A Local Collision Avoidance Path Planning Method for Substation Inspection UAVs Based on Individual Turning

Abstract

This invention relates to a local collision avoidance path planning method for substation inspection drones based on individual steering. The method employs a local collision avoidance path planning algorithm based on individual steering to plan the local path for drone inspection of equipment within a substation. First, the area to be inspected within the substation is abstracted in two dimensions according to the inspection task, generating a two-dimensional map. Second, the two-dimensional map is preprocessed; considering the non-negligible volume of the inspection equipment within the substation, obstacle boundaries are expanded to avoid collisions. Then, the trajectory angle interval is determined, dividing the area into permissible and prohibited angle intervals, and navigation points are determined. Finally, the trajectory angle interval and navigation points are updated in real time during the movement until the inspection endpoint is reached. This invention can be applied to the planning of local paths for inspection drones during equipment inspection within substations.

Description

Technical Field

[0001] This invention belongs to the field of unmanned aerial vehicle (UAV) inspection path planning, specifically involving a local collision avoidance path planning method for substation inspection UAVs based on individual turning. Background Technology

[0002] With the continuous expansion of the power grid, the workload of power equipment inspection has also increased dramatically. Substations, as a crucial component of the power system, play a key role in connecting the grid and converting and transmitting electrical energy. Therefore, a high intensity of inspection is required for substations to ensure the safety and stability of power transmission. Traditional substation inspections mainly rely on manual methods, which suffer from safety hazards, high labor costs, long inspection cycles, and limited inspection conditions. Therefore, the introduction of unmanned aerial vehicle (UAV) inspection technology has become a hot topic of exploration in the exploration of new unmanned inspection and maintenance models for substations.

[0003] Drone inspection technology can improve inspection efficiency and safety while reducing labor costs. By introducing drone inspections, all-weather, all-time monitoring of equipment within substations can be achieved, reducing the impact of human factors on inspection results and improving inspection accuracy and reliability. Furthermore, drones can inspect dangerous or inaccessible areas, reducing safety risks for workers.

[0004] Drone inspection requires path planning based on the inspection task. Traditional algorithms such as RRT*, BIT, and InformationRRT* suffer from slow computation speed, large data processing volume, and long output paths. This invention employs a local collision avoidance path planning algorithm for substation inspection drones based on individual turning, which plans local paths for substation drone inspections, resulting in better computation speed and path planning capabilities. Summary of the Invention

[0005] The purpose of this invention is to provide a local collision avoidance path planning method for substation inspection drones based on individual steering. This method can perform real-time path planning for complex terrain and has better adaptability than traditional path planning algorithms. This invention can be applied to equipment inspection within substations for planning local paths for inspection drones.

[0006] To achieve the above objectives, the technical solution of this invention is: a local collision avoidance path planning method for substation inspection drones based on individual steering, which employs a local collision avoidance path planning algorithm based on individual steering to plan the local path for drone inspection of equipment within a substation. The method includes:

[0007] Based on the inspection task, the area to be inspected inside the substation is abstracted in two dimensions to generate a two-dimensional map.

[0008] The 2D map is preprocessed, and obstacle boundaries are expanded to avoid collisions.

[0009] Determine the trajectory angle interval, divide it into allowable motion angle interval and prohibited motion angle interval, and determine the navigation point;

[0010] The trajectory angle range is updated in real time during the movement, and the navigation point is updated until the inspection endpoint is reached.

[0011] In one embodiment of the present invention, the specific implementation method of expanding the boundary of the obstacle to avoid collision is as follows:

[0012] Since the size of the inspection drone is not negligible relative to the inspection space, in order to prevent the drone from colliding with the equipment in the substation during the inspection process, it is necessary to "expand" the boundary of the obstacle by increasing the side length of the obstacle by α units.

[0013] In one embodiment of the present invention, the allowable motion angle interval Ψ allow Defined as the set of all feasible angles within the universal set of angles U.

[0014] In one embodiment of the present invention, the permissible motion angle interval Ψ allow For two boundary tangents l L and l g An enclosed area free of obstacles, where l L and l g The field of view boundary of the UAV is defined by point O, which is the origin of the polar coordinate system with the UAV as the origin. Within the allowable motion angle range Ψ... allow The drone can move freely.

[0015] In one embodiment of the present invention, the forbidden angle interval Ψ forbid Defined as the set of all non-movable angles within the universal set of angles U.

[0016] In one embodiment of the present invention, the specific implementation of determining the navigation point is as follows:

[0017] The drone's path consists of a sequence of inspection points. As the drone moves, the next inspection point serves as the navigation point. When the path formed by this is obstructed by an obstacle, a temporary navigation point P needs to be generated. t P t (x t ,y t The coordinates are determined by the following formula:

[0018] P t (x t ,y t )=v'(x v ,y v )+(σx,σy)

[0019] Where, v'(x v ,y v ) represents the coordinates of the boundary point after the obstacle expands; σ is the safety margin factor, σ>0; x,y are the minimum safe distances between the UAV and the obstacle;

[0020] Let P0 be the current position of the drone, P g For the next inspection point location, P0P g With P g The initial path for the navigation point, P0P t P g Is it adding P? t As a safe path following a temporary navigation point; generate a temporary navigation point P. t Then, the path changes from a straight line to a broken line segment, at which point it is necessary to predict the turning position.

[0021] In one embodiment of the present invention, the specific implementation of the predicted steering position operation is as follows:

[0022] Using a calculation method related to the relative distance d, the approximate critical turning angular velocity ω(d) is obtained, and the formula is:

[0023]

[0024] Where, Δθ i The virtual heading angle is related to the relative distance d, and it is expressed as a function with the relative distance d as the independent variable;

[0025]

[0026] In the formula,

[0027]

[0028] β i (d)=f U (θ UO +sign(β-θ UO )+sign(i-2.5)f asin (r,d))

[0029] χ sin,i (d)=sin(-β i (d))

[0030]

[0031] i represents different steering angle types, i = 1, 2, 3, 4; r is the radius of the circumcircle of the obstacle boundary with the obstacle center as the center; θ UOβ is the angle between the drone's direction of motion and the zero axis; β is the angle between the line connecting the drone and the center of the obstacle and the zero axis; f U (θ) indicates that the angle θ is constrained to the angle set U = (-π, π] by adding or subtracting integer multiples of 2π.

[0032] After obtaining the critical turning angular velocity, since the turning timing is related to the angular velocity constraint, the critical turning position of the UAV is determined based on the UAV performance and the real-time judgment of the relative distance d between the UAV and the obstacle. After reaching the position, the turning operation is performed, the trajectory angle interval is redefined, and the inspection task of the next inspection point is executed. Through the constantly changing real-time path planning, the UAV traverses all inspection points, completes the inspection task, and returns to the starting point.

[0033] The present invention also provides a local collision avoidance path planning system for a substation inspection UAV based on individual steering, including a memory, a processor, and computer program instructions stored in the memory and executable by the processor. When the processor executes the computer program instructions, it can implement the steps described above.

[0034] The present invention also provides a computer-readable storage medium having stored thereon computer program instructions that can be executed by a processor, wherein when the processor executes the computer program instructions, it can implement the steps of the method described above.

[0035] Compared to existing technologies, this invention offers the following advantages: It employs a local collision avoidance path planning method for substation inspection drones based on individual steering. Compared to existing path planning methods, this method offers better computational speed and safety, enabling real-time path planning for complex terrains and demonstrating greater adaptability than traditional path planning algorithms. This invention can be applied to equipment inspection within substations, planning the local paths of inspection drones. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the "expansion" of the obstacle boundary.

[0037] Figure 2 For the allowed angular interval Ψ allow Schematic diagram.

[0038] Figure 3 A schematic diagram is set up for temporary navigation points. Detailed Implementation

[0039] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0040] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] like Figure 1 As shown, this embodiment provides a local collision avoidance path planning method for substation inspection drones based on individual steering. The method employs a local collision avoidance path planning algorithm based on individual steering to plan the local inspection path for drones inspecting equipment within a substation. First, the area to be inspected within the substation is abstracted into a two-dimensional map based on the inspection task. Second, the two-dimensional map is preprocessed; considering the non-negligible volume of the inspection equipment within the substation, obstacle boundaries are expanded to avoid collisions. Then, the trajectory angle interval is determined, dividing the area into permissible and prohibited angle intervals, and navigation points are determined. Finally, the trajectory angle interval and navigation points are updated in real time during the movement until the inspection endpoint is reached.

[0043] The following is the specific implementation process of this example.

[0044] (1) Generate a two-dimensional planar map of the substation interior. Since the size of the inspection drone is not negligible relative to the inspection space, to prevent collisions between the drone and equipment within the substation during inspection, the obstacle boundaries need to be "expanded," increasing the side length of the obstacles by α units. For example... Figure 1 As shown ( Figure 1 In the diagram, V represents the original boundary of the obstacle, and V' represents the boundary of the obstacle after expansion.

[0045] (2) Determine the allowable angle of motion interval. Allowable angle of motion interval Ψ allow Defined as the set of all feasible angles within U, with the corresponding forbidden angle interval Ψ forbid Defined as the set of all non-movable angles within U. Allowable angle interval Ψ. allow For two boundary tangents l L and l g An enclosed area free of obstacles, where l L and l g The field of view boundary of the drone is defined by point O, which is the origin of the polar coordinate system with the drone as the origin. Figure 2As shown, the drone can move freely within this permissible angular range.

[0046] (3) The UAV path is usually composed of a sequence of inspection points. When the UAV moves, it usually uses the next inspection point as the navigation point. When the path formed by this is blocked by an obstacle, a temporary navigation point P needs to be generated. t P t (x t ,y t The coordinates can be determined by the following formula.

[0047] P t (x t ,y t )=v'(x v ,y v )+(σx,σy)

[0048] Where, v'(x v ,y v ) represents the coordinates of the boundary point after the obstacle expands; σ is the safety margin factor, σ>0. For example... Figure 3 As shown.

[0049] Figure 3 P0 represents the current position of the drone, P g For the next inspection point location, P0P g With P g The initial path for the navigation point, P0P t P g Is it adding P? t This serves as a safe path after the temporary navigation point. A temporary navigation point P is generated. t Then, the path changes from a straight line to a broken line segment, at which point it is necessary to predict the turning position.

[0050] (4) Determine the critical turning angular velocity. This invention employs a calculation method related to the relative distance d between the two objects to obtain the approximate critical turning angular velocity ω(d). The formula is as follows:

[0051]

[0052] Where, Δθ i The virtual heading angle is related to d, and can be expressed as a function with d as the independent variable.

[0053]

[0054] In the formula,

[0055]

[0056] β i (d)=f U (θ UO+sign(β-θ UO )+sign(i-2.5)f asin (r,d))

[0057] χ sin,i (d)=sin(-β i (d))

[0058]

[0059] i represents different steering angle types, i = 1, 2, 3, 4; r is the radius of the circumcircle of the obstacle boundary with the obstacle center as the center; θ UO β is the angle between the drone's direction of motion and the zero axis; β is the angle between the line connecting the drone and the center of the obstacle and the zero axis; f U (θ) indicates that the angle θ is constrained to the universal set U = (-π, π] by adding or subtracting integer multiples of 2π.

[0060] After obtaining the critical angular velocity, since the turning timing is mainly related to the angular velocity constraint, the critical turning position of the UAV is determined based on the UAV performance and the real-time judgment of the distance d between the UAV and the obstacle. After reaching the position, the turning operation is performed, and the process returns to step (2) to execute the inspection task of the next inspection point.

[0061] (5) Through constantly changing real-time path planning, the UAV traverses all inspection points, completes the inspection task, and returns to the starting point.

[0062] The present invention also provides a local collision avoidance path planning system for a substation inspection UAV based on individual steering, including a memory, a processor, and computer program instructions stored in the memory and executable by the processor. When the processor executes the computer program instructions, it can implement the steps described above.

[0063] The present invention also provides a computer-readable storage medium having stored thereon computer program instructions that can be executed by a processor, wherein when the processor executes the computer program instructions, it can implement the steps of the method described above.

[0064] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0065] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0066] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0067] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A local collision avoidance path planning method for a substation inspection UAV based on individual steering, characterized in that, A local collision avoidance path planning algorithm based on individual steering is used to plan the local path for UAV inspection of equipment in a substation; the method includes: Based on the inspection task, the area to be inspected inside the substation is abstracted in two dimensions to generate a two-dimensional map. The 2D map is preprocessed, and obstacle boundaries are expanded to avoid collisions. Determine the trajectory angle interval, divide it into allowable motion angle interval and prohibited motion angle interval, and determine the navigation point; The trajectory angle range is updated in real time during the movement, and the navigation point is updated until the inspection endpoint is reached; The specific implementation method for determining the navigation point is as follows: The drone's path consists of a sequence of inspection points. As the drone moves, the next inspection point serves as the navigation point. When the path formed by this is obstructed by an obstacle, a temporary navigation point P needs to be generated. t P t (x t ,y t The coordinates are determined by the following formula: P t (x t ,y t )=v′(x v ,y v )+(σx,σy) Where, v'(x v ,y v ) represents the coordinates of the boundary point after the obstacle expands; σ is the safety margin factor, σ>0; x,y are the minimum safe distances between the UAV and the obstacle; Let P0 be the current position of the drone, P g For the next inspection point, P0P g With P g The initial path for the navigation point, P0P t P g Is it adding P? t As a safe path following a temporary navigation point; generate a temporary navigation point P. t Then, the path changes from a straight line to a broken line segment, at which point it is necessary to predict the turning position. The specific implementation method of the predicted turning position operation is as follows: Using a calculation method related to the relative distance d, the approximate critical turning angular velocity ω(d) is obtained, and the formula is: Where, Δθ i The virtual heading angle is related to the relative distance d, and it is expressed as a function with the relative distance d as the independent variable; In the formula, β i (d)=f U (θ UO +sign(β-θ UO )+sign(i-2.5)f asin (r,d)) x sin,i (d)=sin(-β i (d)) i represents different steering angle types, i = 1, 2, 3, 4; r is the radius of the circumcircle of the obstacle boundary with the obstacle center as the center; θ UO β is the angle between the drone's direction of motion and the zero axis; β is the angle between the line connecting the drone and the center of the obstacle and the zero axis; f U (θ) indicates that the angle θ is constrained to the angle set U = (-π, π] by adding or subtracting integer multiples of 2π. After obtaining the critical turning angular velocity, since the turning timing is related to the angular velocity constraint, the critical turning position of the UAV is determined based on the UAV performance and the real-time judgment of the relative distance d between the UAV and the obstacle. After reaching the position, the turning operation is performed, the trajectory angle interval is redefined, and the inspection task of the next inspection point is executed. Through the constantly changing real-time path planning, the UAV traverses all inspection points, completes the inspection task, and returns to the starting point.

2. The method for local collision avoidance path planning of a substation inspection UAV based on individual steering as described in claim 1, characterized in that, The specific implementation method for expanding the obstacle boundary to avoid collisions is as follows: Since the size of the inspection drone is not negligible relative to the inspection space, in order to prevent the drone from colliding with the equipment in the substation during the inspection process, it is necessary to "expand" the boundary of the obstacle by increasing the side length of the obstacle by α units.

3. The method for local collision avoidance path planning of a substation inspection UAV based on individual steering as described in claim 1, characterized in that, The allowable motion angle interval Ψ allow Defined as the set of all feasible angles within the universal set of angles U.

4. The method for local collision avoidance path planning of a substation inspection UAV based on individual steering as described in claim 3, characterized in that, The allowable motion angle range Ψ allow For two boundary tangents l L and l g An enclosed area free of obstacles, where l L and l g The field of view boundary of the UAV is defined by point O, which is the origin of the polar coordinate system with the UAV as the origin. Within the allowable motion angle range Ψ... allow The drone can move freely.

5. The method for local collision avoidance path planning of a substation inspection UAV based on individual steering as described in claim 1, characterized in that, The forbidden angle interval Ψ forbid Defined as the set of all non-movable angles within the universal set of angles U.

6. A local collision avoidance path planning system for a substation inspection UAV based on individual steering, characterized in that, It includes a memory, a processor, and computer program instructions stored in the memory and executable by the processor, which, when executed by the processor, enable the implementation of the steps of the method as described in any one of claims 1-5.

7. A computer-readable storage medium having stored thereon computer program instructions executable by a processor, wherein when the processor executes the computer program instructions, it is able to implement the steps of the method as described in any one of claims 1-5.

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