Mountain path planning method based on dichotomy

Abstract

The invention discloses a mountain land path planning method based on a bisection method. The method comprises the following steps: determining a starting point and an ending point on a three-dimensional terrain model; selecting a plurality of points on a terrain cross section of a midpoint between the starting point and the ending point as midpoints of necessary paths; determining a midpoint of an inevitable path corresponding to the minimum gradient value; carrying out bisection calculation on two sections of lines among a midpoint, a starting point and an end point of an inevitable path, and gradually determining each path point on the lines; connecting the approach points into a polyline, and equally dividing the polyline to obtain sampling points; deleting a middle point in the three sampling points to generate a regeneration route; and cyclically sampling the regeneration routes according to different equipartition numbers to generate a final route. The problem that the planning structure is not accurate enough due to the fact that existing complex terrain path planning cannot give consideration to gradient differences of different areas is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of path planning, and in particular to a mountain path planning method based on dichotomy. Background Art

[0002] When planning a route in complex terrain (such as mountainous landscapes and mountain roads), most people consider factors such as route length and traffic conditions to select the best travel route. However, the slopes of mountains vary greatly. If the slope differences in different areas are not considered when planning a route in complex terrain, the planning results will be inaccurate. Summary of the invention

[0003] In order to overcome the defects of the existing technology, a mountain path planning method based on dichotomy is provided to solve the problem that the existing complex terrain path planning cannot take into account the slope differences in different areas, resulting in inaccurate planning structure.

[0004] To achieve the above purpose, a mountain path planning method based on dichotomy is provided, which includes the following steps:

[0005] Determine the path start point and path end point on the three-dimensional terrain model;

[0006] Selecting a plurality of points on the terrain cross section at the midpoint between the starting point of the path and the end point of the path as the midpoints of the necessary path;

[0007] Taking the sum of the slopes of the midpoint of the necessary path, the starting point of the path, and the end point of the path as the slope value, determining a midpoint of the necessary path corresponding to the minimum slope value;

[0008] Performing binary calculation on the two sections of the route between the midpoint of the one necessary path and the starting point of the path and the end point of the path, and successively determining each waypoint on the route;

[0009] Connecting the waypoints into a polyline, and equally dividing the polyline to obtain sampling points;

[0010] When the straight-line distance between the first and last sampling points of three adjacent sampling points is less than the sum of the straight-line distances between two adjacent sampling points of the three sampling points, and the slope between the first and last sampling points is less than a preset slope, the middle point of the three sampling points is deleted to generate a rebirth route;

[0011] The above rebirth routes are sampled cyclically according to different equal division quantities to generate the final route.

[0012] Furthermore, the binary calculation is performed at least seven times.

[0013] The beneficial effect of the present invention is that the mountain path planning method based on dichotomy of the present invention, through the spatial terrain model generated by geological survey data, can plan a path plan with a relatively gentle slope and a short distance based on the set starting point and end point, and in the field of engineering construction, provide a more accurate reference for mountain road planning and landscape road planning.

[0014] In addition, the mountain path planning method based on dichotomy of the present invention combined with the spatial grid data generated by reverse modeling can quickly plan several optimal paths with relatively gentle slopes and short distances. In the field of navigation planning, especially in areas such as deserts where the terrain changes greatly due to seasonal influences, off-road paths can be planned for vehicles or personnel without reference to historical paths. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0016] Figures 1 to 9 FIG. 4 is a schematic diagram of binary calculation logic of an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0018] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0019] The present invention provides a mountain path planning method based on dichotomy, comprising the following steps:

[0020] S1. Determine a path start point and a path end point on a three-dimensional terrain model.

[0021] S2. Select multiple points on the terrain cross section at the midpoint between the path starting point and the path end point as the midpoints of the necessary path.

[0022] S3. Taking the sum of the slopes of the midpoint of the necessary path and the starting point and the end point of the path as the slope value, determine a midpoint of the necessary path corresponding to the minimum slope value.

[0023] S4. Perform binary calculation on two sections of a route between a midpoint of a necessary path and the starting point and the end point of the path, and successively determine each waypoint on the route.

[0024] As a preferred implementation, the binary calculation is performed at least seven times.

[0025] Use the successive dichotomy method to select several points on the terrain cross section of the midpoint between the starting point and the end point of the path as the midpoint of the necessary path (adjust the preset range of the necessary midpoints, the closer the set range is to the line connecting the starting point and the end point, the stronger the trend from the starting point to the end point, and vice versa, the weaker the trend from the starting point to the end point, and the greater the freedom of path selection), use the sum of the slopes from the midpoint of the necessary path to the starting point and the end point of the path as a reference, and select the minimum slope and the corresponding midpoint of the necessary path.

[0026] The route is divided into two parts at the midpoint of the necessary path, and then the two subdivided routes are divided into two parts, and the passing points of each path are gradually determined. The binary division is repeated n times to obtain 2 n A polyline consisting of subdivided line segments.

[0027] S5. Connect each path point into a polyline, and evenly divide the polyline to obtain sampling points.

[0028] S6. When the straight-line distance between the first and last sampling points of three adjacent sampling points is less than the sum of the straight-line distances between two adjacent sampling points of the three sampling points, and the slope between the first and last sampling points is less than a preset slope, delete the middle point of the three sampling points to generate a rebirth route.

[0029] Specifically, each passing point is connected into a polyline, and the polyline is evenly divided to obtain sampling points such as O1, O2, O3, ... m …O n-1 ,O n , filter O m O m+2 The straight-line distance between the two points is less than the set value and the slope between the two points is less than the specified value. m+1 Delete the points and reconnect the remaining points into polylines.

[0030] For example, passing through three sampling points ABC, if the straight-line distance between sampling points AC is less than sampling point AB + sampling point BC, and the slope between sampling points AC is less than the preset slope, sampling point B is considered to be a non-essential waypoint and is deleted.

[0031] S7. Circularly sample the above rebirth routes according to different equal-division quantities to generate a final route.

[0032] According to different averaging numbers (the number of samples per cycle ranges from S*2 n To 2 nThe linear interpolation decreases, and the larger the S value, the smaller the change to the original curve) Repeat the calculation of step S6 for the polyline, that is, perform cyclic sampling on the polyline, continuously simplify the polyline, eliminate the line segment cusps and self-intersecting line segments caused by the binary calculation, and make the path line segment straighter and smoother.

[0033] Reference Figures 1 to 9 As shown, in order to further illustrate the binary calculation logic in the mountain path planning method based on binary method of the present invention, the following embodiments are specifically cited for detailed description.

[0034] S10. See Figure 1 As shown, a starting point A0 and an end point B0 are set on the terrain surface model 1 .

[0035] S20. Project the line segment A0B0 onto the horizontal plane, and draw a straight line L0 perpendicular to A0B0 at the midpoint of the line segment A0B0.

[0036] S30, take several points O1, O on the straight line L 2, …,O n .

[0037] S40, see Figure 2 As shown, O1,O 2, …,O n Project onto the terrain surface to get the projection point.

[0038] S50, set O1,O 2, …,O n Connect point A0 and point B0 with line L A0O1 ,L A0O2 ,…L A0On With L B0O1 ,L B0O2 ,…L B0On .

[0039] S60, calculate the angle between each connecting line and the horizontal plane and

[0040] S70, take The corresponding O n Point is C0.

[0041] S80, see Figure 3 As shown, project the line segments A0C0 and B0C0 onto the horizontal plane, and draw straight lines L perpendicular to the line segments at the end points of the line segments. 1A With L 1B .

[0042] S90, see Figure 4 As shown, on the straight line L 1A With L 1BTake several points O1,O respectively 2, …,O n Project it onto the terrain surface and connect the line A0C0 and B0C0 and calculate the angle between the line and the horizontal plane.

[0043] S100, see Figure 5 As shown, take The corresponding O n Point C 1A ,Pick The corresponding O n Point C 1B .

[0044] S110, see Figure 6 As shown, we get line segment A0C 1A ,C 1A C0,C0C 1B ,C 1B B0.

[0045] S120, see Figure 7 As shown, perform steps 2-7 on the above line segments and select the middle point between each point.

[0046] S130, see Figure 8 As shown, the 8 subdivided line segments are obtained and then the calculations of steps S20 to S70 are performed.

[0047] S140, see Fig. 9 As shown, and so on, gradually subdivided line segments are obtained.

[0048] The mountain path planning method based on dichotomy of the present invention, through the spatial terrain model generated by geological survey data, can plan a path plan with a relatively gentle slope and a short distance based on the set starting point and end point, and provide a more accurate reference for mountain road planning and landscape road planning in the field of engineering construction.

[0049] In addition, the mountain path planning method based on dichotomy of the present invention combined with the spatial grid data generated by reverse modeling can quickly plan several optimal paths with relatively gentle slopes and short distances. In the field of navigation planning, especially in areas such as deserts where the terrain changes greatly due to seasonal influences, off-road paths can be planned for vehicles or personnel without reference to historical paths.

[0050] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. A mountain path planning method based on dichotomy, characterized in that: The following steps are involved: Determine the path start point and path end point on the three-dimensional terrain model; Selecting a plurality of points on the terrain cross section at the midpoint between the starting point of the path and the end point of the path as the midpoints of the necessary path; Taking the sum of the slopes of the midpoint of the necessary path, the starting point of the path, and the end point of the path as the slope value, determining a midpoint of the necessary path corresponding to the minimum slope value; Performing binary calculation on the two sections of the route between the midpoint of the one necessary path and the starting point of the path and the end point of the path, and successively determining each waypoint on the route; Connecting the waypoints into a polyline, and equally dividing the polyline to obtain sampling points; When the straight-line distance between the first and last sampling points of three adjacent sampling points is less than the sum of the straight-line distances between two adjacent sampling points of the three sampling points, and the slope between the first and last sampling points is less than a preset slope, the middle point of the three sampling points is deleted to generate a rebirth route; The above rebirth routes are sampled cyclically according to different equal division quantities to generate the final route.

2. The mountain path planning method based on dichotomy according to claim 1 is characterized in that: The binary calculation is performed at least seven times.

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