Three-dimensional laser scanning fixed system for deformation detection of engineering rock mass and test method thereof

Abstract

The application discloses a three-dimensional laser scanning fixing system for engineering rock mass deformation detection and a testing method thereof, relates to the field of engineering rock mass deformation monitoring, and comprises a cylindrical main base and a cylindrical auxiliary base. The cylindrical main base comprises a three-dimensional laser scanner arranged on the top surface of the cylindrical main base in the axial direction, prisms arranged on the top surface of the cylindrical main base and respectively arranged equidistantly in the horizontal direction on the two sides of the three-dimensional laser scanner, and a lifting unit arranged in the cylindrical main base and arranged in the axial direction in a lifting manner. The bottom surface of the cylindrical main base is provided with a fixing seat. The cylindrical auxiliary base comprises a target ball arranged on the top surface of the cylindrical auxiliary base. The application is aimed at the complex traffic conditions of some engineering rock mass detection projects, which are not conducive to the development of three-dimensional laser deformation scanning. The main base and the auxiliary base fixing devices are buried underground, and the lifting design is used to realize that the main base does not cause influence on the traffic conditions in the non-working state.

Description

Technical Field

[0001] This invention relates to the field of engineering rock mass deformation monitoring, specifically a three-dimensional laser scanning fixation system and its testing method for engineering rock mass deformation detection. Background Technology

[0002] Deformation of engineering rock masses is a direct reflection of their physical and mechanical properties. Monitoring this deformation can aid in assessing the stability and safety of the rock mass structure. Traditional engineering rock mass deformation detection techniques suffer from low efficiency, a limited number of measuring points, and data acquisition delays and limitations. Three-dimensional laser scanning, on the other hand, offers high efficiency and precision, providing deformation data with temporal consistency and spatial integrity. Therefore, utilizing three-dimensional laser scanning technology for engineering rock mass deformation detection has practical and significant engineering implications.

[0003] When using 3D laser scanning to detect deformation in engineering rock masses, if two or more scans cannot be performed precisely at the same spatial location, point cloud registration is required during data processing. Existing fixed-point scanning devices are prone to interfering with traffic conditions and are unsuitable for complex construction sites. Data processing without fixed-point assistance is time-consuming and labor-intensive, and cannot guarantee real-time monitoring to understand deformation trends. Therefore, the problem of minimizing the impact on site environmental conditions while assisting 3D laser scanning for positioning is a pressing issue to be addressed when detecting deformation in engineering rock masses. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a three-dimensional laser scanning fixation system and its testing method for detecting deformation of engineering rock masses. This system can acquire point cloud data of engineering rock masses multiple times for deformation calculation without affecting on-site traffic conditions, and ensure that each scan is performed at the same spatial location.

[0005] The three-dimensional laser scanning and fixing system for detecting deformation of engineering rock mass includes a cylindrical main base and a cylindrical secondary base, which are arranged side by side and buried underground. The cylindrical main base includes a three-dimensional laser scanner axially mounted on its top surface, prisms equidistantly positioned on both sides of the three-dimensional laser scanner on its top surface, and a lifting unit axially movable inside the cylindrical main base. A fixing seat is provided on the bottom surface of the cylinder, and the fixing seat is bolted to the fixing end of the lifting unit. The cylindrical secondary base includes a target ball mounted on its top surface.

[0006] Furthermore, the cylindrical main base also includes a prism slot disposed on the top surface of the cylindrical main base and corresponding to the fixing part of the prism, the prism being fixed to the cylindrical main base through the prism slot; the cylindrical main base also includes a 3D laser scanner slot disposed on the top surface of the cylindrical main base and corresponding to the fixing part of the 3D laser scanner, the 3D laser scanner being fixed to the cylindrical main base through the 3D laser scanner slot.

[0007] Furthermore, the cylindrical sub-base also includes a target ball slot disposed on the top surface of the cylindrical sub-base and corresponding to the fixing part of the target ball, wherein the target ball is fixed to the cylindrical sub-base through the target ball slot.

[0008] Furthermore, the lifting unit includes a lifting platform, a lifting bracket disposed below the lifting platform for lifting and supporting the lifting platform, a control device electrically connected to the lifting bracket, and a support disposed at the bottom of the lifting bracket, wherein the lifting bracket and the support are fixedly connected by bolts.

[0009] Furthermore, the lifting support includes an inner tube and a hollow outer tube, wherein the hollow outer tube is sleeved on the inner tube and fixed relative to it by bolts, and the bottom of the hollow outer tube is fixedly connected to the support bolts.

[0010] Furthermore, the control device includes a protective housing for encapsulation and a power supply, control chip, and wireless communication module located within the protective housing.

[0011] Furthermore, as a preferred embodiment, a three-dimensional laser scanning fixed testing method for detecting deformation of engineering rock mass is proposed, which specifically includes the following steps: S1. Install the target ball into the target ball slot on the top surface of the cylindrical sub-base, and raise the lifting unit to the specified height via wireless signal control. Install the 3D laser scanner and prism into the 3D laser scanner slot and prism slot on the top surface of the cylindrical main base, respectively. Input the scanning parameters according to the size of the rock mass and the relative orientation of the rock mass and the main base, and start the 3D laser scanner to acquire point cloud data. S2. Input the acquired point cloud data into the point cloud processing software. Reposition the point cloud data using APM based on the coordinate information of the prism and target sphere. Perform point cloud segmentation and point cloud filtering on the repositioned point cloud data. Extract the point cloud cross-sectional data as needed, and perform point cloud projection processing on the extracted cross-sectional data. Divide the data obtained from two or more point cloud projections of the same cross-section into zones and perform uniform interpolation. Perform deformation calculation, take the average value of the deformation of each zone and output the result to obtain the deformation results of each region of the rock mass.

[0012] Furthermore, in step S2, the specific process of performing point cloud segmentation and point cloud filtering on the point cloud data after positioning includes the following steps: S201. Perform point cloud segmentation on the point cloud data after positioning is completed, delete redundant point cloud data that is not for the detected object, and retain the required point cloud data; S202. Perform point cloud filtering processing, filtering out nonlinear noise points while ensuring data stability using median filtering. Specifically: Among them, the Indicates the median output, the The coordinate grayscale value, the Indicates median processing; S203. Perform mean filtering on the point cloud data after median filtering to reduce noise and make the point cloud data smoother. Specifically: Among them, the Represents the mean filter output, the Represents the number of points in the neighborhood, the Representing the neighborhood, the Represents the initial grayscale value; S204. Extract the filtered point cloud cross-sectional data, and establish a reference surface based on the extracted point cloud cross-sectional data type. Project the point cloud cross-sectional data onto the reference surface to complete the point cloud projection processing. Perform point cloud projection partitioning and Kriging interpolation on the same cross-section two or more times, compare and calculate the interpolation results of the same partition two or more times, and obtain the corresponding deformation amount. Then, take the average value of the deformation amount of each partition and output the result to obtain the deformation results of each region of the engineering rock mass.

[0013] The beneficial effects of this invention are: (1) According to the advantages of three-dimensional laser scanning technology in the detection of deformation of engineering rock mass, such as automatic, high efficiency and non-contact, which are not available in traditional detection technology, the cumbersome data processing steps hinder the realization of real-time detection and early warning of deformation of engineering rock mass. This invention saves the processing time of point cloud registration by fixing the spatial position of the three-dimensional laser scanner, prism and target ball. (2) In view of the fact that some engineering rock mass detection projects have complex on-site traffic conditions that are not conducive to carrying out three-dimensional laser deformation scanning, the present invention buries the main and auxiliary base fixing devices underground and uses the lifting design to ensure that the main base does not affect the on-site traffic conditions when it is not in operation. Attached Figure Description

[0014] Figure 1 A structural diagram of the main base; Figure 2This is a schematic diagram of the sub-base structure; Figure 3 A schematic diagram of the upper surface structure of the main base in its non-working state; Figure 4 This is a schematic diagram of the upper surface structure of the sub-base in its non-working state. Figure 5 A flowchart illustrating an engineering rock mass deformation detection method provided in this application embodiment; Figure 6 This is a schematic diagram of a tunnel rock mass deformation test as shown in one embodiment; Figure 7 This is a schematic diagram illustrating a three-dimensional laser scanning method for slope deformation, as an exemplary embodiment. In the diagram: 1-Cylindrical main base, 2-3D laser scanner, 3-Prism, 4-Cylindrical secondary base, 5-Target ball, 6-Lifting platform, 7-Lifting bracket, 8-Control equipment, 9-Support. Detailed Implementation

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of the invention, and not all of them. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0017] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention. It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0018] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0019] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0020] like Figure 1 As shown, a three-dimensional laser scanning and fixing system for detecting deformation of engineering rock mass includes a cylindrical main base 1 and a cylindrical secondary base 4, which are arranged side by side and buried underground. The cylindrical main base 1 includes a three-dimensional laser scanner 2 axially mounted on the top surface of the cylindrical main base 1, prisms 3 equidistantly mounted on the top surface of the cylindrical main base 1 and on both sides of the three-dimensional laser scanner 2 equidistantly along the horizontal direction, and a lifting unit axially movable inside the cylindrical main base 1. A fixing seat is provided on the bottom surface of the cylinder, and the fixing seat is bolted to the fixing end of the lifting unit. The cylindrical secondary base 4 includes a target ball 5 mounted on the top surface of the cylindrical secondary base. In the working state, the control device 8 of the cylindrical main base 1 sends a wireless signal to the lifting bracket 7. The two sets of brackets of the lifting bracket 7 rise and fall synchronously to ensure that the lifting platform 6 is raised to the specified height in a horizontal state, ensuring that the 3D laser scanner 2 is in the same spatial position for each inspection. After installing the 3D laser scanner 2, prism 3 and target ball 5 in the corresponding 3D laser scanner slot, prism slot and target ball slot on the upper surface of the cylindrical main base 1 and the cylindrical sub-base 4, the work can begin. In the non-working state, the 3D laser scanner 2, prism 3 and target ball 5 are removed from the cylindrical main base 1 and the cylindrical sub-base 4. The control device 8 of the cylindrical main base 1 sends a signal to the lifting bracket 7, and the lifting bracket 7 lowers the lifting platform 6 so that the upper surface of the main base is once again at the same level as the ground.

[0021] Furthermore, the cylindrical main base 1 also includes a prism slot disposed on the top surface of the cylindrical main base and corresponding to the fixing part of the prism 3, the prism 3 being fixed to the cylindrical main base 1 through the prism slot; the cylindrical main base 1 also includes a 3D laser scanner slot disposed on the top surface of the cylindrical main base and corresponding to the fixing part of the 3D laser scanner 2, the 3D laser scanner being fixed to the cylindrical main base 1 through the 3D laser scanner slot.

[0022] Furthermore, the cylindrical sub-base 4 also includes a target ball slot disposed on the top surface of the cylindrical sub-base and corresponding to the fixing part of the target ball 5, wherein the target ball 5 is fixed to the cylindrical sub-base 4 through the target ball slot.

[0023] Furthermore, the lifting unit includes a lifting platform 6, a lifting bracket 7 disposed below the lifting platform 6 for lifting and supporting the lifting platform 6, a control device 8 electrically connected to the lifting bracket 7, and a support 9 disposed at the bottom of the lifting bracket 7, wherein the lifting bracket 7 and the support 9 are bolted together.

[0024] Furthermore, the lifting bracket 7 includes an inner bracket tube and a hollow outer bracket tube. The hollow outer bracket tube is fitted onto the inner bracket tube and fixed relative to it with bolts. The bottom of the hollow outer bracket tube is bolted to the support 9. In one specific embodiment, the slot is a rectangular hole with two parallel sides and two bevels for inserting a corresponding protrusion on the fixing part. The fixing part has a protrusion corresponding to the slot, typically a parallelogram-shaped post, for inserting into the slot to form a connection between the slot and the fixing base. After insertion into the slot, bolts are used to secure it to ensure it does not move or loosen. In another specific embodiment, the structure of the slot and fixing part in the above embodiments can be replaced with a snap-fit ​​connection. Specifically, the slot is a snap-fit ​​groove, and the fixing part has a snap-fit ​​corresponding to the snap-fit ​​groove. The fixing part and the slot are snap-fit ​​connected and further fixed by bolts or other means.

[0025] Furthermore, the control device 8 includes a protective casing for encapsulation, and a power supply, a control chip, and a wireless communication module located within the casing. Specifically, in this embodiment, the power supply and the control chip are connected via a power line, and the control chip obtains stable voltage and current through the power line. The control chip communicates wirelessly with other devices through the wireless communication module. The control chip and the wireless communication module are connected via a serial port or SPI interface, and the control chip can control the transmission and reception of the wireless communication module through these interfaces. The power supply, control chip, and wireless communication module are typically integrated on the same circuit board, forming a complete electronic device.

[0026] Furthermore, a preferred embodiment of the above-described embodiments is proposed, specifically, a method for installing a three-dimensional laser scanner 2 fixing system for detecting engineering rock mass deformation, comprising: System site selection: The system burial site should be determined according to the height and size of the rock mass of the detection project. The distance between the main base and the detection object should be less than 50m, and the maximum incident angle of the detection object should be controlled within 60°. Trench excavation and system installation: At the selected site, vertically excavate a trench according to the system dimensions and ensure that the system can be installed upright in it. At the same time, the upper surface of the system should be kept at the same level as the ground as possible.

[0027] Furthermore, as a preferred embodiment, a three-dimensional laser scanning fixed testing method for detecting deformation of engineering rock mass is proposed, which specifically includes the following steps: S1. Install the target ball 5 into the target ball slot on the top surface of the cylindrical sub-base, and raise it to the specified height by controlling the lifting unit through wireless signal. Install the 3D laser scanner 2 and prism 3 into the 3D laser scanner slot and prism slot on the top surface of the cylindrical main base, respectively. Input the scanning parameters according to the size of the rock mass and the relative orientation of the rock mass and the cylindrical main base 1, and start the 3D laser scanner 2 to acquire point cloud data. S2. Input the acquired point cloud data into the point cloud processing software. Based on the coordinate information of prism 3 and target sphere 5, perform APM repositioning. Perform point cloud segmentation and point cloud filtering on the point cloud data after positioning. Extract point cloud cross-sectional data as required, and perform point cloud projection processing on the extracted cross-sectional data. Perform partitioning and uniform interpolation on the point cloud data obtained from two or more point cloud projections of the same cross-section, and perform deformation calculation. Take the average value of the deformation of each partition and output the result to obtain the deformation results of each region of the rock mass.

[0028] Furthermore, in step S2, the specific process of performing point cloud segmentation and point cloud filtering on the point cloud data after positioning includes the following steps: S201. Perform point cloud segmentation on the point cloud data after positioning is completed, delete redundant point cloud data that is not for the detected object, and retain the required point cloud data; S202. Perform point cloud filtering processing, filtering out nonlinear noise points while ensuring data stability using median filtering. Specifically: Among them, the Indicates the median output, the The coordinate grayscale value, the Indicates median processing; S203. Perform mean filtering on the point cloud data after median filtering to reduce noise and make the point cloud data smoother. Specifically: Among them, the Represents the mean filter output, the Represents the number of points in the neighborhood, the Representing the neighborhood, the Represents the initial grayscale value; S204. Extract the filtered point cloud cross-sectional data, and establish a reference surface based on the extracted point cloud cross-sectional data type. Project the point cloud cross-sectional data onto the reference surface to complete the point cloud projection processing. Perform point cloud projection partitioning and Kriging interpolation on the same cross-section two or more times, compare and calculate the interpolation results of the same partition two or more times, and obtain the corresponding deformation amount. Then, take the average value of the deformation amount of each partition and output the result to obtain the deformation results of each region of the engineering rock mass.

[0029] Furthermore, a preferred embodiment of the above-described embodiments is proposed. Specifically, the system and method of the present invention are applied to the deformation detection of geological defects in a section of a tunnel. A cylindrical main base 1 is installed at the location of the geological defect in the engineering rock mass (chainage K1+630). A three-dimensional laser scanner 2 is installed on the cylindrical main base 1, and the intelligent unit is debugged according to the site conditions. A cylindrical secondary base 4 is installed at chainage K1+632. From the time of installation, environmental data is acquired by environmental monitoring equipment after each blast at the tunnel face. A scan is performed when the environment is suitable, and the deformation of the rock mass from chainage K1+610 to K1+640 of the tunnel is detected in real time. The results of one detection are shown below. Figure 6 As shown.

[0030] Furthermore, a preferred embodiment of the above-described embodiments is proposed. Specifically, the system and method of the present invention are applied to the deformation detection of a potentially hazardous slope rock mass. Since the slope rock mass detection area is large, multiple systems can be set up to jointly complete the deformation detection of the slope rock mass, based on the appropriate scanning area of ​​the system and the location of the slope rock mass. Multiple data acquired from the same set of scans are stitched together using ICP registration, as follows: Among them, the The optimization function representing the algorithm's output, the This represents the number of point pairs between two point clouds. This represents a point in the source point cloud. Indicates the concentration of target points in the cloud and The nearest point, the , These represent the rotation matrix and the translation matrix, respectively. After the system of this embodiment is installed, the intelligent units of multiple systems need to be debugged in a unified manner so that each scan of multiple systems is performed simultaneously to jointly complete the slope rock mass deformation detection.

[0031] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A three-dimensional laser scanning fixing system for detecting deformation of engineering rock mass, comprising a cylindrical main base (1) and a cylindrical secondary base (4), wherein the cylindrical main base (1) and the cylindrical secondary base (4) are arranged side by side, and the cylindrical main base (1) and the cylindrical secondary base (4) are respectively buried underground, characterized in that, The cylindrical main base (1) includes a three-dimensional laser scanner (2) arranged axially on the top surface of the cylindrical main base, prisms (3) arranged on the top surface of the cylindrical main base and equidistantly arranged on both sides of the three-dimensional laser scanner (2) in the horizontal direction, and a lifting unit arranged inside the cylindrical main base (1) and axially movable. The bottom surface of the cylinder is provided with a fixed seat, and the fixed seat is bolted to the fixed end of the lifting unit. The cylindrical sub-base (4) includes a target ball (5) arranged on the top surface of the cylindrical sub-base.

2. The three-dimensional laser scanning and fixing system for detecting engineering rock mass deformation as described in claim 1, characterized in that, The cylindrical main base (1) also includes a prism slot disposed on the top surface of the cylindrical main base and corresponding to the fixing part of the prism (3). The prism (3) is fixed to the cylindrical main base (1) through the prism slot. The cylindrical main base (1) also includes a three-dimensional laser scanner slot disposed on the top surface of the cylindrical main base and corresponding to the fixing part of the three-dimensional laser scanner (2). The three-dimensional laser scanner (2) is fixed to the cylindrical main base (1) through the three-dimensional laser scanner slot.

3. The three-dimensional laser scanning and fixing system for detecting engineering rock mass deformation as described in claim 1, characterized in that, The cylindrical sub-base (4) also includes a target ball slot disposed on the top surface of the cylindrical sub-base and corresponding to the fixing part of the target ball (5). The target ball (5) is fixed to the cylindrical sub-base (4) through the target ball slot.

4. The three-dimensional laser scanning and fixing system for detecting engineering rock mass deformation as described in claim 1, characterized in that, The lifting unit includes a lifting platform (6), a lifting bracket (7) located below the lifting platform (6) for lifting and supporting the lifting platform (6), a control device (8) electrically connected to the lifting bracket (7), and a support (9) located at the bottom of the lifting bracket (7), wherein the lifting bracket (7) and the support (9) are bolted together.

5. The three-dimensional laser scanning and fixing system for detecting engineering rock mass deformation as described in claim 4, characterized in that, The lifting support (7) includes an inner tube and a hollow outer tube. The hollow outer tube is sleeved on the inner tube and fixed relative to it by bolts. The bottom of the hollow outer tube is bolted to the support (9).

6. The three-dimensional laser scanning and fixing system for detecting engineering rock mass deformation as described in claim 4, characterized in that, The control device (8) includes a protective shell for encapsulation and a power supply, control chip, and wireless communication module located inside the protective shell.

7. A three-dimensional laser scanning and fixing test method for detecting deformation of engineering rock mass, the method being implemented based on the three-dimensional laser scanning and fixing system for detecting deformation of engineering rock mass as described in any one of claims 1-6, characterized in that, The method specifically includes the following steps: S1. Install the target ball (5) into the target ball slot on the top surface of the cylindrical sub-base, and raise the lifting unit to the specified height by controlling the wireless signal. Install the three-dimensional laser scanner (2) and prism (3) into the three-dimensional laser scanner slot and prism slot on the top surface of the cylindrical main base, respectively. Input the scanning parameters according to the size of the scanned rock mass and the relative orientation of the scanned rock mass and the cylindrical main base (1), and start the three-dimensional laser scanner (2) to obtain point cloud data. S2. Input the acquired point cloud data into the point cloud processing software, reposition the point cloud data according to the coordinate information of the prism (3) and the target ball (5) using APM, perform point cloud segmentation and point cloud filtering on the point cloud data that has been positioned, extract the point cloud cross section data according to the requirements, and perform point cloud projection processing on the extracted cross section data; partition and uniformly interpolate the data obtained from two or more point cloud projections of the same cross section, and perform deformation calculation, take the average value of the deformation of each partition and output the result to obtain the deformation results of each region of the rock mass.

8. The three-dimensional laser scanning fixed test method for detecting deformation of engineering rock mass as described in claim 7, characterized in that, In step S2, the specific process of performing point cloud segmentation and point cloud filtering on the point cloud data after positioning includes the following steps: S201. Perform point cloud segmentation on the point cloud data after positioning is completed, delete redundant point cloud data that is not for the detected object, and retain the required point cloud data; S202. Perform point cloud filtering processing, filtering out nonlinear noise points while ensuring data stability using median filtering. Specifically: Among them, the Indicates the median output, the The coordinate grayscale value, the Indicates median processing; S203. Perform mean filtering on the point cloud data after median filtering to reduce noise and make the point cloud data smoother. Specifically: Among them, the Represents the mean filter output, the Represents the number of points in the neighborhood, the Representing the neighborhood, the Represents the initial grayscale value; S204. Extract the filtered point cloud cross-sectional data, and establish a reference surface based on the extracted point cloud cross-sectional data type. Project the point cloud cross-sectional data onto the reference surface to complete the point cloud projection processing. Perform point cloud projection partitioning and Kriging interpolation on the same cross-section two or more times, compare and calculate the interpolation results of the same partition two or more times, and obtain the corresponding deformation amount. Then, take the average value of the deformation amount of each partition and output the result to obtain the deformation results of each region of the engineering rock mass.

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