Existing bridge BIM (Building Information Modeling) point cloud generation system and method based on oblique photography technology

Abstract

The invention discloses an existing bridge BIM (Building Information Modeling) point cloud generation system and method based on an oblique photography technology. The system comprises a flight device used for carrying a shooting and scanning device; the remote control device is used for controlling the flight device; the shooting and scanning device is used for acquiring target bridge data information; the data storage and transmission device is used for transmitting the target bridge data information; and the data terminal processing device is used for processing the target bridge data information to obtain point cloud data information and generating a target bridge BIM model based on the point cloud data information. According to the method, the bridge detection modeling efficiency and accuracy are greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge detection and modeling, and in particular to a system and method for generating a point cloud of a BIM model of an existing bridge based on oblique photography technology. Background Art

[0002] At present, the existing bridge model scanning and generation mainly rely on manual handheld equipment, drone scanning, etc. to obtain the corresponding information, and then convert it into a three-dimensional model. Not only is the process cumbersome and the accuracy is not high, but the internal steel bar information cannot be obtained. If a clearer and more practical BIM model is to be generated, the internal steel bar information must also be obtained. Therefore, a technology is needed that can more conveniently, quickly and accurately obtain the corresponding bridge data information and the bridge internal steel bar data information. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a system and method for generating point cloud of BIM model of existing bridges based on oblique photography technology, which can realize high-precision acquisition of bridge data and specific data of steel bars inside the bridge, greatly improving the efficiency and accuracy of bridge inspection modeling.

[0004] On the one hand, to achieve the above-mentioned purpose, the present invention provides a point cloud generation system for a BIM model of an existing bridge based on oblique photography technology, comprising:

[0005] Flying device: used to carry shooting and scanning devices;

[0006] Remote control device: used to control the flying device;

[0007] Photographing and scanning device: used to obtain data information of target bridge;

[0008] Data storage and transmission device: used for transmitting the target bridge data information;

[0009] Data terminal processing device: used for processing the target bridge data information, obtaining point cloud data information, and generating a target bridge BIM model based on the point cloud data information.

[0010] Preferably, the flying device comprises a GPS positioning module, and the GPS positioning module is used to locate the flying device and assist the photographing and scanning device in acquiring point cloud data information.

[0011] Preferably, the photographing and scanning device comprises:

[0012] Digital photography module: used to obtain detailed pictures of target bridges;

[0013] Laser scanner: used to obtain images of the target bridge at different angles;

[0014] Ground penetrating radar: used to obtain the location information of the steel bars inside the target bridge;

[0015] X-ray module: used to obtain the specific size information of the steel bars inside the target bridge;

[0016] Wherein, the digital photography module, the laser scanner, the ground penetrating radar and the X-ray module are all mounted on the flying device via a scanning platform bracket.

[0017] Preferably, the data storage and transmission device comprises:

[0018] Data storage module: used to store the information transmitted by the scanning and photographing device;

[0019] Wireless communication module: used to transmit the stored information to the data terminal processing device;

[0020] Wherein, the data storage module and the wireless communication module are both installed in the flying device.

[0021] Preferably, the remote control device is communicatively connected with the flying device to remotely control the flying device, the angle of the connecting piece, and the photographing and scanning device to achieve a preset flight route, flight altitude, and scanning angle.

[0022] On the other hand, to achieve the above-mentioned purpose, the present invention also provides a method for generating a point cloud of a BIM model of an existing bridge based on oblique photography technology, which is applied to a point cloud generation system of a BIM model of an existing bridge based on oblique photography technology, comprising:

[0023] The flying device is controlled by a remote control device to fly according to a set flight route, and a shooting and scanning device carried by the flying device is used to shoot a target bridge at multiple angles, directions and perspectives by an oblique photography method, and a steel structure of the target bridge is detected to obtain data information of the target bridge;

[0024] The target bridge data information is sent to a data terminal processing device through a data storage and transmission device for processing to generate a BIM model of the target bridge.

[0025] Preferably, the data terminal processing device performs processing including:

[0026] A coordinate system with the origin rod as the coordinate origin is constructed at the designated position of the target bridge, and the position coordinates of each corresponding point are obtained by subtracting the height coordinates calculated by the laser return time from the coordinates of the flying device relative to the coordinate origin, thereby obtaining point cloud data on the surface of several target bridges;

[0027] The position of the steel bars inside the target bridge is obtained based on the ground penetrating radar, and a three-dimensional visualization image is generated. The three-dimensional visualization image is scanned in combination with the X-ray module to obtain the size of the steel bars. The return signal information of each point is recorded based on the ground penetrating radar to obtain the position coordinates of the steel bars. The steel bar position coordinates are converted into coordinate points in three-dimensional space, and then the three-dimensional point cloud data of the steel bar position is obtained.

[0028] Preferably, generating the target bridge BIM model includes:

[0029] Based on the deep neural network model, feature extraction and denoising are performed on the point cloud data of the target bridge surface and the three-dimensional point cloud data of the steel bar position, and the data are adjusted into a unified format;

[0030] The data in unified format is input into the deep neural network model for classification and recognition to obtain the point cloud data of different components of the target bridge;

[0031] Modeling is performed based on the point cloud data of the different components to generate a BIM model of the target bridge.

[0032] Compared with the prior art, the present invention has the following advantages and technical effects:

[0033] The present invention uses a drone to drive a shooting and scanning device to shoot the target bridge in the air to obtain high-precision multi-view images of the bridge, and uses ground-penetrating radar and X-ray modules to scan the position and size of the steel bars, and store and transmit them, thereby achieving high-precision acquisition of bridge data and acquisition of specific data of the steel bars inside the bridge. In addition, the point cloud reverse modeling technology is used to quickly reconstruct the three-dimensional model of the object through professional modeling software such as BIM, greatly improving the efficiency and accuracy of bridge detection modeling. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0035] Figure 1 This is a flow chart of a method for generating a point cloud of an existing bridge BIM model based on oblique photography technology according to an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of a drone according to an embodiment of the present invention;

[0037] Figure 3 Schematic diagram of a coordinate unified rod according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0039] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0040] The present invention proposes a point cloud generation system for a BIM model of an existing bridge based on oblique photography technology, comprising:

[0041] Flying device: used to carry shooting and scanning devices;

[0042] Remote control device: used to control the flying device;

[0043] Photographing and scanning device: used to obtain data information of target bridge;

[0044] Data storage and transmission device: used for transmitting the target bridge data information;

[0045] Data terminal processing device: used for processing the target bridge data information, obtaining point cloud data information, and generating a target bridge BIM model based on the point cloud data information.

[0046] Furthermore, the flying device includes a GPS positioning module, which is used to locate the flying device and assist the shooting and scanning device in acquiring point cloud data information.

[0047] Furthermore, the photographing and scanning device comprises:

[0048] Digital photography module: used to obtain detailed pictures of target bridges;

[0049] Laser scanner: used to obtain images of the target bridge at different angles;

[0050] Ground penetrating radar: used to obtain the location information of the steel bars inside the target bridge;

[0051] X-ray module: used to obtain the specific size information of the steel bars inside the target bridge;

[0052] Wherein, the digital photography module, the laser scanner, the ground penetrating radar, and the X-ray module are all mounted on the flying device via a scanning platform bracket. Figure 2 .

[0053] Furthermore, the data storage and transmission device comprises:

[0054] Data storage module: used to store the information transmitted by the scanning and photographing device;

[0055] Wireless communication module: used to transmit the stored information to the data terminal processing device;

[0056] Among them, the data storage module and the wireless communication module are both installed in the flight device.

[0057] Furthermore, the remote control device is communicatively connected with the flying device, and can remotely control the flying device, the angle of the connecting piece, and the photographing and scanning device to achieve a preset flight route, flight altitude, and scanning angle.

[0058] This embodiment also provides a method for generating a point cloud of a BIM model of an existing bridge based on oblique photography technology, which is applied to a system for generating a point cloud of a BIM model of an existing bridge based on oblique photography technology. Figure 1 ,include:

[0059] The flying device is controlled by a remote control device to fly according to a set flight route, and a shooting and scanning device carried by the flying device is used to shoot a target bridge at multiple angles, directions and perspectives by an oblique photography method, and a steel structure of the target bridge is detected to obtain data information of the target bridge;

[0060] The target bridge data information is sent to a data terminal processing device through a data storage and transmission device for processing to generate a BIM model of the target bridge.

[0061] Specifically, during the inspection process, a reference system member (such as Figure 3 ) to unify the coordinates. Then, the tilt angle of the camera is remotely adjusted according to the specific conditions of the bridge to ensure the integrity and accuracy of the bridge shooting and the acquisition of bridge steel bar information by the ground penetrating radar.

[0062] The remote-controlled drone flies completely according to the established flight route. Based on the oblique photography technology, it shoots the bridge from multiple angles, directions and perspectives and detects steel bars, obtaining a large number of high-definition and high-precision bridge pictures. It also remotely controls the laser scanner and X-ray to scan the bridge in all directions with appropriate overlap to obtain relevant bridge data. Among them, the GPS positioning module locates and records the drone's flight information in real time, such as altitude, tilt angle, status, etc.

[0063] Furthermore, the data terminal processing device performs processing, including:

[0064] A coordinate system with the origin rod as the coordinate origin is constructed at the designated position of the target bridge, and the position coordinates of each corresponding point are obtained by subtracting the height coordinates calculated by the laser return time from the coordinates of the flying device relative to the coordinate origin, thereby obtaining point cloud data on the surface of several target bridges;

[0065] Specifically, for the bridge surface, the time and angle of laser return at each point obtained by the scanner are combined with the analysis of the photos taken by the camera and the positioning of the drone by GPS to establish a coordinate system with the origin rod as the origin of the coordinates. The position coordinates of each corresponding point are obtained by subtracting the height coordinates calculated by the laser return time from the coordinates of the drone relative to the origin of the coordinates, forming a series of point cloud data.

[0066] Furthermore, the position of the steel bars inside the target bridge is obtained based on the ground penetrating radar, a three-dimensional visualization image is generated, and the three-dimensional visualization image is scanned in combination with the X-ray module to obtain the size of the steel bars. The return signal information of each point is recorded based on the ground penetrating radar to obtain the position coordinates of the steel bars, and the steel bar position coordinates are converted into coordinate points in three-dimensional space, thereby obtaining three-dimensional point cloud data of the steel bar position.

[0067] Specifically, for the steel bars in the bridge, the ground penetrating radar emits electromagnetic pulses into the interior of the bridge and then measures them with X-ray perspective scanning. The ground penetrating radar receives different return signals through different material media, depths, lengths, etc. The processed data is converted into a visual image form, and the typical performance of steel bars in the GPR image is found by analyzing the hyperbolic features in the image. The signal of the steel bar can be determined, and the depth position of the target can be calculated by multiplying the speed by half of the return time through the time of the measured reflected signal recorded by the radar, combined with the propagation speed factor of the signal propagation medium, and the X-ray module is used to scan the interior of the bridge to generate a three-dimensional visual image to obtain the size of the steel bar. The ground penetrating radar will record the return signal information of each point, including time, intensity, etc., and through the GPS positioning module integrated in the drone, the position coordinates of the steel bar are obtained in the same way as the above-mentioned bridge surface scanning. The determined steel bar position is converted into a coordinate point in three-dimensional space, and these coordinate points are used to create a preliminary three-dimensional point cloud data with the origin bar as the coordinate origin to represent the distribution of the steel bar.

[0068] Furthermore, a target bridge BIM model is generated, including:

[0069] Based on the deep neural network model, feature extraction and denoising are performed on the point cloud data of the target bridge surface and the three-dimensional point cloud data of the steel bar position, and the data are adjusted into a unified format;

[0070] The data in unified format is input into the deep neural network model for classification and recognition to obtain the point cloud data of different components of the target bridge;

[0071] Modeling is performed based on the point cloud data of the different components to generate a BIM model of the target bridge.

[0072] Specifically, the processed point cloud data of the bridge and steel bars are converted into the same required format for storage using software (such as CloudCompare). Then, a deep neural network model is trained based on the existing network, and a large amount of bridge component point cloud data is used to feed the learning and classification of the characteristic points of the bridge components, so as to detect and mark the key building elements to identify the characteristic points, such as beams, bridge arches, bridge piers, etc. to distinguish different components. The processed point cloud data is input into the BIM modeling software that can recognize point cloud data (such as Graphisoft, etc.), and the corresponding geometric shapes and non-geometric attribute information are established according to the identified characteristic points, and the steel bar size information is added. After completing the preliminary modeling, compare the on-site photos, and further adjust and improve the model details if necessary. The operator can supplement and improve the model in the BIM software by comparing the on-site photos to verify the integrity of the model. If the comparison model is complete, the completed BIM model will be exported and uploaded to the designated BIM management platform through the data terminal platform.

[0073] The present invention uses a drone to drive a shooting and scanning device to shoot the target bridge in the air to obtain high-precision multi-view images of the bridge, and uses ground-penetrating radar and X-ray modules to scan the position and size of the steel bars, and store and transmit them, thereby achieving high-precision acquisition of bridge data and acquisition of specific data of the steel bars inside the bridge. In addition, the point cloud reverse modeling technology is used to quickly reconstruct the three-dimensional model of the object through professional modeling software such as BIM, greatly improving the efficiency and accuracy of bridge detection modeling.

[0074] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A point cloud generation system for BIM models of existing bridges based on oblique photography technology, characterized in that: include: Flying device: used to carry shooting and scanning devices; Remote control device: used to control the flying device; Photographing and scanning device: used to obtain data information of target bridge; Data storage and transmission device: used for transmitting the target bridge data information; Data terminal processing device: used for processing the target bridge data information, obtaining point cloud data information, and generating a target bridge BIM model based on the point cloud data information.

2. The existing bridge BIM model point cloud generation system based on oblique photography technology according to claim 1 is characterized in that: The flying device includes a GPS positioning module, which is used to locate the flying device and assist the shooting and scanning device in acquiring point cloud data information.

3. The existing bridge BIM model point cloud generation system based on oblique photography technology according to claim 1 is characterized in that: The photographing and scanning device comprises: Digital photography module: used to obtain detailed pictures of target bridges; Laser scanner: used to obtain images of the target bridge at different angles; Ground penetrating radar: used to obtain the location information of the steel bars inside the target bridge; X-ray module: used to obtain the specific size information of the steel bars inside the target bridge; Wherein, the digital photography module, the laser scanner, the ground penetrating radar and the X-ray module are all mounted on the flying device via a scanning platform bracket.

4. The existing bridge BIM model point cloud generation system based on oblique photography technology according to claim 3 is characterized in that: The data storage transmission device comprises: Data storage module: used to store the information transmitted by the scanning and photographing device; Wireless communication module: used to transmit the stored information to the data terminal processing device; Wherein, the data storage module and the wireless communication module are both installed in the flying device.

5. The existing bridge BIM model point cloud generation system based on oblique photography technology according to claim 1 is characterized in that: The remote control device is connected to the flying device for remotely controlling the flying device, the angle of the connecting piece, and the photographing and scanning device to achieve a preset flight route, flight altitude, and scanning angle.

6. A method for generating a point cloud of a BIM model of an existing bridge based on oblique photography technology, applied to a system for generating a point cloud of a BIM model of an existing bridge based on oblique photography technology as claimed in any one of claims 1 to 5, characterized in that: include: The flying device is controlled by a remote control device to fly according to a set flight route, and a shooting and scanning device carried by the flying device is used to shoot a target bridge at multiple angles, directions and perspectives by an oblique photography method, and a steel structure of the target bridge is detected to obtain data information of the target bridge; The target bridge data information is sent to a data terminal processing device through a data storage and transmission device for processing to generate a BIM model of the target bridge.

7. The method for generating point cloud of BIM model of existing bridge based on oblique photography technology according to claim 6 is characterized in that: The data terminal processing device performs processing, including: A coordinate system with the origin rod as the coordinate origin is constructed at the designated position of the target bridge, and the position coordinates of each corresponding point are obtained by subtracting the height coordinates calculated by the laser return time from the coordinates of the flying device relative to the coordinate origin, thereby obtaining point cloud data on the surface of several target bridges; The position of the steel bars inside the target bridge is obtained based on the ground penetrating radar, and a three-dimensional visualization image is generated. The three-dimensional visualization image is scanned in combination with the X-ray module to obtain the size of the steel bars. The return signal information of each point is recorded based on the ground penetrating radar to obtain the position coordinates of the steel bars. The steel bar position coordinates are converted into coordinate points in three-dimensional space, and then the three-dimensional point cloud data of the steel bar position is obtained.

8. The method for generating point cloud of BIM model of existing bridge based on oblique photography technology according to claim 7 is characterized in that: Generating the target bridge BIM model includes: Based on the deep neural network model, feature extraction and denoising are performed on the point cloud data of the target bridge surface and the three-dimensional point cloud data of the steel bar position, and the data are adjusted into a unified format; The data in unified format is input into the deep neural network model for classification and recognition to obtain the point cloud data of different components of the target bridge; Modeling is performed based on the point cloud data of the different components to generate a BIM model of the target bridge.

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