Intelligent path planning method for marine unmanned system based on improved repulsive potential field for obstacle avoidance

Abstract

The present invention relates to the technical field of unmanned boat path planning, and specifically to an intelligent path planning method for a marine unmanned system based on an improved repulsive potential field for obstacle avoidance, comprising: establishing an artificial potential field of the working environment of a surface unmanned boat; constructing a virtual environment repulsive potential field coordinate system; establishing a virtual environment repulsive potential field; establishing a velocity repulsive potential field; and performing path planning for the surface unmanned boat. The present invention introduces a virtual environment repulsive potential field for static obstacles and a velocity repulsive potential field for dynamic obstacles, so that the unmanned boat can effectively avoid obstacles on the basis of a traditional artificial potential field method, and then obtain an optimal planning path.

Description

Technical Field

[0001] The invention relates to the technical field of unmanned boat path planning, and in particular to an intelligent path planning method for a marine unmanned system based on an obstacle avoidance improved repulsive potential field. Background Art

[0002] With the continuous advancement of science and technology, unmanned surface vehicles (USVs) are increasingly used in the fields of surface navigation and environmental monitoring. Unmanned vehicles can perform various tasks efficiently and accurately, especially in complex waters and changing environments, where path planning technology is particularly important. In the process of path planning for unmanned surface vehicles, finding an optimal navigation route to ensure that it can reach the target location safely and quickly, while avoiding obstacles and dangerous areas, is one of the key issues that need to be solved.

[0003] In the development history of path planning, there are now many planning algorithms used to solve the path planning problem of unmanned boats, such as traditional path planning methods such as A* algorithm, D* algorithm, artificial potential field method, genetic algorithm, and bee swarm algorithm; among these path planning methods, the artificial potential field method (APF) is widely used in path planning of mobile robots and surface unmanned boats due to its simplicity, intuitiveness and high computational efficiency.

[0004] However, the traditional artificial potential field method has some limitations in practical applications. For example, when the unmanned boat approaches an obstacle, the artificial potential field method is prone to produce a local minimum, which causes the unmanned boat to fail in path planning and cannot move forward. In addition, when the distance between the obstacle and the target point is too close at a certain moment in the unmanned boat path planning process, the unmanned boat will oscillate back and forth near the target point, and thus cannot reach the target point, resulting in the failure of the unmanned boat path planning.

[0005] Therefore, it is necessary to provide an intelligent path planning method for marine unmanned systems based on obstacle avoidance and improved repulsive potential field to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide an intelligent path planning method for marine unmanned systems based on an obstacle avoidance improved repulsive potential field to address the local minimum dilemma and target unreachability problems that occur in the path planning process of surface unmanned boats using the traditional artificial potential field method, so as to solve the existing problems.

[0007] The present invention provides an intelligent path planning method for an unmanned marine system based on an obstacle avoidance improved repulsive potential field, which adopts the following technical solutions, including:

[0008] Establishing an artificial potential field for the working environment of the surface unmanned boat, wherein the artificial potential field includes: a gravitational potential field and a repulsive potential field;

[0009] The unmanned boat is taken as the origin of the coordinate system, and the direction of the unmanned boat pointing to the mission target point is Axis direction, the direction perpendicular to the unmanned boat pointing to the mission target point is Axis direction, construct the virtual environment repulsive potential field coordinate system;

[0010] Obtaining the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system; establishing a virtual environment repulsive potential field along the tangent direction of the obstacle edge in the working environment of the surface unmanned boat according to the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system;

[0011] According to the velocity vectors corresponding to the unmanned boat and the dynamic obstacle, a velocity repulsion potential field is established in the working environment of the surface unmanned boat;

[0012] The virtual environment repulsive potential field and the velocity repulsive potential field are introduced into the artificial potential field to obtain the target artificial potential field, and the artificial potential field method is used to plan the path of the surface unmanned vehicle under the target artificial potential field to obtain the path trajectory of the surface unmanned vehicle.

[0013] Preferably, the expression of the gravitational potential field is:

[0014]

[0015] In the formula, Indicates the position of the unmanned surface vehicle The gravitational potential field at time ; represents the proportional gain parameter of the gravitational potential field; Indicates the location of the mission target point that the surface unmanned vehicle needs to reach; Indicates the position of the unmanned surface vehicle Go to the mission target location The square of the distance between .

[0016] Preferably, the expression of the repulsive potential field is:

[0017]

[0018] In the formula, Indicates the position of the unmanned surface vehicle The repulsive potential field at time represents the repulsion coefficient; Indicates the location of static obstacles; Indicates the distance between the surface unmanned vehicle and the static obstacle; Indicates the action radius of the preset repulsive potential field; Indicates the obstacle effect radius.

[0019] Preferably, the step of obtaining the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system is:

[0020] The virtual environment repulsive potential field coordinate system and the earth coordinate system are transformed, and the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are obtained.

[0021] Preferably, the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are:

[0022]

[0023] In the formula, Indicates the position coordinates of the static obstacle in the geodetic coordinate system; Represents the static position coordinates after the translation transformation of the geodetic coordinate system; Represents the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the position coordinates of the origin of the virtual environment repulsive potential field coordinate system in the earth coordinate system; The line connecting the unmanned boat to the mission target point and the geodetic coordinate system The angle of the axis.

[0024] Preferably, the expression of the virtual environment repulsive potential field is:

[0025]

[0026] In the formula, represents the repulsive potential field of the virtual environment; Represents the horizontal coordinate of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the ordinate of the static obstacle in the virtual environment repulsive potential field coordinate system; represents the virtual environment repulsion coefficient; Represents the virtual environment repulsive potential field coordinate system The angle between the positive direction of the axis and the vector pointing from the mission target point to the obstacle.

[0027] Preferably, the expression of the virtual environment repulsion is:

[0028]

[0029] In the formula, Represents virtual environment repulsion; represents the repulsive potential field of the virtual environment; represents the virtual environment repulsion coefficient; Indicates the distance between the unmanned boat and the static obstacle; Represents the radius of action of the repulsive potential field of the virtual environment; represents the gradient operator; Represents the repulsive potential field along the virtual environment The unit vector of the direction; is the distance between the unmanned boat and the mission target point, It is a preset condition parameter, which is used to make the resultant force zero when the surface unmanned vehicle reaches the mission target point.

[0030] Preferably, the steps of constructing the velocity repulsive potential field are:

[0031] According to the velocity vectors corresponding to the unmanned boat and the dynamic obstacle, a velocity vector difference between the unmanned boat and the dynamic obstacle is obtained;

[0032] According to the velocity vector difference, the angle between the vector direction corresponding to the velocity vector difference and the line connecting the unmanned boat to the dynamic obstacle, a velocity repulsive potential field is constructed.

[0033] Preferably, the expression of the velocity repulsive potential field is:

[0034]

[0035] In the formula, represents the velocity repulsive potential field; Represents the velocity vector difference between the unmanned boat and the dynamic obstacle; represents the velocity repulsion coefficient; Represents the angle between the velocity vector difference direction and the line between the unmanned boat and the dynamic obstacle; Indicates the distance between the unmanned boat and the dynamic obstacle; Represents the radius of action of the velocity repulsion field.

[0036] Preferably, the expression of velocity repulsion is:

[0037]

[0038] In the formula, represents velocity repulsion; Indicates the geodetic coordinate system Axis and velocity vector difference The angle formed; express Unit vector of direction; express Unit vector of direction; Indicates that the unmanned boat and the dynamic obstacle are Distance of direction; Indicates that the unmanned boat and the dynamic obstacle are Distance of direction; Indicates the distance between the unmanned boat and the dynamic obstacle; represents the radius of action of the velocity repulsion field; Represents the angle between the velocity vector difference direction and the line between the unmanned boat and the dynamic obstacle; Represents the gradient operator.

[0039] The beneficial effects of the present invention are:

[0040] The present invention introduces a virtual environment repulsive potential field and a velocity repulsive field on the basis of the gravitational potential field and the repulsive potential field of the artificial potential field, that is, a virtual environment repulsive potential field is introduced for the static obstacle environment, which can effectively avoid obstacles in the path planning process of the surface unmanned boat while avoiding the target being unreachable due to the local minimum problem. The velocity repulsive field is introduced for the dynamic obstacle environment, which enables the unmanned boat to analyze the speed relationship between the unmanned boat and the obstacle. That is, the present invention introduces a virtual environment repulsive potential field for static obstacles and a velocity repulsive potential field for dynamic obstacles, so that the unmanned boat can effectively avoid obstacles on the basis of the traditional artificial potential field method, and then obtain the optimal planning path. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a flow chart of an intelligent path planning method for a marine unmanned system based on an obstacle avoidance improved repulsive potential field of the present invention;

[0043] Figure 2 This is the path planning result diagram after introducing the virtual environment repulsive potential field on the basis of the artificial potential field;

[0044] Figure 3 This is a diagram showing the magnitude and direction of the gravitational force on the unmanned boat when path planning is performed after the virtual environment repulsive potential field is introduced on the basis of the artificial potential field;

[0045] Figure 4 This is a diagram showing the magnitude and direction of the repulsive force on the unmanned boat when path planning is performed after the virtual environment repulsive potential field is introduced on the basis of the artificial potential field.

[0046] Figure 5 This is a diagram showing the magnitude and direction of the virtual environment repulsion force on the unmanned boat when path planning is performed after the virtual environment repulsion force field is introduced on the basis of the artificial potential field;

[0047] Figure 6 This is a diagram showing the magnitude and direction of the resultant force on the unmanned boat when path planning is performed after the virtual environment repulsive potential field is introduced on the basis of the artificial potential field;

[0048] Figure 7The result diagram of the post-path planning under the target artificial potential field at simulation time t=15;

[0049] Figure 8 The result diagram of the post-path planning under the target artificial potential field at simulation time t=25;

[0050] Fig. 9 The result diagram of the post-path planning under the target artificial potential field at simulation time t=35;

[0051] Fig.10 This is the result diagram of the path planning under the target artificial potential field at simulation time t=150. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] An embodiment of an intelligent path planning method for a marine unmanned system based on an obstacle avoidance improved repulsive potential field of the present invention is as follows: Figure 1 As shown, including:

[0054] S1. Establishing an artificial potential field for the working environment of the surface unmanned vehicle;

[0055] Specifically, the artificial potential field includes: gravitational potential field and repulsive potential field.

[0056] For example, in a specific embodiment, the gravitational potential field is generated by the mission target point, providing a gravitational force for the movement of the unmanned boat, and the unmanned boat is continuously driven towards the mission target point under the action of the gravitational potential field. The magnitude of the gravitational force generated by the gravitational potential field is usually related to the distance between the unmanned boat and the target. The farther the distance, the greater the gravitational force. When the gravitational force drops to 0, the unmanned boat coincides with the target point, so the expression of the gravitational potential field of this embodiment is:

[0057]

[0058] In the formula, Indicates the position of the unmanned surface vehicle The gravitational potential field at time ; represents the proportional gain parameter of the gravitational potential field; Indicates the location of the mission target point that the surface unmanned vehicle needs to reach; Indicates the position of the unmanned surface vehicle Go to the mission target location The square of the distance between .

[0059] Among them, the negative gradient of the gravitational potential field function can be obtained to obtain the gravitational force received by the unmanned boat in the gravitational potential field, that is, the expression of the gravitational force received by the unmanned boat in the gravitational potential field is:

[0060]

[0061] In the formula, represents the gravitational force on the unmanned boat in the gravitational potential field; Represents the gradient operator, which is a vector differential operator used to describe the rate and direction of change of a scalar field in space.

[0062] For example, in a specific embodiment, in order to avoid collision between the unmanned boat and obstacles, the artificial potential field method introduces a repulsive potential field. Each obstacle generates a repulsive potential field around it, so that the unmanned boat is repelled and tends to stay away from the obstacle. The strength of the repulsive potential field is usually inversely proportional to the distance between the unmanned boat and the obstacle, which ensures that the unmanned boat can effectively avoid obstacles. At the same time, the repulsive potential field has an effective radius , can be adjusted appropriately according to the needs, and it is defined that repulsion will only be felt within the action radius of the repulsive potential field, that is, the expression of the repulsive potential field is:

[0063]

[0064] In the formula, Indicates the position of the unmanned surface vehicle The repulsive potential field at time represents the repulsion coefficient; Indicates the location of static obstacles; Indicates the distance between the surface unmanned vehicle and the static obstacle; Indicates the action radius of the preset repulsive potential field; Indicates the obstacle effect radius.

[0065] Among them, by calculating the negative gradient of the repulsive potential field, it can be obtained that the repulsive force exerted on the unmanned boat in the repulsive potential field is:

[0066]

[0067] In the formula, It means that the unmanned boat is subject to repulsive force in the repulsive potential field; Represents the gradient operator.

[0068] S2, constructing a virtual environment repulsive potential field coordinate system;

[0069] Specifically, the unmanned boat is taken as the origin of the coordinate system, and the direction of the unmanned boat pointing to the mission target point is Axis direction, the direction perpendicular to the unmanned boat pointing to the mission target point is Axis direction, construct the virtual environment repulsive potential field coordinate system.

[0070] For example, in a specific embodiment, in order to avoid the unreachable mission target point and the local minimum when the traditional artificial potential field method is used for path planning, it is necessary to introduce a new repulsive potential field based on the artificial potential field method, and record the repulsive potential field as the virtual environment repulsive potential field. The virtual environment repulsive potential field coordinate system takes the unmanned boat as the origin, and the unmanned boat is the origin of the coordinate system. The direction of the unmanned boat pointing to the mission target point is Axis direction, the direction perpendicular to the unmanned boat pointing to the mission target point is Axis direction.

[0071] S3, establishing a virtual environment repulsive potential field;

[0072] Specifically, the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are obtained; according to the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system, a virtual environment repulsive potential field is established along the tangent direction of the obstacle edge in the working environment of the surface unmanned boat.

[0073] Exemplarily, in a specific embodiment, the step of obtaining the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system is: performing coordinate conversion between the virtual environment repulsive potential field coordinate system and the earth coordinate system, and obtaining the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system.

[0074] Among them, the surface unmanned boat is located in the geodetic coordinate system The coordinates below are , the coordinates of the target point are , the line connecting the unmanned boat and the target point and The angle between the axes is , translate and rotate the geodetic coordinate system, and move the origin of the geodetic coordinate system to The virtual environment repulsive potential field coordinate system is established with the unmanned boat as the origin. , then the point of the static obstacle in the geodetic coordinate system is The coordinates in the virtual environment repulsive potential field coordinate system are:

[0075]

[0076] In the formula, Indicates the position coordinates of the static obstacle in the geodetic coordinate system; Represents the static position coordinates after the translation transformation of the geodetic coordinate system; Represents the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the position coordinates of the origin of the virtual environment repulsive potential field coordinate system in the earth coordinate system; The line connecting the unmanned boat to the mission target point and the geodetic coordinate system The angle of the axis.

[0077] For example, in a specific embodiment, according to the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system, a virtual environment repulsive potential field is established along the tangent direction of the obstacle edge in the working environment of the surface unmanned boat, and the virtual environment repulsive potential field is:

[0078]

[0079] In the formula, Represents the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system; is a unit vector along the y-axis.

[0080] First, consider that the static obstacle is located on the right side of the virtual environment repulsive potential field coordinate system, that is, When the vertical coordinate of the static obstacle is 0, the gravitational force may lead to a local minimum. At this time, the repulsive force needs to guide the unmanned boat toward the upper or lower half of the y-axis, that is, ;when In order to avoid the gravitational force and repulsive force pointing in different directions, which will lead to path oscillation, the gravitational force provided by the obstacle should be directed towards the mission target point. In summary, we get The virtual environment repulsive potential field at this time is:

[0081]

[0082] In the formula, represents the repulsive potential field of the virtual environment; Represents the horizontal coordinate of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the ordinate of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the virtual environment repulsion coefficient.

[0083] When the static obstacle is on the left side of the surface unmanned boat, At this time, the static obstacle will not affect the surface unmanned boat to reach the mission target point, but it will still generate a repulsive force. In order to make this repulsive force prompt the surface unmanned boat to run to the mission target point, The virtual environment repulsive potential field at this time is:

[0084]

[0085] In the formula, Represents the virtual environment repulsive potential field coordinate system The angle between the positive direction of the axis and the vector pointing from the mission target point to the obstacle.

[0086] At this point, the repulsive potential field of the virtual environment can be obtained as:

[0087]

[0088] Among them, the virtual environment repulsion is:

[0089]

[0090] In the formula, Represents virtual environment repulsion; represents the repulsive potential field of the virtual environment; represents the virtual environment repulsion coefficient; Indicates the distance between the unmanned boat and the static obstacle; Represents the radius of action of the repulsive potential field of the virtual environment; represents the gradient operator; Represents the repulsive potential field along the virtual environment The unit vector of the direction; is the distance between the unmanned boat and the mission target point, is a preset conditional parameter, which is used to make the resultant force zero when the horizontal plane unmanned boat reaches the mission target point, so that the unmanned boat path planning will not have local optimal and target unreachable problems).

[0091] S4, establish velocity repulsive potential field;

[0092] Specifically, according to the velocity vectors corresponding to the unmanned boat and the dynamic obstacle, a velocity repulsion potential field is established in the working environment of the surface unmanned boat.

[0093] For example, in a specific embodiment, when facing dynamic obstacles during the path planning of a surface unmanned boat, the obstacle avoidance ability of the traditional artificial potential field method is weak. Therefore, this embodiment considers the speed characteristics of dynamic obstacles, analyzes the speed relationship between the unmanned boat and the dynamic obstacles, and constructs a speed repulsion potential field to guide the unmanned boat to effectively avoid obstacles and reach the mission target point during the path planning process. The steps of constructing the speed repulsion potential field are: according to the speed vectors corresponding to the unmanned boat and the dynamic obstacle, obtain the speed vector difference between the unmanned boat and the dynamic obstacle; according to the speed vector difference, the angle between the vector direction corresponding to the speed vector difference and the line connecting the unmanned boat to the dynamic obstacle, construct a speed repulsion potential field.

[0094] Among them, the expression of velocity repulsion potential field is:

[0095]

[0096] In the formula, represents the velocity repulsive potential field; Represents the velocity vector difference between the unmanned boat and the dynamic obstacle; represents the velocity repulsion coefficient; The angle between the vector direction of the velocity vector difference and the line between the unmanned boat and the dynamic obstacle; Indicates the distance between the unmanned boat and the dynamic obstacle; Represents the radius of action of the velocity repulsion field.

[0097] Among them, when the direction of the unmanned boat is opposite to the direction of movement of the obstacle, the unmanned boat will not collide with the dynamic obstacle during the path planning process of the unmanned boat, so in this case, there is no need to consider the speed information of the dynamic obstacle. Further consideration shows that when the angle of the speed vector difference between the unmanned boat and the dynamic obstacle is When the velocity repulsion potential field is within this range, the dynamic obstacles will have a certain impact on the path planning of the unmanned boat. At this time, the velocity information of the dynamic obstacles needs to be considered. Therefore, by calculating the negative gradient of the velocity repulsion potential field, the velocity repulsion can be obtained as:

[0098]

[0099] In the formula, represents velocity repulsion; Indicates the geodetic coordinate system Axis and velocity vector difference The angle formed; express Unit vector of direction; express Unit vector of direction; Indicates that the unmanned boat and the dynamic obstacle are Distance of direction; Indicates that the unmanned boat and the dynamic obstacle are Distance of direction; Indicates the distance between the unmanned boat and the dynamic obstacle; Indicates the radius of action of the velocity repulsion field (i.e., the radius of action when a dynamic obstacle appears on the unmanned boat). A velocity repulsive potential field will be introduced within the range); The angle between the vector direction of the velocity vector difference and the line between the unmanned boat and the dynamic obstacle; Represents the gradient operator.

[0100] S5. Plan the path for the unmanned surface boat;

[0101] The virtual environment repulsive potential field and the velocity repulsive potential field are introduced into the artificial potential field to obtain the target artificial potential field, and the artificial potential field method is used to plan the path of the surface unmanned vehicle under the target artificial potential field to obtain the path trajectory of the surface unmanned vehicle.

[0102] The present embodiment is described below in conjunction with specific simulation data:

[0103] On the basis of steps S1-S3, the path of the surface unmanned boat is planned, that is, the path of the surface unmanned boat is planned under the artificial potential field and the repulsive potential field of the virtual environment. First, the starting point, target point, static obstacle position and force field parameters are set for the static environment in step S3. The starting position of the unmanned boat is the origin of the coordinate system (0, 0), the target point position is (50, 50), seven static obstacles are set, and five circular obstacles are distributed, and their center positions and radii are (20, 15, 3), (5, 25, 4), (30, 40, 4), (25, 40, 3) (15, 45, 3), and there are two quadrilateral obstacles. The vertex coordinates of the first quadrilateral obstacle are [(19, 23); (25, 22); (26, 28); (19, 28)], and the vertex coordinates of the second quadrilateral obstacle are [(35, 28); (45, 28); (45, 33); (35, 33)], and the potential field parameters corresponding to the artificial potential field and the virtual environment repulsive potential field are set as follows: gravitational coefficient =1, repulsion coefficient =19, virtual environment repulsion coefficient The path planning simulation results under the potential field parameters are as follows: Figures 2 to 5 As shown in Figure 2. Among them, the path planning result after introducing the virtual environment repulsive potential field only on the basis of the artificial potential field is shown in Figure 2. Figure 2 As shown, from Figure 2 It can be seen that under the action of the virtual environment repulsive potential field, the unmanned boat can avoid static obstacles more smoothly in the process of reaching the mission target point. After introducing the virtual environment repulsive potential field on the basis of the artificial potential field, the magnitude and direction of the gravitational force on the unmanned boat during path planning are shown in the following figure. Figure 3 As shown in the figure, after introducing the virtual environment repulsive potential field on the basis of the artificial potential field and performing path planning, the magnitude and direction of the repulsive force on the unmanned boat are as follows Figure 4 As shown in the figure, after introducing the virtual environment repulsive force field on the basis of the artificial potential field and performing path planning, the magnitude and direction of the virtual environment repulsive force on the unmanned boat are as follows Figure 5 As shown in the figure, after introducing the virtual environment repulsive potential field on the basis of the artificial potential field and performing path planning, the magnitude and direction of the resultant force on the unmanned boat are as follows Figure 6 As shown, from Figure 3 and Figure 4 It can be seen that when the unmanned boat is greatly affected by the original repulsive force, Figure 5 It can be seen that the virtual environment repulsion provides a repulsive force along the edge of the obstacle to the unmanned boat, and finally combined with Figure 6It can be seen from the magnitude and direction of the resultant force exerted on the unmanned boat during path planning after the introduction of the virtual environment repulsive potential field that the introduction of the virtual environment repulsive potential field enables the unmanned boat to avoid obstacles more smoothly and in a shorter distance.

[0104] On the basis of steps S1-S5, the path of the surface unmanned boat is planned, that is, in this step S4, the starting point, mission target point, static obstacle position, dynamic obstacle starting point position and potential field parameters of the surface unmanned boat are set for the static environment. The starting position of the unmanned boat is the origin of the coordinate system (0, 0), the target point position is (45, 45), a dynamic obstacle and four static obstacles are set, there are two circular obstacles, the center position and radius of which are (15, 35, 3) and (35, 15, 4) respectively, and there are two quadrilateral obstacles. The vertex coordinate positions of the first quadrilateral obstacle are [(10, 15); (20, 18); (24, 28); (18, 23)], and the vertex coordinate positions of the second quadrilateral obstacle are [(35, 28); (40, 28); (40, 38); (35, 38)], the starting point coordinates of the dynamic obstacle are (18, 5), and the potential field parameters are set as the gravity coefficient =1, repulsion coefficient =20, velocity repulsion coefficient The path planning simulation results under this parameter setting are as follows: Figures 7 to 10 shown. Figure 7 The result of post-path planning under the target artificial potential field at simulation time t=15; Figure 8 The result of post-path planning under the target artificial potential field at simulation time t=25; Fig. 9 The result of post-path planning under the target artificial potential field at simulation time t=35; Fig.10 is the result of post-path planning under the target artificial potential field at simulation time t=150; Figures 7 to 10 It can be seen from the repulsive lines of the medium-speed repulsive potential field that under the action of this speed repulsive potential field, when the unmanned boat encounters a dynamic obstacle, by analyzing the speed information of itself and the obstacle, a force is given to the unmanned boat to guide the unmanned boat to bypass the dynamic obstacle, thereby achieving the effect of dynamic obstacle avoidance in the path planning process of the unmanned boat, and after avoiding the dynamic obstacle, it can continue to plan the path in the static environment and finally reach the mission target point.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An intelligent path planning method for marine unmanned systems based on obstacle avoidance improved repulsive potential field, characterized in that: include: Establishing an artificial potential field for the working environment of the surface unmanned boat, wherein the artificial potential field includes: a gravitational potential field and a repulsive potential field; The unmanned boat is taken as the origin of the coordinate system, and the direction of the unmanned boat pointing to the mission target point is Axis direction, the direction perpendicular to the unmanned boat pointing to the mission target point is Axis direction, construct the virtual environment repulsive potential field coordinate system; the expression of the virtual environment repulsive potential field is: In the formula, represents the repulsive potential field of the virtual environment; Represents the horizontal coordinate of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the ordinate of the static obstacle in the virtual environment repulsive potential field coordinate system; represents the virtual environment repulsion coefficient; Represents the virtual environment repulsive potential field coordinate system The angle between the positive direction of the axis and the vector pointing from the mission target point to the obstacle; The position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are obtained; according to the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system, a virtual environment repulsive potential field is established along the tangent direction of the obstacle edge in the working environment of the surface unmanned boat; the steps of constructing the velocity repulsive potential field are: according to the velocity vectors corresponding to the unmanned boat and the dynamic obstacle, the velocity vector difference between the unmanned boat and the dynamic obstacle is obtained; according to the velocity vector difference, the vector direction corresponding to the velocity vector difference and the angle between the line connecting the unmanned boat and the dynamic obstacle, the velocity repulsive potential field is constructed; wherein, the expression of the velocity repulsive potential field is: In the formula, represents the velocity repulsive potential field; Represents the velocity vector difference between the unmanned boat and the dynamic obstacle; represents the velocity repulsion coefficient; Represents the angle between the velocity vector difference direction and the line between the unmanned boat and the dynamic obstacle; Indicates the distance between the unmanned boat and the dynamic obstacle; represents the radius of action of the velocity repulsion field; According to the velocity vectors corresponding to the unmanned boat and the dynamic obstacle, a velocity repulsion potential field is established in the working environment of the surface unmanned boat; The virtual environment repulsive potential field and the velocity repulsive potential field are introduced into the artificial potential field to obtain the target artificial potential field, and the artificial potential field method is used to plan the path of the surface unmanned vehicle under the target artificial potential field to obtain the path trajectory of the surface unmanned vehicle.

2. According to claim 1, a method for intelligent path planning of a marine unmanned system based on obstacle avoidance improved repulsive potential field is characterized in that: The expression of gravitational potential field is: In the formula, Indicates the position of the unmanned surface vehicle The gravitational potential field at time ; represents the proportional gain parameter of the gravitational potential field; Indicates the location of the mission target point that the surface unmanned vehicle needs to reach; Indicates the position of the unmanned surface vehicle Go to the mission target location The square of the distance between .

3. The intelligent path planning method for marine unmanned system based on obstacle avoidance improved repulsive potential field according to claim 1 is characterized in that: The expression of the repulsive potential field is: In the formula, Indicates the position of the unmanned surface vehicle The repulsive potential field at time represents the repulsion coefficient; Indicates the location of static obstacles; Indicates the distance between the surface unmanned vehicle and the static obstacle; Indicates the action radius of the preset repulsive potential field; Indicates the obstacle effect radius.

4. The method for intelligent path planning of a marine unmanned system based on obstacle avoidance and improved repulsive potential field according to claim 1, characterized in that: The steps to obtain the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are: The virtual environment repulsive potential field coordinate system and the earth coordinate system are transformed, and the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are obtained.

5. The method for intelligent path planning of a marine unmanned system based on obstacle avoidance and improved repulsive potential field according to claim 4, characterized in that: The position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system are: In the formula, Indicates the position coordinates of the static obstacle in the geodetic coordinate system; Represents the static position coordinates after the translation transformation of the geodetic coordinate system; Represents the position coordinates of the static obstacle in the virtual environment repulsive potential field coordinate system; Represents the position coordinates of the origin of the virtual environment repulsive potential field coordinate system in the earth coordinate system; The line connecting the unmanned boat to the mission target point and the geodetic coordinate system The angle of the axis.

6. The method for intelligent path planning of a marine unmanned system based on obstacle avoidance and improved repulsive potential field according to claim 1, characterized in that: The expression of virtual environment repulsion is: In the formula, Represents virtual environment repulsion; represents the repulsive potential field of the virtual environment; represents the virtual environment repulsion coefficient; Indicates the distance between the unmanned boat and the static obstacle; Represents the radius of action of the repulsive potential field of the virtual environment; represents the gradient operator; Represents the repulsive potential field along the virtual environment The unit vector of the direction; is the distance between the unmanned boat and the mission target point, It is a preset condition parameter, which is used to make the resultant force zero when the surface unmanned vehicle reaches the mission target point.

7. The method for intelligent path planning of a marine unmanned system based on obstacle avoidance and improved repulsive potential field according to claim 1, characterized in that: The expression of velocity repulsion is: In the formula, represents velocity repulsion; Indicates the geodetic coordinate system Axis and velocity vector difference The angle formed; express Unit vector of direction; express Unit vector of direction; Indicates that the unmanned boat and the dynamic obstacle are Distance of direction; Indicates that the unmanned boat and the dynamic obstacle are Distance of direction; Indicates the distance between the unmanned boat and the dynamic obstacle; represents the radius of action of the velocity repulsion field; Represents the angle between the velocity vector difference direction and the line between the unmanned boat and the dynamic obstacle; Represents the gradient operator.

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