CN117289705B

CN117289705B - Path determination method and device

Info

Publication number: CN117289705B
Application number: CN202311534462.7A
Authority: CN
Inventors: 贺春; 么军; 刘力卿; 张弛; 季洪鑫; 李松原; 魏菊芳; 陈荣; 李琳
Original assignee: State Grid Corp of China SGCC; State Grid Tianjin Electric Power Co Ltd; Electric Power Research Institute of State Grid Tianjin Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; State Grid Tianjin Electric Power Co Ltd; Electric Power Research Institute of State Grid Tianjin Electric Power Co Ltd
Priority date: 2023-11-17
Filing date: 2023-11-17
Publication date: 2024-03-26
Anticipated expiration: 2043-11-17
Also published as: CN117289705A

Abstract

The invention provides a path determining method and a path determining device, which can be applied to the technical field of robot path planning. The method comprises the following steps: responding to a path determination request, determining a starting point of a position of the robot in a preset coordinate system and a target point of a target position included in the path determination request in the preset coordinate system, wherein the preset coordinate system is determined based on a closed space of the robot, and the closed space comprises at least one obstacle object; path planning is carried out based on projections of a starting point, a target point, a closed space and at least one obstacle object in a plurality of orthogonal planes respectively, so as to obtain path curves related to the orthogonal planes respectively, wherein the orthogonal planes are determined based on a preset coordinate system; and obtaining a target path from the position where the robot is located to the target position based on the path curves associated with each of the plurality of orthogonal planes.

Description

Path determination method and device

Technical Field

The present invention relates to the field of robot path planning technologies, and in particular, to a path determining method and apparatus.

Background

The reduction of the internal electrical insulation performance of the large-scale transformer is a main cause of failure, and can cause interphase short circuit between all phase windings, turn-to-turn short circuit between partial turns of the single-phase winding, single-phase winding or outgoing line through the shell to generate single-phase grounding faults and other serious problems. The existing power equipment partial discharge on-line monitoring system fails to combine the characteristic change of the partial discharge signal with the insulator fault of the electrical equipment, and the reliable judgment of the discharge type, the discharge position and the discharge severity inside the large transformer is difficult to realize through a partial discharge method. Therefore, the internal inspection robot is arranged in the internal space of the large transformer, so that the internal inspection robot can autonomously move in the space and timely detect and maintain faults.

The internal inspection robot adopted by the conventional maintenance of the transformer faults is small in size and limited in cruising ability, and when the internal inspection robot is patrolled and sighted in large transformer oil, the internal inspection robot cannot finish detection tasks even because the internal space of the transformer is huge and the moving path is unreasonable, so that the distance and time of the internal inspection robot moving in the transformer are long.

Disclosure of Invention

In view of the above, the present invention provides a path determining method and apparatus.

One aspect of the present invention provides a path determining method, including: responding to a path determination request, determining a starting point of a position of the robot in a preset coordinate system and a target point of a target position included in the path determination request in the preset coordinate system, wherein the preset coordinate system is determined based on a closed space of the robot, and the closed space comprises at least one obstacle object; path planning is carried out based on projections of a starting point, a target point, a closed space and at least one obstacle object in a plurality of orthogonal planes respectively, so as to obtain path curves related to the orthogonal planes respectively, wherein the orthogonal planes are determined based on a preset coordinate system; and obtaining a target path from the position where the robot is located to the target position based on the path curves associated with each of the plurality of orthogonal planes.

According to an embodiment of the invention, the plurality of orthogonal planes comprises at least one first plane and at least one second plane, wherein an included angle between the first plane and the target plane is smaller than a preset angle, and the target plane comprises a closed space and a connecting surface of each of the at least one obstacle object; the method comprises the steps of carrying out path planning based on projections of a starting point, a target point, a closed space and at least one obstacle object in a plurality of orthogonal planes, obtaining path curves related to the orthogonal planes, and the method comprises the following steps: for the first plane, taking a first projection area of the closed space in the first plane and a second projection area of at least one obstacle object in the first plane as constraint, and carrying out path planning based on a first projection point of a starting point in the first plane and a second projection point of a target point in the first plane to obtain a path curve related to the first plane; and for the second plane, obtaining a path curve related to the second plane based on the third projection point of the starting point on the second plane and the fourth projection point of the target point on the second plane.

According to an embodiment of the present invention, with a first projection area of a closed space on a first plane and a second projection area of at least one obstacle object on the first plane as constraints, path planning is performed based on a first projection point of a starting point on the first plane and a second projection point of a target point on the first plane, so as to obtain a path curve related to the first plane, including: generating a repulsive force field of the first plane based on the first projection region and the second projection region; generating a gravitational field of the first plane based on the second projection point; and carrying out path planning by utilizing a progressive optimal rapid random search tree method based on the repulsive field and the gravitational field to obtain a path curve between the first projection point and the second projection point.

According to an embodiment of the present invention, path planning is performed by using a progressive optimal fast random search tree method based on a repulsive field and a gravitational field, to obtain a path curve between a first projection point and a second projection point, including: determining a sampling point in a first plane based on a leaf node, a repulsive force field and a gravitational field of a current path, wherein a root node of the current path is a first projection point; generating path nodes in a first plane along the direction from the leaf nodes of the current path to the sampling points based on a preset step length; determining at least one alternative node which is positioned in a circular area taking a path node as a center and a first radius as a radius from a plurality of nodes included in a current path; determining an associated node of the path node based on the path cost between the path node and each of the at least one candidate node; under the condition that the distance between the path node and the second projection point is smaller than or equal to a preset step length, obtaining a path curve based on the current path, the associated node of the path node, the path node and the second projection point; and obtaining a new current path based on the associated node of the path node and the current path under the condition that the distance between the path node and the second projection point is larger than a preset step length.

According to an embodiment of the present invention, obtaining a path curve based on a current path, an associated node of the path node, and a second projection point includes: determining a plurality of first nodes forming a path curve based on the current path, the associated nodes of the path nodes, the path nodes and the second projection points; performing interpolation processing on the plurality of first nodes to obtain a plurality of second nodes; and smoothing the plurality of first nodes and the plurality of second nodes by utilizing a sliding time window method to obtain a path curve.

According to an embodiment of the present invention, a path curve is obtained based on a current path, an associated node of the path node, and a second projection point, and further includes: determining a second radius based on the first radius if it is determined that the path node satisfies the local extremum condition; wherein determining at least one candidate node located in a circular area with a first radius as a radius and taking a path node as a center from a plurality of nodes included in a current path comprises: at least one candidate node located within a circular region centered at a path node and having a second radius is determined from a plurality of nodes included in the current path.

According to an embodiment of the present invention, a path curve associated with a second plane is obtained based on a third projection point of a start point on the second plane and a fourth projection point of a target point on the second plane, including: and obtaining a path curve related to the second plane based on the connection curve between the third projection point and the fourth projection point.

According to an embodiment of the present invention, the enclosed space is divided into a plurality of grids; the method for determining the starting point of the position of the robot in the preset coordinate system and the target point of the target position included in the path determination request in the preset coordinate system comprises the following steps: determining at least one first grid associated with the robot based on the location of the robot; obtaining a starting point based on the coordinates of at least one first grid in a preset coordinate system respectively; determining at least one second grid associated with the target location based on the target location; and obtaining the target point based on the coordinates of each of the at least one second grid in the preset coordinate system.

According to an embodiment of the invention, the enclosed space comprises an internal cavity of the transformer; the at least one obstacle object comprises at least one winding inside the transformer.

Another aspect of the present invention provides a path determining apparatus, comprising:

The first determining module is used for responding to the path determining request, determining a starting point of the position of the robot in a preset coordinate system and a target point of the target position included in the path determining request in the preset coordinate system, wherein the preset coordinate system is determined based on a closed space of the robot, and the closed space comprises at least one obstacle object;

the second determining module is used for carrying out path planning based on projections of the starting point, the target point, the closed space and at least one obstacle object in a plurality of orthogonal planes to obtain path curves related to the orthogonal planes, wherein the orthogonal planes are determined based on a preset coordinate system;

and the third determining module is used for obtaining a target path from the position of the robot to the target position based on the path curves related to the orthogonal planes.

Another aspect of the present invention provides an electronic device, including: one or more processors; and a memory for storing one or more instructions that, when executed by the one or more processors, cause the one or more processors to implement the method as described above.

Another aspect of the invention provides a computer readable storage medium storing computer executable instructions that when executed are configured to implement a method as described above.

Another aspect of the invention provides a computer program product comprising computer executable instructions which, when executed, are adapted to carry out the method as described above.

According to the embodiment of the invention, the solving problem of the three-dimensional path is converted into a plurality of two-dimensional path planning problems in a plurality of orthogonal planes by establishing a preset coordinate system and projecting each element of the determined path into each orthogonal plane of the preset coordinate system, the path planning is respectively realized in the orthogonal planes, and the three-dimensional path in the space is generated by a path synthesis method. The number of the generated path prediction nodes is reduced, and the time cost and the calculation burden of path planning are reduced.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings, in which:

FIG. 1 schematically illustrates a scenario in which a path determination method and apparatus may be applied according to an embodiment of the present invention;

FIG. 2 schematically illustrates a flow chart of a path determination method according to an embodiment of the invention;

FIG. 3A schematically illustrates a graph of a spatial trajectory according to an embodiment of the invention;

FIG. 3B schematically illustrates a coordinate diagram of a spatial trajectory orthogonal decomposition in accordance with an embodiment of the present invention;

FIG. 4 schematically illustrates a graph of curvature optimization in accordance with an embodiment of the invention;

FIG. 5A schematically illustrates a schematic diagram of a grid representing an enclosed space according to an embodiment of the present invention;

fig. 5B schematically shows a schematic view of a grid representing a closed space and a grid representing an obstacle according to an embodiment of the present invention;

fig. 5C schematically shows a schematic view of a grid representing a closed space and a grid representing an obstacle and a movement path of a robot according to an embodiment of the present invention;

FIG. 6 schematically illustrates a block diagram of a closed space and its internal space modeling in accordance with an embodiment of the present invention;

fig. 7 schematically shows a block diagram of a path determining apparatus according to an embodiment of the invention; and

fig. 8 schematically shows a block diagram of an electronic device adapted to implement a path determination method according to an embodiment of the invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be understood that the description is only illustrative and is not intended to limit the scope of the invention. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. It may be evident, however, that one or more embodiments may be practiced without these specific details. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The terms "comprises," "comprising," and/or the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. It should be noted that the terms used herein should be construed to have meanings consistent with the context of the present specification and should not be construed in an idealized or overly formal manner.

Where expressions like at least one of "A, B and C, etc. are used, the expressions should generally be interpreted in accordance with the meaning as commonly understood by those skilled in the art (e.g.," a system having at least one of A, B and C "shall include, but not be limited to, a system having a alone, B alone, C alone, a and B together, a and C together, B and C together, and/or A, B, C together, etc.).

Space path planning is one of key technologies of intelligent agent control, and aims to avoid obstacles according to a certain optimal index and safely reach a designated position under the condition that the surrounding environment is known or partially known. Compared with intelligent equipment moving in a two-dimensional space, the complexity and difficulty of path planning of the three-dimensional space are greatly improved along with the rising of dimensions. The common algorithms for solving the three-dimensional space trajectory planning problem include an A-search method, a genetic algorithm, a fast-expansion random tree, an artificial potential field method, a case-based reasoning method, an ant colony algorithm and the like, but all have the problems of large calculation amount, long planning time consumption and inapplicability to real-time operation environment. This is mainly manifested in that when a three-dimensional space path is searched, the generated path has a large randomness, and long searching time, slow convergence, easy deadlock and the like can be generated. Aiming at path planning of a three-dimensional space of a complex environment, the defect is more obvious, and a feasible path meeting constraint conditions is difficult to find.

In view of this, the present invention provides a method for using artificial potential fields in combination with progressive optimal fast random search trees: firstly, modeling the space environment in a large oil immersed transformer by adopting a grid method, aiming at the path planning problem in the fault detection process in the transformer, taking the influence of winding obstacles into consideration, providing a dimension-reducing path planning method, and decomposing the space three-dimensional path planning problem into path planning problems on two orthogonal planes; secondly, because an artificial potential field is applied, attractive force and repulsive force are generated between the target and the obstacle, and the algorithm searching speed and the global optimizing capability are improved; and finally, considering the influence of path curvature continuity on the motion of the flaw detection actuator, adopting a cubic B spline to connect nodes of the generated path, and optimizing curve related parameters to ensure that the curvature of the planned path is continuous and the minimum turning radius constraint of the actuator is met, thereby effectively improving the searching speed and the global optimizing capability of the path planning algorithm of the large-scale transformer internal inspection robot.

In particular, embodiments of the present invention provide a path determining method, a path determining apparatus, an electronic device, a readable storage medium, and a computer program product. The method comprises the steps of responding to a path determination request, determining a starting point of a position of a robot in a preset coordinate system and a target point of a target position included in the path determination request in the preset coordinate system, wherein the preset coordinate system is determined based on a closed space of the robot, and at least one obstacle object is included in the closed space; path planning is carried out based on projections of a starting point, a target point, a closed space and at least one obstacle object in a plurality of orthogonal planes respectively, so as to obtain path curves related to the orthogonal planes respectively, wherein the orthogonal planes are determined based on a preset coordinate system; and obtaining a target path from the position where the robot is located to the target position based on the path curves associated with each of the plurality of orthogonal planes.

It should be noted that the method and the device for determining the path determined by the embodiment of the invention can be used in the field of robot path planning. For example, the method and the device for determining the path determined by the embodiment of the invention can be used in any field except the field of robot path planning. For example, the application fields of the path determining method and the path determining device according to the embodiments of the present invention are not limited.

In embodiments of the present invention, the data involved (e.g., including but not limited to user personal information) is collected, updated, analyzed, processed, used, transmitted, provided, disclosed, stored, etc., all in compliance with relevant legal regulations, used for legal purposes, and without violating the public welfare. In particular, necessary measures are taken for personal information of the user, illegal access to personal information data of the user is prevented, and personal information security, network security and national security of the user are maintained.

In embodiments of the present invention, the user's authorization or consent is obtained before the user's personal information is obtained or collected.

Fig. 1 schematically shows a scenario in which a path determination method and apparatus may be applied according to an embodiment of the present invention. It should be noted that fig. 1 is only a scenario in which an embodiment of the present invention may be applied to help those skilled in the art understand the technical content of the present invention, but it does not mean that the embodiment of the present invention may not be applied to other devices, systems, environments, or scenarios.

As shown in fig. 1, a system architecture 100 according to this embodiment may include an enclosed space 101, an obstacle object 102, and a robot 103.

Wherein the obstacle object 102 and the robot 103 are in the enclosed space 101, the robot 103 needs to find a path in the enclosed space 101 from the start point to the target point, wherein the path needs to avoid the boundary of the obstacle object 102 and the enclosed space 101.

It should be understood that the number of obstacle objects and robots in the enclosed space of fig. 1 is merely illustrative. There may be any number of enclosed spaces, obstacle objects and robots, as desired for implementation.

Fig. 2 schematically shows a flow chart of a path determination method according to an embodiment of the invention.

As shown in FIG. 2, the method includes operations S210-S230.

In operation S210, in response to the path determination request, a start point of a position in which the robot is located in a preset coordinate system and a target point of a target position included in the path determination request in the preset coordinate system are determined, wherein the preset coordinate system is determined based on a closed space in which the robot is located, and the closed space includes at least one obstacle object therein.

According to an embodiment of the present invention, the preset coordinate system may be a space cartesian coordinate system established by taking one end point of the closed space as an origin and three mutually perpendicular sides of the closed space as coordinate axes. The starting point of the robot may be determined by the positioning signal of the robot itself. The target position may be a position in a closed space to which the robot needs to reach, and the target point may be determined in a preset coordinate system according to the target position. The path determination request may be used to determine a path of the robot from a start point to a target point within the enclosed space.

In operation S220, path planning is performed based on projections of the starting point, the target point, the closed space, and the at least one obstacle object in each of a plurality of orthogonal planes, and path curves associated with each of the plurality of orthogonal planes are obtained, wherein the plurality of orthogonal planes are determined based on a preset coordinate system.

According to the embodiment of the invention, after the preset coordinate system is determined, a plurality of orthogonal planes in the preset coordinate system can be determined. Projecting the starting point, the target point, the closed space and at least one obstacle into each orthogonal plane, and respectively planning paths in each orthogonal plane to obtain a path curve of the robot from the starting point to the target point in each orthogonal plane.

In operation S230, a target path from a position where the robot is located to a target position is obtained based on path curves associated with each of the plurality of orthogonal planes.

According to the embodiment of the invention, based on the path curves of the robot from the starting point to the target point in each orthogonal plane, each path curve is synthesized in the three-dimensional space, so that the target path of the robot from the starting point to the target point in the closed space is obtained.

According to an embodiment of the present invention, the space is enclosedΩ∈R ^d Continuous bounded function in (a)C（t）：[t ₀ ，t _f ]→R ^d Is a path in the closed space. Assume that k obstacle objects exist in a closed space O _i ，i=1,2,3，…，kDefinition of free spaceΩ _free =Ω/ΣO _i Given thatΩ _free Two points in the interiorP ₀ AndP _f find a pathC（t）∈Ω _free Enabling the robot P to followC（t）From the slaveP ₀ Move toP _f . Along with the increase of the dimension, the computational complexity of path planning in the space is obviously increased, so that planning solution cannot be completed in a limited time, and therefore, the path in the high-dimension space is subjected to orthogonal decomposition, the high-dimension path planning is subjected to dimension reduction treatment, and a final result is obtained through path synthesis.

According to an embodiment of the present invention, the target plane may be regarded as the first plane. And respectively projecting the starting point, the target point, the closed space and the obstacle object to a first plane to obtain a first projection area of the closed space, a second projection area of the obstacle object, a first projection point of the starting point and a second projection point of the target point. The curve from the first projection point, avoiding the boundary of the first projection area and the second projection area, and reaching the second projection point may be a path curve associated with the first plane. The plane other than the first plane may be used as a second plane, and the starting point and the target point may be projected onto the second plane, respectively, to obtain a third projection point of the starting point and a fourth projection point of the target point. From the third projection point, the curve reaching the fourth projection point may be a path curve associated with the second plane.

Fig. 3A schematically shows a graph of a spatial trajectory according to an embodiment of the invention.

As shown in fig. 3A, the robot P needs to start from the start point P ₀ Move to the target point P _f The three-dimensional path planning problem in the three-dimensional space has high calculation complexity and is unfavorable for quickly determining the path because a curve path is needed to pass.

Fig. 3B schematically shows a schematic diagram of an orthogonal decomposition of a spatial trajectory according to an embodiment of the invention.

As shown in fig. 3B, the space is divided into three orthogonal planes XY, XZ and YZ by a space cartesian coordinate system ozz, wherein the obstacle object has no influence on the path construction in the two planes due to a large gap between the obstacle object and the planes XY, YZ, and the planes XZ and YZThe included angle between the target planes is smaller than a preset angle, and the included angle is a first plane, and one of the planes XY and YZ can be used as a second plane. Paths in spaceC(t)Can be projected onto the plane XZ and the plane XY respectively to form a pathC _xz （t）AndC _xy （t）. The three-dimensional path planning problem can be converted into the two-dimensional path planning problem on the orthogonal plane, the path planning is respectively realized in the two-dimensional plane, and the paths in the three-dimensional space can be obtained in a path synthesis mode, so that the calculation complexity is greatly reduced. And establishing a relation between the xz plane and a two-dimensional path in the xy plane through a common x coordinate value to complete path synthesis.

According to the embodiment of the invention, a virtual artificial potential field can be constructed in a first plane, wherein a target point generates a gravitational field for a robot, the direction of the gravitational field, which points to the target point, is a positive direction, the farther the robot is from the target point, the larger the received gravitational force is, the obstacle object and the closed space generate a repulsive force field, the direction, which points to the boundary between the obstacle object and the closed space, in the repulsive force field is a negative direction, the closer the robot is from the boundary between the obstacle object and the closed space, the larger the received repulsive force is, the maximum value appears at the boundary position of the obstacle object and the boundary position of the closed space, and the robot effectively avoids the boundary between the obstacle object and the closed space under the combined action of the gravitational force and the repulsive force and moves to the target point position. Wherein, Repulsive force fieldU _rep The determination can be made according to the first projection area of the closed space and the second projection area of the obstacle object, as shown in formula (1):

（1）

wherein,k _r for the repulsive force field coefficient, I.I ₂ As a 2-norm of the vector,xis the coordinates of any point in the plane,is the boundary of the obstacle object and the boundary of the closed space, as shown in the formula (2):

（2）

wherein,x _obs is the inner point of the obstacle object and the point outside the boundary of the closed space.

According to an embodiment of the invention, the gravitational fieldU _att Can be determined from the second projection point of the target point as shown in formula (3):

（3）;

wherein,k _p for the coefficient of the gravitational field,x _g as the target point of the object to be processed,r _g is the target radius. Synthesizing the gravitational field and the repulsive field to obtain an artificial potential field in the closed spaceU _a As shown in formula (4):

（4）;

obtaining an artificial potential fieldU _a Thereafter based onU _a Generating virtual forces of artificial potential fieldsF _a As shown in formula (5):

（5）;

virtual force based on artificial potential fieldF _a And carrying out path planning by utilizing a progressive optimal rapid random search tree method to obtain a path curve between the first projection point and the second projection point.

According to the embodiment of the invention, a collision-free path can be planned between the starting point of the miniature bionic fish and the target point by using the artificial potential field method, but the planned path may not be the collision-free path with the shortest path and the optimal quality. Therefore, a path is planned by using an artificial potential field and a progressive optimal fast random search tree method.

According to an embodiment of the present invention, path planning is performed by using a progressive optimal fast random search tree method based on a repulsive field and a gravitational field, to obtain a path curve between a first projection point and a second projection point, including: determining a sampling point in a first plane based on a leaf node, a repulsive force field and a gravitational field of a current path, wherein a root node of the current path is a first projection point; generating path nodes in a first plane along the direction from the leaf nodes of the current path to the sampling points based on a preset step length; determining at least one alternative node which is positioned in a circular area taking a path node as a center and a first radius as a radius from a plurality of nodes included in a current path; determining an associated node of the path node based on the path cost between the path node and each of the at least one candidate node; under the condition that the distance between the path node and the second projection point is smaller than or equal to a preset step length, obtaining a path curve based on the current path, the associated node of the path node, the path node and the second projection point; and under the condition that the distance between the path node and the second projection point is larger than a preset step length, obtaining a new current path based on the associated node of the path node and the current path.

According to an embodiment of the invention, the node may be a point in the first plane through which the robot may pass. The leaf node may be the currently selected node. The sampling point can be determined according to leaf node, repulsive field and gravitational fieldThe leaf node may determine the direction to the target point based on the direction of the sampling point. The current path may be the currently determined path from the root node to the target point. The path curve may be the final determined path from the root node to the target point in the first plane. At an initial time, the root node may act as a leaf node for determining sampling points in the first plane. Wherein, sampling pointx _rand Virtual forces of artificial potential fields that can be experienced according to the position of leaf nodes of the current pathF _a As shown in formula (6):

（6）;

wherein,x _parent as a parent node of the sampling point,k _U as an empirical coefficient, the setting can be performed according to a specific application scenario. After the sampling point is determined, selecting a point with the distance from the leaf node of the current path as a preset step length as a path node according to the direction from the leaf node of the current path to the sampling point. After the path node is used as a circle center and the first radius is used as a radius to make a circle, the node of the current path in the circular area can be used as an alternative node. And respectively calculating the distance between each candidate node and the path node, and selecting the candidate node with the smallest distance as the associated node of the path node. Under the condition that the distance between the path node and the second projection point is smaller than or equal to a preset step length, selecting a section of line from the first projection point to the associated node of the path node according to the current path, connecting the section of line with the path node and connecting the line to the second projection point to obtain a path curve; and under the condition that the distance between the path node and the second projection point is larger than a preset step length, selecting a section of line from the first projection point to the associated node of the path node according to the current path, connecting the path node to obtain a new line, updating the current path by the new line, and continuously calculating the next path node.

According to the embodiment of the invention, the direction of the path node is determined based on the gravitational field and the repulsive force field in the artificial potential field, the position of the path node is determined according to the preset step length, the alternative node is determined according to the first radius, and the node with the minimum distance with the path node is selected from the alternative nodes as the associated node of the path node so as to add the path node into the current path. It is ensured that the determined path can bypass the boundary of the obstacle object and the enclosed space and that a relatively short route can be selected.

According to the embodiment of the invention, the problem of path generation in a closed space is solved by using an artificial potential field improved progressive optimal fast random search tree method, namely a safe path can be quickly searched, but the improved progressive optimal fast random search tree method is used for connecting two nodes in a straight line, so that the problems of discontinuous curvature of turning points, overlarge turning angles and the like of a path globally planned by an algorithm are caused. Because the abrupt change of curvature can cause the abrupt change of the direction rotation angle, the global path directly planned by the improved progressive optimal rapid random search tree method is not suitable for tracking the track of the robot. The final path thus needs to be able to take into account kinematic constraint constraints while planning the path, and it is often necessary to ensure continuity of path curvature.

According to an embodiment of the present invention, the path may be smoothed using B-spline curves. The B-spline basis function is a K-th order piecewise polynomial determined by a sequence of non-decreasing parameters u called node vectors, taking into account the K-th order B-spline functionc（u）The expression is shown as formula (7):

（7）;

wherein,d _i in order to control the point of the control,N _（i，k） （u）is a k-order B spline basis function, as shown in the formulas (8) and (9):

（8）;

（9）;

segment given {u _i }={u _i -u _i-1 =1The cubic B-spline basis function thus obtained is shown in formula (10):

（10）;

the cubic B-spline expression function is thus as shown in equation (11):

（11）;

after a series of control points are given, a curve meeting the requirements can be obtained according to the formula (11).

Fig. 4 schematically shows a graph of curvature optimization according to an embodiment of the invention.

As shown in fig. 4, the robot slave is determined using a modified progressive optimal fast random search tree methodx ₀ To the point ofx _f After the current path, the associated node of the path node, the path node and the second projection pointx ₀ To the point ofx _f The nodes are used as a first node for forming a path curve, a B spline curve equation is constructed by the first node, a second node is calculated by the B spline curve equation, sampling points are sequentially selected on the path at fixed intervals as control points by a sliding time window method, so that a B spline curve of the track is generated, and a curvature optimization result is obtained.

According to an embodiment of the present invention, the use of artificial potential fields may cause a problem of lateral expansion of the search path caused by equipotential lines, and a phenomenon of trapping in a local solution caused by potential field singularities that may be formed. In order to avoid the problems caused by the algorithm, a target approximation method is introduced in the random generation sampling point process of the random tree, and the calculation is performed through a formula (6)x _rand And performs judgment as shown in the formula (12):

（12）；

wherein isIs a function of the (i) th iteration,δandεto select a threshold.

If the condition of equation (12) persists, it indicates that the current node satisfies the local extremum condition, and the selection of the alternative node needs to be adjusted. A second radius is determined based on the first radius, wherein the second radius is greater than the first radius. And according to the newly determined second radius, taking the path node as the circle center, taking the second radius as the radius to make a circle, and taking the node of the current path in the circular area as a new alternative node.

According to an embodiment of the present invention, a connection curve between the third projection point and the fourth projection point may be arbitrarily determined, and for example, the connection curve may be a straight line from the start point to the target point.

According to an embodiment of the present invention, the enclosed space may be discretized, with a finite uniform point representing a continuous obstacle object. A rectangular coordinate system can be established in the closed space, and uniform equal-length division is performed in three axial directions. The internal structure model of the closed space is simplified to be regarded as a cuboid space, and the space model is composed of a boundary of the closed space and an obstacle object. When the structure in the enclosed space is less than one grid, it can be regarded as occupying one grid.

Fig. 5A schematically shows a schematic view of a grid representing a closed space according to an embodiment of the invention.

Fig. 5B schematically shows a schematic view of a grid representing a closed space and a grid representing an obstacle according to an embodiment of the present invention.

Wherein the grids representing the enclosed space equally divide the enclosed space into continuous grids, and the grids representing the obstacle objects equally divide the obstacle objects into continuous grids and are connected with the grids representing the enclosed space.

Fig. 5C schematically shows a schematic view of a grid representing a closed space and a grid representing an obstacle and a movement path of a robot according to an embodiment of the present invention.

Wherein the robot is driven by the artificial potential fieldx ₀ To move tox _f Is the path ofC(t)。

Fig. 6 schematically shows a block diagram of a closed space and its internal space modeling according to an embodiment of the present invention.

As shown in fig. 6, the enclosed space of this embodiment and its internal space modeling include windings 601 and enclosed space 602. The movement of the robot in the enclosed space 602 needs to bypass the windings 601 from the starting point to the target point.

It should be noted that, unless there is an execution sequence between different operations or an execution sequence between different operations in technical implementation, the execution sequence between multiple operations may be different, and multiple operations may also be executed simultaneously.

Fig. 7 schematically shows a block diagram of a path determining apparatus according to an embodiment of the invention.

As shown in fig. 7, the path determining apparatus 700 includes a first determining module 710, a second determining module 720, and a third determining module 730.

According to an embodiment of the invention, the second determination module 720 comprises a path planning sub-module and a curve determination sub-module.

The path planning submodule is used for carrying out path planning on a first projection point of a starting point on the first plane and a second projection point of a target point on the first plane by taking a first projection area of a closed space on the first plane and a second projection area of at least one obstacle object on the first plane as constraints respectively, so as to obtain a path curve related to the first plane.

The curve determination submodule is used for obtaining a path curve related to the second plane based on a third projection point of the starting point on the second plane and a fourth projection point of the target point on the second plane.

According to an embodiment of the invention, the path planning sub-module comprises a repulsive force field generating unit, a gravitational field generating unit and a path planning unit.

The repulsive force field generating unit is used for generating a repulsive force field of the first plane based on the first projection area and the second projection area.

The gravitational field generating unit is used for generating a gravitational field of the first plane based on the second projection point.

The path planning unit is used for carrying out path planning by utilizing a progressive optimal fast random search tree method based on the repulsive field and the gravitational field to obtain a path curve between the first projection point and the second projection point.

According to an embodiment of the invention, the path planning unit comprises a sampling point determination subunit, a path node generation subunit, an alternative node determination subunit, an association node determination subunit, a path curve determination subunit and a current path determination subunit.

The sampling point determining subunit is configured to determine a sampling point in a first plane based on a leaf node, a repulsive force field, and a gravitational field of the current path, where a root node of the current path is a first projection point.

The path node generation subunit is used for generating path nodes in the first plane along the direction from the leaf nodes of the current path to the sampling points based on a preset step length.

The alternative node determining subunit is configured to determine, from a plurality of nodes included in the current path, at least one alternative node located in a circular area with the path node as a center and the first radius as a radius.

The associated node determining subunit is configured to determine an associated node of the path node based on a path cost between the path node and each of the at least one candidate node.

The path curve determining subunit is configured to obtain a path curve based on the current path, the associated node of the path node, and the second projection point when the distance between the path node and the second projection point is less than or equal to a preset step.

The current path determining subunit is configured to obtain a new current path based on the associated node of the path node and the current path when the distance between the path node and the second projection point is greater than a preset step length.

According to an embodiment of the present invention, the path curve determination subunit includes a first node determination component, an interpolation processing component, a smoothing processing component, and a second radius determination component.

The first node determining component is configured to determine a plurality of first nodes that make up a path curve based on the current path, the associated nodes of the path nodes, and the second projection points.

The interpolation processing component is used for carrying out interpolation processing on the plurality of first nodes to obtain a plurality of second nodes.

The smoothing processing component is used for carrying out smoothing processing on the plurality of first nodes and the plurality of second nodes by utilizing a sliding time window method to obtain a path curve.

The second radius determination component is configured to determine a second radius based on the first radius if it is determined that the path node satisfies the local extremum condition.

According to an embodiment of the invention, the alternative node determining subunit comprises an alternative node determining component.

The alternative node determining component is configured to determine at least one alternative node located within a circular area centered on the path node and having a second radius as a radius from a plurality of nodes included in the current path.

According to an embodiment of the invention, the curve determination submodule comprises a curve determination unit.

The curve determining unit is used for obtaining a path curve related to the second plane based on the connection curve between the third projection point and the fourth projection point.

According to an embodiment of the present invention, the first determination module 710 includes a first grid determination sub-module, a start point determination sub-module, a second grid determination sub-module, and a target point determination sub-module.

The first grid determination submodule is used for determining at least one first grid related to the robot based on the position of the robot.

The starting point determining submodule is used for obtaining a starting point based on the coordinates of at least one first grid in a preset coordinate system respectively.

The second grid determination submodule is used for determining at least one second grid related to the target position based on the target position.

The target point determination submodule is used for obtaining target points based on the coordinates of at least one second grid in a preset coordinate system respectively.

Any number of the modules, sub-modules, units, sub-units, or at least part of the functionality of any number of the sub-units according to embodiments of the invention may be implemented in one module. Any one or more of the modules, sub-modules, units, sub-units according to embodiments of the present invention may be implemented as a split into multiple modules. Any one or more of the modules, sub-modules, units, sub-units according to embodiments of the invention may be implemented at least in part as hardware circuitry, such as a Field Programmable Gate Array (FPGA), programmable Logic Array (PLA), system-on-chip, system-on-substrate, system-on-package, application Specific Integrated Circuit (ASIC), or in hardware or firmware in any other reasonable manner of integrating or packaging circuitry, or in any one of, or in any suitable combination of, software, hardware, and firmware. Alternatively, one or more of the modules, sub-modules, units, sub-units according to embodiments of the invention may be at least partly implemented as computer program modules, which, when run, may perform the respective functions.

For example, any of the first, second, and third determination modules 710, 720, and 730 may be combined in one module/unit/sub-unit or any of them may be split into a plurality of modules/units/sub-units. Alternatively, at least some of the functionality of one or more of these modules/units/sub-units may be combined with at least some of the functionality of other modules/units/sub-units and implemented in one module/unit/sub-unit. According to an embodiment of the present invention, at least one of the first determination module 710, the second determination module 720, and the third determination module 730 may be implemented at least in part as a hardware circuit, such as a Field Programmable Gate Array (FPGA), a Programmable Logic Array (PLA), a system on a chip, a system on a substrate, a system on a package, an Application Specific Integrated Circuit (ASIC), or may be implemented in hardware or firmware in any other reasonable way of integrating or packaging the circuits, or in any one of or a suitable combination of three of software, hardware, and firmware. Alternatively, at least one of the first determination module 710, the second determination module 720, and the third determination module 730 may be at least partially implemented as a computer program module, which when executed, may perform the corresponding functions.

It should be noted that, in the embodiment of the present invention, the path determining device portion corresponds to the path determining method portion in the embodiment of the present invention, and the description of the path determining device portion specifically refers to the path determining method portion, which is not described herein.

Fig. 8 schematically shows a block diagram of an electronic device adapted to implement a path determination method according to an embodiment of the invention. The electronic device shown in fig. 8 is only an example and should not be construed as limiting the functionality and scope of use of the embodiments of the invention.

As shown in fig. 8, the computer electronic device 800 according to the embodiment of the present invention includes a processor 801 that can perform various appropriate actions and processes according to a program stored in a read only memory ROM802 or a program loaded from a storage section 808 into a random access memory RAM 803. The processor 801 may include, for example, a general purpose microprocessor (e.g., a CPU), an instruction set processor and/or an associated chipset and/or special purpose microprocessor (e.g., an Application Specific Integrated Circuit (ASIC)), or the like. The processor 801 may also include on-board memory for caching purposes. The processor 801 may comprise a single processing unit or multiple processing units for performing the different actions of the method flows according to embodiments of the invention.

In the RAM 803, various programs and data required for the operation of the electronic device 800 are stored. The processor 801, the ROM 802, and the RAM 803 are connected to each other by a bus 804. The processor 801 performs various operations of the method flow according to the embodiment of the present invention by executing programs in the ROM 802 and/or the RAM 803. Note that the program may be stored in one or more memories other than the ROM 802 and the RAM 803. The processor 801 may also perform various operations of the method flow according to embodiments of the present invention by executing programs stored in the one or more memories.

According to an embodiment of the invention, the electronic device 800 may further comprise an input/output (I/O) interface 805, the input/output (I/O) interface 805 also being connected to the bus 804. The electronic device 800 may also include one or more of the following components connected to an input/output (I/O) interface 805: an input portion 806 including a keyboard, mouse, etc.; an output portion 807 including a display such as a Cathode Ray Tube (CRT), a Liquid Crystal Display (LCD), and a speaker; a storage section 808 including a hard disk or the like; and a communication section 809 including a network interface card such as a LAN card, a modem, or the like. The communication section 809 performs communication processing via a network such as the internet. The drive 810 is also connected to an input/output (I/O) interface 805 as needed. A removable medium 811 such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, or the like is mounted on the drive 810 as needed so that a computer program read out therefrom is mounted into the storage section 808 as needed.

According to an embodiment of the present invention, the method flow according to an embodiment of the present invention may be implemented as a computer software program. For example, embodiments of the present invention include a computer program product comprising a computer program embodied on a computer readable storage medium, the computer program comprising program code for performing the method shown in the flowcharts. In such an embodiment, the computer program may be downloaded and installed from a network via the communication section 809, and/or installed from the removable media 811. The above-described functions defined in the system of the embodiment of the present invention are performed when the computer program is executed by the processor 801. The systems, devices, apparatus, modules, units, etc. described above may be implemented by computer program modules according to embodiments of the invention.

The present invention also provides a computer-readable storage medium that may be embodied in the apparatus/device/system described in the above embodiments; or may exist alone without being assembled into the apparatus/device/system. The computer-readable storage medium carries one or more programs which, when executed, implement methods in accordance with embodiments of the present invention.

According to an embodiment of the present invention, the computer-readable storage medium may be a nonvolatile computer-readable storage medium. Examples may include, but are not limited to: a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

For example, according to embodiments of the invention, the computer-readable storage medium may include ROM 802 and/or RAM 803 and/or one or more memories other than ROM 802 and RAM 803 described above.

Embodiments of the present invention also include a computer program product comprising a computer program comprising program code for performing the method provided by the embodiments of the present invention, when the computer program product is run on an electronic device, for causing the electronic device to implement the path determining method provided by the embodiments of the present invention.

The above-described functions defined in the system/apparatus of the embodiment of the present invention are performed when the computer program is executed by the processor 801. The systems, apparatus, modules, units, etc. described above may be implemented by computer program modules according to embodiments of the invention.

In one embodiment, the computer program may be based on a tangible storage medium such as an optical storage device, a magnetic storage device, or the like. In another embodiment, the computer program may also be transmitted, distributed, and downloaded and installed in the form of a signal on a network medium, and/or from a removable medium 811 via a communication portion 809. The computer program may include program code that may be transmitted using any appropriate network medium, including but not limited to: wireless, wired, etc., or any suitable combination of the foregoing.

According to embodiments of the present invention, program code for carrying out computer programs provided by embodiments of the present invention may be written in any combination of one or more programming languages, and in particular, such computer programs may be implemented in high-level procedural and/or object-oriented programming languages, and/or in assembly/machine languages. Programming languages include, but are not limited to, such as Java, c++, python, "C" or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, partly on a remote computing device, or entirely on the remote computing device or server. In the case of remote computing devices, the remote computing device may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computing device (e.g., connected via the Internet using an Internet service provider).

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams or flowchart illustration, and combinations of blocks in the block diagrams or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. Those skilled in the art will appreciate that the features recited in the various embodiments of the invention and/or in the claims may be combined in various combinations and/or combinations even if such combinations or combinations are not explicitly recited in the invention. In particular, the features recited in the various embodiments of the invention and/or in the claims can be combined in various combinations and/or combinations without departing from the spirit and teachings of the invention. All such combinations and/or combinations fall within the scope of the invention.

The embodiments of the present invention are described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Although the embodiments are described above separately, this does not mean that the measures in the embodiments cannot be used advantageously in combination. The scope of the invention is defined by the appended claims and equivalents thereof. Various alternatives and modifications can be made by those skilled in the art without departing from the scope of the invention, and such alternatives and modifications are intended to fall within the scope of the invention.

Claims

1. A method of path determination, comprising:

responding to a path determination request, determining a starting point of a position of a robot in a preset coordinate system and a target point of a target position included in the path determination request in the preset coordinate system, wherein the preset coordinate system is determined based on a closed space in which the robot is positioned, and at least one obstacle object is included in the closed space;

path planning is carried out based on projections of the starting point, the target point, the closed space and the at least one obstacle object in a plurality of orthogonal planes, so as to obtain path curves related to the orthogonal planes, wherein the orthogonal planes are determined based on the preset coordinate system; and

Obtaining a target path from the position of the robot to the target position based on path curves related to the orthogonal planes respectively;

the plurality of orthogonal planes comprise at least one first plane and at least one second plane, wherein an included angle between the first plane and a target plane is smaller than a preset angle, and the target plane comprises the connecting surfaces of the closed space and the at least one obstacle object;

the path planning is performed based on the projection of the starting point, the target point, the closed space and the at least one obstacle object in a plurality of orthogonal planes, so as to obtain path curves related to the orthogonal planes, and the path planning comprises the following steps:

taking a first projection area of the closed space on the first plane and a second projection area of the at least one obstacle object on the first plane as constraints, and carrying out path planning based on a first projection point of the starting point on the first plane and a second projection point of the target point on the first plane to obtain a path curve related to the first plane; and

And for the second plane, obtaining a path curve related to the second plane based on a third projection point of the starting point on the second plane and a fourth projection point of the target point on the second plane.

2. The method according to claim 1, wherein the performing path planning based on the first projection point of the starting point on the first plane and the second projection point of the target point on the first plane with the first projection area of the closed space on the first plane and the second projection area of the at least one obstacle object on the first plane as constraints, to obtain a path curve related to the first plane includes:

generating a repulsive force field of the first plane based on the first projection region and the second projection region;

generating a gravitational field of the first plane based on the second projection point; and

and carrying out path planning by utilizing a progressive optimal fast random search tree method based on the repulsive field and the gravitational field to obtain a path curve between the first projection point and the second projection point.

3. The method according to claim 2, wherein the path planning using a progressive optimal fast random search tree method based on the repulsive field and the gravitational field to obtain a path curve between the first projection point and the second projection point comprises:

Determining a sampling point in the first plane based on a leaf node of a current path, the repulsive field and the gravitational field, wherein a root node of the current path is the first projection point;

generating path nodes in the first plane based on a preset step length along the direction from the leaf node of the current path to the sampling point;

determining at least one alternative node which is positioned in a circular area taking the path node as a center and taking a first radius as a radius from a plurality of nodes included in the current path;

determining an associated node of the path node based on path costs between the path node and each of the at least one candidate node;

obtaining the path curve based on the current path, the associated node of the path node, the path node and the second projection point when the distance between the path node and the second projection point is smaller than or equal to the preset step length; and

and under the condition that the distance between the path node and the second projection point is larger than the preset step length, obtaining a new current path based on the associated node of the path node and the current path.

4. A method according to claim 3, wherein said deriving the path curve based on the current path, the associated node of the path node, the path node and the second proxel comprises:

determining a plurality of first nodes constituting the path curve based on the current path, the associated nodes of the path nodes, the path nodes and the second projection points;

performing interpolation processing on the plurality of first nodes to obtain a plurality of second nodes; and

and smoothing the plurality of first nodes and the plurality of second nodes by utilizing a sliding time window method to obtain the path curve.

5. A method according to claim 3, characterized in that the method further comprises:

determining a second radius based on the first radius if it is determined that the path node satisfies a local extremum condition;

wherein the determining at least one candidate node located in a circular area with the path node as a center and a first radius as a radius from a plurality of nodes included in the current path includes:

and determining at least one alternative node which is positioned in a circular area taking the path node as a center and taking the second radius as a radius from a plurality of nodes included in the current path.

6. The method according to claim 1, wherein the obtaining a path curve associated with the second plane based on a third projection point of the start point on the second plane and a fourth projection point of the target point on the second plane includes:

and obtaining a path curve related to the second plane based on the connection curve between the third projection point and the fourth projection point.

7. The method of claim 1, wherein the enclosed space is divided into a plurality of grids;

the determining a starting point of the position of the robot in a preset coordinate system and a target point of the target position included in the path determination request in the preset coordinate system includes:

determining at least one first grid associated with the robot based on the location of the robot;

obtaining the starting point based on the coordinates of each of the at least one first grid in the preset coordinate system;

determining at least one second grid associated with the target location based on the target location; and

and obtaining the target point based on the coordinates of each of the at least one second grid in the preset coordinate system.

8. The method according to any one of claim 1 to 7, wherein,

the closed space comprises an internal cavity of the transformer;

the at least one obstacle object comprises at least one winding inside the transformer.

9. A path determining apparatus, comprising:

a first determining module, configured to determine, in response to a path determining request, a starting point of a position where a robot is located in a preset coordinate system and a target point of a target position included in the path determining request in the preset coordinate system, where the preset coordinate system is determined based on a closed space where the robot is located, and the closed space includes at least one obstacle object;

the second determining module is used for planning a path based on projections of the starting point, the target point, the closed space and the at least one obstacle object in a plurality of orthogonal planes respectively to obtain path curves related to the orthogonal planes respectively, wherein the orthogonal planes are determined based on the preset coordinate system;

a third determining module, configured to obtain a target path from a position where the robot is located to the target position based on path curves related to each of the plurality of orthogonal planes;

wherein the second determining module includes:

the path planning submodule is used for carrying out path planning on the first plane by taking a first projection area of the closed space on the first plane and a second projection area of each of the at least one obstacle object on the first plane as constraints and based on a first projection point of the starting point on the first plane and a second projection point of the target point on the first plane to obtain a path curve related to the first plane; and

and the curve determination submodule is used for obtaining a path curve related to the second plane based on a third projection point of the starting point on the second plane and a fourth projection point of the target point on the second plane.