameters.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] (1) By dynamically updating the initial crack point cloud model, the present invention can monitor the changes in cracks in real time and effectively identify newly added cracks and disappearing cracks. This dynamism improves the timeliness and accuracy of detection and can better reflect the actual state of the mortar structure. Moreover, by using neighborhood analysis and distance change rate calculation, crack edge feature points can be accurately extracted. This process reduces human intervention, improves the degree of automation, and thus improves work efficiency.

[0045] (2) This invention provides comprehensive data support for the characteristic description of cracks by constructing characteristic curves of crack edges and analyzing their spatial morphological parameters such as length, width, depth and curvature. This analysis can help engineers to deeply understand the geometric morphology of cracks and their evolution law. Moreover, based on the weighted summation of the spatial morphological parameters of each crack sub-region, the resulting morphological evaluation value can not only provide an evaluation of a single crack, but also combine the relationship between cracks to comprehensively evaluate the health status of the entire mortar structure. This provides a scientific basis for subsequent maintenance and repair decisions. Attached Figure Description

[0046] Figure 1 This is a schematic flowchart of the overall method in one embodiment of the present invention. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] Example 1, please refer toFigure 1 This invention provides a technical solution: a method for identifying the spatial morphology of mortar cracks based on three-dimensional scanning, comprising:

[0049] S1. Obtain the initial frame 3D scan data and construct an initial crack point cloud model based on the initial frame 3D scan data; wherein, the initial crack point cloud model includes the spatial point distribution information of mortar cracks in the initial state;

[0050] S2. Based on the current frame's 3D scan data, dynamically update the initial fracture point cloud model to obtain the updated fracture point cloud model; the update process includes identifying and adding new fracture points and marking and removing disappearing fracture points.

[0051] S3. Based on the updated crack point cloud model, extract crack edge feature points; where crack edge feature points are used to define the boundary contour of the crack.

[0052] S4. Based on the characteristic points at the fracture edge, construct the fracture edge characteristic curve; the fracture edge characteristic curve is used to characterize the fracture's orientation and morphological changes; using the fracture edge characteristic curve, divide the fracture into regions to obtain multiple fracture sub-regions; each fracture sub-region has relatively independent morphological characteristics.

[0053] S5. For each fracture sub-region, analyze the spatial morphological parameters of the fracture sub-region; the spatial morphological parameters include the length, width, depth and curvature of the fracture sub-region.

[0054] S6. Based on the spatial morphological parameters of each fracture sub-region, a comprehensive evaluation of the spatial morphology of mortar fractures is conducted to obtain the comprehensive evaluation results of the spatial morphology of mortar fractures.

[0055] It should be noted that 3D scanning instruments (such as laser scanners or structured light scanners) are used to acquire 3D data of the initial frame. Through scanning, a spatial point cloud model of the mortar surface and its cracks can be obtained, recording the morphology and distribution of the cracks in the initial state. For example, suppose a concrete wall is being inspected. The data obtained after scanning with a laser scanner forms a 3D point cloud model containing crack information. This model shows the location and shape of all cracks on the wall surface in the initial state.

[0056] Over time, the wall may deform or develop further cracks, so the initial model needs to be updated based on the latest 3D scan data. This process involves identifying and adding newly emerging crack points, while marking and removing those that have disappeared. For example, a few months later, the same wall is scanned again using the scanner. New cracks are identified and added to the point cloud model, while some existing cracks disappear due to repairs. The system will mark these points accordingly.

[0057] Based on the updated crack point cloud model, at this stage, it is necessary to extract the feature points of the crack edges. These feature points help to define the actual boundary contour of the crack, thus providing basic data for subsequent analysis. For example, from the updated point cloud, the system detected several key edge points, which together constitute the boundary of the crack, such as the start and end points of the crack.

[0058] By utilizing the extracted edge feature points, an edge feature curve of the crack is constructed, thereby characterizing the crack's direction and morphological changes. Based on the feature curve, the crack can be divided into regions, resulting in multiple crack sub-regions with independent morphological characteristics. For example, by connecting the edge feature points, a curve is formed, showing the crack's direction and morphological changes. This curve divides the crack into several sub-regions, such as the main crack and two branch cracks.

[0059] For each fracture sub-region, its spatial morphological parameters are analyzed, including length, width, depth, and curvature. These parameters can be used to quantify the geometric characteristics of the fracture. For example, after analysis, it was found that the fracture in a certain region has a length of 30 cm, a width of 0.5 cm, a depth of 2 cm, and a curvature of 0.1. These data can reflect the characteristics of the fracture.

[0060] Based on the spatial morphological parameters of each crack sub-region, a comprehensive assessment of the spatial morphology of the entire mortar crack is conducted to obtain an overall assessment result. This step typically involves evaluating the degree of crack development, severity, and potential risks. For example, by analyzing the parameters of all sub-regions, an overall assessment result is obtained, indicating that the crack development of the wall is relatively severe, and maintenance and repair are recommended to prevent further damage.

[0061] In an optional embodiment, the initial fracture point cloud model is dynamically updated based on the current frame's 3D scan data to obtain an updated fracture point cloud model, including:

[0062] Spatial matching is performed between the current frame's 3D scan data and the initial fracture point cloud model to determine overlapping and non-overlapping regions.

[0063] In non-overlapping regions, newly added fracture points are identified and added to the initial fracture point cloud model;

[0064] In the overlapping region, the disappearing fracture points are marked by comparing the position information of the corresponding points in the current frame's 3D scan data with that in the initial fracture point cloud model;

[0065] The marked disappearing fracture points are removed from the initial fracture point cloud model to obtain the updated fracture point cloud model.

[0066] It should be noted that the current frame's 3D scan data is spatially matched with the initial crack point cloud model. The goal of this step is to identify the overlapping and non-overlapping areas between the two. For example, suppose an initial scan of a wall is performed using a laser scanner, resulting in a point cloud model containing cracks. Several months later, the wall is scanned again. During this process, the algorithm calculates the spatial relationship between the two point clouds, determining which parts overlap (i.e., cracks present in the initial model in the current frame data) and which parts are new (i.e., newly added cracks).

[0067] In non-overlapping regions, newly added crack points are identified and added to the initial crack point cloud model. The existence of non-overlapping regions means that the scan data of the current frame contains new cracks that were not detected during the initial scan. For example, suppose a new crack is found in the scan data of the current frame in a non-overlapping region, but there is no relevant information in the initial model. Through the detection of the algorithm, the feature points of this new crack are identified and added to the point cloud model as new crack points.

[0068] In the overlapping region, the positional information of corresponding points in the current frame's 3D scan data and the initial crack point cloud model is compared. Through analysis, it can be marked which crack points have disappeared. Typically, disappeared crack points will be missing in the current frame or their positional information will change significantly. For example, in the overlapping region, the algorithm finds that some crack points that originally existed do not appear in the scan of the current frame, or their positional information has shifted significantly. For instance, if the original coordinates of a crack point are (x1, y1, z1), but the point at the same position in the current frame becomes (x2, y2, z2), and the distance exceeds a preset threshold, the algorithm can determine that the crack may have disappeared and mark it.

[0069] The process involves removing the marked-disappearing crack points from the initial crack point cloud model to obtain an updated crack point cloud model that more accurately reflects the current structural condition. For example, based on the previous analysis, suppose five disappearing crack points were marked in the overlapping area. Now, these points will be removed from the initial point cloud model, resulting in an updated crack point cloud model that includes the initially existing cracks, the identified new cracks, and excludes the crack points that have already disappeared.

[0070] In an optional embodiment, based on the updated crack point cloud model, feature points at the crack edge are extracted, including:

[0071] Neighborhood analysis is performed on the updated fracture point cloud model to determine the set of neighboring points within a preset range for each point;

[0072] Calculate the rate of change of distance between each point and its neighboring point set in each direction;

[0073] Points whose distance change rate exceeds a preset threshold are selected as crack edge feature points.

[0074] It should be noted that performing neighborhood analysis on the updated crack point cloud model first requires determining the set of neighboring points within a preset range for each point. This means that for each point, the algorithm will search for all points within a certain radius around it and treat these points as the set of neighboring points. For example, suppose there is a set of 3D scan data representing the point cloud of a crack. In this point cloud, for a specific point P (e.g., coordinates (x, y, z)), a radius r can be set. Through calculation, it is found that there are 10 points within the radius r, and these points form the set of neighboring points of point P.

[0075] Calculate the rate of change of distance between each point and its neighborhood in each direction. The rate of change of distance reflects the geometric relationship between point P and its neighbors. If the distance between a point and its neighbors changes significantly, it indicates that the point may be located at the edge of a crack. For example, for point P, we can calculate its distance to each point in its neighborhood. If the average distance between the neighbors is davg and the distance from point P to its neighbors is dP, we can calculate the rate of change. If this rate of change exceeds a preset threshold in some directions, then point P can be considered a potential crack edge feature point.

[0076] Selecting points whose distance change rate exceeds a preset threshold as crack edge feature points is crucial because it directly determines which points are considered crack edges. For example, assuming the threshold is set to 0.2, after calculation, it is found that the distance change rate of point P is 0.25, which exceeds the preset threshold, so point P is marked as a crack edge feature point. At the same time, there may be several other points that also meet this condition, and these points together constitute the crack edge features.

[0077] In an optional embodiment, constructing a crack edge feature curve based on crack edge feature points includes:

[0078] The feature points at the edge of the crack are sorted based on their order along the crack's direction.

[0079] A curve fitting algorithm is used to fit the sorted crack edge feature points into a continuous crack edge feature curve.

[0080] It should be noted that the sorting of feature points at the crack edge is based on their order along the crack's direction. This is done to ensure that the final crack edge curve is continuous and accurately reflects the crack's shape. For example, suppose the extracted crack edge feature points have the following coordinates: point A: (x1, y1, z1), point B: (x2, y2, z2), point C: (x3, y3, z3); ​​the crack direction for these points is from left to right. If these points are sorted based on their x-coordinates, the sorted result might be: point A, point B, point C. During the sorting process, the distance and relative position between points may need to be considered to ensure correct alignment along the crack's direction.

[0081] After obtaining the sorted crack edge feature points, the next step is to use a curve fitting algorithm to fit these points into a continuous crack edge feature curve. The purpose of curve fitting is to generate a smooth curve that passes through or approximates these feature points and can effectively represent the edge morphology of the crack. For example, suppose we use polynomial fitting or spline interpolation to perform curve fitting. We can choose quadratic polynomial fitting, substitute the sorted points into the curve equation to obtain a mathematical model, and optimize these parameters using the least squares method so that the fitted curve fits all feature points as closely as possible. Finally, we may obtain a smooth curve that passes through or is very close to the original feature points A, B, and C.

[0082] In an optional embodiment, the crack is divided into multiple crack sub-regions using the crack edge feature curve, including:

[0083] Find curvature abrupt change points on the characteristic curves of the fracture edge; where curvature abrupt change points are used to characterize the locations where the fracture morphology changes.

[0084] Using the curvature abrupt change point as the dividing point, the characteristic curve of the crack edge is divided into multiple curve segments;

[0085] The area enclosed by each curve segment is a crack sub-region.

[0086] It should be noted that the curvature abrupt change point is found on the characteristic curve of the fracture edge. The curvature abrupt change point is a point where the curvature of the curve changes significantly at certain locations. These points usually correspond to the turning point or change of the fracture morphology. For example, suppose the fitted characteristic curve of the fracture edge is a quadratic polynomial curve. In the calculated curvature values, it is found that the curvature value of some points is significantly higher than that of the neighboring points. For example, at point B, the curvature value suddenly increases from 0.1 to 0.5. This indicates that there is a morphological change near this point. Therefore, point B is identified as the curvature abrupt change point.

[0087] Using curvature abrupt change points as dividing points, the characteristic curve of the fracture edge is divided into multiple curve segments; each curve segment represents the morphological characteristics of the fracture within a certain range. For example, suppose there are three curvature abrupt change points: change point P1; change point P2; change point P3; based on these change points, the characteristic curve of the fracture edge can be divided into the following segments: the curve segment from the starting point to P1 (segment A); the curve segment from P1 to P2 (segment B); the curve segment from P2 to P3 (segment C); and the curve segment from P3 to the ending point (segment D).

[0088] The area enclosed by each curve segment is a fracture sub-region. By connecting the endpoints of the curve segment to the fracture centerline (assuming the fracture is on the z-axis and is a planar crack), the boundary of each sub-region can be formed. For example, for the four curve segments mentioned above, assume that they correspond to the following regions: Region R1: enclosed by segment A; Region R2: enclosed by segment B; Region R3: enclosed by segment C; Region R4: enclosed by segment D. Each region R1, R2, R3, R4 represents a different fracture sub-region, which may have different widths, depths, or other geometric characteristics.

[0089] In an optional embodiment, for each fracture sub-region, the spatial morphological parameters of the fracture sub-region are analyzed, including:

[0090] The length of the fracture sub-region is obtained by calculating the spatial distance between the first and last points on the edge feature curve of the fracture sub-region.

[0091] For the width of the crack sub-region, the distance between the characteristic curves of the crack edge is measured at multiple locations in the direction perpendicular to its length, and the average value is taken as the width value;

[0092] The depth of the fracture sub-region is determined by comparing the vertical distance between the bottom point and the top point of the fracture sub-region;

[0093] The curvature of the fracture sub-region is obtained by comprehensive analysis based on the curvature values ​​of each point on the characteristic curve of the fracture edge.

[0094] In an optional embodiment, a comprehensive evaluation of the spatial morphology of mortar fractures is performed based on the spatial morphological parameters of each fracture sub-region, including:

[0095] Weight values ​​are set for different spatial morphology parameters; the weight values ​​are determined based on the importance of each spatial morphology parameter to the fracture morphology.

[0096] The spatial morphological parameters of each fracture sub-region are weighted and summed according to their corresponding weight values ​​to obtain the morphological evaluation value of each fracture sub-region.

[0097] A comprehensive analysis of the morphological evaluation values ​​of all fracture sub-regions was conducted, and the interrelationships between fracture sub-regions were combined to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures.

[0098] In an optional embodiment, the morphological evaluation values ​​of all fracture sub-regions are comprehensively analyzed, and the interrelationships between fracture sub-regions are combined to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures, including:

[0099] Analyze the connection relationships between fracture sub-regions. If multiple fracture sub-regions are interconnected, treat the fracture sub-regions as a whole fracture group.

[0100] For the overall fracture group, the morphological evaluation values ​​of the fracture sub-regions included in the overall fracture group are integrated. The integration method is to take the average value or to perform a weighted average based on the importance of the fracture sub-regions in the whole.

[0101] Based on the integrated results of the overall fracture group and the morphological evaluation values ​​of individual fracture sub-regions, combined with the distribution of fractures in the mortar, a comprehensive evaluation result of the spatial morphology of mortar fractures is obtained.

[0102] It should be noted that identifying the connections between the various fracture sub-regions is crucial. If multiple fracture sub-regions are interconnected, they can be considered as a single fracture group. For example, if fracture sub-regions Z1 and Z2 are structurally connected, while Z3 is independent of these two regions, then Z1 and Z2 can form a single fracture group, while Z3 is evaluated separately. Example: Fracture sub-regions: Z1: Length 5 meters, width 1.77 meters, depth 4 meters, morphological evaluation value 3.361; Z2: Length 6 meters, width 1.5 meters, depth 3 meters, morphological evaluation value 3.49; Z3: Length 4 meters, width 1.9 meters, depth 5 meters, morphological evaluation value 3.19. In this example, it can be observed that Z1 and Z2 are connected, so they are merged into a single fracture group, called fracture group A, while Z3 is independent, called fracture group B.

[0103] For a complete fracture group (e.g., fracture group A), it is necessary to integrate the morphological evaluation values ​​of the fracture sub-regions it contains; integration can be achieved by simple averaging or weighted averaging; if weighted averaging is chosen, the weights can be assigned according to the relative importance of each sub-region in the whole;

[0104] By combining the integrated results of the overall crack group with the morphological evaluation values ​​of individual crack sub-regions (such as 3.19 for crack group B), a comprehensive evaluation of the spatial morphology of the entire mortar crack can be performed. At this point, the distribution of each crack group within the mortar structure needs to be considered, such as the positions of crack groups A and B and their impact on the overall structure. Example of comprehensive evaluation: Crack group A: morphological evaluation value 3.439; Crack group B: morphological evaluation value 3.19. During the comprehensive evaluation, the relative positions of crack groups A and B may be considered. For example, crack group A may be located in the load-bearing part of the mortar, while crack group B may be located in the edge region. In this case, the overall mortar crack spatial morphological evaluation may be biased towards the value of crack group A because it has a greater impact on the structure. Finally, the comprehensive evaluation result can be expressed as a comprehensive score, for example, by weighting the morphological evaluation values, relative positions, and overall distribution of the two groups to obtain the final comprehensive evaluation value. In this example, assuming the final evaluation of the mortar crack spatial morphology is 3.35, it reflects the overall characteristics of the cracks and their impact on the structure.

[0105] In an optional embodiment, after comprehensively evaluating the spatial morphology of mortar fractures based on the spatial morphological parameters of each fracture sub-region to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures, the method further includes:

[0106] During the identification process, if an abnormal change in the crack morphology is detected, a retrospective analysis is performed on the three-dimensional scan data from the initial frame to the current frame.

[0107] By retrospective analysis, the starting frame of the abnormal change in fracture morphology is determined, and the three-dimensional scan data from the starting frame to the current frame is reprocessed. The reprocessing process includes reconstructing the fracture point cloud model, extracting fracture edge feature points, constructing fracture edge feature curves, dividing the fracture into sub-regions, and analyzing spatial morphological parameters.

[0108] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A method for spatial morphology recognition of mortar cracks based on three-dimensional scanning, characterized in that, include: Acquire initial frame 3D scan data, and construct an initial crack point cloud model based on the initial frame 3D scan data; wherein, the initial crack point cloud model includes the spatial point distribution information of mortar cracks in the initial state; Based on the current frame of 3D scan data, the initial fracture point cloud model is dynamically updated to obtain the updated fracture point cloud model; the update process includes the identification and addition of new fracture points and the marking and removal of disappearing fracture points. Based on the updated crack point cloud model, crack edge feature points are extracted; wherein, the crack edge feature points are used to define the boundary contour of the crack. Based on the characteristic points at the crack edge, a crack edge characteristic curve is constructed; wherein, the crack edge characteristic curve is used to characterize the direction and morphological changes of the crack; using the crack edge characteristic curve, the crack is divided into regions to obtain multiple crack sub-regions; each crack sub-region has relatively independent morphological characteristics; For each fracture sub-region, the spatial morphological parameters of the fracture sub-region are analyzed; wherein, the spatial morphological parameters include the length, width, depth and curvature of the fracture sub-region. Based on the spatial morphological parameters of each fracture sub-region, the spatial morphology of mortar fractures is comprehensively evaluated, and the comprehensive evaluation results of the spatial morphology of mortar fractures are obtained.

2. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 1, characterized in that, Based on the current frame's 3D scan data, the initial fracture point cloud model is dynamically updated to obtain the updated fracture point cloud model, including: Spatial matching is performed between the current frame's 3D scan data and the initial fracture point cloud model to determine overlapping and non-overlapping regions. In non-overlapping regions, newly added fracture points are identified and added to the initial fracture point cloud model; In the overlapping region, the disappearing fracture points are marked by comparing the position information of the corresponding points in the current frame's 3D scan data with that in the initial fracture point cloud model; The marked disappearing fracture points are removed from the initial fracture point cloud model to obtain the updated fracture point cloud model.

3. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 2, characterized in that, Based on the updated crack point cloud model, feature points at the crack edges are extracted, including: Neighborhood analysis is performed on the updated fracture point cloud model to determine the set of neighboring points within a preset range for each point; Calculate the rate of change of distance between each point and its neighboring point set in each direction; Points whose distance change rate exceeds a preset threshold are selected as crack edge feature points.

4. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 3, characterized in that, Based on the feature points at the crack edge, construct the crack edge feature curve, including: The feature points at the edge of the crack are sorted based on their order along the crack's direction. A curve fitting algorithm is used to fit the sorted crack edge feature points into a continuous crack edge feature curve.

5. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 4, characterized in that, Using the characteristic curves of the fracture edge, the fracture is divided into regions, resulting in multiple fracture sub-regions, including: Find curvature abrupt change points on the characteristic curve of the fracture edge; wherein, the curvature abrupt change points are used to characterize the locations where the fracture morphology changes; Using the curvature abrupt change point as the dividing point, the characteristic curve of the crack edge is divided into multiple curve segments; The area enclosed by each curve segment is a crack sub-region.

6. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 5, characterized in that, For each fracture sub-region, the spatial morphological parameters of the fracture sub-region are analyzed, including: The length of the fracture sub-region is obtained by calculating the spatial distance between the first and last points on the edge feature curve of the fracture sub-region. For the width of the crack sub-region, the distance between the characteristic curves of the crack edge is measured at multiple locations in the direction perpendicular to its length, and the average value is taken as the width value; The depth of the fracture sub-region is determined by comparing the vertical distance between the bottom point and the top point of the fracture sub-region; The curvature of the fracture sub-region is obtained by comprehensive analysis based on the curvature values ​​of each point on the characteristic curve of the fracture edge.

7. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 6, characterized in that, Based on the spatial morphological parameters of each fracture sub-region, a comprehensive evaluation of the spatial morphology of mortar fractures is conducted, including: Weight values ​​are set for different spatial morphology parameters; wherein, the weight values ​​are determined according to the importance of each spatial morphology parameter to the fracture morphology; The spatial morphological parameters of each fracture sub-region are weighted and summed according to their corresponding weight values ​​to obtain the morphological evaluation value of each fracture sub-region. A comprehensive analysis of the morphological evaluation values ​​of all fracture sub-regions was conducted, and the interrelationships between fracture sub-regions were combined to obtain a comprehensive evaluation result of the spatial morphology of mortar fractures.

8. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 7, characterized in that, A comprehensive analysis of the morphological evaluation values ​​of all fracture sub-regions, combined with the interrelationships between fracture sub-regions, yields a comprehensive evaluation result of the spatial morphology of mortar fractures, including: Analyze the connection relationships between fracture sub-regions. If multiple fracture sub-regions are interconnected, treat the fracture sub-regions as a whole fracture group. For the overall fracture group, the morphological evaluation values ​​of the fracture sub-regions included in the overall fracture group are integrated. The integration method is to take the average value or to perform a weighted average based on the importance of the fracture sub-regions in the whole. Based on the integrated results of the overall fracture group and the morphological evaluation values ​​of individual fracture sub-regions, combined with the distribution of fractures in the mortar, a comprehensive evaluation result of the spatial morphology of mortar fractures is obtained.

9. The method for spatial morphology recognition of mortar cracks based on three-dimensional scanning according to claim 8, characterized in that, After comprehensively evaluating the spatial morphology of mortar fractures based on the spatial morphological parameters of each fracture sub-region, and obtaining the comprehensive evaluation result of the spatial morphology of mortar fractures, the method further includes: During the identification process, if an abnormal change in the crack morphology is detected, a retrospective analysis is performed on the three-dimensional scan data from the initial frame to the current frame. By retrospectively analyzing to determine the starting frame of the abnormal change in fracture morphology, the three-dimensional scan data from the starting frame to the current frame are reprocessed. The reprocessing process includes reconstructing the fracture point cloud model, extracting fracture edge feature points, constructing fracture edge feature curves, dividing the fracture into sub-regions, and analyzing spatial morphological parameters.

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