Turn-around path optimization method based on Archimedes spiral motion model

Abstract

The invention relates to a U-turn path optimization method and system based on an Archimedes spiral motion model, computer equipment and a storage medium. The method comprises the following steps: establishing a ground coordinate system, acquiring coordinates of a target moving object relative to an original point, and judging whether the target moving object collides on a moving path or not by adopting a vector product method; determining a turning-around area of the target moving object based on the ground coordinate system; an Archimedes spiral model is established in combination with the U-turn area of the target moving object, and a U-turn path of the target moving object is determined, wherein the U-turn path of the target moving object comprises a first arc and a second arc which are tangent to the Archimedes spiral; and establishing a single-target optimization model by taking the minimum length of the U-turn path as an objective function and taking the tangent relation of each arc as a constraint condition, and solving and outputting the shortest U-turn path of the target moving object. By the adoption of the method, on the premise that no collision is achieved, the U-turn path can be optimized, the needed space is reduced, and the path smoothness is improved.

Description

Technical Field

[0001] The present application relates to the technical field of automated control and path planning, and in particular to a U-turn path optimization method, system, computer device and storage medium based on an Archimedean spiral motion model. Background Art

[0002] In urban transportation systems, vehicle U-turn path planning and U-turn problems are common technical difficulties, especially in limited spaces such as narrow streets, parking lots or bus stops. How to design the optimal U-turn path without causing collisions is directly related to the operating efficiency and safety of the public transportation system.

[0003] Traditional path planning methods usually include geometry-based path generation methods, search-based algorithms, etc. However, no matter whether it is a geometry method, a search algorithm or a biologically inspired algorithm, it is easy to fall into a local optimal solution in path planning, resulting in the inability to find the global optimal path. In the face of dynamic traffic environments, the computational efficiency and response speed of traditional algorithms are often insufficient, making it difficult to meet the needs of buses for real-time path updates and obstacle avoidance during actual U-turns.

[0004] Therefore, in the path planning for a car turning around, how to avoid collisions, improve turning efficiency and ensure driving safety through reasonable path design within the limited road space is still a technical challenge that needs to be solved. Summary of the invention

[0005] Based on this, it is necessary to provide a U-turn path optimization method, system, computer equipment and storage medium based on the Archimedean spiral motion model that can solve the path planning and collision detection problems in complex environments in response to the above technical problems.

[0006] In a first aspect, the present application provides a U-turn path optimization method based on an Archimedean spiral motion model, comprising:

[0007] Step S1, establishing a ground coordinate system and obtaining the coordinates of the target moving object relative to the origin, and using a vector product method to determine whether the target moving object will collide on the moving path;

[0008] Step S2, when it is determined that the target moving object will collide on the moving path, determining a turning area of ​​the target moving object based on the ground coordinate system;

[0009] Step S3, establishing an Archimedean spiral model in combination with the turning area of ​​the target moving object and determining the turning path of the target moving object, wherein the turning path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral;

[0010] Step S4, establishing a single-objective optimization model with the minimum length of the U-turn path as the objective function and the tangency of each arc as the constraint condition, solving and outputting the shortest U-turn path of the target moving object.

[0011] In one embodiment, determining the turning area of ​​the target moving object based on the ground coordinate system in step S2 includes:

[0012] Taking the position of the target moving object as the center of the circle, the distance between the target moving object and the adjacent moving object is set as the first distance, and the distance between the target moving object and the closest stationary object is set as the second distance; when the second distance is less than or equal to half of the first distance, the radius of the turning area of ​​the target moving object is the second distance; when the second distance is greater than half of the first distance, the radius of the turning area of ​​the target moving object is half of the first distance.

[0013] In one embodiment, the turning path of the target moving object in step S3 includes a first arc and a second arc tangent to the Archimedean spiral, including:

[0014] The turning path of the target moving object consists of a first circular arc and a second circular arc that are tangent to each other, wherein the radius of the first circular arc is twice the radius of the second circular arc, and both the first circular arc and the second circular arc are tangent to the Archimedean spiral.

[0015] In one embodiment, in step S3, establishing an Archimedean spiral model in combination with the turning area of ​​the target moving object and determining the turning path of the target moving object includes:

[0016] According to the definition of Archimedean screw, the Archimedean screw parameter equation is obtained, wherein the parameters of the Archimedean screw parameter equation include the initial radius, pitch and angle of the Archimedean screw and the increment of the radius of each turn of the Archimedean screw;

[0017] The initial turning point and the final turning point where the turning path is tangent to the Archimedean spiral are determined, and the turning path of the target moving object is generated based on the radius of the first arc being twice the radius of the second arc and the turning area of ​​the target moving object.

[0018] In one embodiment, step S3 further includes:

[0019] According to the Archimedean screw parameter equation and the coordinates of the initial turning point, the equation of the tangent line tangent to the turning path and the equation of the straight line perpendicular to the two tangent lines are obtained;

[0020] Obtain the distance between the initial U-turn point and the final U-turn point according to the coordinates of the initial U-turn point and the final U-turn point;

[0021] The sum of the radius of the first arc and the radius of the second arc is obtained according to the tangent equation, the equation of the straight line perpendicular to the two tangents, and the distance between the initial turning point and the final turning point.

[0022] In one embodiment, the objective function in step S4 is the sum of the product of the radius of the first arc and the corresponding center angle and the product of the radius of the second arc and the corresponding center angle.

[0023] In one embodiment, solving and outputting the shortest turning path of the target moving object in step S4 includes:

[0024] The variable step enumeration method is adopted to shorten the length of the U-turn path by adjusting the radii of the first arc and the second arc, and the shortest U-turn path of the target moving object is determined and output.

[0025] In a second aspect, the present application also provides a U-turn path optimization system based on the Archimedean spiral motion model, comprising:

[0026] The collision detection module is used to establish a ground coordinate system and obtain the coordinates of the target moving object relative to the origin, and use the vector product method to determine whether the target moving object will collide on the moving path;

[0027] A U-turn area determination module, used to determine the U-turn area of ​​the target moving object based on the ground coordinate system when it is determined that the target moving object will collide on the moving path;

[0028] An Archimedean spiral trajectory generation module is used to establish an Archimedean spiral model in combination with the turning area of ​​the target moving object and determine the turning path of the target moving object, wherein the turning path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral;

[0029] The shortest U-turn path generation module is used to establish a single-objective optimization model with the minimum length of the U-turn path as the objective function and the tangency of each arc as the constraint condition, and to solve and output the shortest U-turn path of the target moving object.

[0030] In a third aspect, the present application further provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of a U-turn path optimization method based on an Archimedean spiral motion model when executing the computer program.

[0031] In a fourth aspect, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of a U-turn path optimization method based on an Archimedean spiral motion model.

[0032] The above-mentioned U-turn path optimization method, system, computer device and storage medium based on the Archimedean spiral motion model establish a ground coordinate system and obtain the coordinates of the target moving object relative to the origin, and use the vector product method to determine whether the target moving object will collide on the moving path; when it is determined that the target moving object will collide on the moving path, the U-turn area of ​​the target moving object is determined based on the ground coordinate system; the Archimedean spiral model is established in combination with the U-turn area of ​​the target moving object and the U-turn path of the target moving object is determined, wherein the U-turn path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral; a single-objective optimization model is established with the minimum length of the U-turn path as the objective function and each arc maintaining a tangent relationship as a constraint condition, and the shortest U-turn path of the target moving object is solved and output; by introducing the Archimedean spiral model and its tangent relationship with the arc, the method can optimize the U-turn path, reduce the required space and improve the path smoothness under the premise of meeting the collision-free condition. The method can be applied to buses, automatic driving and various types of automated trajectory planning systems, and is particularly suitable for path planning and U-turn operations of multi-body systems. This application adopts the Archimedean spiral motion model for path planning, and combines it with an improved particle swarm algorithm to effectively deal with trajectory planning and real-time obstacle avoidance problems in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 1 is a flow chart of a U-turn path optimization method based on an Archimedean spiral motion model in one embodiment;

[0034] Figure 2 A schematic diagram of a bus U-turn path in one embodiment;

[0035] Figure 3 A schematic diagram of solving a bus turn path in an embodiment. DETAILED DESCRIPTION

[0036] In automated systems, bus turn path planning and turn problems are common technical challenges, especially in narrow roads or limited parking spaces in cities. How to design the optimal turn path without collision is directly related to the operational efficiency and safety of the bus system. In traditional path planning technology, geometric methods or heuristic search algorithms are usually used to achieve path planning, but in complex multi-body motion, there are still many shortcomings in how to ensure the smoothness of the turn path, reduce the required space, and improve safety.

[0037] Traditional path planning methods usually include geometry-based path generation methods, search-based algorithms, etc. Whether it is a geometric method, a search algorithm or a bio-inspired algorithm, it is easy to fall into a local optimal solution in path planning, resulting in the inability to find the global optimal path. When dealing with dynamic obstacles, the computational efficiency and response speed of traditional algorithms are insufficient, and it is difficult to meet the needs of real-time path updates. Especially in busy urban roads and parking lots, traditional methods are difficult to effectively cope with complex dynamic traffic environments. In order to solve these problems, this application proposes a bus turn-around path optimization method based on the Archimedean spiral motion model. This method not only ensures the design of the global optimal path, but also realizes real-time collision detection and path optimization.

[0038] The Archimedean spiral model has gradually attracted more and more attention due to its unique geometric properties. It can not only ensure the smoothness of the motion, but also achieve global path optimization by adjusting parameters. However, for the problem of bus U-turn path optimization, there are relatively few studies on the combination of the Archimedean spiral and the traditional circular arc path. This application is aimed at this problem. By introducing the tangent relationship between the Archimedean spiral and the circular arc path, the precise control of the bus U-turn path is achieved, and the space required for the U-turn path is minimized while ensuring that the bus does not collide.

[0039] The U-turn path optimization method based on the Archimedean spiral motion model provided in this application is intended to solve the U-turn path planning problem of buses in a narrow space. By introducing the Archimedean spiral model and tangent to two arcs, it is ensured that the bus can successfully complete the U-turn in a limited road or parking lot. In the optimization process, the U-turn path is minimized as the goal, combined with the collision detection model, the arc radius is dynamically adjusted, and finally the shortest and safe U-turn path is obtained. This method can not only improve the U-turn efficiency of buses in urban environments, but also ensure vehicle safety under complex traffic conditions.

[0040] This application belongs to the field of automatic control and path planning technology, and particularly relates to path planning and U-turn path optimization of complex multi-body systems in urban transportation. This technology can be widely used in autonomous driving buses, bus U-turns and obstacle avoidance tasks in intelligent transportation systems, and help improve the operating efficiency and safety of urban public transportation systems.

[0041] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described are only used to explain the present application and are not used to limit the scope of the present application.

[0042] In an exemplary embodiment, Figure 1 As shown, a U-turn path optimization method based on the Archimedean spiral motion model is provided, comprising:

[0043] Step S1, establishing a ground coordinate system and obtaining the coordinates of the target moving object relative to the origin, and using a vector product method to determine whether the target moving object will collide on the moving path;

[0044] Step S2, when it is determined that the target moving object will collide on the moving path, determining a turning area of ​​the target moving object based on the ground coordinate system;

[0045] Step S3, establishing an Archimedean spiral model in combination with the turning area of ​​the target moving object and determining the turning path of the target moving object, wherein the turning path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral;

[0046] Step S4, establishing a single-objective optimization model with the minimum length of the U-turn path as the objective function and the tangency of each arc as the constraint condition, solving and outputting the shortest U-turn path of the target moving object.

[0047] Specifically, the Archimedean spiral motion model uses the Archimedean spiral as the motion trajectory of the moving body, wherein the Archimedean spiral motion model is the Archimedean spiral model, and its polar coordinate equation is shown in formula (1):

[0048] r=r0+k·θ (1)

[0049] Among them, r0 is the initial radius, k is the pitch, and θ is the moving angle of the moving body. This equation shows that as the angle increases, the moving body moves along the Archimedean spiral trajectory, ensuring the smoothness of the trajectory and optimal use of space.

[0050] Furthermore, in the arc design of the U-turn path, an S-shaped path with two tangent arcs is designed. The radius ratio of the front and rear arcs is 2:1, that is, the radius ratio of the first arc to the second arc is 2:1, and they are tangent to the Archimedean spiral. The tangent point of the arc and the spiral is determined through geometric calculation, and the path of the entire U-turn process is ensured to be smooth and without mutations.

[0051] Furthermore, collision detection and path optimization are performed; through geometric analysis, it is determined whether the moving body collides. In this embodiment, an improved particle swarm optimization algorithm is used, with the minimum pitch as the objective function, a single-objective optimization model is established, and path parameters are dynamically adjusted to ensure that path planning is completed without collision.

[0052] Furthermore, the U-turn path optimization process is to dynamically adjust the path parameters by optimizing the target and the collision detection model, and output the optimal U-turn path.

[0053] In one embodiment, taking the U-turn of a city bus as an example, the bus needs to complete the U-turn in limited spaces such as narrow streets and parking lots. When there are a large number of buses and the traffic environment is complex, the risk of collision during the U-turn will also increase. Therefore, reasonable planning of the bus's driving path, especially the design of the U-turn area, can reduce the space occupied by the vehicle when turning around, maintain the stability of the U-turn process, and avoid passenger discomfort or vehicle damage caused by sharp turns. The present application proposes a method of selecting a U-turn path for a bus, in which two arcs are tangent to the Archimedean spiral, aiming to achieve a U-turn within the specified U-turn space, make the U-turn path as short as possible, and ensure that no collision occurs during the U-turn process.

[0054] Specifically, consider the bus as the target moving object, and the schematic diagram of the U-turn path is as follows: Figure 2 As shown in the figure, the dotted circle area is the U-turn area. The solution process includes the following constraints: Constraint 1: The U-turn path consists of two tangent arcs; Constraint 2: The radius of the front arc is twice the radius of the rear arc, that is, the front arc is the first arc and the rear arc is the second arc.

[0055] The objective function is to minimize the arc length of the U-turn path, that is, to find the shortest U-turn path by optimizing the arc radius of the U-turn area. This method can not only effectively plan the U-turn path of the bus in a limited parking space, but also improve the safety and efficiency of the U-turn process, ensuring that the bus can successfully complete the U-turn in a complex urban environment.

[0056] In one embodiment, the objective function in step S4 is the sum of the product of the radius of the first arc and the corresponding center angle and the product of the radius of the second arc and the corresponding center angle.

[0057] For example, the specific objective function is shown in formula (2):

[0058]

[0059] Where S is the total arc length of the U-turn path, r i are the radii of the two arcs, θ i is the corresponding central angle.

[0060] Under the above two constraints, the objective function optimization scheme is optimized by traversing the radius of the U-turn area through the variable step size enumeration method, and gradually adjusting the radius value until the minimum path solution that meets the constraints is found.

[0061] Exemplarily, in the step where the main goal is collision detection, the vector product method is used to determine whether the target moving object will collide on the moving path. The coordinates of the bus vertices relative to the origin of the ground coordinate system are known, and the vector product method is used to determine whether a collision has occurred. The vector product determines the positional relationship of a point relative to a line segment by calculating the product of two vectors. A positive vector product indicates that the point is on the left, a negative vector product indicates that it is on the right, and a zero vector product indicates that the point is on the straight line. This method is widely used in geometric calculations, such as determining whether a point is inside a polygon or for collision detection of polygons. For a point, let point A = (x A ,y A ), B=(x B ,y B ), P is a point on another rectangle, let P = (x, y), then In the plane rectangular coordinate system oxy, the basis is {i, j}, which is expanded to a set of bases {i, j, k} of the space rectangular coordinate system oxyz. Then in the space rectangular coordinate system Then the vector product is as shown in formula (3):

[0062]

[0063] If P is on the left side of AB, the direction of the vector product is the same as the positive direction of the z-axis; if P is on the right side of AB, the direction of the vector product is the same as the negative direction of the z-axis; if P is on AB, then and If they are collinear, the vector product is 0. Therefore, we only need to determine whether the bus vertex is behind its adjacent bus to determine whether a collision occurs.

[0064] In one embodiment, determining the turning area of ​​the target moving object based on the ground coordinate system in step S2 includes:

[0065] Taking the position of the target moving object as the center of the circle, the distance between the target moving object and the adjacent moving object is set as the first distance, and the distance between the target moving object and the closest stationary object is set as the second distance; when the second distance is less than or equal to half of the first distance, the radius of the turning area of ​​the target moving object is the second distance; when the second distance is greater than half of the first distance, the radius of the turning area of ​​the target moving object is half of the first distance.

[0066] For example, the bus turning area is determined, that is, the location of the bus is taken as the center of the circle, and the distance between two adjacent buses is a, that is, the first distance; the distance between the bus and the nearest object in the warehouse is b, that is, the second distance; then if The radius of the turning area is y; otherwise, The radius of the turning area is

[0067] In one embodiment, the turning path of the target moving object in step S3 includes a first arc and a second arc tangent to the Archimedean spiral, including:

[0068] The turning path of the target moving object consists of a first circular arc and a second circular arc that are tangent to each other, wherein the radius of the first circular arc is twice the radius of the second circular arc, and both the first circular arc and the second circular arc are tangent to the Archimedean spiral.

[0069] In one embodiment, in step S3, establishing an Archimedean spiral model in combination with the turning area of ​​the target moving object and determining the turning path of the target moving object includes:

[0070] According to the definition of Archimedean screw, the Archimedean screw parameter equation is obtained, wherein the parameters of the Archimedean screw parameter equation include the initial radius, pitch and angle of the Archimedean screw and the increment of the radius of each turn of the Archimedean screw;

[0071] The initial turning point and the final turning point where the turning path is tangent to the Archimedean spiral are determined, and the turning path of the target moving object is generated based on the radius of the first arc being twice the radius of the second arc and the turning area of ​​the target moving object.

[0072] For example, an equidistant spiral model is established to determine the bus turning path. According to the definition of the equidistant spiral, its parameter equation is shown in formula (4):

[0073]

[0074] Where r0 is the initial radius of 0, k is the pitch, and θ is the angle. Here a is a constant, which represents the increment of the radius of each turn of the spiral. The equation of the equidistant spiral symmetrical about the origin is shown in formula (5):

[0075] r(θ)=a·(θ+π) (5)

[0076] The size of the pitch can be determined based on the tangency conditions of each arc and the geometric relationship. It is known that the "S"-shaped path of the U-turn is tangent to the spiral motion trajectory at the initial U-turn point C, and the radius of the first arc is twice that of the second arc, that is, the U-turn path of the target moving object is composed of the tangent first arc and second arc, where the radius of the first arc is twice the radius of the second arc, and both the first arc and the second arc are tangent to the Archimedean spiral. From this, the equidistant spiral motion trajectory of the bus about the U-turn can be drawn.

[0077] In one embodiment, step S3 further includes:

[0078] According to the Archimedean screw parameter equation and the coordinates of the initial turning point, the equation of the tangent line tangent to the turning path and the equation of the straight line perpendicular to the two tangent lines are obtained;

[0079] Obtain the distance between the initial U-turn point and the final U-turn point according to the coordinates of the initial U-turn point and the final U-turn point;

[0080] The sum of the radius of the first arc and the radius of the second arc is obtained according to the tangent equation, the equation of the straight line perpendicular to the two tangents, and the distance between the initial turning point and the final turning point.

[0081] The bus turn path calculation solution is as follows Figure 3 As shown in the figure, O1 and O2 represent the centers of the two arcs in the figure, O1 is the center of the first arc, and O2 is the center of the second arc; CD is a straight line passing through the first arc origin O1 (i.e., the first arc center O1) and perpendicular to the tangent passing through point C, r'1, r'2 represent the radius of the two arcs and satisfy r'1=2r'2, where r'1 is the radius of the first arc, and r'2 is the radius of the second arc; θ1 is the angle between the first arc and the straight line CD, and θ2 is the angle between the straight line connecting r'1 and r'2 and the straight line CD. C is the initial turning point, and B is the final turning point.

[0082] For example, according to the equidistant spiral equation and C(x c ,y c ) coordinates, and the tangent equation of the "S"-shaped path tangent to it is obtained as shown in formula (6):

[0083]

[0084] Since the two arcs of the U-turn path are tangent to the equidistant spiral, the two tangent equations can be deduced to be parallel based on the properties of the equidistant spiral, and the equation of the other tangent can be obtained. Since CD is perpendicular to the two tangents, formula (7) can be obtained:

[0085] CD=2Rcosθ1 (7)

[0086] Where R is the radius of the turning space, and because CD passes through point C, the equation of the CD line is shown in formula (8):

[0087]

[0088] Given the coordinates of point C and point B, the straight-line distance d1 between points C and B can be obtained as shown in formula (9):

[0089]

[0090] Similarly, if the coordinates of the endpoints are known, the lengths of CD, BD, and BC can be calculated using the distance formula. Using the cosine theorem, the angle of θ1 is shown in formula (10):

[0091] 2BC·CD cos θ1=BC 2 +CD 2 -BD 2 (10)

[0092] According to the relationship between the internal and external angles of a triangle, the angle between the straight line CD and the straight line connecting r′1 and r′2 is twice the internal angle θ1, that is, θ2 = 2θ1. According to the above relationship and conditions, (r′1 + r′2) sinθ2 = 2Rsinθ1, and we can obtain:

[0093]

[0094] In one embodiment, solving and outputting the shortest turning path of the target moving object in step S4 includes:

[0095] The variable step enumeration method is adopted to shorten the length of the U-turn path by adjusting the radii of the first arc and the second arc, and the shortest U-turn path of the target moving object is determined and output.

[0096] For example, the shortest U-turn path is calculated; that is, the minimum length of the U-turn path is taken as the objective function, and the tangent relationship between the arcs is maintained as the constraint condition, and a single-objective optimization model is established. The variable step enumeration method is adopted to shorten the length of the U-turn path by adjusting the radius of the first arc and the second arc, and the shortest U-turn path of the target moving object is determined and output; that is, the radius of the arc is adjusted to shorten the U-turn path using the variable step enumeration method, and the shortest U-turn path is finally determined. According to the different results R detected, the radius of the U-turn curve is adjusted in time, so as to successfully complete the U-turn and reduce the possibility of collision.

[0097] The trajectory planning and collision detection method and system based on the Archimedean spiral motion model proposed in this application solves the path planning and collision detection problems in complex environments. Through the improved particle swarm optimization algorithm, efficient and accurate path optimization is achieved. The system can be widely used in bus navigation, automatic driving, drone control and other fields, with good practical value and promotion prospects.

[0098] In this specification, the use of terms such as "embodiment", "specific embodiment" or "certain embodiments" is intended to indicate that specific features, materials, structures or characteristics described in conjunction with these embodiments or examples are used in at least one embodiment of the present invention. However, exemplary statements of terms do not necessarily refer to the same embodiment. In addition, the specific features, materials, structures or characteristics described herein may be combined in any appropriate manner in one or more embodiments.

[0099] Although the embodiments of the present application have been described in detail, those skilled in the art should understand that these embodiments may be modified, replaced or subjected to various deformations without departing from the basic principles and spirit of the present invention. The scope of protection of the present invention shall be based on the scope of the attached claims and their equivalent technical features.

[0100] At least a portion of the steps in the flowcharts involved in the embodiments described above may include multiple steps or multiple stages. These steps or stages may be executed at different times, or may be executed in turn or alternation with other steps or at least a portion of the steps or stages in other steps.

[0101] Based on the same inventive concept, the embodiment of the present application also provides a U-turn path optimization system based on the Archimedean spiral motion model for implementing the U-turn path optimization method based on the Archimedean spiral motion model involved above. The implementation scheme for solving the problem provided by the system is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more U-turn path optimization system embodiments based on the Archimedean spiral motion model provided below can refer to the limitations of the U-turn path optimization method based on the Archimedean spiral motion model above, and will not be repeated here.

[0102] In an exemplary embodiment, a U-turn path optimization system based on an Archimedean spiral motion model is provided, comprising:

[0103] The collision detection module is used to establish a ground coordinate system and obtain the coordinates of the target moving object relative to the origin, and use the vector product method to determine whether the target moving object will collide on the moving path;

[0104] A U-turn area determination module, used to determine the U-turn area of ​​the target moving object based on the ground coordinate system when it is determined that the target moving object will collide on the moving path;

[0105] An Archimedean spiral trajectory generation module is used to establish an Archimedean spiral model in combination with the turning area of ​​the target moving object and determine the turning path of the target moving object, wherein the turning path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral;

[0106] The shortest U-turn path generation module is used to establish a single-objective optimization model with the minimum length of the U-turn path as the objective function and the tangency of each arc as the constraint condition, and to solve and output the shortest U-turn path of the target moving object.

[0107] Specifically, the trajectory generated by the Archimedean spiral trajectory generation module is:

[0108] r=r0+k·θ (1)

[0109] Among them, r0 is the initial radius, k is the pitch, and θ is the angle.

[0110] Furthermore, the collision detection module can determine in real time whether a collision occurs between moving objects and dynamically adjust path parameters according to the detection results.

[0111] In another embodiment, a U-turn path optimization and collision detection system based on Archimedean spiral is provided, comprising: a real-time collision detection module; an Archimedean spiral trajectory generation module; an improved particle swarm optimization algorithm module; and an output module. The real-time collision detection module is the collision detection module, and the shortest U-turn path generation module includes an improved particle swarm optimization algorithm module and an output module.

[0112] Each module in the above-mentioned U-turn path optimization system based on the Archimedean spiral motion model can be implemented in whole or in part by software, hardware, or a combination thereof. Each of the above-mentioned modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each of the above modules.

[0113] In one embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiments when executing the computer program.

[0114] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0115] For those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these modifications and improvements are all within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the attached claims.

Claims

1. A U-turn path optimization method based on the Archimedean spiral motion model, characterized in that: The method is used to perform path planning on a target moving object to generate a shortest turning path, comprising: Step S1, establishing a ground coordinate system and obtaining the coordinates of the target moving object relative to the origin, and using a vector product method to determine whether the target moving object will collide on the moving path; Step S2, when it is determined that the target moving object will collide on the moving path, determining a turning area of ​​the target moving object based on the ground coordinate system; Step S3, establishing an Archimedean spiral model in combination with the turning area of ​​the target moving object and determining the turning path of the target moving object, wherein the turning path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral; Step S4, establishing a single-objective optimization model with the minimum length of the U-turn path as the objective function and the tangency of each arc as the constraint condition, solving and outputting the shortest U-turn path of the target moving object.

2. The method according to claim 1, characterized in that Determining the turning area of ​​the target moving object based on the ground coordinate system in step S2 includes: Taking the position of the target moving object as the center of the circle, the distance between the target moving object and the adjacent moving object is set as the first distance, and the distance between the target moving object and the closest stationary object is set as the second distance; when the second distance is less than or equal to half of the first distance, the radius of the turning area of ​​the target moving object is the second distance; when the second distance is greater than half of the first distance, the radius of the turning area of ​​the target moving object is half of the first distance.

3. The method according to claim 2, characterized in that The turning path of the target moving object in step S3 includes a first arc and a second arc tangent to the Archimedean spiral, including: The turning path of the target moving object consists of a first circular arc and a second circular arc that are tangent to each other, wherein the radius of the first circular arc is twice the radius of the second circular arc, and both the first circular arc and the second circular arc are tangent to the Archimedean spiral.

4. The method according to claim 3, characterized in that The step S3 of establishing an Archimedean spiral model in combination with the turning area of ​​the target moving object and determining the turning path of the target moving object includes: According to the definition of Archimedean screw, the Archimedean screw parameter equation is obtained, wherein the parameters of the Archimedean screw parameter equation include the initial radius, pitch and angle of the Archimedean screw and the increment of the radius of each turn of the Archimedean screw; The initial turning point and the final turning point where the turning path is tangent to the Archimedean spiral are determined, and the turning path of the target moving object is generated based on the radius of the first arc being twice the radius of the second arc and the turning area of ​​the target moving object.

5. The method according to claim 4, characterized in that After step S3, the following steps are also included: According to the Archimedean screw parameter equation and the coordinates of the initial turning point, the equation of the tangent line tangent to the turning path and the equation of the straight line perpendicular to the two tangent lines are obtained; Obtain the distance between the initial U-turn point and the final U-turn point according to the coordinates of the initial U-turn point and the final U-turn point; The sum of the radius of the first arc and the radius of the second arc is obtained according to the tangent equation, the equation of the straight line perpendicular to the two tangents, and the distance between the initial turning point and the final turning point.

6. The method according to claim 5, characterized in that In step S4, the objective function is the sum of the product of the radius of the first arc and the corresponding center angle and the product of the radius of the second arc and the corresponding center angle.

7. The method according to claim 6, characterized in that Solving and outputting the shortest turning path of the target moving object in step S4 includes: The variable step enumeration method is adopted to shorten the length of the U-turn path by adjusting the radii of the first arc and the second arc, and the shortest U-turn path of the target moving object is determined and output.

8. A U-turn path optimization system based on the Archimedean spiral motion model, characterized in that: The system comprises: The collision detection module is used to establish a ground coordinate system and obtain the coordinates of the target moving object relative to the origin, and use the vector product method to determine whether the target moving object will collide on the moving path; A U-turn area determination module, used to determine the U-turn area of ​​the target moving object based on the ground coordinate system when it is determined that the target moving object will collide on the moving path; An Archimedean spiral trajectory generation module is used to establish an Archimedean spiral model in combination with the turning area of ​​the target moving object and determine the turning path of the target moving object, wherein the turning path of the target moving object includes a first arc and a second arc tangent to the Archimedean spiral; The shortest U-turn path generation module is used to establish a single-objective optimization model with the minimum length of the U-turn path as the objective function and the tangency of each arc as the constraint condition, and to solve and output the shortest U-turn path of the target moving object.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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