Underwater vehicle route and mission area conflict detection method

Abstract

The application relates to the field of underwater carrier navigation, and discloses a kind of underwater carrier route and task area conflict detection method.For the problem of high time complexity and low efficiency of route conflict detection algorithm, a dynamic efficient route conflict detection method is proposed.Through pre-processing conflict detection, the possible conflict plan is gradually calculated, a large number of objects without conflict possibility are excluded, the conflict detection processing calculation amount is reduced, and the processing time is saved.The method is suitable for underwater carrier route and task area conflict detection, has high availability and strong practicability.

Description

Technical Field

[0001] This invention belongs to the field of underwater vehicle navigation, specifically relating to a method for detecting conflicts in underwater vehicle routes and mission areas. Background Technology

[0002] Exploring and understanding the ocean is a prerequisite for its development, utilization, and protection. Underwater vehicles provide crucial support for marine environmental exploration and military reconnaissance. In accordance with safe navigation requirements, conflict detection of planned routes is essential for the successful completion of missions by underwater vehicles.

[0003] Conflict detection primarily involves both temporal and spatial conflicts, both of which must be considered simultaneously. Temporal conflicts require comparing the start and end times of various flight plans, while spatial conflicts require analyzing and processing the flight routes to check for any conflicts. When conflicts exist in both time and space, flight plans are highly likely to clash.

[0004] Flight route conflict detection methods can be divided into computational methods and simulation methods. The computational method, also known as static detection, refers to, after obtaining flight route parameters, using a mathematical model of the flight route and considering factors such as time, first eliminating plans that are completely impossible to cause conflict, and then progressively calculating the plans that may cause conflict, ultimately obtaining information such as conflict points and conflict times. The simulation method, also known as dynamic detection, refers to, through simulation and deduction, first determining the length of the simulation time slice, and then progressively deduce each time slice to check whether there are conflict points in each time slice. Summary of the Invention

[0005] To address the problems existing in the background art, the present invention provides a method for detecting conflicts in the route and mission area of ​​an underwater vehicle, which includes the following steps:

[0006] S1. Route Conflict Detection: Detects and judges conflicts based on the two-dimensional planar information after latitude and longitude projection transformation;

[0007] S2. Mission Area Conflict Detection: Detects the corresponding mission areas of different underwater vehicles to avoid overlap or distances less than the safe distance at the same time.

[0008] The specific process of step S1 includes:

[0009] P1. Import the longitude, latitude, turning time, and heading of each waypoint in the route plan table, and set the safe distance between routes;

[0010] P2. Iterate through the voyage plans pairwise and find the intersection of the voyage times of the two voyage plans. If the intersection is empty, there is no conflict; otherwise, proceed to the following steps.

[0011] P3. Take the route segments from these two flight plans and check them respectively. Find the intersection of the flight times of the two route segments. If the intersection is empty, there is no conflict.

[0012] P4. Convert the latitude and longitude coordinates of the two route segments into two-dimensional plane coordinates through projection;

[0013] P5. Determine if there is a possibility of a conflict in the coordinate ranges of the two route segments;

[0014] P6. Select potentially conflicting route segments for detailed detection. Choose potentially conflicting route segments AB and CD, and let the travel times for route segments AB and CD be respectively... , ,set up and The intersection is The simulation time is calculated using a dynamic detection method. If the distance between inner route segments is less than the safe distance, record the position and coordinates of the first point that is less than the safe distance and the last point that is less than the safe distance. This segment is the conflict segment.

[0015] The specific process of step S2 includes:

[0016] Q1. Import information for each task area and set the safe distance between task areas;

[0017] Q2. Determine whether two task regions overlap in time;

[0018] Q3. Convert latitude and longitude coordinates into two-dimensional plane coordinates through projection;

[0019] Q4. Determine the coordinate range of the task area. If there is a possibility of conflict between two coordinate ranges, select this task area as the suspected conflict area.

[0020] Q5. Calculate whether the task areas overlap;

[0021] Q6. Are the calculation task areas too close together?

[0022] Q7. Output the conflicting task areas and their corresponding times.

[0023] The beneficial effects achieved by this invention are as follows:

[0024] This invention addresses the problems of high time complexity and low efficiency in conflict detection algorithms by adopting a dynamic detection method. It is applicable to conflict detection in the course and mission area of ​​underwater vehicles, with low time complexity, high availability, and strong practicality. Attached Figure Description

[0025] Figure 1 This is a flowchart of the flight path conflict detection algorithm.

[0026] Figure 2 Map showing the coordinate range of the two route segments

[0027] Figure 3 This is a flowchart of the task area conflict detection algorithm.

[0028] Figure 4 This is a diagram showing the coordinate range of the polygon and the polygon task area.

[0029] Figure 5 This is a diagram showing the coordinate range of the polygonal and circular task areas.

[0030] Figure 6 This is a diagram showing the coordinate range of the circular task area. Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Reference Figure 1-6 The route conflict detection includes the following steps:

[0033] (1) Import data: Import the longitude, latitude, turning time and heading of each waypoint in the route plan table, and set the safe distance between routes.

[0034] (2) Determine whether the two routes have an intersection in time: The mathematical expression for this determination is as follows:

[0035]

[0036] in, , , Let and represent the start and end times of navigation plan A and navigation plan B, respectively. If the above formula does not hold true, then navigation plan A and navigation plan B do not conflict.

[0037] (3) Take the route segments separately and determine whether there is any overlap in time: For a set of comparison route segments of two routes, if one plan A has passed through the corresponding route segment and the other plan B has just started to enter the corresponding route segment, then there is no conflict between the two route segments.

[0038] (4) Use Mercator projection to convert latitude and longitude coordinates into two-dimensional plane coordinates.

[0039] (5) Determine whether the approximate ranges of the two route segments overlap: Generate a buffer zone for a route. Considering the need to maintain a safe distance between routes, a safe distance must be left, such as... Figure 2 As shown in region G, it is clear that the area outside region G is a safe zone, while conflicts may occur within region G. If this region overlaps with the coordinate range of another flight segment (such as...), then... Figure 2 If there is overlap (as shown in region H), continue with the following steps. If there is no overlap, it means there is no conflict.

[0040] (6) After the above steps, select potentially conflicting route segments for detailed testing. Take two potentially conflicting route segments AB and CD, assuming the travel times for route segments AB and CD are respectively... , ,set up and The intersection is ,but This refers to the length of the time slice in the simulation. Next, we will discuss time. Situation inside:

[0041] In time In the process, the step size is set to 1 second to determine the position and distance between the two underwater vehicles located on the route segments AB and CD.

[0042] Assume waypoint A Axis coordinates The axis coordinates, arrival time, heading angle, and speed are as follows: , , , , ;

[0043] waypoint B Axis coordinates The axis coordinates, arrival time, heading angle, and speed are as follows: , , , , ;

[0044] waypoint C Axis coordinates The axis coordinates, arrival time, heading angle, and speed are as follows: , , , , ;

[0045] waypoint D Axis coordinates The axis coordinates, arrival time, heading angle, and speed are as follows: , , , , .

[0046] when At that time, the position coordinates of the underwater vehicle on the route segment AB can be expressed as: The position coordinates of the underwater vehicle on the route segment CD can be represented as follows: Furthermore, the distance between the two underwater vehicles is... ,like This indicates there is no conflict. Then, record the time and location of the conflict and output it.

[0047] The task area conflict detection includes the following steps:

[0048] (1) Import data: Import relevant information from the flight plan table, including the start time and end time of each flight plan within the mission area, and obtain mission area information. If the file contains vertex latitude and longitude information, it is determined to be a polygonal area (including rectangles). If the file contains latitude and longitude coordinates and radius, it is determined to be a circular area. Set the safe distance between mission areas.

[0049] (2) Determine whether there is an overlap in time between two task regions: Task region conflict detection is performed on a two-dimensional plane. First, determine whether there is an overlap in time between the two groups of task regions A and B. If there is no overlap in time between the two groups of tasks, then a conflict is impossible.

[0050] (3) Convert latitude and longitude coordinates into two-dimensional plane coordinates: Convert latitude and longitude coordinates into two-dimensional plane coordinates through Mercator projection.

[0051] (4) Calculate whether the task regions overlap: Considering that the task regions may be polygons (including rectangles) or circles, we will discuss four cases:

[0052] a. The task regions extracted from both Group A and Group B are polygons:

[0053] Method: Let two polygons be labeled a and b. First, calculate whether the areas containing the two polygons intersect (e.g., ...). Figure 4(As shown in regions A and B). If there is an intersection, determine whether each vertex of polygon a is inside polygon b, whether each vertex of polygon b is inside polygon a, whether each vertex of polygon a is on any line segment of polygon b, and whether each vertex of polygon b is on any line segment of polygon a. If the result is no, it means that the two regions do not intersect, and it is necessary to further determine whether the distance between the two regions is less than the safe distance. Traverse each edge of the two polygons and calculate the intersection point. The method to determine whether the distance between the two regions is less than the safe distance is: calculate the distance from each vertex of polygon b to each edge of polygon a, and whether the distance from each vertex of polygon a to each edge of polygon b is greater than the safe distance. If there is a value less than the safe distance, issue a prompt that the two task regions are too close.

[0054] The method for determining whether a point is inside a polygon is as follows: Assume the vertices of the polygon are... , , ..., The point to be judged is ,beg:

[0055]

[0056] from Departure, painted A ray with slope, by and Given the selection criteria, this ray will not intersect any vertex of the polygon. Let's take another point on the ray:

[0057]

[0058] Provable points Outside the polygonal region, the detection point Does it exist within a polygon and can be converted into a computational line segment? The number of intersection points with each side of the polygon. If the number of intersection points is odd, then the point... Inside the polygon; if the number of intersection points is even, then the point It is not inside the polygon.

[0059] b. The task area selected from group A is a polygon, and the task area selected from group B is a circle.

[0060] Method: First, calculate whether the areas of the two task regions overlap (e.g., ...). Figure 5 (As shown in regions C and D). If the ranges intersect, traverse each side of the polygon, calculate whether it intersects with the circular region and the circular buffer region, and calculate the intersection point. The method is as follows: first determine whether the center of the circle is inside the polygon. If it is inside the polygon, there is a conflict. If it is not inside the polygon, calculate the minimum distance from the center of the circle to each line segment.

[0061] c. The task area selected from group A is circular, while the task area selected from group B is polygonal.

[0062] The method is the same as above.

[0063] d. The task areas selected from both Group A and Group B are circular.

[0064] Method: First, calculate whether the areas of the two task regions overlap (e.g., ...). Figure 6 (As shown in regions E and F). If the ranges intersect, calculate the distance between the centers and determine if it is less than the sum of the radii. If it is less than the sum of the radii plus the safety distance.

[0065] (5) Output the conflicting task areas and corresponding times.

[0066] The above description is merely 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 principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting conflicts in the flight path and mission area of ​​an underwater vehicle, characterized in that, Includes the following steps: S1. Route Conflict Detection: Conflict detection and judgment are performed on the two-dimensional planar information after latitude and longitude projection transformation; the specific process of step S1 includes: P1. Import the longitude, latitude, turning time, and heading of each waypoint in the route plan table, and set the safe distance between routes; P2. Iterate through the voyage plans pairwise and find the intersection of the voyage times of the two voyage plans. If the intersection is empty, there is no conflict; otherwise, proceed to the following steps. P3. Take the route segments from these two flight plans and check them respectively. Find the intersection of the flight times of the two route segments. If the intersection is empty, there is no conflict. P4. Convert the latitude and longitude coordinates of the two route segments into two-dimensional plane coordinates through projection; P5. Determine if there is a possibility of conflict between the coordinate ranges of the two route segments: Generate a buffer range area for one route segment. Considering that a safe distance should be maintained between routes, a safe distance is left when generating the buffer range area. This area is denoted as area G. The area outside area G is a safe area. Conflicts may occur within area G. If area G overlaps with the coordinate range area H of another route segment, continue with the following steps. If there is no overlap, it means there is no conflict. P6. Select potentially conflicting route segments for detailed detection. Take potentially conflicting route segments AB and CD. Let the time to pass through route segments AB and CD be [TI,TK] and [TE,TF], respectively. Let the intersection of [TI,TK] and [TE,TF] be [TR,TS]. Use a dynamic detection method with a step size of 1 second to calculate the distance between route segments within the simulation time [TR,TS]. If it is less than the safe distance, record the position and coordinates of the first point less than the safe distance and the last point less than the safe distance. This segment is the conflict segment. S2. Mission Area Conflict Detection: Detect the corresponding mission areas of different underwater vehicles to avoid overlap or distances less than the safe distance at the same time; the specific process of step S2 includes: Q1. Import information for each task area and set the safe distance between task areas; Q2. Determine whether two task regions overlap in time; Q3. Convert latitude and longitude coordinates into two-dimensional plane coordinates through projection; Q4. Determine the coordinate range of the task area. If there is a possibility of conflict between two coordinate ranges, select this task area as the suspected conflict area. Q5. Calculate whether the task areas overlap; Q6. Calculate whether the task areas are too close: Traverse each edge of the two polygons, calculate the distance from each vertex of polygon b to each edge of polygon a, and the distance from each vertex of polygon a to each edge of polygon b. If there is a value less than the safe distance, it is determined that the two task areas are too close and there is a conflict. Q7. Output the conflicting task areas and their corresponding times.

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