A method and system for monitoring deformation of fire-affected buildings based on air-ground remote sensing networking

Abstract

The present invention provides a method and system for monitoring deformation of a fire-affected building based on air-ground remote sensing networking, comprising: obtaining radar images through a ground deformation monitoring radar A, a UAV deformation monitoring radar B, and a UAV deformation monitoring radar C; geocoding the remote sensing images obtained by each radar, mapping the image coordinates of the building structure target in the radar slant range-azimuth polar coordinate system to local space three-dimensional coordinates; and iteratively solving the target three-dimensional deformation component and deformation speed according to radar distributed networking monitoring. The present invention can perform high-precision monitoring of the three-dimensional deformation of the building structure target in the fire emergency rescue scene.

Description

Technical Field

[0001] The present invention belongs to the field of remote sensing deformation monitoring of fire-affected buildings, and particularly relates to a method and system for monitoring the deformation of fire-affected buildings based on air-ground remote sensing networking. Background Art

[0002] Fire-affected buildings face the current situation of fast fire spread speed, difficult personnel evacuation, prone to secondary disasters such as gas leakage and collapse, and lack of safety monitoring means. The collapse of fire-affected buildings is extremely likely to cause serious consequences such as mass casualties, huge economic losses, and social panic. During the fire fighting and rescue process, it not only poses a great threat to the lives of fire fighting and rescue personnel, but also brings great pressure to the decision-making and implementation at the fire rescue site.

[0003] It has been found in both experiments and on-site fire observations that the change trends of the deformation displacement and deformation rate of building structure targets can reflect the essential characteristics of structure collapse. Therefore, the deformation of structure targets can be used as one of the main indicators for judging the collapse risk of buildings. Obtaining the three-dimensional deformation of key structure targets of fire-affected buildings in real time and accurately is of great significance for building collapse early warning at the fire site and ensuring the safety of rescue personnel.

[0004] However, although traditional deformation monitoring equipment combined with an Internet of Things monitoring platform can conduct normal monitoring and early warning of safety risks such as building settlement, inclination, cracks, and vibration, it is not suitable for deployment in fire rescue scenarios. Laser displacement monitoring equipment has the advantages of high precision and long detection distance. Although it has integrated functions such as infrared temperature measurement, inclination angle, and wireless transmission, it is still "single-point detection" and is easily affected by strong natural light or thermal radiation attenuation and environmental interference such as thick fog and thick smoke. Ground-based interferometric radar has the principle advantages of non-contact, large range, and high precision, and has been effectively applied in the measurement of deformation displacement of actual fire site structure targets in recent years. However, ground-based interferometric radar is limited by the monitoring perspective and cannot obtain the deformation information of key points at the top. Moreover, finding a temporary high point for erection affects the rescue efficiency. On the other hand, the single-radar monitoring method can only obtain the displacement result in the radar line-of-sight direction and cannot perceive the three-dimensional spatial deformation situation of the burning building, which affects the effectiveness and reliability of collapse early warning.

[0005] In summary, the existing technologies cannot meet the real-time and accurate monitoring requirements of the three-dimensional deformation of key structure targets of fire-affected buildings in fire rescue scenarios, and there is an urgent need for a new monitoring method and system to solve this problem. Summary of the Invention

[0006] The purpose of the present invention is to propose a method and system for monitoring the deformation of fire-affected buildings based on air-ground remote sensing networking for the three-dimensional deformation monitoring requirements of the top structure targets of buildings at the fire rescue site.

[0007] The technical solution of the present invention is as follows:

[0008] A method for monitoring the deformation of a fire-affected building by an air-ground remote sensing network, characterized by comprising the following steps:

[0009] Obtain radar images through the ground deformation monitoring radar A, the UAV deformation monitoring radar B, and the UAV deformation monitoring radar C;

[0010] Geocode the remote sensing images obtained by each radar, and map the two-dimensional image coordinates of the building structure target in the radar slant range-azimuth polar coordinate system to the three-dimensional coordinates in the local space;

[0011] Iteratively solve the three-dimensional deformation components and deformation velocities of the target based on the radar distributed network monitoring;

[0012] The deployment position of the UAV deformation monitoring radar C is determined by the following method:

[0013] First, according to the right-hand rule of the coordinate system and the direction vector, combined with the deployed positions of the ground deformation monitoring radar A and the UAV deformation monitoring radar B, preliminarily determine the candidate points for the UAV deformation monitoring radar C;

[0014] Adjust the flight pose in the area near the candidate points. During the adjustment process, calculate the condition number of the three-dimensional transformation matrix M in real time, and evaluate the stability of the transformation matrix M according to the condition number. When the transformation matrix M is invertible, determine this position as the final deployment position of the UAV deformation monitoring radar C;

[0015] The specific method for calculating the condition number of the three-dimensional transformation matrix M is as follows:

[0016] ,

[0017] where is the inverse matrix of the three-dimensional transformation matrix M .

[0018] Furthermore, the UAV deformation monitoring radar B is deployed at a position parallel to the vertical direction of the fire-affected building structure target.

[0019] Furthermore, the calculation formula for the deformation velocity is:

[0020] ,

[0021] where is the three-dimensional deformation velocity of the building structure target, is the position of the building structure after deformation, is the initial position of the building structure, t is the radar monitoring sampling period.

[0022] The present invention also provides a deformation monitoring system for a fire-affected building based on air-ground remote sensing networking, including a ground deformation monitoring radar A, an unmanned aerial vehicle (UAV) deformation monitoring radar B, and an unmanned aerial vehicle (UAV) deformation monitoring radar C; the ground deformation monitoring radar A is composed of a displacement monitoring module, an auxiliary function module, an infrared thermal imaging module, an intelligent control platform, and a power supply module; the unmanned aerial vehicle (UAV) deformation monitoring radar B and the unmanned aerial vehicle (UAV) deformation monitoring radar C are composed of a displacement monitoring module, an auxiliary function module, and a power supply module.

[0023] Further, the displacement monitoring module includes a fully solid-state radio frequency transceiver sub-module, a high-speed data acquisition and processing sub-module, and an MCU control sub-module. The fully solid-state radio frequency transceiver sub-module is used for transmitting and receiving frequency-modulated continuous-wave radio frequency signals. The high-speed data acquisition and processing sub-module is used for analog-to-digital sampling of the target echo complex signal. The MCU control sub-module is used for sending control commands and receiving information from each module.

[0024] The auxiliary function module includes a view acquisition sub-module, a pose monitoring sub-module, and a wireless transmission sub-module. The pose monitoring sub-module uses the Beidou satellite navigation system for positioning. The wireless transmission sub-module is used for sending the monitoring data to the intelligent control platform. The pose monitoring sub-module is used for;

[0025] The intelligent control platform is used for sending clock synchronization signals, receiving in real-time the monitoring data of the radar displacement monitoring module and the auxiliary function module, and iteratively optimizing the three-dimensional transformation matrix based on the radar pose data to complete the three-dimensional deformation decomposition of the building structure target.

[0026] The infrared thermal imaging module is used for real-time monitoring of the temperature distribution of the fire-affected building, and presenting the temperature differences of different parts of the building through thermal imaging technology.

[0027] Further, the power supply module is used for supplying power to each module of the ground deformation monitoring radar A, the unmanned aerial vehicle (UAV) deformation monitoring radar B, and the unmanned aerial vehicle (UAV) deformation monitoring radar C.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] First, it adopts a networking method that combines the ground deformation monitoring radar A with the UAV deformation monitoring radars B and C, achieving all-round and multi-angle monitoring of the fire-affected building. It not only utilizes the stability of the ground radar but also gives full play to the mobility and flexibility of the UAV radars, overcoming the single-point detection limitation of traditional monitoring equipment. Secondly, the three-dimensional deformation processing method in the system can accurately calculate the three-dimensional deformation components in the local space coordinate system and calculate the three-dimensional deformation velocity based on the measurement data of the radar through precise formulas and iterative algorithms, providing quantitative and accurate data for evaluating the deformation state of the building structure. Furthermore, by controlling the line-of-sight direction of the UAV deformation monitoring radar B to be approximately parallel to the Z-axis of the space coordinate system, it ensures the accurate acquisition of the deformation information of the building structure target in the vertical direction. For the deployment position of the UAV deformation monitoring radar C, through a unique determination method, that is, based on the right-hand rule of the coordinate system and the direction vector, the candidate points are initially determined in combination with the positions of the already deployed radars, and the flight pose is adjusted in the adjacent area. At the same time, according to the condition number of the three-dimensional transformation matrix M its stability is evaluated to ensure that the matrix is invertible, thus ensuring the scientificity and reliability of the monitoring points and improving the accuracy of the monitoring results. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings generally illustrate various embodiments by way of example and not limitation, and are used together with the description and the claims to illustrate the embodiments of the invention. Where appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be an exhaustive or exclusive embodiment of the device or method.

[0031] Figure 1 shows the schematic diagram of the air-ground remote sensing networking monitoring of the present invention;

[0032] Figure 2 shows the schematic diagram of the monitoring system of the present invention;

[0033] Figure 3 shows the schematic diagram of the three-dimensional deformation processing flow of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0035] As Figure 1 - Figure 2As shown in the figure, an embodiment of the present invention provides a deformation monitoring system for a fire-affected building based on air-ground remote sensing networking, including a ground deformation monitoring radar A, an unmanned aerial vehicle (UAV) deformation monitoring radar B, and an unmanned aerial vehicle (UAV) deformation monitoring radar C; the ground deformation monitoring radar A is composed of a displacement monitoring module, an auxiliary function module, an infrared thermal imaging module, an intelligent control platform, and a power supply module; the unmanned aerial vehicle (UAV) deformation monitoring radar B and the unmanned aerial vehicle (UAV) deformation monitoring radar C are composed of a displacement monitoring module, an auxiliary function module, and a power supply module.

[0036] The displacement monitoring module includes a fully solid-state radio frequency transceiver sub-module, a high-speed data acquisition and processing sub-module, and an MCU control sub-module. The fully solid-state radio frequency transceiver sub-module is used for transmitting and receiving frequency-modulated continuous-wave radio frequency signals. The high-speed data acquisition and processing sub-module is used for analog-to-digital sampling of the target echo complex signal. The MCU control sub-module is used for sending control instructions and receiving information from each module.

[0037] The auxiliary function module includes a view acquisition sub-module, a pose monitoring sub-module, and a wireless transmission sub-module. The pose monitoring sub-module uses the Beidou satellite navigation system for positioning. The wireless transmission sub-module is used for sending the monitoring data to the intelligent control platform. The pose monitoring sub-module is used for;

[0038] The intelligent control platform is used for sending clock synchronization signals, receiving the monitoring data of the radar displacement monitoring module and the auxiliary function module in real time, and iteratively optimizing the three-dimensional transformation matrix based on the radar pose data to complete the three-dimensional deformation decomposition of the building structure target.

[0039] The infrared thermal imaging module is used for real-time monitoring of the temperature distribution of the fire-affected building, and presenting the temperature differences of different parts of the building through thermal imaging technology.

[0040] The power supply module is used for supplying power to each module of the ground deformation monitoring radar A, the unmanned aerial vehicle (UAV) deformation monitoring radar B, and the unmanned aerial vehicle (UAV) deformation monitoring radar C.

[0041] On the other hand, the present invention also provides a three-dimensional deformation processing method for a fire-affected building based on air-ground remote sensing networking:

[0042] In the first step, let the equivalent phase center coordinates of the ground deformation monitoring radar A, the unmanned aerial vehicle (UAV) deformation monitoring radar B, and the unmanned aerial vehicle (UAV) deformation monitoring radar C be , and , where each coordinate value is the measurement result of a total station (or the measurement result of a three-dimensional laser scanner), and is expressed as follows

[0043] (1)

[0044] Let the The starting vector of the coordinate of the key structural target point of a building is , and its coordinate value is the measurement result of a total station or a 3D laser scanner), which is expressed as:

[0045] (2)

[0046] Second, the measured values of three deformation monitoring radars are respectively 、 、 , solve , satisfying the following system of equations

[0047] (3)

[0048] Let the ternary function 、 and be can be expressed as

[0049] (4)

[0050] Then there is

[0051] (5)

[0052] Third, assume that the target displacement between two adjacent measurements is small, that is is a small quantity, then the ternary function can be Taylor-expanded at , retaining the first-order term and ignoring the higher-order infinitesimals. At the same time, let the three constants 、 、 be respectively:

[0053] (6)

[0054] Then the system of equations to be solved is represented by a matrix as

[0055] (7)

[0056] Fourth, let , and let the matrix composed of the first-order Taylor expansion values at be M , there is

[0057] (8)

[0058] Then, using the coordinates of the three radars, the coordinates of the target point, and the three displacement measurements, the new position of the moved target can be obtained as:

[0059] (9)

[0060] Among them, is the starting vector of the coordinates of the key structural target points of the building, d is the measured value of the monitoring radar, M is the three-dimensional transformation matrix.

[0061] As Figure 3 shown, the present invention provides a method for monitoring the deformation of a building on fire by air-ground remote sensing networking, including the following steps:

[0062] In the first step, after the fire rescue team arrives at the building fire scene, the ground deformation monitoring radar A is first deployed;

[0063] In the second step, the UAV deformation monitoring radar B is made to fly above the structural target of the building on fire, so that its line-of-sight monitoring direction is approximately parallel to the Z-axis of the space coordinate system;

[0064] In the third step, according to the air-ground remote sensing networking principle, the UAV deformation monitoring radar C is dispatched to fly to the monitoring point, and the relevant principles are described as follows:

[0065] According to the right-hand rule of the coordinate system and the direction vector, the monitoring point of the UAV deformation monitoring radar C is initially determined. However, limited by the actual monitoring conditions at the fire scene, the monitoring range of the UAV deformation monitoring radar C may be difficult to cover the main structural targets on the top of the building.

[0066] In order to decompose the three-dimensional deformation components of the building structure target, the new constraint condition that must be ensured is that the three-dimensional transformation matrix M is invertible. The invertible matrix M condition number is used to describe the sensitivity of the linear system to error perturbations, so as to measure the stability of the linear system. If the condition number of the matrix is large, even a small change in the variables of the linear system will bring a drastic change to the solution of the linear system.

[0067] The pose is adjusted in the vicinity of the initially selected point, and the transformation matrix M is evaluated according to the condition number value, and finally the monitoring point of the UAV deformation monitoring radar C is determined.

[0068] In the fourth step, high-precision geocoding of the remote sensing image of the deformation monitoring radar is carried out, and the two-dimensional image coordinates of the building structure target in the radar slant range-azimuth polar coordinate system are mapped to the local space three-dimensional coordinates;

[0069] In the fifth step, the three-dimensional deformation components in the local coordinate system of the target are iteratively solved according to the relative position in space, and the three-dimensional deformation speed is calculated, that is:

[0070] (10)

[0071] Among them, is the target three-dimensional deformation speed of the building structure, is the position of the building structure after deformation, is the initial position of the building structure, t is the radar monitoring sampling period.

[0072] Finally, the result is uploaded to the monitoring and early warning cloud platform in real time.

[0073] As mentioned above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered within the protection scope of the present invention.

Claims

1. A method for monitoring deformation of a fire-affected building using an air-ground remote sensing network, characterized in that: The following steps are involved: The radar images are acquired through the ground deformation monitoring radar A, the UAV deformation monitoring radar B and the UAV deformation monitoring radar C; Geocoding the remote sensing images acquired by each radar, mapping the two-dimensional image coordinates of the building structure target in the radar slant range-azimuth polar coordinate system to three-dimensional coordinates in the local space; Iteratively calculate the target's three-dimensional deformation components and deformation speed based on radar distributed network monitoring; The deployment position of the UAV deformation monitoring radar C is determined by the following method: First, according to the right-hand rule of the coordinate system and Direction vector, combined with the deployed positions of ground-based deformation monitoring radar A and UAV deformation monitoring radar B, preliminarily determines the candidate position of UAV deformation monitoring radar C; The flight posture is adjusted in the vicinity of the candidate point. During the adjustment process, the three-dimensional transformation matrix is ​​calculated in real time. M The condition number of the transformation matrix M To evaluate the stability, when the transformation matrix M When reversibility is satisfied, the position is determined as the final deployment position of the UAV deformation monitoring radar C; The calculation of the three-dimensional transformation matrix M The condition number is specifically: ， in, is the three-dimensional transformation matrix M The inverse matrix of ， in, is the equivalent phase center coordinate of ground deformation monitoring radar A, is the equivalent phase center coordinate of the UAV deformation monitoring radar B, is the equivalent phase center coordinate of the UAV deformation monitoring radar C, is the starting vector of the coordinates of the Nth building key structure target point; is a constant; The UAV deformation monitoring radar B is arranged at a position parallel to the vertical direction of the fire-affected building structure target; The calculation formula of the deformation speed is: ， in, is the three-dimensional deformation speed of the building structure target, is the position of the building structure after deformation, is the initial position of the building structure, t It is the radar monitoring sampling period.

2. A fire-affected building deformation monitoring system based on air-ground remote sensing networking, using the fire-affected building deformation monitoring method based on air-ground remote sensing networking as claimed in claim 1, characterized in that: It includes a ground deformation monitoring radar A, a UAV deformation monitoring radar B and a UAV deformation monitoring radar C; the ground deformation monitoring radar A is composed of a displacement monitoring module, an auxiliary function module, an infrared thermal imaging module, an intelligent control platform, and a power supply module; the UAV deformation monitoring radar B and the UAV deformation monitoring radar C are composed of a displacement monitoring module, an auxiliary function module, and a power supply module.

3. The fire-affected building deformation monitoring system based on air-ground remote sensing networking according to claim 2 is characterized in that: The displacement monitoring module includes a full solid-state RF transceiver submodule, a high-speed data acquisition and processing submodule, and an MCU control submodule. The full solid-state RF transceiver submodule is used to transmit and receive frequency modulated continuous wave RF signals, the high-speed data acquisition and processing submodule is used for analog-to-digital sampling of target echo complex signals, and the MCU control submodule is used to send control instructions and receive information from various modules. The auxiliary function module includes a view acquisition submodule, a posture monitoring submodule, and a wireless transmission submodule. The posture monitoring submodule uses the Beidou satellite navigation system for positioning; the wireless transmission submodule is used to send monitoring data to the intelligent control platform; the posture monitoring submodule is used to; The intelligent control platform is used to send clock synchronization signals, receive monitoring data from the radar displacement monitoring module and the auxiliary function module in real time, and iteratively optimize the three-dimensional transformation matrix according to the radar posture data to complete the three-dimensional deformation decomposition of the building structure target; The infrared thermal imaging module is used to monitor the temperature distribution of the fire-affected building in real time, and present the temperature differences of different parts of the building through thermal imaging technology.

4. The fire-affected building deformation monitoring system based on air-ground remote sensing networking according to claim 2 is characterized in that: The power supply module is used to provide power supply for the ground deformation monitoring radar A, the UAV deformation monitoring radar B and the UAV deformation monitoring radar C.

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