Method and device for autonomous unmanned aerial vehicles to traverse obstacles and adapt to ocean current direction

Abstract

This invention discloses an adaptive obstacle avoidance method and apparatus for autonomous unmanned aerial vehicles (UAVs) based on ocean current direction, belonging to the field of path planning. It mainly rotates the coordinate system based on the ocean current direction and places the starting point of the UAV at the leftmost / rightmost edge point or edge line of the search area along the X-axis. It then sequentially determines whether movement is possible in the vertical and horizontal directions. If so, it moves forward one step; otherwise, it finds the nearest point to the current point as the new starting point and continues traversing until the entire search area has been traversed. This path planning method effectively reduces the path length in the cross-current direction and improves path planning accuracy.

Description

Technical Field

[0001] This invention relates to the field of underwater path planning technology, and more specifically to an adaptive ocean current direction autonomous unmanned vehicle obstacle avoidance search algorithm and device. Background Technology

[0002] Autonomous underwater vehicles (AUVs) are widely used in military and civilian fields such as seabed topography mapping, hydrological information collection, and mine countermeasures. Appropriate traversal path planning algorithms can effectively solve the problem of searching for coverage areas in operational tasks. However, existing algorithms, such as those based on population hyperheuristics, data-driven approaches, or bidirectional search, are relatively complex. Furthermore, considering the underactuated nature of AUVs, their path-tracking accuracy is significantly reduced when subjected to underwater currents, especially crosscurrents.

[0003] Therefore, how to propose a simple obstacle avoidance search algorithm for unmanned autonomous vehicles that can adapt to the direction of ocean currents, and provide a technical foundation for the high airworthiness and high followability of the search path, is a problem that needs to be solved urgently. Summary of the Invention

[0004] In view of this, the present invention provides an adaptive ocean current direction autonomous unmanned vehicle traversal obstacle avoidance search algorithm and device, which enables the autonomous unmanned vehicle to perform main planning in a collinear manner with the ocean current, minimizing the path length in the cross-current direction, and providing a technical basis for high airworthiness and high followability of the search path.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An adaptive obstacle avoidance method for autonomous unmanned vehicles (UAVs) based on ocean current direction includes the following steps:

[0007] S1. Obtain the search area and ocean current direction;

[0008] S2. Based on the search area and the direction of the ocean current, rotate the coordinate system of the autonomous unmanned vehicle to make the initial search direction of the autonomous unmanned vehicle parallel to the direction of the ocean current.

[0009] S3. Place the starting point of the autonomous unmanned vehicle at the leftmost / rightmost edge point or edge line of the search area in the X-axis direction;

[0010] S4. Following the principle of traversing without repetition, sequentially determine whether movement is possible in the up / down and left / right directions.

[0011] If so, move forward one step; otherwise, find the point closest to the current point as the new starting point.

[0012] S5. Repeat step S4 until the search area has been traversed.

[0013] To further optimize the above technical solution, in step S1, when the search area includes an obstacle area, if the starting point of the autonomous unmanned vehicle is located at the leftmost end of the search area, the judgment order is left, up / down / up, right; if the starting point of the autonomous unmanned vehicle is located at the rightmost end of the search area, the judgment order is right, up / down / up, left.

[0014] To further optimize the above technical solution, the route is directly output after the traversal is completed.

[0015] To further optimize the above technical solution, in step S4, the initial search direction is south / north, and during traversal, it is determined whether the north-south direction and the east-west direction can be moved.

[0016] On the other hand, the present invention provides an adaptive ocean current direction autonomous unmanned vehicle obstacle avoidance device, wherein the device includes:

[0017] The data acquisition module is used to acquire the search area and ocean current direction;

[0018] The coordinate system transformation module is used to rotate the coordinate system of the autonomous unmanned vehicle according to the search area and the direction of the ocean current, so that the initial search direction of the autonomous unmanned vehicle is parallel to the direction of the ocean current.

[0019] The starting point setting module is used to place the starting point of the autonomous unmanned vehicle at the leftmost / rightmost edge point or edge line of the search area in the X-axis direction;

[0020] The path traversal module is used to determine whether the path can be moved in the up or down direction, and then in the left or right direction, according to the principle of non-repeating traversal. If it can be moved, the path moves forward by one step; otherwise, the path finds the point closest to the current point as the new starting point.

[0021] The present invention also provides an electronic device comprising a processor and a memory, the memory storing machine-executable instructions executable by the processor, the processor executing the machine-executable instructions to implement the adaptive ocean current direction autonomous unmanned vehicle obstacle avoidance method described above.

[0022] As can be seen from the above technical solution, compared with the prior art, this application first detects the direction of the ocean current and performs coordinate transformation on the boundary between the search area and the obstruction area. Then, it uses the publicly disclosed adaptive ocean current-oriented autonomous unmanned vehicle traversal obstacle avoidance search algorithm to plan the navigation path of the autonomous unmanned vehicle. The traversal method disclosed in this invention enables the autonomous unmanned vehicle to mainly plan in a collinear manner with the ocean current, reducing the path length in the cross-current direction, thereby improving the accuracy of the tracking path. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a flowchart of the obstacle avoidance search algorithm for autonomous unmanned vehicles that adapt to the direction of ocean currents in this invention.

[0025] Figure 2 A traversal flowchart of a simulation embodiment of the present invention is provided;

[0026] Figure 3 This is the initialized search area provided by the present invention;

[0027] Figure 4 This is the converted search area provided by the present invention;

[0028] Figure 5 A comparison diagram of the search areas before and after the conversion provided by this invention;

[0029] Figure 6 This is the path graph calculated according to the search algorithm of this invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings.

[0031] The following description, provided with reference to the accompanying drawings, is intended to aid in a full understanding of embodiments of the present disclosure as defined by the claims and their equivalents. Various specific details are included to aid understanding, but these details are to be considered exemplary only. Therefore, those skilled in the art will recognize that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Furthermore, for clarity and brevity, descriptions of well-known functions and structures are omitted.

[0032] The terms and words used in the following description and claims are not limited to their literal meaning, but are intended solely by the inventors to achieve a clear and consistent understanding of this disclosure. Therefore, those skilled in the art will understand that the following description of various embodiments of this disclosure is provided for illustrative purposes only and is not intended to limit the purpose of this disclosure as defined by the claims and their equivalents.

[0033] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0034] This invention discloses an adaptive ocean current direction-based obstacle avoidance method for autonomous unmanned vehicles, such as... Figure 1 As shown, it includes the following steps:

[0035] S1. Obtain the search area and ocean current direction; whereby the ocean current direction can be any direction within the xoy horizontal plane. Furthermore, the ocean current direction can be obtained through ocean current direction measurement equipment on the autonomous unmanned vehicle, such as ADCP.

[0036] S2. Based on the search area and the direction of the ocean current, rotate the coordinate system of the autonomous unmanned vehicle to make the initial search direction of the autonomous unmanned vehicle parallel to the direction of the ocean current.

[0037] In one embodiment, a new equivalent search area and navigation obstruction zone are determined by the following coordinate transformation method, where θ is the direction of ocean current.

[0038]

[0039] S3. To avoid repeated coverage of the area search, this application places the starting point of the autonomous unmanned vehicle at the leftmost / rightmost edge point or edge line of the search area in the X-axis direction.

[0040] S4. Following the principle of non-repeated traversal, it is determined whether the up and down and left and right directions can be moved in turn. This application limits the determination of the up and down direction first, and then the left and right directions. This can ensure that the autonomous unmanned vehicle prioritizes searching in the direction of the ocean current, either facing the current or with the current, thereby reducing the path length in the cross current direction.

[0041] Furthermore, if it is possible to move, it moves forward one step; if it is not possible to move, it finds the point closest to the current point as the new starting point.

[0042] In addition, the principle of non-repeated traversal means not considering the direction from which the autonomous unmanned vehicle came, so as to avoid repeated traversal of the area caused by backtracking.

[0043] In one embodiment, if the autonomous unmanned vehicle starts from the leftmost end of the search area, it can first determine the up and down direction, and then determine whether it can move to the right, i.e., up, down and right, or down, up and right; if it starts from the rightmost end of the search area, it can first determine the up and down direction, and then determine whether it can move to the left. The specific determination order can be up, down and left, or down, up and left.

[0044] S5. Repeat step S4 until the search area has been traversed.

[0045] To further optimize the above technical solution, in step S1, when the search area includes an obstacle area, if the starting point of the autonomous unmanned vehicle is located at the leftmost end of the search area, the judgment order is left, up / down / down-up, right.

[0046] If the starting point of the autonomous unmanned vehicle is located at the rightmost end of the search area, the judgment order is right, up / down / down / up, left.

[0047] To further optimize the above technical solution, the route is directly output after the traversal is completed.

[0048] To further optimize the above technical solution, in step S4, the initial search direction can be configured as south / north, and during traversal, it is determined whether the north-south direction and the east-west direction can be moved.

[0049] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to simulation embodiments.

[0050] In one embodiment, the specific steps are as follows: Figure 2 As shown:

[0051] 1. Initialize parameters;

[0052] 2. Read the search area and navigation obstruction area, measure the direction of the ocean current, and rotate the coordinate system according to the direction of the ocean current so that the initial search point faces north.

[0053] 3. Record the current location;

[0054] 4. Determine if it is possible to move westward. If so, move forward one step to reach the new position; if not, proceed to step 5.

[0055] 5. Determine if it is possible to move south. If yes, move forward one step to reach the new position; if not, proceed to step 6.

[0056] 6. Determine if it is possible to move north. If yes, move forward one step to reach the new position; if not, proceed to step 7.

[0057] 7. Determine if it is possible to move eastward. If so, move one step forward to reach the new location; if not, find a new starting point and continue planning, then go to step 4.

[0058] 8. Determine if the new position has been traversed. If yes, output the route; otherwise, go to step 3.

[0059] In one embodiment, the initialization area includes a search area, a navigation obstruction area, and an area with ocean current direction such as... Figure 3 As shown; rotate the coordinate system, the transformed search area is, for example... Figure 4 As shown; comparison images before and after conversion are as follows. Figure 5 As shown,

[0060] The path calculated by the autonomous unmanned vehicle's obstacle avoidance search algorithm based on the adaptive ocean current direction is as follows: Figure 6 As shown in the diagram. Here, 'o' represents the starting point, '△' represents the ending point, and red * and blue * represent points that cannot move eastward and new starting points, respectively. The results demonstrate that the algorithm proposed in this patent has good coverage and good upstream / downstream routes.

[0061] On the other hand, the present invention provides an autonomous unmanned vehicle obstacle avoidance device that adapts to the direction of ocean currents, wherein the device includes:

[0062] The data acquisition module is used to acquire the search area and ocean current direction;

[0063] The coordinate system transformation module is used to rotate the coordinate system of the autonomous unmanned vehicle according to the search area and the direction of the ocean current, so that the initial search direction of the autonomous unmanned vehicle is parallel to the direction of the ocean current.

[0064] The starting point setting module is used to place the starting point of the autonomous unmanned vehicle at the leftmost / rightmost edge point or edge line of the search area in the X-axis direction;

[0065] The path traversal module is used to determine whether the path can be moved in the up or down direction, and then in the left or right direction, according to the principle of non-repeating traversal. If it can be moved, the path moves forward by one step; otherwise, the path finds the point closest to the current point as the new starting point.

[0066] The present invention also provides an electronic device comprising a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the adaptive ocean current direction autonomous unmanned vehicle obstacle avoidance method described above.

[0067] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0068] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for autonomous unmanned aerial vehicles to traverse and avoid obstacles based on adaptive ocean current direction, characterized in that, Includes the following steps: S1. Obtain the search area and ocean current direction; S2. Based on the search area and the direction of the ocean current, rotate the coordinate system of the autonomous unmanned vehicle to make the initial search direction of the autonomous unmanned vehicle parallel to the direction of the ocean current; specifically, determine the new equivalent search area and navigation obstruction area through the following coordinate transformation method, where θ is the direction of the ocean current. ； S3. Place the starting point of the autonomous unmanned vehicle at the leftmost / rightmost edge point or edge line of the search area in the X-axis direction; S4. Following the principle of non-repeated traversal, first determine whether the up and down directions are possible, then determine whether the left and right directions are possible. If so, move forward one step; otherwise, find the point closest to the current point as the new starting point. S5. Repeat step S4 until the search area has been traversed.

2. The method for adaptive ocean current direction-based obstacle avoidance by an autonomous unmanned vehicle according to claim 1, characterized in that, In step S1, when the search area includes an obstacle area, if the starting point of the autonomous unmanned vehicle is located at the leftmost end of the search area, the judgment order is left, up / down / up, right; if the starting point of the autonomous unmanned vehicle is located at the rightmost end of the search area, the judgment order is right, up / down / up, left.

3. The method for adaptive ocean current direction-based obstacle avoidance by an autonomous unmanned vehicle according to claim 1, characterized in that, After the traversal is complete, the route is output directly.

4. The method for adaptive ocean current direction-based obstacle avoidance by an autonomous unmanned vehicle according to claim 1, characterized in that, In step S4, the initial search direction is configured as north / south, and during traversal, it is determined whether the north-south and east-west directions can be moved.

5. An obstacle avoidance device for an autonomous unmanned aerial vehicle that adapts to the direction of ocean currents, characterized in that, The device includes: The data acquisition module is used to acquire the search area and ocean current direction; The coordinate system transformation module is used to rotate the coordinate system of the autonomous unmanned vehicle according to the search area and the direction of the ocean current, so that the initial search direction of the autonomous unmanned vehicle is parallel to the direction of the ocean current; specifically, the new equivalent search area and navigation obstruction area are determined by the following coordinate transformation method, where θ is the direction of the ocean current. ； The starting point setting module is used to place the starting point of the autonomous unmanned vehicle at the leftmost / rightmost edge point or edge line of the search area in the X-axis direction; The path traversal module is used to determine whether the path can be moved in the up or down direction, and then in the left or right direction, according to the principle of non-repeating traversal. If it can be moved, the path moves forward by one step; if not, the path finds the point closest to the current point as the new starting point, until the search area has been traversed.

6. An electronic device, characterized in that, It includes a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the adaptive ocean current direction autonomous unmanned vehicle obstacle avoidance method according to any one of claims 1 to 4.

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