Method for monitoring camera arrangement on construction site based on BIM

Abstract

The application discloses a method for arranging monitoring cameras in a construction site based on BIM, which comprises the following steps: establishing unit monitoring BIMs of various monitoring cameras and site layout BIMs of the construction site respectively, arranging the unit monitoring BIMs on the site layout BIMs, merging all the unit monitoring BIMs into a monitoring entity model and converting the monitoring entity model into a curved surface contour model, determining actual monitoring areas of the unit monitoring BIMs on the site layout BIMs according to the curved surface contour model and the site layout BIMs in a non-perspectiveness state, adjusting arrangement positions and / or quantities of the unit monitoring BIMs on the site layout BIMs when there are overlapping monitoring ranges in the actual monitoring areas, and arranging the unit monitoring BIMs on the site layout BIMs as an arrangement scheme of the monitoring cameras in the construction site until the unit monitoring BIMs arranged on the site layout BIMs with the least overlapping monitoring range are used as the arrangement scheme of the monitoring cameras in the construction site. The application can reduce the overlapping monitoring range, the quantity of the monitoring cameras and other monitoring devices, and the monitoring cost.

Description

Technical Field

[0001] This invention relates to the field of building engineering technology, and in particular to a method for deploying surveillance cameras on a construction site based on BIM. Background Technology

[0002] The monitoring facilities installed in construction projects include monitoring equipment and cables such as monitors, displays, storage devices, poles, and wires. As the construction scope of the construction site continues to expand, the number of monitoring cameras deployed on the construction site is increasing, and the monitoring equipment and cables such as monitors, displays, storage devices, poles, and wires may also increase as a result. This not only increases the cost of monitoring facilities on the construction site, but also leads to more and more areas being covered by overlapping monitoring ranges, resulting in waste. Summary of the Invention

[0003] The purpose of this invention is to provide a method for deploying surveillance cameras on construction sites based on BIM, in order to solve the problem of how to scientifically and rationally deploy surveillance cameras on construction sites to reduce monitoring costs and avoid waste caused by repeated coverage of the monitoring field of view.

[0004] To address the aforementioned technical problems, this invention provides a method for deploying surveillance cameras on a construction site based on BIM, comprising:

[0005] Step S1: Establish unit monitoring BIM for various surveillance cameras within the three-dimensional field of view;

[0006] Step S2: Create a site layout BIM for the construction site;

[0007] Step S3: Arrange unit monitoring BIM on the site layout BIM, and use the center point of the unit monitoring BIM as the control point.

[0008] Step S4: Merge all unit monitoring BIMs arranged on the site layout BIM into a single monitoring entity model through Boolean operations.

[0009] Step S5: Extract the outline and control points of the monitoring entity model, and convert the monitoring entity model into a curved surface outline model containing the control points.

[0010] Step S6: Set the site layout BIM to an opaque state. Determine the actual monitoring area of ​​each unit monitoring BIM on the site layout BIM by radially scattering projection, starting from each control point in the curved contour model and ending at the set of the contour boundary of the curved contour model and the surface of the site layout BIM in an opaque state.

[0011] Step S7: When the actual monitoring areas of the unit monitoring BIMs arranged on the site layout BIM overlap, adjust the arrangement position and / or number of unit monitoring BIMs on the site layout BIM.

[0012] Step S8, repeat steps S3 to S7 until the unit monitoring BIM with the least overlapping monitoring range is arranged on the site layout BIM as the arrangement scheme of the construction site monitoring cameras.

[0013] Step S9: Deploy surveillance cameras at the construction site according to the deployment plan for the surveillance cameras at the construction site.

[0014] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by the present invention determines the three-dimensional field of view of various surveillance cameras according to their horizontal field of view, vertical field of view, diagonal field of view, viewing distance, and rotation angle.

[0015] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by this invention calculates the horizontal field of view, vertical field of view, and diagonal field of view of various surveillance cameras according to their focal length, imaging width, and height.

[0016] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by this invention calculates the horizontal field of view according to the following formula:

[0017]

[0018] Where HFov is the horizontal field of view, W is the imaging width of the surveillance camera, and f is the focal length of the surveillance camera.

[0019] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by this invention calculates the vertical field of view according to the following formula:

[0020]

[0021] Where VFov is the vertical field of view, H is the imaging height of the surveillance camera, and f is the focal length of the surveillance camera.

[0022] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by this invention calculates the diagonal field of view according to the following formula:

[0023]

[0024] Where DFov is the diagonal field of view, W is the imaging width of the surveillance camera, H is the imaging height of the surveillance camera, and f is the focal length of the surveillance camera.

[0025] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by this invention determines the pixel size of human body imaging according to the Johnson criterion, and calculates the viewing distance of various surveillance cameras by combining the focal length of various surveillance cameras and the size of each effective pixel.

[0026] Furthermore, the method for deploying surveillance cameras on a construction site based on BIM provided by the present invention, in step 2, includes the following method for determining the three-dimensional field of view of various surveillance cameras:

[0027] The unidirectional three-dimensional field of view of various surveillance cameras is determined based on their horizontal, vertical, and diagonal field of view and viewing distance.

[0028] Based on the rotation angle of various surveillance cameras, determine the omnidirectional three-dimensional field of view of each type of surveillance camera.

[0029] Furthermore, the method for deploying monitoring cameras on a construction site based on BIM provided by the present invention adjusts the placement position and / or number of unit monitoring BIMs on the site layout BIM when the actual monitoring area of ​​the unit monitoring BIM deployed on the site layout BIM cannot cover the global monitoring range of the site layout BIM.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] This invention provides a method for deploying surveillance cameras on construction sites based on BIM. This method involves creating separate unit monitoring BIMs for various types of surveillance cameras and a site layout BIM for the construction site. The unit monitoring BIMs are then placed on the site layout BIM. All unit monitoring BIMs are merged into a single monitoring entity model and converted into a curved surface contour model. Based on the control points, contour boundaries, and the surface of the site layout BIM (which is not transparent) within the curved surface contour model, the actual monitoring area of ​​each unit monitoring BIM on the site layout BIM is determined. When overlapping monitoring areas exist, the placement and / or number of unit monitoring BIMs on the site layout BIM are adjusted until the unit monitoring BIMs with the least overlapping monitoring area are used as the deployment scheme for the surveillance cameras on the construction site. Compared with existing technologies, this method reduces overlapping monitoring areas, thereby reducing the number of surveillance cameras and other monitoring equipment required and lowering monitoring costs.

[0032] The present invention provides a method for deploying surveillance cameras on construction sites based on BIM. By reducing the overlapping monitoring range of unit monitoring BIM on site layout BIM, the method scientifically and rationally optimizes and guides the deployment of surveillance cameras on construction sites, avoiding the waste caused by repeated coverage of the monitoring field of view. Detailed Implementation

[0033] The present invention will now be described in detail: the advantages and features of the present invention will become clearer from the following description.

[0034] This invention provides a method for deploying surveillance cameras on a construction site based on BIM, which may include:

[0035] Step S1: Establish unit monitoring BIM (Building Information Modeling) for various surveillance cameras within their three-dimensional field of view. To determine the three-dimensional field of view of various surveillance cameras, the three-dimensional field of view of each surveillance camera can be determined based on its horizontal field of view, vertical field of view, diagonal field of view, viewing distance, and rotation angle.

[0036] Specifically, this may include:

[0037] Step S1.1: Calculate the horizontal field of view HFov, vertical field of view VFov, and diagonal field of view DFov of various types of surveillance cameras based on their focal length f, imaging width W, and imaging height H.

[0038] The horizontal field of view is calculated according to the following formula (1):

[0039]

[0040] The vertical field of view is calculated according to the following formula (2):

[0041]

[0042] The diagonal field of view is calculated according to the following formula (3):

[0043]

[0044] Step S1.2: Determine the pixel size of the human body image according to Johnson's criterion, and calculate the viewing distance of various surveillance cameras by combining the focal length f of various surveillance cameras and the size of each effective pixel.

[0045] Step S1.3: Determine the unidirectional three-dimensional field of view of various surveillance cameras based on their horizontal field of view, vertical field of view, diagonal field of view, and viewing distance.

[0046] Step S1.4: Determine the omnidirectional three-dimensional field of view of each type of surveillance camera based on the rotation angle of the various surveillance cameras.

[0047] Step S2: Create a site layout BIM for the construction site.

[0048] Step S3: Arrange the unit monitoring BIM on the site layout BIM, and use the center point of the unit monitoring BIM as the control point.

[0049] Step S4: Merge all the unit monitoring BIMs arranged on the site layout BIM into a single monitoring entity model through Boolean operations.

[0050] Step S5: Extract the outline and control points of the monitoring entity model, and convert the monitoring entity model into a curved surface outline model containing the control points.

[0051] Step S6: Set the site layout BIM to an opaque state. Using each control point in the curved contour model as the starting point and the set of the contour boundary of the curved contour model and the surface of the site layout BIM in an opaque state as the endpoint, determine the actual monitoring area of ​​each unit monitoring BIM on the site layout BIM by radial dispersion projection.

[0052] Step S7: When the actual monitoring areas of the unit monitoring BIMs arranged on the site layout BIM overlap, adjust the arrangement position and / or number of unit monitoring BIMs on the site layout BIM to reduce the overlapping monitoring range, i.e., reduce the overlap rate of the monitoring area. The overlap rate can be calculated based on the ratio of the projected overlapping area to the total area.

[0053] Step S8: Repeat steps S3 to S7 until the unit monitoring BIM with the least overlapping monitoring range is arranged on the site layout BIM as the arrangement scheme of the construction site monitoring cameras.

[0054] Step S9: Deploy surveillance cameras at the construction site according to the deployment plan for the surveillance cameras at the construction site.

[0055] The method for deploying surveillance cameras on construction sites based on BIM provided in this invention involves creating separate unit monitoring BIMs for various types of surveillance cameras and a site layout BIM for the construction site. The unit monitoring BIMs are then placed on the site layout BIM. All unit monitoring BIMs are merged into a single monitoring entity model and converted into a curved surface contour model. The actual monitoring area of ​​each unit monitoring BIM on the site layout BIM is determined based on the control points, contour boundaries, and the surface of the site layout BIM (which is not transparent). When overlapping monitoring areas exist, the placement position and / or number of unit monitoring BIMs on the site layout BIM are adjusted until the unit monitoring BIMs with the least overlapping monitoring area are placed on the site layout BIM. This is then used as the deployment scheme for the surveillance cameras on the construction site. Compared with existing technologies, this method reduces overlapping monitoring areas, thereby reducing the number of surveillance cameras and other monitoring equipment required and lowering monitoring costs.

[0056] The method for deploying surveillance cameras on a construction site based on BIM provided in this invention optimizes and guides the deployment of surveillance cameras on the construction site in a scientific and reasonable manner by reducing the overlapping monitoring range of the unit monitoring BIM on the site layout BIM, thus avoiding the waste caused by repeated coverage of the monitoring field of view.

[0057] To avoid monitoring blind spots, the method for deploying monitoring cameras on the construction site based on BIM provided in this embodiment of the invention adjusts the placement position and / or number of unit monitoring BIMs on the site layout BIM when the actual monitoring area of ​​the unit monitoring BIM deployed on the site layout BIM cannot cover the global monitoring range of the site layout BIM.

[0058] The method for deploying surveillance cameras on a construction site based on BIM provided in this invention improves the accuracy of camera deployment and the utilization rate of each camera by modeling the three-dimensional field of view of various surveillance cameras (i.e., unit monitoring BIM) and the three-dimensional model of the construction site (i.e., site layout BIM). This allows for a three-dimensional field of view diagram of the unit monitoring BIM layout on the site layout BIM, thereby avoiding the problem of excessive overlap in the monitoring range of conventional surveillance camera deployment schemes on construction sites, which prevents the effective utilization of the maximum utilization rate of various surveillance cameras.

[0059] This invention is not limited to the specific embodiments described above. Obviously, the embodiments described above are only a part of the embodiments of this invention, not all of them. All other embodiments obtained by those skilled in the art based on the described embodiments of this invention are within the scope of protection of this invention. Those skilled in the art can make other modifications and variations to this invention. Therefore, if these modifications and variations of this invention fall within the scope of the claims of this invention, then this invention also intends to include these modifications and variations.

Claims

1. A method for deploying surveillance cameras on a construction site based on BIM, characterized in that, include: Step S1: Establish unit monitoring BIM for various surveillance cameras within the three-dimensional field of view; Step S2: Create a site layout BIM for the construction site; Step S3: Arrange unit monitoring BIM on the site layout BIM, and use the center point of the unit monitoring BIM as the control point. Step S4: Merge all unit monitoring BIMs arranged on the site layout BIM into a single monitoring entity model through Boolean operations. Step S5: Extract the outline and control points of the monitoring entity model, and convert the monitoring entity model into a curved surface outline model containing the control points. Step S6: Set the site layout BIM to an opaque state. Determine the actual monitoring area of ​​each unit monitoring BIM on the site layout BIM by radially scattering projection, starting from each control point in the curved contour model and ending at the set of the contour boundary of the curved contour model and the surface of the site layout BIM in an opaque state. Step S7: When the actual monitoring areas of the unit monitoring BIMs arranged on the site layout BIM overlap, adjust the arrangement position and / or number of unit monitoring BIMs on the site layout BIM. Step S8, repeat steps S3 to S7 until the unit monitoring BIM with the least overlapping monitoring range is arranged on the site layout BIM as the arrangement scheme of the construction site monitoring cameras. Step S9: Deploy surveillance cameras at the construction site according to the deployment plan for the surveillance cameras at the construction site.

2. The method for deploying surveillance cameras on a construction site based on BIM according to claim 1, characterized in that, Based on the horizontal field of view, vertical field of view, diagonal field of view, viewing distance, and rotation angle of various surveillance cameras, the three-dimensional field of view range of various surveillance cameras is determined.

3. The method for deploying surveillance cameras on a construction site based on BIM according to claim 2, characterized in that, Based on the focal length, imaging width, and height of various surveillance cameras, calculate the horizontal field of view, vertical field of view, and diagonal field of view of each type of surveillance camera.

4. The method for deploying surveillance cameras on a construction site based on BIM according to claim 3, characterized in that, Calculate the horizontal field of view using the following formula: Where HFov is the horizontal field of view, W is the imaging width of the surveillance camera, and f is the focal length of the surveillance camera.

5. The method for deploying surveillance cameras on a construction site based on BIM according to claim 3, characterized in that, Calculate the vertical field of view using the following formula: Where VFov is the vertical field of view, H is the imaging height of the surveillance camera, and f is the focal length of the surveillance camera.

6. The method for deploying surveillance cameras on a construction site based on BIM according to claim 3, characterized in that, Calculate the diagonal field of view using the following formula: Where DFov is the diagonal field of view, W is the imaging width of the surveillance camera, H is the imaging height of the surveillance camera, and f is the focal length of the surveillance camera.

7. The method for deploying surveillance cameras on a construction site based on BIM according to claim 2, characterized in that, Based on the Johnson criterion, the pixel size of human body imaging is determined, and the viewing distance of various surveillance cameras is calculated by combining the focal length of various surveillance cameras and the size of each effective pixel.

8. The method for deploying surveillance cameras on a construction site based on BIM according to claim 1, characterized in that, In step S2, the method for determining the three-dimensional field of view of various surveillance cameras includes: The unidirectional three-dimensional field of view of various surveillance cameras is determined based on their horizontal, vertical, and diagonal field of view and viewing distance. Based on the rotation angle of various surveillance cameras, determine the omnidirectional three-dimensional field of view of each type of surveillance camera.

9. The method for deploying surveillance cameras on a construction site based on BIM according to claim 1, characterized in that, Step S7 also includes: When the actual monitoring area of ​​the unit monitoring BIM deployed on the site layout BIM cannot cover the global monitoring range of the site layout BIM, adjust the placement and / or number of unit monitoring BIMs on the site layout BIM.

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