Autonomous underwater robot navigation path planning method, device and system

Abstract

The present invention relates to the field of robot path planning technology, and specifically to a method, device and system for autonomous underwater robot navigation path planning. The present invention obtains the global path of the autonomous underwater robot from the starting point to the target point; based on the global path, analyzes the change of the robot's path and heading, and divides the global path into multiple stage paths; when the autonomous underwater robot is navigating, analyzes the obstacle risk of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot, respectively, and obtains the risk warning degree of the autonomous underwater robot at the current moment; according to the risk warning degree, combined with the stage path, the local path of the autonomous underwater robot at the current moment is adjusted. This method can avoid the risk of dynamic obstacles on the basis of ensuring that there is no deviation in the general direction of navigation, and realize efficient and accurate path planning.

Description

Technical Field

[0001] The present invention relates to the technical field of robot path planning, and in particular to a method, device and system for autonomous underwater robot navigation path planning. Background Art

[0002] Autonomous Underwater Vehicle (AUV) is a robot that can independently perform tasks in underwater environments. It is widely used in marine scientific research, military reconnaissance, environmental monitoring, resource detection, seabed exploration and other fields. Among them, navigation path planning is one of the most critical technologies for autonomous underwater robots when performing tasks. It involves how to efficiently and reliably plan the robot's motion trajectory so that it can avoid obstacles, avoid energy waste, and improve the success rate of the task.

[0003] At present, when planning the route of an autonomous underwater robot, path planning is generally carried out through global planning or local planning. The global path planning algorithm usually relies on a static map to provide an optimal path from the starting point to the target point, but this ignores the changes in the dynamic environment and immediate obstacles; while the local path planning algorithm focuses on real-time obstacle avoidance and path adjustment, but it is usually based on local information and may not provide a globally optimal solution. At present, it is difficult to make a trade-off between the local and global aspects when planning a path, which makes it difficult to achieve the optimal solution for path planning and difficult to obtain a path planning method efficiently. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a method, device and system for autonomous underwater robot navigation path planning.

[0005] According to a first aspect of an embodiment of the present invention, a method for planning a navigation path of an autonomous underwater robot is provided, and the technical solution adopted is specifically as follows:

[0006] Obtain the global path of the autonomous underwater robot from the starting point to the target point;

[0007] Based on the global path, analyzing the path and heading changes of the robot, and dividing the global path into a plurality of phased paths;

[0008] When the autonomous underwater robot is navigating, the obstacle risk degree of the surrounding environment, the relative stability of the water flow and the position change of the robot are analyzed respectively to obtain the risk warning degree of the autonomous underwater robot at the current moment;

[0009] According to the risk warning degree and in combination with the phased path, the local path of the autonomous underwater robot at the current moment is adjusted.

[0010] In some embodiments of the present invention, based on the global path, the path and heading changes of the robot are analyzed, and the global path is divided into a plurality of stage paths to obtain the stage paths, including:

[0011] Obtaining path points of the global path;

[0012] Analyze the azimuth deflection of the path points to obtain key points of the global path;

[0013] According to the key points, the global path is divided into a plurality of stage paths to obtain stage paths.

[0014] In some embodiments of the present invention, analyzing the azimuth deflection of the path point to obtain the key point of the global path includes:

[0015] Obtaining coordinate information of the path point and its neighboring path points;

[0016] Based on the coordinate information, analyzing the standard deviation of the displacement difference between the path point and its neighboring path points in a coordinate direction to obtain the azimuth deflection degree of the path point;

[0017] According to the azimuth deflection of all the path points, an azimuth deflection curve is drawn, and all maximum value points of the azimuth deflection curve are obtained as key points of the global path.

[0018] In some embodiments of the present invention, when the autonomous underwater robot is navigating, analyzing the obstacle risk of the surrounding environment at the current moment includes:

[0019] When the autonomous underwater robot is navigating, it uses sonar detectors to obtain feedback on obstacles in the surrounding environment at the current moment and mark the direction of the obstacles;

[0020] The obstacle risk of the surrounding environment is obtained by analyzing the ratio of the number of marked directions to the total number of all detected directions.

[0021] In some embodiments of the present invention, when the autonomous underwater robot is navigating, analyzing the relative stability of the water flow at the current moment includes:

[0022] When the autonomous underwater robot is navigating, the water flow velocity at the current moment and the water flow velocity at the previous moment are obtained through the flow velocity sensor;

[0023] The standard deviation of the flow velocity difference between the current water velocity and the previous water velocity is analyzed to obtain the relative stability of the water flow at the current moment.

[0024] In some embodiments of the present invention, when the autonomous underwater robot is navigating, analyzing the position change of the robot at the current moment includes:

[0025] When the autonomous underwater robot is navigating, obtain the position coordinates of the robot at the current moment and the previous moment;

[0026] The Euclidean distance between the current position coordinates and the previous position coordinates is analyzed to obtain the position change of the robot at the current moment.

[0027] In some embodiments of the present invention, adjusting the local path of the autonomous underwater robot at the current moment according to the risk warning degree and in combination with the phased path includes:

[0028] Set risk warning thresholds;

[0029] Determining whether the risk warning degree is greater than or equal to the risk warning threshold;

[0030] If yes, taking the current position of the autonomous underwater robot as the local starting point, taking the end point of the staged path where the current position of the autonomous underwater robot is located as the local target point, and using a local path planning algorithm to adjust the local path of the autonomous underwater robot from the local starting point to the local target point;

[0031] If not, the autonomous underwater vehicle continues to navigate according to the global path at the current moment.

[0032] In some embodiments of the present invention, obtaining a global path of an autonomous underwater robot from a starting point to a target point includes:

[0033] Based on the underwater static map, the global path of the autonomous underwater robot from the starting point to the target point is obtained through the global path planning algorithm.

[0034] According to a second aspect of an embodiment of the present invention, a navigation path planning device for an autonomous underwater robot is provided, comprising: a memory and a processor, wherein:

[0035] The memory is used to store program code;

[0036] The processor is used to read the program code stored in the memory and execute the method described in the first aspect of the embodiment of the present invention.

[0037] According to a third aspect of an embodiment of the present invention, a navigation path planning system for an autonomous underwater robot is provided, comprising:

[0038] A global path acquisition module is used to obtain the global path of the autonomous underwater robot from the starting point to the target point;

[0039] A phased path division module, used for analyzing the path and heading changes of the robot based on the global path, and dividing the global path into a plurality of phased paths;

[0040] The risk warning degree analysis module is used to analyze the obstacle risk degree of the surrounding environment, the relative stability of the water flow and the position change of the robot at the current moment when the autonomous underwater robot is navigating, and obtain the risk warning degree of the autonomous underwater robot at the current moment;

[0041] The local path adjustment module is used to adjust the local path of the autonomous underwater robot at the current moment according to the risk warning degree and in combination with the phased path.

[0042] Compared with the prior art, the autonomous underwater robot navigation path planning method, device and system provided by the present invention have the following beneficial effects:

[0043] The present invention obtains the global path of the autonomous underwater robot from the starting point to the target point; based on the global path, analyzes the change of the robot's path and heading, and divides the global path into multiple stage paths; when the autonomous underwater robot is navigating, analyzes the obstacle risk of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot, respectively, to obtain the risk warning degree of the autonomous underwater robot at the current moment; according to the risk warning degree, combined with the stage path, the local path of the autonomous underwater robot at the current moment is adjusted. The present invention considers the real-time operation of the autonomous underwater robot in each stage path to weigh and decide whether to adjust the planning of the local path, so as to avoid the dynamic risk factors that may appear during actual operation. The method combines the real-time operation status of the autonomous underwater robot on the basis of the global path to weigh the path planning, and can avoid the risk of dynamic obstacles on the basis of ensuring that there is no deviation in the general direction of navigation, and finally realizes efficient and accurate path planning. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are 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.

[0045] Figure 1 A schematic diagram of the basic flow of a method for planning a navigation path for an autonomous underwater robot provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the autonomous underwater robot navigation path planning method, device and system proposed by the present invention, its specific implementation method, structure, features and effects in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. Terms such as "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such article or device. In the absence of further restrictions, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the article or device including the element.

[0048] The specific scheme of the autonomous underwater robot navigation path planning method provided by the present invention is described in detail below with reference to the accompanying drawings.

[0049] See also Figure 1 , which shows the basic process of a navigation path planning method for an autonomous underwater robot provided by an embodiment of the present invention.

[0050] like Figure 1 As shown, a method for planning a navigation path for an autonomous underwater robot provided by an embodiment of the present invention specifically includes:

[0051] S100: Obtain a global path of the autonomous underwater robot from a starting point to a target point.

[0052] The navigation path of an autonomous underwater robot is not only related to its starting and ending positions and the mission points along the way, but also needs to consider factors such as underwater obstacles and environmental interference during the driving process. Therefore, before the autonomous underwater robot sails, it first obtains the heading route of the autonomous underwater robot based on the underwater static map through a global path planning algorithm, so as to present a global path from the starting point to the target point.

[0053] S200: Based on the global path, analyzing the path and heading changes of the robot, and dividing the global path into multiple phased paths.

[0054] In the global path determined based on the static map, different positions have different degrees of importance. This means that due to the influence of obstacles of fixed structures in actual static conditions, the autonomous underwater robot needs to avoid collision risks while taking into account normal activity tasks (i.e., it needs to pass through the corresponding task points during navigation). Usually in the global path, the obvious change in the path orientation indicates that there may be obstacles (such as rocks, shipwrecks or other terrain protrusions) near the path point, and when approaching these obstacles, it usually means that the autonomous underwater robot may encounter restrictions or need to detour in this area. Such path points need special attention, mainly because they may be the "critical points" for the interaction between the autonomous underwater robot and the environment, which may affect the safety and stability during navigation. Therefore, each path point in the global path is analyzed here to determine the key points of the global path, and then the global path can be divided into several phased paths for subsequent analysis.

[0055] Based on the above analysis, this embodiment analyzes the path and heading changes of the robot based on the global path and divides the global path into multiple phased paths. Further, it includes:

[0056] First, obtain the path points of the global path. Specifically, obtain the path points of the global path on the middle road line of the global path. The distance between two adjacent path points can be set to 0.1 meters or 3 meters. The specific interval distance can be determined according to the volume of the autonomous underwater robot, the complexity of the underwater environment (the degree of bending of the global path), the length of the total distance, etc. When the volume of the autonomous underwater robot is small, the underwater environment is more complex, and the length of the total distance is short, a smaller interval distance can be set, such as 0.5 meters or even 0.1 meters.

[0057] Then, the orientation deflection of the path points is analyzed to obtain the key points of the global path. Specifically:

[0058] Obtain the coordinate information of the path point and its neighboring path points, that is, obtain the coordinate information of all path points in the global path of the autonomous underwater robot, and obtain a total of M (including itself) neighboring path points and their coordinate information before and after all path points along the navigation direction of the path in the global path.

[0059] If the global path is extended in a certain direction, the path point will also maintain a continuous extension in a certain direction of the three-dimensional coordinate direction, which corresponds to the stable and unchanged position of the global path at the current stage. Conversely, when the global path deflects significantly in a certain direction, the path point will also deflect in a certain direction of the three-dimensional coordinate direction, which corresponds to the position of the deflection in the current stage of the global path. When a path point is within the path range where a significant azimuth deflection occurs, the coordinate offset of the path points in its neighborhood will be more obvious. Therefore, in this embodiment, based on the coordinate information, the standard deviation of the displacement difference between the path point and its neighboring path points in a coordinate direction is analyzed to obtain the azimuth deflection of the path point. The calculation formula for constructing the azimuth deflection of the path point is:

[0060]

[0061] in, Indicates The azimuth deviation of each path point; Represents the number of coordinate directions of the three-dimensional coordinates (i.e. 3); Indicates The path point and its neighboring path point and its adjacent path point in The absolute value of the displacement difference in the coordinate direction; Indicates The total number of waypoints and their neighboring waypoints; Indicates Find the standard deviation of all displacement differences between a path point and its neighboring path points; represents the linear normalization function.

[0062] The standard deviation of the displacement difference between adjacent path points in a single coordinate direction reflects the azimuth deviation in a single coordinate direction. The smaller the standard deviation of the displacement difference, the more balanced the coordinate direction is, that is, there is no deflection in the coordinate direction or the deflection in the coordinate direction is small. Traverse the three coordinate directions of the three-dimensional coordinates, sum the standard deviations of the displacement differences, and obtain the azimuth deflection degree of the path point.

[0063] In this way, the azimuth deviation of each path point can be obtained, and the azimuth deflection curve can be drawn according to the azimuth deflection of all path points. All maximum points of the azimuth deflection curve can be obtained as the key points of the global path, that is, the path points that have obvious azimuth deviations and need to be paid special attention to.

[0064] Finally, according to the key points, the global path is divided into multiple phased paths to obtain the phased paths. Specifically, for the global path, starting from the starting point, passing through each key point until the final target point, the global paths between adjacent key points are respectively used as each phased path to obtain the phased path, which is convenient for subsequent analysis.

[0065] S300: When the autonomous underwater robot is navigating, the obstacle risk degree of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot are analyzed respectively to obtain the risk warning degree of the autonomous underwater robot at the current moment.

[0066] The global path of the autonomous underwater robot determined by the underwater static map is processed before the autonomous underwater robot sails. It mainly relies on the environmental information collected in advance, usually including obstacles such as seabed terrain, rocks, sunken ships and other fixed structures, which are also the main targets to avoid during global path planning. However, during the navigation of the autonomous underwater robot, changes in water flow speed and direction (especially in the deep sea), floating garbage or plants in the water (moving with time and environment, unstable), and the influence of fish and other marine life, this dynamic and uncertain interference will affect the navigation of the autonomous underwater robot. Therefore, it is necessary to conduct local analysis to determine whether to adjust the local path planning.

[0067] Based on the above analysis, this embodiment obtains the risk warning degree of the autonomous underwater robot at the current moment by analyzing the obstacle risk degree of the surrounding environment, the relative stability of the water flow and the position change of the robot when the autonomous underwater robot is navigating.

[0068] When the autonomous underwater robot is navigating, the obstacle risk of the surrounding environment at the current moment is analyzed, which further includes: when the autonomous underwater robot is navigating, the feedback of the obstacles in the surrounding environment at the current moment is obtained through the sonar detector, and the direction of the obstacle is marked; the ratio of the number of marked directions to the total number of all detected directions is analyzed to obtain the obstacle risk of the surrounding environment. Specifically, a sonar detector is set on the autonomous underwater robot, and the preset safety distance is 5m. When the distance to the obstacle detected by the sonar detector in a certain direction of the autonomous underwater robot is less than or equal to the safety distance, the direction is marked, and each direction is traversed to mark all directions where the distance between the autonomous underwater robot and the obstacle is less than or equal to the safety distance, so as to obtain the number of all marked directions at the current moment, which is recorded as Then, the obstacle risk of the surrounding environment of the autonomous underwater robot at the current moment can be analyzed. The larger the ratio of the marked direction to the total detected direction, the higher the obstacle risk of the surrounding environment of the autonomous underwater robot at the current moment. Therefore, the quantitative formula for constructing the obstacle risk of the surrounding environment at the current moment is:

[0069]

[0070] in, Indicates the obstacle risk level of the surrounding environment of the autonomous underwater robot at the current moment; Indicates the total number of directions detected by the autonomous underwater robot sonar detector at the current moment; It indicates the number of marked directions, that is, the number of directions in which the distance between the autonomous underwater robot and the obstacle is less than or equal to the safety distance at the current moment.

[0071] The larger the ratio of the marked directions to the total detected directions, the greater the number of obstacles around the autonomous underwater robot at the current moment, which means that the obstacle risk of the surrounding environment of the autonomous underwater robot at the current moment is higher.

[0072] The underwater environment is complex and the flow pattern of water under different seabed terrains (such as ridges, gullies, canyons, etc.) will be affected, causing the flow rate to speed up or slow down, which will have a potential impact on the navigation of the autonomous underwater robot. Therefore, when the autonomous underwater robot is navigating, the relative stability of the water flow at the current moment is analyzed. Furthermore, the impact of the external water flow during the current navigation process can be reflected by the water flow velocity conditions that the autonomous underwater robot has been subjected to along the driving direction in the past period of time at the current moment. Specifically, first, when the autonomous underwater robot is navigating, the water flow velocity at the current moment and the water flow velocity at the previous moment are obtained through the flow velocity sensor; then the standard deviation of the flow velocity difference between the water flow velocity at the current moment and the water flow velocity at the previous moment is analyzed to obtain the relative stability of the water flow at the current moment. The quantitative formula for constructing the relative stability of the water flow at the current moment is:

[0073]

[0074] in, Indicates the relative stability of the water flow at the current moment; Indicates the current moment and its previous The absolute value of the water velocity difference at each moment; Indicates the total number of all moments before the current moment; It means to find the standard deviation of all water flow velocity differences between the current moment and all previous moments; represents the linear normalization function.

[0075] By analyzing the fluctuation of water flow velocity, that is, the relative stability of the current water flow, the potential environmental impacts that the current autonomous underwater robot may face can be reflected.

[0076] During the navigation of an autonomous underwater robot, the distance of its position change is affected by many factors such as water pressure. The greater the distance of its position change within a fixed time, it means that the environment where it is located may be relatively not fully explored in real time, so its corresponding safety risk may be greater. Therefore, when the autonomous underwater robot is navigating, the position change of the robot at the current moment is analyzed. Furthermore, the position offset change at the current moment can be compared with the previous moment. Specifically, first, when the autonomous underwater robot is navigating, the position coordinates of the robot at the current moment and the previous moment are obtained; then the Euclidean distance between the position coordinates at the current moment and the position coordinates at the previous moment is analyzed to obtain the position change of the robot at the current moment. The quantitative formula for constructing the position change of the robot at the current moment is:

[0077]

[0078] in, Indicates the position change of the autonomous underwater robot at the current moment; Indicates the position coordinates of the autonomous underwater robot at the current moment; Indicates the position coordinates of the autonomous underwater robot at the previous moment of the current moment; It represents calculating the Euclidean distance between the position coordinates of the autonomous underwater robot at the current moment and the previous moment; represents the linear normalization function.

[0079] By analyzing the Euclidean distance between the position coordinates of the autonomous underwater robot at the current moment and the previous moment, the position change of the autonomous underwater robot at the current moment is expressed. The larger the Euclidean distance, the greater the position change of the autonomous underwater robot at the current moment.

[0080] After obtaining the obstacle risk degree of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot, the risk warning degree of the autonomous underwater robot at the current moment is obtained according to the obstacle risk degree of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot. Specifically, based on the above characteristics, a comprehensive analysis is performed to determine the risks that the autonomous underwater robot may encounter. Taking the relative stability of the water flow at the current moment as the benchmark, the greater the relative stability of the water flow, the greater the external interference to the autonomous underwater robot at the current moment. In this way, more attention should be paid to the obstacle risk of the surrounding environment of the autonomous underwater robot at the current moment, so as to feel the obstacle impact at the current moment more realistically and intuitively; and when the relative stability of the water flow is smaller, it means that the autonomous underwater robot is less disturbed by the outside world (the environmental impact presented by the external water flow velocity is stable), but in the actual autonomous underwater robot's heading process, the degree of its own position change will also affect the risks it may encounter. Even if the external interference is small, when its own position changes faster, the actual environment changes too fast, which may lead to risk impacts that are difficult to capture. Therefore, in this case, more attention should be paid to the position change of the autonomous underwater robot at the current moment. Based on the above analysis, according to the obstacle risk of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot, the quantitative formula for the risk warning degree of the autonomous underwater robot at the current moment is constructed as follows:

[0081]

[0082] in, Indicates the risk warning degree of the autonomous underwater robot at the current moment; Indicates the relative stability of the water flow at the current moment; Indicates the obstacle risk level of the surrounding environment of the autonomous underwater robot at the current moment; Indicates the position change of the autonomous underwater robot at the current moment.

[0083] S400: According to the risk warning degree and in combination with the phased path, the local path of the autonomous underwater robot at the current moment is adjusted.

[0084] According to the risk warning degree and the staged path, the local path of the autonomous underwater robot at the current moment is adjusted, further including: setting a risk warning threshold, and the value of the risk warning threshold can be 0.45. If the risk warning degree is greater than or equal to the risk warning threshold, it is considered that when the autonomous underwater robot navigates according to the current global path at the current moment, an unexpected situation may occur, so the current heading should be readjusted by local path planning. The specific adjustment method is to take the current position of the autonomous underwater robot as the local starting point, and the end point of the staged path where the position of the autonomous underwater robot at the current moment is located as the local target point, and use the local path planning algorithm (such as the RRT algorithm) to adjust the local path of the autonomous underwater robot from the local starting point to the local target point, so as to ensure that the obstacle avoidance in the current local area is completed under the premise that the overall direction remains unchanged. If the risk warning degree is less than the risk warning threshold, it is considered that when the autonomous underwater robot navigates according to the current global path at the current moment, the possibility of an unexpected situation is small, so the autonomous underwater robot can continue to navigate according to the global path at the current moment.

[0085] Based on the same inventive concept as the above method, this embodiment also provides an autonomous underwater robot navigation path planning device.

[0086] Specifically, an autonomous underwater robot navigation path planning device includes a memory and a processor, wherein:

[0087] A memory for storing program codes;

[0088] The processor is used to read the program code stored in the memory and execute it to obtain the global path of the autonomous underwater robot from the starting point to the target point; based on the global path, analyze the change of the path and heading of the robot, and divide the global path into multiple stage paths; when the autonomous underwater robot is navigating, analyze the obstacle risk degree of the surrounding environment at the current moment, the relative stability of the water flow and the position change of the robot, and obtain the risk warning degree of the autonomous underwater robot at the current moment; according to the risk warning degree, combined with the stage path, adjust the local path of the autonomous underwater robot at the current moment.

[0089] Based on the same inventive concept as the above method, this embodiment also provides an autonomous underwater robot navigation path planning system.

[0090] Specifically, an autonomous underwater robot navigation path planning system includes a global path acquisition module 21, a phased path division module 22, a risk warning degree analysis module 23 and a local path adjustment module 24. Among them:

[0091] A global path acquisition module 21 is used to acquire a global path of the autonomous underwater robot from a starting point to a target point;

[0092] The phased path division module 22 is used to analyze the path and heading changes of the robot based on the global path and divide the global path into multiple phased paths;

[0093] The risk warning degree analysis module 23 is used to analyze the obstacle risk degree of the surrounding environment, the relative stability of the water flow and the position change of the robot at the current moment when the autonomous underwater robot is navigating, and obtain the risk warning degree of the autonomous underwater robot at the current moment;

[0094] The local path adjustment module 24 is used to adjust the local path of the autonomous underwater robot at the current moment according to the risk warning degree and in combination with the staged path.

[0095] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0096] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A navigation path planning method for an autonomous underwater robot, characterized in that: The method comprises: Obtain the global path of the autonomous underwater robot from the starting point to the target point; Based on the global path, analyzing the path and heading changes of the robot, and dividing the global path into a plurality of phased paths; When the autonomous underwater robot is navigating, the obstacle risk degree of the surrounding environment, the relative stability of the water flow and the position change of the robot are analyzed respectively to obtain the risk warning degree of the autonomous underwater robot at the current moment; According to the risk warning degree and in combination with the phased path, adjusting the local path of the autonomous underwater robot at the current moment; When the autonomous underwater robot is navigating, it uses sonar detectors to obtain feedback on obstacles in the surrounding environment at the current moment and mark the direction of the obstacles; Analyze the ratio of the number of marked directions to the total number of all detected directions to obtain the obstacle risk of the surrounding environment; When the autonomous underwater robot is navigating, the water flow velocity at the current moment and the water flow velocity at the previous moment are obtained through the flow velocity sensor; Analyze the standard deviation of the difference between the current water flow velocity and the previous water flow velocity to obtain the relative stability of the current water flow; When the autonomous underwater robot is navigating, obtain the position coordinates of the robot at the current moment and the previous moment; The Euclidean distance between the current position coordinates and the previous position coordinates is analyzed to obtain the position change of the robot at the current moment.

2. The method for planning a navigation path of an autonomous underwater robot according to claim 1, characterized in that: Based on the global path, the path and heading changes of the robot are analyzed, and the global path is divided into a plurality of phased paths to obtain phased paths, including: Obtaining path points of the global path; Analyze the azimuth deflection of the path points to obtain key points of the global path; According to the key points, the global path is divided into a plurality of stage paths to obtain stage paths.

3. The method for planning a navigation path for an autonomous underwater robot according to claim 2, characterized in that: Analyze the azimuth deflection of the path point to obtain the key points of the global path, including: Obtaining coordinate information of the path point and its neighboring path points; Based on the coordinate information, analyzing the standard deviation of the displacement difference between the path point and its neighboring path points in a coordinate direction to obtain the azimuth deflection degree of the path point; According to the azimuth deflection of all the path points, an azimuth deflection curve is drawn, and all maximum value points of the azimuth deflection curve are obtained as key points of the global path.

4. The method for planning a navigation path of an autonomous underwater robot according to claim 1, characterized in that: According to the risk warning degree and in combination with the phased path, the local path of the autonomous underwater robot at the current moment is adjusted, including: Set risk warning thresholds; Determining whether the risk warning degree is greater than or equal to the risk warning threshold; If yes, taking the current position of the autonomous underwater robot as the local starting point, taking the end point of the staged path where the current position of the autonomous underwater robot is located as the local target point, and using a local path planning algorithm to adjust the local path of the autonomous underwater robot from the local starting point to the local target point; If not, the autonomous underwater vehicle continues to navigate according to the global path at the current moment.

5. The method for planning a navigation path of an autonomous underwater robot according to claim 1, characterized in that: Get the global path of the autonomous underwater robot from the starting point to the target point, including: Based on the underwater static map, the global path of the autonomous underwater robot from the starting point to the target point is obtained through the global path planning algorithm.

6. An autonomous underwater robot navigation path planning device, characterized in that: The device comprises: a memory and a processor, wherein: The memory is used to store program codes; The processor is configured to read the program code stored in the memory and execute the method according to any one of claims 1 to 3.

7. An autonomous underwater robot navigation path planning system, characterized in that: The system comprises: A global path acquisition module is used to obtain the global path of the autonomous underwater robot from the starting point to the target point; A phased path division module, used for analyzing the path and heading changes of the robot based on the global path, and dividing the global path into a plurality of phased paths; The risk warning degree analysis module is used to analyze the obstacle risk degree of the surrounding environment, the relative stability of the water flow and the position change of the robot at the current moment when the autonomous underwater robot is navigating, and obtain the risk warning degree of the autonomous underwater robot at the current moment; When the autonomous underwater robot is navigating, it uses sonar detectors to obtain feedback on obstacles in the surrounding environment at the current moment and mark the direction of the obstacles; Analyze the ratio of the number of marked directions to the total number of all detected directions to obtain the obstacle risk of the surrounding environment; When the autonomous underwater robot is navigating, the water flow velocity at the current moment and the water flow velocity at the previous moment are obtained through the flow velocity sensor; Analyze the standard deviation of the difference between the current water flow velocity and the previous water flow velocity to obtain the relative stability of the current water flow; When the autonomous underwater robot is navigating, obtain the position coordinates of the robot at the current moment and the previous moment; Analyze the Euclidean distance between the current position coordinates and the previous position coordinates to obtain the position change of the robot at the current moment; The local path adjustment module is used to adjust the local path of the autonomous underwater robot at the current moment according to the risk warning degree and in combination with the phased path.

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