Power transmission line digital twin-driven unmanned aerial vehicle inspection virtual operation platform

Abstract

The invention relates to a digital twin-driven unmanned aerial vehicle inspection virtual operation platform for a power transmission line, which combines real calculation data of unmanned aerial vehicle flight control, a fine collision detection technology and physical rigid body operation of an unmanned aerial vehicle and a line to achieve optimal unmanned aerial vehicle training hand feeling and attitude simulation. The unmanned aerial vehicle control training system is used for satisfying professional training of unmanned aerial vehicle control in power transmission line inspection, improving related knowledge literacy and post operation level capability of trainees, and improving operation and maintenance current situations of power transmission lines.

Description

Technical Field

[0001] The present invention relates to the technical field of virtual operation of transmission line drone inspection, and in particular to a transmission line digital twin-driven drone inspection virtual operation platform. Background Art

[0002] Smart transmission lines use monitoring sensors, information communication, data fusion and other technologies to achieve panoramic data management, transparent operation status, intelligent diagnosis and decision-making, and have the characteristics of real-time perception, holographic interconnection, autonomous early warning, and intelligent disposal. The introduction of drone inspections in smart transmission lines greatly improves the reliability and operability of inspections. However, with the introduction of drone inspections, higher requirements are placed on operators. The training department needs to effectively improve the training model and training methods for operation and maintenance team members, so as to build an efficient smart line operation and maintenance model and cultivate high-precision smart transmission line operation and maintenance reserve talents. Therefore, a transmission line drone inspection virtual operation platform is needed to lay a solid foundation for creating a digital service assistant for front-line inspections, fully supporting the construction of digital teams, improving the effectiveness of power grid operation and maintenance, and ensuring the safe and stable operation of the power grid.

[0003] The existing virtual operation platform for transmission line drone inspection has a large difference in the proportion, size, structure and texture of the construction of virtual scenes and real objects. Unstructured data such as terrain, images, and point clouds in virtual scenes are stored and published in the form of files, which makes it difficult to establish spatial indexes, resulting in low data access efficiency. Redundant point cloud data far away from the field of view will be loaded synchronously, increasing the network load; the loading and rendering order of terrain and objects in different virtual scenes is unreasonable, and a large number of vegetation superiors to the loading of poles, towers, and lines, resulting in delayed display of important objects. The existing virtual operation platform is not sensitive to obstacle avoidance in drone motion control, and often collides with obstacles when controlling drones to inspect transmission lines. Some operation platforms cannot display the position of drones in the scene in real time through a small window, which makes it extremely difficult to operate drones to find suitable and effective transmission lines. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a transmission line digital twin driven drone inspection virtual operation platform, to improve the training personnel's relevant knowledge literacy and job operation level ability, and to improve the operation and maintenance status of the transmission line.

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical solutions: a transmission line digital twin-driven UAV inspection virtual operation platform, comprising: a transmission line virtual scene building module, a digital twin control module and a simulation platform interface design module;

[0006] The transmission line virtual scene building module includes a virtual scene model and a 3D drone model. The modeling process firstly takes the 3D data as the basis, uses the tower shape and various hardware equipment data information, integrates the transmission line terrain model, tower model and monitoring sensor equipment model, and then introduces 3Ds MAX software to realize the mapping rendering of the 3D model.

[0007] In the virtual scene, each model is composed of a number of triangular facets. The transmission line virtual scene building module includes an occlusion culling technology. The occlusion culling technology avoids the phenomenon of sudden changes in the model at the edge of the field of view by setting two culling distances.

[0008] The digital twin control module includes the UAV flight motion control module and the data interaction platform module;

[0009] The data interaction platform module includes a MySQL database, which is responsible for the storage of sensor data and the distribution of control data. The data interaction platform module is designed with two interfaces, namely the connection between the MySQL database and the data transmission end and the communication between the MySQL database and the virtual control platform. The connection with the data transmission end can realize the sensor data storage by calling the sensor dynamic link library, and the connection with the remote control platform is realized through the Unity3D platform.

[0010] The simulation platform interface design includes drone model selection module, mode selection module, perspective switching module and scene switching module.

[0011] In a preferred embodiment, in the virtual scene model, the camera field of view in the three-dimensional space is projected into the two-dimensional coordinates, and the field of view vector v is obtained by normalization calculation. → =(0,0,1), define the three coordinate points of a triangle as: A(x1,y1,z1), B(x2,y2,z2), C(x3,y3,z3), the normal vector of ΔABC for:

[0012]

[0013] Normal vector of ΔABC The projection in the direction of the camera's field of view is:

[0014]

[0015] The three-dimensional vector is converted into a two-dimensional coordinate for elimination calculation. At this time, the normal vector of ΔABC With the field of view vector The angle is expressed as:

[0016]

[0017] Determine the model triangular faces to be removed according to the included angle θ;

[0018] Set two culling thresholds Dmax and Dmin, and during the operation of the scene, the two culling distances monitor the distance d in real time:

[0019] When d > Dmax, the virtual scene model of the transmission line is outside the viewing range, and the virtual scene model of the transmission line in this range is completely removed;

[0020] When Dmin < d ≤ Dmax, the virtual scene model of the transmission line adjusts the transparency of the rendering material according to the viewing distance, so that the models at different positions present different material effects;

[0021] When d ≤ Dmin, the virtual scene model of the transmission line within the range presents a fine rendering effect;

[0022] 发射虚拟射线以无人机碰撞器为原点向机身周围发射虚拟射线,实现飞行过程中实时碰撞预警检测;无人机移动飞行过程中,虚拟射线和碰撞体模块启动,虚拟无人机在移动过程中向周围发射虚拟光线,监测机身与其他碰撞体之间的相对距离L;根据模拟飞行条件,设置虚拟无人机的碰撞预警阈值界限Lmax和Lmin;虚拟无人机起飞移动时,射线检测模块开始运行,虚拟交互界面监测窗口实时监控无人机与其他设备、环境模型间的相对距离L:Emit virtual rays. With the drone collider as the origin, emit virtual rays around the fuselage to achieve real-time collision warning detection during flight; during the movement of the drone, the virtual ray and collider modules are activated, and the virtual drone emits virtual light around during movement to monitor the relative distance L between the fuselage and other colliders; according to the simulated flight conditions, set the collision warning threshold limits Lmax and Lmin of the virtual drone; when the virtual drone takes off and moves, the ray detection module starts to run, and the virtual interaction interface monitoring window monitors the relative distance L between the drone and other devices and environmental models in real time:

[0023] When L > Lmax, the virtual drone moves normally and there is no collision threat;

[0024] When Lmax > L > Lmin, the distance L enters the warning stage, and the system issues a collision warning signal, prompting the trained personnel operating the drone that there may be a collision threat and the trained personnel need to adjust the flight attitude and movement trajectory;

[0025] When L < Lmin, the distance L enters the threat stage, and the drone may collide with the tower or other obstacles, and collision detection is required; if a collision is detected to have occurred, the drone immediately stops flying and maintains a hovering state; if no collision has occurred, re-plan the movement trajectory of the drone according to the obstacle information and adjust the flight path.

[0026] In a preferred embodiment, in the drone flight motion control module, the motion states of the quadrotor drone have four basic forms: vertical lifting motion, roll motion, pitch motion, and yaw motion; the rotor speeds of the quadrotor drone are expressed as:

[0027] ω i = ω0 + Δω i , i = 1, 2, 3, 4

[0028] Where ω0 represents the rotor speed during hovering, Δω i Indicates the adjustable amount on a hover basis;

[0029] The vertical lifting motion of the quad-rotor drone is achieved by changing the rotation speed of the four blades at the same time, and the rotation speed ω of the four rotors is the same, ensuring that the rotation speed of the four rotors remains consistent and the lift generated by the rotors is equal;

[0030]

[0031] In a preferred embodiment, the UAV flight motion control module also includes a UAV obstacle avoidance control strategy. During the movement of the UAV, a global navigation path is first planned based on the established initial transmission line model and the initialization target parameters, and the training personnel control the virtual UAV through the handle; when the sensor carried by the UAV collects obstacle information, it determines whether the relative distance between the UAV and the dynamic obstacle is less than the system collision warning limit value based on the set obstacle impact distance. If it enters the collision warning limit, the aircraft enters local avoidance; obstacle avoidance control is performed through the composite potential field VFF algorithm and an alarm is issued to the training personnel to ensure that the UAV safely passes the dynamic threat.

[0032] In a preferred embodiment, the connection between the MySQL database and the remote control platform is to call the stored sensor data on the one hand, and to save the control commands of the virtual control platform on the other hand; the specific steps of connecting to the database are as follows:

[0033] Step 1: Call the MySQL_init() function to allocate and initialize the MySQL database table that matches the connection;

[0034] Step 2: Call the MySQL_option() function to set the connection options and initialize the data structure;

[0035] Step 3: Call the MySQL_connect() function to connect to the database. After the connection is successful, write SQL language to implement update operations such as inserting and deleting data tables.

[0036] Step 4: After the operation is completed, call the MySQL_close() function to close the database.

[0037] In a preferred embodiment, the scene switching module sets the lighting effects in different time periods of morning, noon and afternoon according to the needs of the training personnel; the perspective switching module provides multi-perspective switching of drone perspective and gimbal perspective; the mode selection module provides training mode, assessment mode and defect recognition mode.

[0038] In a preferred embodiment, the simulation platform interface design also sets a navigation mini-map of corresponding scale according to the virtual model of the power transmission line, and displays the position of the virtual drone during the inspection in real time; the zoom ratio of the mini-map is:

[0039]

[0040] Synchronize the position of the virtual drone on the power line on the mini-map:

[0041] x′=X′·l x ,y′=Y′·l y

[0042] Among them, (x, y) represents the position of the UAV on the transmission line, (x′, y′) is the coordinate position of the UAV synchronized on the small map; the size of the tunnel model is (X, Y), and (X′, Y′) represents the size of the small map.

[0043] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a transmission line digital twin-driven UAV inspection virtual operation platform design, combining the real calculation data of the UAV flight control, fine collision detection technology, and the physical rigid body calculation of the UAV and the line to achieve the optimal UAV training feel and posture simulation. It is used to meet the professional training of UAV control in power transmission line inspections, improve the relevant knowledge literacy and job operation level of training personnel, and improve the current operation and maintenance status of transmission lines. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A schematic diagram of the virtual platform system structure design of a preferred embodiment of the present invention;

[0045] Figure 2 A collision warning monitoring flow chart of a preferred embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the rotation of the UAV rotor in a preferred embodiment of the present invention;

[0047] Figure 4 It is a flow chart of obstacle avoidance strategy control in a preferred embodiment of the present invention;

[0048] Figure 5 A schematic diagram of a data interaction platform design according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0049] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0050] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0052] The present invention designs a transmission line digital twin-driven UAV inspection virtual operation platform, such as Figure 1-5 As shown, the technical solution specifically includes:

[0053] Transmission line virtual scene building module, digital twin control module and simulation platform interface design module.

[0054] The transmission line virtual scene construction module includes a virtual scene model and a three-dimensional drone model. The modeling process is first based on three-dimensional data, using the tower shape and various hardware equipment data information, and using SolidWorks three-dimensional design software to integrate the transmission line terrain model, tower model, various hardware and monitoring sensor equipment models. Then, 3Ds MAX software is introduced to realize the mapping rendering of the three-dimensional model.

[0055] In the virtual scene, each model is composed of several triangular facets. The more triangular facets a model object has, the higher its complexity. Therefore, the transmission line virtual scene construction module includes occlusion culling technology. Occlusion culling technology means that when a model object is blocked by other objects and does not appear in the camera's field of view, it is culled and not rendered. The rendering of the model outside the field of view can be ignored, thereby improving the model rendering efficiency and reducing the time complexity of the model. Occlusion culling technology avoids the phenomenon of sudden changes in the model at the edge of the field of view by setting two culling distances. The camera field of view in three-dimensional space is projected into two-dimensional coordinates, and the field of view vector v is obtained by normalization calculation. → =(0,0,1), define the three coordinate points of a triangle as: A(x1,y1,z1), B(x2,y2,z2), C(x3,y3,z3), the normal vector of ΔABC for:

[0056]

[0057] Normal vector of ΔABC The projection in the direction of the camera's field of view is:

[0058]

[0059] The three-dimensional vector is transformed into a two-dimensional coordinate for culling calculation, reducing the complexity of system calculation. At this time, the normal vector of ΔABC and the field of view vector The included angle can be expressed as:

[0060]

[0061] Judge the model triangular faces to be culled according to the included angle θ.

[0062] Set two culling thresholds Dmax and Dmin. During the operation of the scene, the two culling distances monitor the distance d in real time:

[0063] When d > Dmax, the virtual scene model of the transmission line is outside the viewing range, and the virtual scene model of the transmission line in this range is completely culled;

[0064] When Dmin < d ≤ Dmax, the virtual scene model of the transmission line adjusts the transparency of the rendering material according to the size of the viewing distance, so that the models at different positions present different material effects;

[0065] When d ≤ Dmin, the virtual scene model of the transmission line within the range presents a fine rendering effect. The occlusion culling technology can achieve the fade-in and fade-out gradient effect of the virtual scene, making the visual effect more realistic while reducing the running memory.

[0066] In the construction of the virtual scene of the transmission line, the present invention adds relevant colliders to the virtual scene model and the three-dimensional unmanned aerial vehicle model to prevent the moving virtual unmanned aerial vehicle from passing through static buildings.

[0067] Taking the unmanned aerial vehicle collider as the origin, virtual rays are emitted around the fuselage to realize real-time collision warning detection during flight. As Figure 2 shown, during the movement and flight of the unmanned aerial vehicle, the virtual rays and the collision body module are activated. During the movement of the virtual unmanned aerial vehicle, virtual rays are emitted around to monitor the relative distance L between the fuselage and other collision bodies. According to the simulated flight conditions, set the collision warning threshold limits Lmax and Lmin of the virtual unmanned aerial vehicle. When the virtual unmanned aerial vehicle takes off and moves, the ray detection module starts to run, and the virtual interaction interface monitoring window monitors the relative distance L between the unmanned aerial vehicle and other devices and environmental models in real time:

[0068] When L > Lmax, the virtual unmanned aerial vehicle moves normally and there is no collision threat;

[0069] When Lmax > L > Lmin, the distance L enters the warning stage, and the system issues a collision warning signal, prompting the trained operator that the UAV may be at risk of collision and requiring the operator to adjust the flight attitude and trajectory;

[0070] When L < Lmin, the distance L enters the threat stage, and the UAV may collide with the tower or other obstacles, and collision detection is required. If a collision is detected, the UAV immediately stops flying and hovers; if no collision occurs, the UAV's motion trajectory is replanned based on the obstacle information to adjust the flight path.

[0071] The digital twin control module includes a UAV flight motion control module and a data interaction platform module.

[0072] As Figure 3 shown, taking the quadrotor UAV as an example, the motion states of the UAV flight motion control module mainly have four basic forms: vertical lifting motion, roll motion, pitch motion, and yaw motion. The quadrotor UAV can change the lift in the direction of the rotation axis by adjusting the rotational speeds of the four motors, so that it can fly in various postures and then control its own position and speed changes. The rotational speed of the rotor can be expressed as:

[0073] ω i =ω0 + Δω i , i = 1, 2, 3, 4

[0074] where ω0 represents the rotational speed of the rotor during hovering, and Δω i represents the adjustable amount based on hovering.

[0075] The vertical lifting motion of the quadrotor UAV is achieved by simultaneously changing the rotational speeds of the four blades, and the rotational speeds ω of the four rotors are the same to ensure that the rotational speeds of the four rotors are consistent and the lift generated by the rotors is equal.

[0076]

[0077] The pitch and roll motions of the quadrotor UAV are achieved by simultaneously increasing or decreasing the rotational speeds of the left and right groups of M2, M3 rotors or M1, M4 rotors. Using the lift generated by the rotation of the M2, M3 rotors and M1, M4 rotors, a moment difference around the X b axis of the body coordinate system is caused. This moment difference generates a corresponding angular acceleration to achieve the roll motion of the UAV. Along with the motion of the angular acceleration, there will be a sliding motion in the corresponding direction, that is, it will fly right when rolling right and fly left when rolling left. The yaw motion of the quadrotor UAV is achieved by simultaneously increasing or decreasing the rotation of the two diagonal groups of M1, M3 rotors and M2, M4 rotors. When the increase and decrease amounts are the same, the total lift is ensured to remain unchanged. Using the rotation of the rotors to generate a rotation around the Z axis of the body coordinate systemb The anti-torque difference of the axis generates a corresponding angular acceleration, thereby realizing the yaw motion of the drone.

[0078] like Figure 4 As shown, the design of the UAV flight motion control module of the present invention also includes a UAV obstacle avoidance control strategy. During the movement of the UAV, the global navigation path is first planned according to the established initial transmission line model and the initialization target parameters, and the training personnel control the virtual UAV through the handle. When the sensor carried by the UAV collects obstacle information, it is determined whether the relative distance between the UAV and the dynamic obstacle is less than the system collision warning limit value according to the set obstacle impact distance. If the collision warning limit is reached, the aircraft enters the local obstacle avoidance stage. In the local obstacle avoidance process, in order to avoid dynamic obstacles and establish local target points, the composite potential field VFF algorithm is used to perform obstacle avoidance control and issue an alarm to the training personnel to ensure that the UAV safely passes the dynamic threat.

[0079] like Figure 5 As shown, the data interaction platform module includes a MySQL database, which is mainly responsible for the storage of sensor data and the distribution of control data. The data interaction platform module is designed with two interfaces, namely the connection between the MySQL database and the data transmission end and the communication between the MySQL database and the virtual control platform. The connection with the data transmission end can realize sensor data storage by calling the sensor dynamic link library, and the connection with the remote control platform is realized through the Unity3D platform. The connection between the MySQL database and the remote control platform is to call the stored sensor data on the one hand, and to save the control commands of the virtual control platform on the other hand. The specific steps for connecting to the database are as follows:

[0080] Step 1: Call the MySQL_init() function to allocate and initialize the MySQL database table that matches the connection;

[0081] Step 2: Call the MySQL_option() function to set the connection options and initialize the data structure;

[0082] Step 3: Call the MySQL_connect() function to connect to the database. After the connection is successful, write SQL language to implement update operations such as inserting and deleting data tables.

[0083] Step 4: After the operation is completed, call the MySQL_close() function to close the database.

[0084] The simulation platform interface design includes modules such as drone model selection, mode selection, perspective switching, and scene switching.

[0085] The scene switching module can set the lighting effects for different time periods in the morning, noon and afternoon according to the needs of training personnel; the perspective switching module provides multiple perspective switching such as drone perspective and gimbal perspective.

[0086] In view of the learning ability of the trainees, the mode selection module of the present invention provides training mode, assessment mode and defect recognition mode. The training mode is mainly based on guidance, teaching the trainees how to control the virtual drone to patrol the line and take pictures. In the assessment mode, the platform provides patrol and photography assessment tasks at different levels for the trainees to operate, and provides an assessment settlement module to display the trainees' scores. The defect recognition module provides defect analysis at different levels. The trainees take pictures of the corresponding components of the tower according to the patrol rules, analyze the pictures taken, and find out the defects.

[0087] The training personnel can freely set the inspection scenes in different modes. The present invention provides drones of different types and parameters and 9 common tower types such as wine glass tower, cat head tower, dry word tower, etc. for free setting.

[0088] In addition, the simulation platform interface design also sets a navigation mini-map of corresponding scale according to the virtual model of the transmission line, which displays the position of the virtual drone during inspection in real time. The zoom ratio of the mini-map is:

[0089]

[0090] Synchronize the position of the virtual drone on the power line on the mini-map:

[0091] x′=X′·l x ,y′=Y′·l y

[0092] Among them, (x, y) represents the position of the drone on the transmission line, and (x′, y′) is the coordinate position of the drone synchronized on the small map. The size of the roadway model is (X, Y), and (X′, Y′) represents the size of the small map. Create a five-pointed star patch to represent the drone, and ensure that its position is consistent with the position of the virtual drone in the scene in real time. In order to clearly indicate the position of the five-pointed star on the navigation map, render it in red. The five-pointed star patch is used as a reference for the drone and can only be displayed in the navigation map.

Claims

1. A transmission line digital twin-driven drone inspection virtual operation platform, characterized in that: Including: A virtual scene construction module for transmission lines, a digital twin control module, and a simulation platform interface design module; The virtual scene construction module for transmission lines includes a virtual scene model and a three-dimensional drone model. In the modeling process, first, based on three-dimensional data, using the data information of the tower pole shape and various fitting equipment, an integrated modeling of the terrain and landform model of the transmission line, the tower pole model, and the monitoring sensor equipment model is carried out. Then, the 3Ds MAX software is introduced to realize the texture rendering of the three-dimensional model; In the virtual scene, each model is composed of several triangular patches. The virtual scene construction module for transmission lines includes an occlusion culling technology. The occlusion culling technology avoids the phenomenon of sudden changes in models at the edge of the field of view by setting two culling distances; The digital twin control module includes a drone flight motion control module and a data interaction platform module; The data interaction platform module contains a MySQL database, which is responsible for the storage of sensor data and the sending of control data. The data interaction platform module designs two interfaces, namely the connection between the MySQL database and the data transmission end and the communication between the MySQL database and the virtual control platform; The connection with the data transmission end can realize the storage of sensor data by calling the sensor dynamic link library, and the connection with the remote control platform is realized through the Unity3D platform; The design of the simulation platform interface includes a drone model selection module, a mode selection module, a viewing angle switching module, and a scene switching module.

2. According to claim 1, a transmission line digital twin-driven drone inspection virtual operation platform is characterized in that: In the virtual scene model, the camera field of view in the three-dimensional space is projected into the two-dimensional coordinates, and the field of view vector v is obtained by normalization calculation. → =(0,0,1), define the three coordinate points of a triangle as: A(x1,y1,z1), B(x2,y2,z2), C(x3,y3,z3), the normal vector of ΔABC for: Normal vector of ΔABC The projection in the direction of the camera's field of view is: The three-dimensional vector is converted into a two-dimensional coordinate for elimination calculation. At this time, the normal vector of ΔABC With the field of view vector The angle is expressed as: Judge the triangular faces of the model to be culled according to the included angle θ; Set two culling thresholds Dmax and Dmin, and monitor the distance d in real time during the operation of the scene: When d > Dmax, the virtual scene model of the transmission line is outside the viewing angle range, and the virtual scene model of the transmission line in this range is completely culled; When Dmin < d ≤ Dmax, the virtual scene model of the transmission line adjusts the transparency of the rendering material according to the viewing distance, so that models in different positions present different material effects; When d ≤ Dmin, the virtual scene model of the transmission line in the range presents a fine rendering effect; 发射虚拟射线以无人机碰撞器为原点向机身周围发射虚拟射线,实现飞行过程中实时碰撞预警检测;无人机移动飞行过程中,虚拟射线和碰撞体模块启动,虚拟无人机在移动过程中向周围发射虚拟光线,监测机身与其他碰撞体之间的相对距离L;根据模拟飞行条件,设置虚拟无人机的碰撞预警阈值界限Lmax和Lmin;虚拟无人机起飞移动时,射线检测模块开始运行,虚拟交互界面监测窗口实时监控无人机与其他设备、环境模型间的相对距离L:Emit virtual rays around the fuselage with the drone collider as the origin to achieve real-time collision warning detection during flight; during the movement of the drone, the virtual ray and collider module are activated, and the virtual drone emits virtual light around during movement to monitor the relative distance L between the fuselage and other colliders; according to the simulated flight conditions, set the collision warning threshold limits Lmax and Lmin of the virtual drone; when the virtual drone takes off and moves, the ray detection module starts to run, and the virtual interaction interface monitoring window monitors the relative distance L between the drone and other equipment and environmental models in real time: When L > Lmax, the virtual drone moves normally and there is no collision threat; When Lmax > L > Lmin, the distance L enters the warning stage, and the system issues a collision warning signal, prompting the training personnel operating the drone that there may be a collision threat and the training personnel need to adjust the flight attitude and movement trajectory; When L < Lmin, the distance L enters the threat stage, and there may be a collision between the UAV and the tower pole or other obstacles, and collision detection is required; If a collision is detected, the UAV immediately stops flying and hovers; if no collision occurs, the UAV's motion trajectory is re-planned according to the obstacle information, and the flight path is adjusted.

3. The transmission line digital twin-driven UAV inspection virtual operation platform according to claim 1 is characterized in that: In the UAV flight motion control module, the motion states of the quadrotor UAV have four basic forms: vertical lifting motion, roll motion, pitch motion, and yaw motion; the rotor speeds of the quadrotor UAV are expressed as: oh i =ω0+δω i ,i=1,2,3,4 Where ω0 represents the rotor speed during hovering, Δω i Indicates the adjustable amount on a hover basis; The vertical lifting motion of the quadrotor UAV is achieved by simultaneously changing the speeds of the four blades, and the speeds ω of the four rotors are the same, ensuring that the speeds of the four rotors are consistent and the lift generated by the rotors is equal; 4. The transmission line digital twin-driven UAV inspection virtual operation platform according to claim 1 is characterized in that: The UAV flight motion control module also includes a UAV obstacle avoidance control strategy. During the movement of the UAV, first, a global navigation path is planned according to the established initial transmission line model and the initialized target parameters, and the trainer controls the virtual UAV through the handle; When the sensors carried by the UAV collect obstacle information, it is judged whether the relative distance between the UAV and the dynamic obstacle is less than the system collision warning threshold value according to the set obstacle influence distance. If it enters the collision warning threshold, the aircraft enters local avoidance; obstacle avoidance control is performed through the composite potential field VFF algorithm and an alarm is sent to the trainer to ensure the safe passage of the UAV through the dynamic threat.

5. The transmission line digital twin-driven UAV inspection virtual operation platform according to claim 1 is characterized in that: The connection between the MySQL database and the remote control platform is to call the stored sensor data on the one hand and save the control commands of the virtual control platform on the other hand; the specific steps to connect to the database are as follows: The first step: Call the MySQL_init() function to allocate and initialize a MySQL database table that matches the connection; The second step: Call the MySQL_option() function to set the connection options and initialize the data structure; The third step: Call the MySQL_connect() function to connect to the database. After successful connection, perform update operations such as insertion and deletion of data tables by writing SQL statements; The fourth step: After the operation is completed, call the MySQL_close() function to close the database.

6. The transmission line digital twin-driven UAV inspection virtual operation platform according to claim 1 is characterized in that: The scene switching module sets the lighting effects at different time periods in the morning, noon, and afternoon according to the needs of the trainer; the perspective switching module provides multi-perspective switching of the UAV perspective and the pan-tilt perspective; the mode selection module provides training mode, assessment mode, and defect recognition mode.

7. The transmission line digital twin-driven UAV inspection virtual operation platform according to claim 1 is characterized in that: The simulation platform interface design also sets a navigation mini-map of a corresponding scale according to the virtual model of the transmission line, and displays the position of the virtual UAV during inspection in real time; the zoom ratio of the mini-map is: Synchronize the position of the virtual UAV on the transmission line on the mini-map: x′=X′·l x ,y′=Y′·l y Among them, (x, y) represents the position of the UAV on the transmission line, and (x′, y′) is the coordinate position of the UAV synchronized on the mini-map; the size of the roadway model is (X, Y), and (X′, Y′) represents the size of the mini-map.

Images