Crack measurement method and system based on laser ruler, intelligent terminal and storage medium

Abstract

The invention relates to a crack measurement method and system based on a laser ruler, an intelligent terminal and a storage medium, and belongs to the technical field of crack measurement, and the method comprises the steps: obtaining an image of a crack region in real time, and obtaining a detection image; monitoring the position of a first irradiation point of a first laser pen in the crack area in real time according to the detection image; when the first irradiation point is located at the starting point of the crack area, the position of a second irradiation point of a second laser pen in the crack area is monitored in real time according to the detection image; controlling the second irradiation point of the second laser pen to move towards the tail point of the crack area; when the second irradiation point is located at the tail point, the second laser pen is controlled to stop moving; and obtaining the crack length according to the distance between the first laser pen and the second laser pen and the motion record of the second laser pen. The method has the advantage that the crack area can be conveniently measured.

Description

Technical Field

[0001] The present application relates to the field of crack measurement technology, and in particular to a crack measurement method, system, intelligent terminal and storage medium based on a laser ruler. Background Art

[0002] In various building structures, such as bridges, tunnels, subway stations, high-rise buildings and historical buildings, cracks of varying degrees often appear as they age or are affected by external loads, environmental changes, construction defects and other factors. The length of the cracks needs to be measured to assess the structural safety and formulate corresponding reinforcement or repair measures.

[0003] Conventional techniques typically rely on manual labor, using equipment such as aerial platforms to transport inspectors to the crack site. The cracks are then measured using traditional measuring tools. This method relies on inspectors identifying the crack's endpoints and manually reading the values. This process is cumbersome and inefficient, and carries a high degree of operational risk when working in high-altitude, dangerous, or hard-to-reach locations.

[0004] Regarding the above-mentioned related technologies, it is inconvenient to measure the crack area by manually approaching the crack area. Summary of the Invention

[0005] In order to facilitate the measurement of crack areas, the present application provides a crack measurement method, system, intelligent terminal and storage medium based on a laser ruler.

[0006] In a first aspect, the present application provides a crack measurement method based on a laser encoder, which adopts the following technical solutions: A crack measurement method based on a laser ruler, comprising: Acquire images of the crack area in real time to obtain detection images; monitoring in real time the position of the first irradiation point of the first laser pen in the crack area according to the detection image; When the first irradiation point is located at the starting point of the crack area, monitoring the position of the second irradiation point of the second laser pen in the crack area in real time according to the detection image; Controlling the second irradiation point of the second laser pen to move toward the end point of the crack area; When the second irradiation point is located at the end point, controlling the second laser pen to stop moving; The crack length is obtained according to the distance between the first laser pen and the second laser pen and the movement record of the second laser pen.

[0007] By adopting the above technical solution, by acquiring an image of the crack area in real time, when the first irradiation point is located at the starting point of the crack area, the second laser pen is controlled to move so that the second irradiation point moves toward the end point of the crack area. When the second irradiation point is located at the end point, the movement of the second laser pen is stopped. The crack length corresponding to the crack area can be obtained based on the distance between the first laser pen and the second laser pen and the movement record of the second laser pen, and the acquisition method is relatively simple.

[0008] Optionally, controlling the first irradiation point to stay at the starting point; Controlling the second laser pointer to move to an end point of travel with the second irradiation point located in the crack area; Acquire the distance between the first laser pen and the second laser pen to obtain a measured distance; Acquire a ratio between the length of the crack area and the measurement stroke according to the detection image to obtain a length ratio; Determining whether the length ratio is less than a preset length ratio; If yes, control the laser encoder according to the first preset control method; If not, the laser encoder is controlled according to a second preset control method.

[0009] By adopting the above technical solution, by fixing the first irradiation point at the starting point and moving the second laser pen to the end of the stroke, and the second irradiation point is located on the crack area, at this time, the ratio of the length of the crack area to the distance between the first irradiation point and the second irradiation point is obtained by detecting the image, that is, the ratio between the length of the crack area and the measurement stroke, and the length ratio is obtained. Different methods are selected to measure the length of the crack area according to different length ratios, which helps to improve measurement efficiency.

[0010] Optionally, the step of controlling the laser encoder according to the first preset control method includes: controlling the second laser pointer to rotate toward the starting point so that the second irradiation point stays at the starting point; Acquire the angle between the second laser pen and the first laser pen to obtain a first measured angle; Acquire the distance from the laser encoder to the crack area based on the first measurement angle and the measurement stroke to obtain a measured distance; Controlling the second laser pointer to rotate toward the end point so that the second irradiation point stays at the end point; Acquire the angle between the second laser pen and the first laser pen to obtain a second measured angle; Obtaining a second crack length based on the second measurement angle and the measurement distance; The total length is obtained according to the measurement stroke and the second crack length.

[0011] By adopting the above technical solution, when measuring a crack area, the second laser pointer is first controlled to rotate toward the starting point so that the second illumination point coincides with the starting point. At this point, the angle between the second laser pointer and the first laser pointer can be obtained, resulting in the first measured angle. Combining the first measured angle with the distance between the first and second laser pointers, the vertical distance between the laser ruler and the crack area can be calculated. Subsequently, the second laser pointer is controlled to rotate toward the end point so that the second illumination point coincides with the end point, and the current angle is obtained to obtain the second measured angle. By measuring the distance and the second measured angle, the length of the second crack segment can be determined. Finally, the total length of the crack area is determined by adding the measured distance and the length of the second crack segment.

[0012] Optionally, the step of controlling the laser encoder according to the second preset control method includes: In the i-th measurement, the first irradiation point is controlled to stay at the i-th detection point in the crack area, where i is a positive integer with an initial value of 1; Controlling the movement of the second laser pen so that the second irradiation point stays at the i-th target detection point in the crack area; Obtaining the distance between the first laser pen and the second laser pen to obtain the length of the i-th crack; Add the length of the i-th crack to the total length, and the initial value of the total length is 0; Using the i-th target detection point to update the i+1-th detection point; Update i to i+1, and repeat the above five steps until the second irradiation point stops at the end point to obtain the total length.

[0013] By employing this technical solution, during crack measurement, the first and second illumination points are sequentially aligned with the i-th detection point and the i-th target detection point within the crack region, respectively. The length of the i-th crack segment is then determined based on the distance between the first and second laser pointers. After measuring that segment, the length is added to the total length, and the next detection point is updated based on the current target detection point. This process continues, allowing for segmented measurement of the entire crack. The sum of the lengths of all crack segments is then calculated, yielding the total length.

[0014] Optionally, obtaining a measurement path of the crack area according to the measurement image; Obtaining a turning point on the measurement path; Updating the target detection point using the turning point; Dividing the measurement path according to the turning points to obtain measurement sections; Acquire an intermediate detection point according to the measurement section and the measurement stroke; The target detection point is updated using the intermediate detection point.

[0015] By adopting the above technical solution, during the crack measurement process, turning points in the crack area can be identified based on the measurement image, and target detection points are updated based on the turning points, allowing the first laser pen to measure the corresponding crack length using each turning point as a starting point. The measurement path is divided by turning points, and intermediate detection points are obtained based on the measurement section and measurement stroke, and updated as target detection points. This allows the location of the target detection points to be clearly identified when performing segmented measurements of the crack area, which helps to ensure more accurate measurement results.

[0016] Optionally, the turning point is defined as a branch node; Based on the branch node, obtaining a crack path associated with the branch node; controlling the first irradiation point to stay at the branch node; Controlling the laser ruler to rotate so that the second irradiation point stays on the target detection point on the target crack path; acquiring a length of the target crack path according to a distance between the first laser pen and the second laser pen; Repeat the above three steps until all the crack paths are traversed; The lengths of all the crack paths are summed to obtain the total length.

[0017] By adopting the above technical solution, the turning point is defined as a branch node. By controlling the first irradiation point to stay at the branch node and controlling the second irradiation point to stay at the target detection point of the corresponding crack path, the length of the crack path can be obtained. After re-executing the above steps, the first irradiation point stays on all branch nodes, that is, all crack paths can be traversed and measured, so that the total length of the crack area can be obtained more accurately.

[0018] Optionally, acquiring images of the crack area at multiple angles to obtain a detection image set; establishing a three-dimensional model of the crack area based on the image detection set; Selecting a reference segment in the crack region; controlling the laser ruler so that the first irradiation point stays at the starting end point of the reference segment; controlling the movement of the second laser pointer so that the second irradiation point stays at the end point of the reference segment; acquiring length information of the reference segment according to the distance between the first laser pen and the second laser pen; Mapping the length information to the reference segment in the three-dimensional model, and calculating a proportional coefficient between the three-dimensional model and the actual object; Based on the proportional coefficient, the length of the crack region in the three-dimensional model is measured to obtain the total length of the crack region.

[0019] By employing this technical solution, when encountering cracks on non-planar structures, a 3D model of the cracked area is constructed by capturing images from multiple angles. A reference segment within the 3D model is selected and the length of the reference segment, as measured by the laser encoder, is mapped to the 3D model, establishing a proportionality factor between the 3D model and the actual object. Measuring the length of the cracked area within the 3D model based on this proportionality factor helps improve the accuracy of measurement results for non-planar structures.

[0020] In a second aspect, the present application provides a crack measurement system based on a laser encoder, which adopts the following technical solutions: A crack measurement system based on a laser encoder, comprising: Acquisition module, used to acquire detection images and motion records; A memory, used for storing a program of the laser encoder-based crack measurement method; The program in the memory can be loaded and executed by the processor to implement the laser encoder-based crack measurement method.

[0021] By adopting the above technical solution, by acquiring an image of the crack area in real time, when the first irradiation point is located at the starting point of the crack area, the second laser pen is controlled to move so that the second irradiation point moves toward the end point of the crack area. When the second irradiation point is located at the end point, the movement of the second laser pen is stopped. The crack length corresponding to the crack area can be obtained based on the distance between the first laser pen and the second laser pen and the movement record of the second laser pen, and the acquisition method is relatively simple.

[0022] In a third aspect, the present application provides a smart terminal that adopts the following technical solution: An intelligent terminal comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executes the method according to any one of claims 1 to 7.

[0023] In a fourth aspect, the present application provides a computer storage medium capable of storing a corresponding program, which is convenient for measuring a crack area and adopts the following technical solution: A computer-readable storage medium stores a computer program capable of being loaded by a processor and executing any one of the above-mentioned crack measurement methods based on a laser encoder.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. By acquiring an image of the crack area in real time, when the first irradiation point is at the starting point of the crack area, the second laser pen is controlled to move toward the end point of the crack area. When the second irradiation point is at the end point, the second laser pen stops moving. Based on the distance between the first and second laser pen and the movement record of the second laser pen, the crack length corresponding to the crack area can be obtained in a relatively simple manner; 2. Fix the first irradiation point at the starting point and move the second laser pointer to the end of its travel, with the second irradiation point located on the crack area. The image is then inspected to determine the ratio of the length of the crack area to the distance between the first and second irradiation points. This ratio, in other words, the ratio of the length of the crack area to the measurement travel, yields a length ratio. Different methods can be used to measure the length of the crack area based on different length ratios, helping to improve measurement efficiency. 3. When encountering cracks on non-planar structures, a 3D model of the cracked area is constructed by collecting images from multiple angles. A reference segment is selected from the 3D model and the length of the reference segment measured by the laser encoder is mapped to the 3D model, establishing a scaling factor between the 3D model and the actual object. Measuring the length of the cracked area in the 3D model based on this scaling factor helps improve the accuracy of measurement results for non-planar structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural diagram of a laser ruler in an embodiment of the present application.

[0026] Figure 2 This is a flow chart of a crack measurement method based on a laser ruler in an embodiment of the present application.

[0027] Figure 3 It is a flow chart of a segmented measurement method in an embodiment of the present application.

[0028] Figure 4 1 is a flow chart of the steps of controlling the laser encoder according to the first preset control method in an embodiment of the present application.

[0029] Figure 5 2 is a flow chart of the steps of controlling the laser encoder according to the second preset control method in an embodiment of the present application.

[0030] Figure 6 It is a flow chart of a method for acquiring target detection points in an embodiment of the present application.

[0031] Figure 7 It is a flow chart of a crack traversal measurement method in an embodiment of the present application.

[0032] Figure 8 It is a flow chart of a three-dimensional model measurement method in an embodiment of the present application.

[0033] Description of the accompanying drawings: 1. Mounting base; 2. First laser pen; 3. Second laser pen. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of this application more clear, the following Figure 1-8 It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0035] The embodiment of the present application discloses a laser ruler. Figure 1 The laser ruler includes a mounting base 1, a first laser pointer 2 mounted in the mounting base, and a second laser pointer 3 also mounted in the mounting base. The first and second laser pointers 2 and 3 have identical structures. A transmission assembly is located at the bottom of the second laser pointer 3, enabling it to move and rotate on the mounting base 1.

[0036] The embodiment of the present application discloses a crack measurement method based on a laser ruler. Figure 2 , crack measurement methods based on laser encoders include: Step S201: Acquire an image of the crack area in real time to obtain a detection image.

[0037] The crack area is the area where cracks appear in a building. For example, if cracks appear in a bridge, the area where the cracks appear is the crack area.

[0038] The crack area is photographed in real time by a camera to obtain a detection image.

[0039] Step S202: monitoring the position of the first irradiation point of the first laser pen in the crack area in real time according to the detection image.

[0040] Move the laser encoder until it's aligned with the crack. For example, if the crack is in the middle of the bridge near the riverbank, use a tripod or other similar method to secure the laser encoder. If the crack is in the middle of the bridge, use a drone or other similar method to carry the laser encoder and move it so that it's aligned with the crack.

[0041] After the laser ruler is aligned with the crack area, the first laser pointer emits laser light toward the crack area, illuminating the crack area to obtain a first illumination point. The camera can capture the position of the first illumination point in the crack area, thereby monitoring the position of the first illumination point in the crack area in real time based on the detection image.

[0042] Step S203: When the first irradiation point is located at the starting point of the crack area, the position of the second irradiation point of the second laser pen in the crack area is monitored in real time according to the detection image.

[0043] The starting point is the starting point in the crack region, usually an end point in the crack. In this embodiment, for the convenience of describing the crack region, based on the front view of the crack region, the end point of the crack near the left side is the starting point, and the end point of the crack near the right side is the end point.

[0044] When the detection image identifies that the first irradiation point is at the starting point of the crack area, the laser ruler is controlled to stop moving. The second laser pointer is activated to emit laser light toward the crack area, irradiating the crack area, and the position of the second irradiation point in the crack area is monitored in real time through the detection image.

[0045] Step S204: controlling the second irradiation point of the second laser pen to move toward the end point of the crack area.

[0046] The end point is the end point in the crack region, usually the end point of the crack opposite the starting point.

[0047] The second laser pen is controlled to move on the mounting base so that the second irradiation point moves toward the end point of the crack area.

[0048] Step S205: When the second irradiation point is located at the end point, the second laser pen is controlled to stop moving.

[0049] According to the detection image, when the second irradiation point is identified as being at the end of the crack area, the second laser pen is controlled to stop moving. A displacement sensor is provided at the bottom of the second laser pen, and the movement distance of the second laser pen can be obtained according to the displacement sensor.

[0050] Exemplarily, a transmission component, such as a drive motor, is provided at the bottom of the second laser pen, which can drive the second laser pen to move. The drive motor is connected to the controller. When it is recognized that the second irradiation point is at the end point, an instruction is sent to the controller, and the controller controls the drive motor to stop rotating, so that the second laser pen stops moving.

[0051] Step S206: Obtain the crack length according to the distance between the first laser pen and the second laser pen and the movement record of the second laser pen.

[0052] The motion record is a record of the second laser pointer's movement on the mount, including both translation and rotation. The second laser pointer can translate on the mount, parallel to the first laser pointer during translation. The distance between the first and second illumination points is the distance between the first and second laser pointers. The second laser pointer can also rotate, and the distance from the laser ruler to the crack area can be calculated based on the rotation angle and translation distance.

[0053] The crack length is the length of the crack in the crack area.

[0054] Among them, when the motion record only includes movement records, that is, the second laser pen is parallel to the first laser pen, the distance between the first irradiation point and the second irradiation point is equal to the distance between the first laser pen and the second laser pen, and the crack length is also the distance between the first laser pen and the second laser pen.

[0055] By adopting the above technical solution, by acquiring an image of the crack area in real time, when the first irradiation point is located at the starting point of the crack area, the second laser pen is controlled to move so that the second irradiation point moves toward the end point of the crack area. When the second irradiation point is located at the end point, the movement of the second laser pen is stopped. The crack length corresponding to the crack area can be obtained based on the distance between the first laser pen and the second laser pen and the movement record of the second laser pen, and the acquisition method is relatively simple.

[0056] In the following embodiment, the crack length may exceed the measurement range of the laser ruler, resulting in the crack length being obtained through a single measurement. In view of this situation, the embodiment of the present application provides a segmented measurement method, referring to Figure 3 , the method comprising: Step S301: controlling the first irradiation point to stay at the starting point.

[0057] By moving the laser ruler, based on the detection image, when the first irradiation point is located at the starting point of the crack area, the position of the laser ruler is fixed so that the first irradiation point stays at the starting point.

[0058] In this embodiment, the first laser pointer is fixed on one side of the mounting base.

[0059] Step S302: controlling the second laser pointer to move to an end point of travel and positioning the second irradiation point at the crack area.

[0060] The end point of the stroke represents the maximum point of the second laser pointer's movable range on the mounting base. During the movement of the second laser pointer, the second irradiation point must be located over the crack area, and the second laser pointer must only perform translational motion, i.e., parallel to the first laser pointer.

[0061] Step S303: Acquire the distance between the first laser pen and the second laser pen to obtain the measured distance.

[0062] After the second laser pen reaches the end of its travel, the distance between the first and second laser pen can be measured using a displacement sensor, thereby obtaining the measured travel. Furthermore, a slide rail is provided on the mounting base for the second laser pen to move, and the length of the slide rail is the length of the measured travel.

[0063] Step S304: obtaining the ratio between the length of the crack area and the measurement stroke according to the detection image to obtain a length ratio.

[0064] After acquiring an image of the crack area, the overall length of the crack area is determined based on the detected image. The overall length can be determined by marking the starting and ending points of the crack area based on the detected image and calculating the distance between the two points. Finally, the ratio of the overall length to the measured length is calculated to obtain the length ratio.

[0065] For example, the overall length is length P, the measurement stroke is length A, and the length ratio is P / A.

[0066] Step S305: Determine whether the length ratio is less than a preset length ratio.

[0067] The preset length ratio is a preset constant and can be adjusted according to actual needs. In this embodiment, the preset ratio can be set to 2.

[0068] By comparing the length ratio with the preset length ratio, if the length ratio is less than the preset length ratio, step S306 is executed; if the length ratio is not less than the preset length ratio, step S307 is executed.

[0069] Step S306: If yes, control the laser encoder according to the first preset control method.

[0070] If yes, it means that the length ratio is less than the preset length ratio, for example, P / A<2. Based on this situation, the laser encoder is controlled according to the first preset control method to measure the crack length of the crack area in sections. The specific steps of controlling the laser encoder according to the first preset control method can be referred to Figure 4 Steps in the embodiment.

[0071] Step S307: If not, control the laser encoder according to a second preset control method.

[0072] If yes, it means that the length ratio does not have a preset length ratio, for example, P / A≥2. Based on this situation, the laser encoder is controlled according to the second preset control method to measure the crack length of the crack area in sections. The specific steps of controlling the laser encoder according to the second preset control method can be referred to Figure 5Steps in the embodiment.

[0073] By adopting the above technical solution, by fixing the first irradiation point at the starting point and moving the second laser pen to the end of the stroke, and the second irradiation point is located on the crack area, at this time, the ratio of the length of the crack area to the distance between the first irradiation point and the second irradiation point is obtained by detecting the image, that is, the ratio between the length of the crack area and the measurement stroke, and the length ratio is obtained. Different methods are selected to measure the length of the crack area according to different length ratios, which helps to improve measurement efficiency.

[0074] Reference Figure 4 The steps of controlling the laser encoder according to the first preset control method include: Step S401: controlling the second laser pointer to rotate toward the starting point so that the second irradiation point stays at the starting point.

[0075] Optionally, the bottom of the second laser pen has a transmission assembly, and is capable of driving the second laser pen to rotate.

[0076] When the first irradiation point stays at the starting point, the second irradiation point is made to stay at the starting point by rotating the second laser pen toward the starting point. The bottom of the second laser pen is also provided with an angle sensor, which can obtain the rotation angle of the second laser pen.

[0077] Step S402: Acquire the angle between the second laser pen and the first laser pen to obtain a first measured angle.

[0078] The first laser pointer is positioned perpendicular to the length of the mounting base, while the second laser pointer is initially positioned perpendicular to the length of the mounting base, meaning it is parallel to the first. After the second laser pointer rotates, the second illumination point intersects the first illumination point. Therefore, the rotation angle of the second laser pointer is the angle between the second and first laser pointers, i.e., the first measurement angle α.

[0079] Step S403: Obtain the distance from the laser encoder to the crack area based on the first measurement angle and the measurement stroke to obtain the measured distance.

[0080] The angle β between the second laser pointer and the mounting base along the length of the second laser pointer is calculated based on the first measured angle α, where β is the complementary angle of α, and α + β = 90°. The angle γ between the first laser pointer and the mounting base along the length of the second laser pointer is 90°. Therefore, based on γ, β, and the measured distance, the distance from the laser encoder to the crack area can be calculated, resulting in the measured distance: Measured distance = measured distance × tan(β).

[0081] Step S404: controlling the second laser pointer to rotate toward the end point so that the second irradiation point stays at the end point.

[0082] When the length ratio is less than a preset length ratio, the second laser pen is controlled to move toward the end point so that the second irradiation point stays at the end point. The rotation angle of the second laser pen can be obtained by the angle sensor.

[0083] Step S405: Acquire the angle between the second laser pen and the first laser pen to obtain a second measured angle.

[0084] The angle of the second laser pen perpendicular to the length direction of the mounting base is taken as the zero angle point of the angle sensor. After the second laser pen rotates, the rotation angle is obtained according to the angle sensor, and the second measurement angle θ is obtained by subtracting the rotation angle from the first measurement angle α.

[0085] Step S406: Obtain a second crack length based on the second measurement angle and the measurement distance.

[0086] After obtaining the measured distance and the second angle, the second crack length can be calculated according to the Pythagorean theorem, where the second crack length = measured distance × tan(θ).

[0087] Step S407: Obtain the total length according to the measured stroke and the second crack length.

[0088] The measuring distance and the second crack length are added together to obtain the total length of the crack in the crack region.

[0089] By adopting the above technical solution, when measuring a crack area, the second laser pointer is first controlled to rotate toward the starting point so that the second illumination point coincides with the starting point. At this point, the angle between the second laser pointer and the first laser pointer can be obtained, resulting in the first measured angle. Combining the first measured angle with the distance between the first and second laser pointers, the vertical distance between the laser ruler and the crack area can be calculated. Subsequently, the second laser pointer is controlled to rotate toward the end point so that the second illumination point coincides with the end point, and the current angle is obtained to obtain the second measured angle. By measuring the distance and the second measured angle, the length of the second crack segment can be determined. Finally, the total length of the crack area is determined by adding the measured distance and the length of the second crack segment.

[0090] Reference Figure 5 The steps of controlling the laser encoder according to the second preset control method include: Step S501: In the i-th measurement, the first irradiation point is controlled to stay at the i-th detection point in the crack area, where i is a positive integer with an initial value of 1.

[0091] The detection point is the point where the first irradiation point stops, where the first detection point is the starting point. By moving the laser ruler, the first irradiation point stops at the first detection point. i is a positive integer with an initial value of 1.

[0092] Step S502: controlling the movement of the second laser pointer so that the second irradiation point stays at the i-th target detection point in the crack area.

[0093] The target detection point is the point where the second irradiation point stops. The target detection point can be obtained by referring to Figure 6 The steps in the embodiment are as follows: the second laser pen is driven to move, and during the movement, it is always kept parallel to the first laser pen, and when the second irradiation point stops at the target detection point, the second laser pen is controlled to stop moving.

[0094] Step S503: Obtain the distance between the first laser pen and the second laser pen to obtain the length of the i-th crack.

[0095] The distance between the first and second laser pointers can be measured using a displacement sensor located at the bottom of the second laser pointer. The i-th crack length is the length of the crack from the i-th detection point to its corresponding i-th target detection point. When i is 1, the distance is the first crack length.

[0096] Step S504: Add the length of the i-th crack segment to the total length, and the initial value of the total length is 0.

[0097] It refers to the sum of the lengths of all crack segments from the starting point of the crack to the current measurement position. It is used to represent the cumulative length of cracks in the entire crack area. The initial value of the total length is 0.

[0098] Total length = total length + length of the i-th crack. For example, when i is 1, the total length is the length of the first crack, and when i is 2, the total length is the sum of the lengths of the first and second cracks.

[0099] The value of the total length is stored in the storage module, and can be called during the next measurement process.

[0100] Step S505: Use the i-th target detection point to update the (i+1)-th detection point.

[0101] The i+1th detection point is updated using the i-th target detection point, so that in the next measurement, the first irradiation point can irradiate the i-th target detection point, thereby enabling the acquisition of several crack lengths.

[0102] Exemplarily, the first target detection point is updated to the second detection point. When performing the second measurement, the first irradiation point is irradiated on the second detection point, and the second irradiation point is irradiated on the second target detection point, so that the length of the second crack segment can be obtained.

[0103] Step S506: update i to i+1, and repeat the above five steps until the second irradiation point stops at the end point to obtain the total length.

[0104] Update i to i+1. After repeating steps S501, S502, S503, S504 and S505, the length of the i+1th crack section can be obtained. At this time, the total length = the length of the i-th crack section + the length of the i+1th crack section.

[0105] For example, when i is 1, the first irradiation point stays at the starting point, and the second irradiation point stays at the first target detection point. At this time, the distance between the first laser pen and the second laser pen is obtained to obtain the length of the first crack segment, and the total length = the length of the first crack segment. The first target detection point is used to update the second detection point, that is, the position of the second detection point is located at the first target detection point. When i is 2, the first irradiation point stays at the second detection point, and the second irradiation point stays at the second target detection point. At this time, the distance between the first laser pen and the second laser pen is obtained to obtain the length of the second crack segment, and the total length = the length of the first crack segment + the length of the second crack segment. The second target detection point is used to update the third detection point, that is, the position of the third detection point is located at the second target detection point. Similarly, when the second irradiation point stays at the end point of the crack area, the loop is exited. The total length is pulled, which is the sum of the lengths of all crack segments.

[0106] By employing this technical solution, during crack measurement, the first and second illumination points are sequentially aligned with the i-th detection point and the i-th target detection point within the crack region, respectively. The length of the i-th crack segment is then determined based on the distance between the first and second laser pointers. After measuring that segment, the length is added to the total length, and the next detection point is updated based on the current target detection point. This process continues, allowing for segmented measurement of the entire crack. The sum of the lengths of all crack segments is then calculated, yielding the total length.

[0107] In the following embodiment, there may be a turning point in the crack area. Therefore, when obtaining the target detection point, it is necessary to determine the target detection point according to the position of the turning point. The embodiment of the present application provides a method for obtaining the target detection point. Figure 6 , the method comprising: Step S601: Acquire a measurement path of the crack area according to the measurement image.

[0108] The measurement path represents a reference path along which the first irradiation point and the second irradiation point move in the crack extension direction when measuring the crack region, wherein the measurement path corresponds to the shape of the crack region.

[0109] After acquiring an image of the crack area, the crack direction, that is, the shape of the crack, can be identified through an edge detection algorithm to obtain the measurement path.

[0110] Step S602: Obtain turning points on the measurement path.

[0111] The turning point is a point on the measurement path where a change in direction occurs, ie, a point where the angle between adjacent path segments exceeds a preset angle. In this embodiment, the preset angle is a preset constant, which can be set to 15°.

[0112] Step S603: Use the turning point to update the target detection point.

[0113] After obtaining the turning point, the target detection point is updated with it, allowing the second illumination point to remain at the turning point during segmented measurements of the crack area. During subsequent measurements, the target detection point is used to update the detection point, aligning the detection point with the turning point. This allows the first illumination point to remain at the turning point, and measurement of the corresponding crack segment length begins at the turning point. This can be achieved by rotating the laser ruler around the laser pointer's axis, aligning its length with the extension direction of the corresponding crack segment.

[0114] Step S604: Divide the measurement path according to the turning points to obtain measurement sections.

[0115] The measurement path is divided using turning points, and a measurement section is formed between two adjacent turning points, thereby obtaining a plurality of measurement sections, wherein the lengths of the measurement sections may not be the same.

[0116] Step S605: Acquire an intermediate detection point according to the measurement section and measurement stroke.

[0117] The measuring section is divided based on the measuring stroke. The length of a measuring section includes the lengths of several measuring strokes, that is, it has several intermediate detection points.

[0118] For example, the length of the measurement section is S1, the length of the measurement stroke is T1, and both end points of the measurement section are turning points. The formula for calculating the number of measurement strokes within the measurement section is n = S1 / T1, where n is the ratio of the measurement section to the measurement stroke, and n, after rounding, represents the number of intermediate detection points. If n is an integer, one of the intermediate detection points is located at a turning point. If n is not an integer, for example, S1 / T1 = 2.5, rounding 2.5 to 2 gives 2, indicating that there are two intermediate detection points within the measurement section.

[0119] Step S606: Use the intermediate detection points to update the target detection points.

[0120] After obtaining the intermediate detection point, the target detection point is updated with the intermediate detection point so that the second irradiation point can stay on the intermediate detection point when measuring the crack area in sections. In the subsequent measurement process, the target detection point is used to update the detection point, that is, the position of the detection point is the position of the intermediate detection point, so that the first irradiation point stays on the intermediate detection point, and the corresponding crack length is measured starting from the intermediate detection point.

[0121] By adopting the above technical solution, during the crack measurement process, turning points in the crack area can be identified based on the measurement image, and target detection points are updated based on the turning points, allowing the first laser pen to measure the corresponding crack length using each turning point as a starting point. The measurement path is divided by turning points, and intermediate detection points are obtained based on the measurement section and measurement stroke, and updated as target detection points. This allows the location of the target detection points to be clearly identified when performing segmented measurements of the crack area, which helps to ensure more accurate measurement results.

[0122] In the following embodiment, a plurality of crack paths may be associated with a turning point. In view of this situation, the embodiment of the present application provides a crack traversal measurement method, referring to Figure 7 , the method comprising: Step S701: Define a turning point as a branch node.

[0123] A crack path tree is established based on the target detection points and the measurement path. The location of each turning point is defined as a branch node in the crack path tree, which is used to represent the bifurcation point in the crack path tree. The root node of the crack path tree is the starting point.

[0124] Step S702: Based on the branch node, obtain the crack path associated with the branch node.

[0125] The crack path indicates the location of a section of the crack in the crack area.

[0126] According to the detection image, the crack path connected to the current branch node is obtained, which is the crack path associated with the branch node.

[0127] For example, on a branch node A, there are two sub-crack paths a1 and a2 connected, so a1 and a2 are associated paths of the branch node.

[0128] Step S703: Control the first irradiation point to stay at the branch node.

[0129] By moving the laser ruler, the position of the first irradiation point in the crack area is obtained in real time according to the detection image. When the first irradiation point is located on the branch node, the laser ruler is controlled to stop moving.

[0130] Step S704: Control the laser encoder to rotate so that the second irradiation point stays on the target detection point of the target crack path.

[0131] The target crack path is the crack path being measured at the current moment.

[0132] The laser scale is controlled to rotate so that the length direction of the laser scale is parallel to the length direction of the target crack path. The second laser pointer is controlled to move on the mounting base so that the second irradiation point stays on the target detection point of the target crack path.

[0133] Furthermore, if the length of the target crack path is greater than the measurement stroke, refer to Figure 5 The steps in the embodiment are used to obtain the length of the target crack path.

[0134] Step S705: obtaining the length of the target crack path according to the distance between the first laser pen and the second laser pen.

[0135] The second laser pen always remains parallel during the movement, and the distance between the first laser pen and the second laser pen is equal to the distance between the first irradiation point and the second irradiation point, which is the length of the target crack path.

[0136] Step S706: Repeat the above three steps until all crack paths are traversed.

[0137] Repeating steps S703, S704, and S705 allows the length of the crack paths associated with each branch node to be measured, starting with each branch node. Each crack path's length is stored separately. During the traversal process, a depth-first traversal algorithm is used to traverse the crack paths and obtain the corresponding crack path lengths. After traversing all crack paths, step S707 is executed.

[0138] For example, a branch node A is connected to two sub-crack paths a1 and a2. The other end of a1 is connected to branch node B, and the other end of a2 is connected to branch node C. Three sub-crack paths b1, b2, and b3 are connected to branch node B, and one sub-crack path c1 is connected to branch node C. The measurement order is a1-b1-b2-b3-a2-c1.

[0139] Step S707: Sum the lengths of all crack paths to obtain the total length.

[0140] After traversing and completing the measurement of all crack paths, the length value corresponding to each crack path is extracted, and all length values are summed up to obtain the total length of the crack area.

[0141] By adopting the above technical solution, the turning point is defined as a branch node. By controlling the first irradiation point to stay at the branch node and controlling the second irradiation point to stay at the target detection point of the corresponding crack path, the length of the crack path can be obtained. After re-executing the above steps, the first irradiation point stays on all branch nodes, that is, all crack paths can be traversed and measured, so that the total length of the crack area can be obtained more accurately.

[0142] In the following embodiment, if the crack area is not a plane, it is difficult to measure the crack area only by using a laser ruler. In order to solve this problem, the embodiment of the present application provides a three-dimensional model measurement method. Figure 8 , the method comprising: Step S801: Acquire images of the crack area at multiple angles to obtain a detection image set.

[0143] The images at multiple angles may include images taken from different horizontal angles and pitch angles, and these images at different angles are combined to obtain a detection image set.

[0144] For example, if a crack area appears on a bridge pier and is located at a relatively high position, the crack area can be photographed from multiple angles by a drone, and finally a set of detection images of the crack area can be obtained.

[0145] Step S802: establishing a three-dimensional model of the crack area based on the image detection set.

[0146] After acquiring a set of inspection images of the crack region, the crack region is located on the object being inspected. The inspection image set is then de-noised and registered to ensure image consistency. Three-dimensional modeling of the object being inspected is then performed based on the inspection image set, resulting in a 3D model of the object being inspected. An edge detection algorithm is used to identify the boundaries of the crack region. Coordinate mapping of the crack region is performed based on the inspection image set to obtain the 3D coordinates of the crack region. Based on the 3D coordinates, the boundaries of the crack region are added to the 3D model of the object being inspected, resulting in a 3D model of the crack region.

[0147] Step S803: Select a reference segment in the crack area.

[0148] The reference segment is a section of the crack that can be directly measured by the laser encoder. For example, if there is a horizontal crack in the crack area, this section is selected as the reference segment.

[0149] Step S804: Control the laser encoder so that the first irradiation point stays at the starting end point of the reference segment.

[0150] The starting endpoint is the endpoint on one side of the starting point of the reference segment. In this embodiment, based on the front view of the reference segment, the endpoint on the left is the starting endpoint, and the endpoint on the right is the ending endpoint.

[0151] The laser ruler is controlled to move. According to the detection image, when the first irradiation point stops at the starting endpoint, the laser ruler is controlled to stop moving.

[0152] Step S805: Control the movement of the second laser pointer so that the second irradiation point stays at the end point of the reference segment.

[0153] The second laser pointer is controlled to move on the mounting base so that the second irradiation point stops at the end point of the reference segment. The distance between the first irradiation point and the second irradiation point is the length of the reference segment.

[0154] Step S806: Acquire the length information of the reference segment according to the distance between the first laser pointer and the second laser pointer.

[0155] The second laser pen always remains parallel to the first laser pen during movement. The distance between the first irradiation point and the second irradiation point is the distance between the first laser pen and the second laser pen. The distance between the second laser pen and the first laser pen is obtained according to the displacement sensor of the second laser pen, thereby obtaining the length information of the reference segment.

[0156] Step S807: Map the length information to the reference segment in the three-dimensional model, and calculate the proportional coefficient between the three-dimensional model and the actual object.

[0157] The proportionality factor refers to the length ratio between the crack area in the 3D model and the crack area on the actual object, and is used to restore the measurement results in the 3D model to the actual length on the actual object.

[0158] By mapping the length information onto the reference segment of the 3D model, the proportional relationship between the length of the reference segment in the actual object and the length of the reference segment in the 3D model can be obtained, and the proportional coefficient between the 3D model and the actual object can be obtained based on the proportional relationship.

[0159] For example, the length of the reference segment measured by the laser ruler is 25 cm, and the length of the reference segment in the three-dimensional model is 50 pixels, so the scale factor is 0.5 cm / pixel.

[0160] Step S808: Based on the proportional coefficient, the length of the crack area in the three-dimensional model is measured to obtain the total length of the crack area.

[0161] In the 3D model, the crack region is composed of continuous pixel units. Using an image processing algorithm, the cumulative length of all crack pixels in the crack region is obtained to determine the total pixel length of the crack region in the 3D model. This total pixel length is then multiplied by the scaling factor to determine the total length of the crack region in the actual object.

[0162] For example, in a three-dimensional model, there is a crack area including several cracks, and the total number of pixels occupied by all cracks is 1200 pixel units. When the scale factor is 0.5 cm / pixel, the total length of the crack area is 600 cm.

[0163] By employing this technical solution, when encountering cracks on non-planar structures, a 3D model of the cracked area is constructed by capturing images from multiple angles. A reference segment within the 3D model is selected and the length of the reference segment, as measured by the laser encoder, is mapped to the 3D model, establishing a proportionality factor between the 3D model and the actual object. Measuring the length of the cracked area within the 3D model based on this proportionality factor helps improve the accuracy of measurement results for non-planar structures.

[0164] Based on the same inventive concept, an embodiment of the present application provides a crack measurement system based on a laser encoder, comprising: Acquisition module, used to acquire detection images and motion records; A memory, used for storing a program of the laser encoder-based crack measurement method; The program in the memory can be loaded and executed by the processor to implement the above-mentioned crack measurement method based on the laser encoder.

[0165] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0166] An embodiment of the present application provides a computer-readable storage medium storing a computer program that can be loaded by a processor and executed by a laser encoder-based crack measurement method.

[0167] Computer storage media include, for example, various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0168] Based on the same inventive concept, an embodiment of the present application provides an intelligent terminal, including a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute a crack measurement method based on a laser ruler.

[0169] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0170] The above are all preferred embodiments of the present application and are not intended to limit the scope of protection of this application. Unless otherwise specified, any feature disclosed in this specification (including the abstract and drawings) may be replaced by other equivalent or similar features. In other words, unless otherwise specified, each feature is merely an example of a series of equivalent or similar features.

Claims

1. A crack measurement method based on a laser ruler, characterized in that: include: Acquire images of the crack area in real time to obtain detection images; monitoring in real time the position of the first irradiation point of the first laser pen in the crack area according to the detection image; When the first irradiation point is located at the starting point of the crack area, monitoring the position of the second irradiation point of the second laser pen in the crack area in real time according to the detection image; Controlling the second irradiation point of the second laser pen to move toward the end point of the crack area; When the second irradiation point is located at the end point, controlling the second laser pen to stop moving; The crack length is obtained according to the distance between the first laser pen and the second laser pen and the movement record of the second laser pen.

2. The crack measurement method based on a laser ruler according to claim 1, characterized in that: The method further comprises: controlling the first irradiation point to stay at the starting point; Controlling the second laser pointer to move to an end point of travel with the second irradiation point located in the crack area; Acquire the distance between the first laser pen and the second laser pen to obtain a measured distance; Acquire a ratio between the length of the crack area and the measurement stroke according to the detection image to obtain a length ratio; Determining whether the length ratio is less than a preset length ratio; If yes, control the laser encoder according to the first preset control method; If not, the laser encoder is controlled according to a second preset control method.

3. The crack measurement method based on a laser ruler according to claim 2, characterized in that: The step of controlling the laser encoder according to the first preset control method includes: controlling the second laser pointer to rotate toward the starting point so that the second irradiation point stays at the starting point; Acquire the angle between the second laser pen and the first laser pen to obtain a first measured angle; Acquire the distance from the laser encoder to the crack area based on the first measurement angle and the measurement stroke to obtain a measured distance; Controlling the second laser pointer to rotate toward the end point so that the second irradiation point stays at the end point; Acquire the angle between the second laser pen and the first laser pen to obtain a second measured angle; Obtaining a second crack length based on the second measurement angle and the measurement distance; The total length is obtained according to the measurement stroke and the second crack length.

4. The crack measurement method based on a laser ruler according to claim 2, characterized in that: The step of controlling the laser ruler according to the second preset control method includes: In the i-th measurement, the first irradiation point is controlled to stay at the i-th detection point in the crack area, where i is a positive integer with an initial value of 1; Controlling the movement of the second laser pen so that the second irradiation point stays at the i-th target detection point in the crack area; Obtaining the distance between the first laser pen and the second laser pen to obtain the length of the i-th crack; Add the length of the i-th crack to the total length, and the initial value of the total length is 0; Using the i-th target detection point to update the i+1-th detection point; Update i to i+1, and repeat the above five steps until the second irradiation point stops at the end point to obtain the total length.

5. The crack measurement method based on a laser ruler according to claim 4, characterized in that: The method further comprises: acquiring a measurement path of the crack area according to the measurement image; Obtaining a turning point on the measurement path; Updating the target detection point using the turning point; Dividing the measurement path according to the turning points to obtain measurement sections; Acquire an intermediate detection point according to the measurement section and the measurement stroke; The target detection point is updated using the intermediate detection point.

6. The crack measurement method based on a laser encoder according to claim 5, characterized in that: The method further comprises: The turning point is defined as a branch node; Based on the branch node, obtaining a crack path associated with the branch node; controlling the first irradiation point to stay at the branch node; Controlling the laser ruler to rotate so that the second irradiation point stays on the target detection point on the target crack path; acquiring a length of the target crack path according to a distance between the first laser pen and the second laser pen; Repeat the above three steps until all the crack paths are traversed; The lengths of all the crack paths are summed to obtain the total length.

7. The crack measurement method based on a laser encoder according to claim 1, characterized in that: The method further comprises: Acquire images of the crack area at multiple angles to obtain a detection image set; establishing a three-dimensional model of the crack area based on the image detection set; Selecting a reference segment in the crack region; controlling the laser ruler so that the first irradiation point stays at the starting end point of the reference segment; controlling the movement of the second laser pointer so that the second irradiation point stays at the end point of the reference segment; acquiring length information of the reference segment according to the distance between the first laser pen and the second laser pen; Mapping the length information to the reference segment in the three-dimensional model, and calculating a proportionality coefficient between the three-dimensional model and the actual object; Based on the proportional coefficient, the length of the crack region in the three-dimensional model is measured to obtain the total length of the crack region.

8. A crack measurement system based on a laser ruler, characterized in that: The system is used to perform the crack measurement method based on a laser encoder according to any one of claims 1 to 7, comprising: Acquisition module, used to acquire detection images and motion records; A memory, used for storing a program of the laser encoder-based crack measurement method; The program in the memory can be loaded and executed by the processor to implement the laser encoder-based crack measurement method.

9. An intelligent terminal, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that A computer program is stored which can be loaded by a processor and execute the method according to any one of claims 1 to 7.

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