KR20190050575A - Flying path searching method for unmanned aerial vehicle - Google Patents

Abstract

A method for searching for a flight path of an unmanned aerial vehicle comprises: (a) a step of receiving map data or modeling data including a start point and a target point of the unmanned aerial vehicle; (b) a step of dividing the map data or modeling data into a plurality of cells having the same size; (c) a step of searching for a first path for arriving at the target point via the plurality of cells from the start point; and (d) a step of searching, using the first path, for a second path for arriving at the target point via the plurality of cells from the start point. Therefore, an objective of the present invention is to provide the method for searching the flight path of the unmanned aerial vehicle capable of optimizing a route searched by an existing route search algorithm such as an A* algorithm by a simple algorithm.

Description

[0001] FLYING PATH SEARCHING METHOD FOR UNMANNED AERIAL VEHICLE [0002]

The present invention relates to a method of searching a flight path of an unmanned airplane, and more particularly, to a method of searching a flight path of an unmanned airplane in which an obstacle is located on a path so that the flight can be performed with a shorter path.

1 shows an example of a simplified map when an obstacle is included in a flight path of an unmanned aerial vehicle.

As shown in FIG. 2, the flight path of a drone such as a general drone can not correctly display the shortest path according to the A * algorithm when there is an obstacle, and the unmanned airplane is likely to fly a long distance Big.

For reference, the algorithm uses a method of assigning a heuristic estimate to each vertex x, which is a rank value that estimates the best path through the vertex. This algorithm visits the vertex in order of this heuristic estimate.

In 1968 Peter Hart, Niels Nielsen, and Bert Ramrapp published a paper on the A algorithm. Using an A algorithm with an appropriate heuristic is optimized, which is called the Aceta algorithm.

In addition, there are disadvantages that route algorithm consumes computer resources, so it is necessary to present flight path of UAV by simple algorithm. In addition, if the path of the UAV is erroneously set, it may collide with an obstacle such as a building, resulting in a lot of human life and economic loss.

Korean Patent Laid-Open No. 10-2017-0030214: A recording medium on which a program for executing a moving path setting method of an unmanned aerial photographing vehicle and a moving path setting method of an unmanned aerial photographing vehicle is recorded.

An object of the present invention is to provide a method of searching a flight path of an unmanned airplane capable of optimizing a route searched by an existing route search algorithm such as an ATIA algorithm by a simple algorithm The purpose is to do.

The method includes: (a) receiving map data or modeling data including a start point and a target point of the unmanned airplane; (b) dividing the map data or modeling data into a plurality of cells of equal size; (c) searching for a primary path from the starting point to the target point via a plurality of cells; And (d) using the primary path to search for a secondary path arriving at the target via the plurality of cells from the starting point.

The step (d) may further comprise the steps of: (d-1) if there is a cell at the starting point of the cell, the target cell, and a plurality of cells passing through the primary path, ; (d-2) generating a set with two numbered combinations as elements, using numbered cells; (d-3) determining whether the set is an empty set; (d-4) If the set is not an empty set as a result of the judgment in the step (d-3), the element having the largest difference between the two numbers is selected. Selecting the element having the smallest minimum value among the numbers of the elements; And (d-5) searching for a linear path between two numbers included in the element selected in the step (d-4).

The step (d) may further include: (d-6) determining whether or not an obstacle exists in the straight path detected in step (d-5); And (d-7) removing an element selected in the step (d-4) from the set when an obstacle exists as a result of the determining in the step (d-6) After the completion of step (7), it is preferable to move to step (d-3). The step (d) may further comprise: (d-8) if there is no obstacle as a result of the determining in the step (d-6), determining that there is no obstacle between the two numbers included in the element selected in the step The primary path is deleted, a new path is added by connecting two numbers included in the element selected in the step (d-4), and an element including a number included in the added new path is added And removing the element from the set, wherein after the completion of the step (d-8), the step (d-7) is performed.

Preferably, if the set is an empty set as a result of the determination in the step (d-3), the path search is terminated.

In the step (c), an algorithm may be used.

According to the flight path searching method of the UAV of the present invention, it is possible to optimize the route searched in the existing route search algorithm such as the AceTa algorithm by a simple algorithm.

FIG. 1 is an illustration of a simplified map when an obstacle is included in the flight path of the unmanned aerial vehicle. FIG.
FIG. 2 is a block diagram of an unmanned aerial vehicle system according to a preferred embodiment of the present invention.
FIG. 3 is a flowchart illustrating a method of searching a flight path of a UAV according to a preferred embodiment of the present invention. FIG.
FIG. 4 is a diagram illustrating an example of a primary path search result by an Aceh algorithm; FIG.
5 is a flowchart of step S40.
6 is an exemplary diagram illustrating the result of applying step S40 to the primary search path of FIG.

Hereinafter, a method of searching a flight path of an unmanned aerial vehicle according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the following embodiments of the present invention are only for embodying the present invention and do not limit or limit the scope of the present invention. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.

2 is a block diagram of an unmanned aerial vehicle system 100 according to a preferred embodiment of the present invention.

2, the unmanned aerial vehicle system 100 according to the preferred embodiment of the present invention includes an unmanned air vehicle 10, a server 20, and a user terminal 30.

The user terminal 30 may transmit the flight start point and the target point information to the unmanned airplane 10 through the server 20 or may transmit the starting point and the target point information directly to the unmanned airplane.

The unmanned airplane 10 that receives the flight start point and the target point information receives the map data or the modeling data including the starting point and the target point from the server 20 and directly performs the flight path search, Lt; / RTI >

Alternatively, the flight path searched by the user terminal 30 can be received directly or through the server 20 by the UAV 10.

That is, the flight path search of the UAV 10 may be performed by at least one of the UAV 10, the server 20, or the user terminal 30. [ Specifically, the unmanned air vehicle 10, the server 20, or the user terminal 30 will need to include a processor such as an MCU, MPU, CPU, DSP capable of executing a software program for searching for a flight path.

FIG. 3 shows a flowchart of a method of searching a flight path of the UAV 10 according to a preferred embodiment of the present invention.

3, the method for searching a flight path of the UAV 10 according to one preferred embodiment of the present invention is a method for searching for a flight path of the UAV 10 by inputting map data or modeling data including a starting point and a target point of the UAV 10 Dividing the map data or the modeling data in step S10 into a plurality of cells of the same size on the top view (step S20), searching for a primary path arriving at the target point via the plurality of cells from the starting point S30), and searching for a secondary path arriving at a target point via a plurality of cells from a starting point using the primary path searched in step S30 (S40).

In step S30, an Aceh algorithm can be used. The AceTa algorithm is the most commonly used pathfinding algorithm in general.

4 shows an example of a primary path search result obtained by the AceT algorithm.

As can be seen from FIG. 4, when there is an obstacle between the starting point and the target point according to the results of the first-order path search, only a path bent at an angle of 45 degrees is searched and it is difficult to search the shortest path.

Therefore, the present invention is characterized in that the primary path searched in step S30 is supplemented by step S40.

5 shows a flowchart of step S40.

As can be seen from FIG. 5, in step S40, if there are cells in the path where the path is broken, among the plurality of cells passing through the starting point cell, the target point cell, and the primary path, S41) and generating a set S having two numbers as a combination of the elements using the cells numbered in the step S41 (S42). However, in step S42, the combination of the cell number of the starting point and the cell number of the target point is preferably excluded.

In step S40, it is determined whether or not the set S is an empty set. In step S43, if the set S is not an empty set, elements having the largest difference between the two numbers are selected. (S44) of selecting the element having the smallest minimum value among the two numbers when there are a plurality of elements having the largest difference between the numbers, and searching a straight line between the two numbers included in the selected element in the step S44 S45) and determining whether or not an obstacle exists in the straight path detected in step S45 (step S46).

If it is determined in step S40 that there is an obstacle, step S47 may include removing the selected element from the set S in step S44. However, after step S47 is completed, step S43 may be performed. .

Preferably, if it is determined in step S40 that there is no obstacle, step S40 is to delete the first path between two numbers included in the selected element in step S44, and to delete the second path included in the selected element in step S44 (Step S48) of adding the new path by connecting the numbers of the new paths and removing the element from the set S if there is an element including the number included in the added new path, After completion, the process proceeds to step S47.

If it is determined in step S43 that the set S is an empty set, the path search is terminated.

FIG. 6 shows an exemplary result of applying the step S40 to the primary search path of FIG.

The application of step S40 will be described in detail with reference to FIG.

First, if there are cells in the path where the path of the starting point cell, the target point cell, and the plurality of cells passing through the primary path are bent by the step S41, if the cells are numbered in the order of the paths, , 2, 3, 4, and 5, respectively.

In addition, in step S42, the set S is generated as follows.

S = {(1,4) (1,3) (2,5) (2,4) (3,5)}

If it is determined in step S43 that the set S is an empty set, it is not an empty set. Therefore, among (1,4) and (2,5) ) Is smaller than (1, 4).

In addition, the straight path between (1, 4) selected in step S44 is searched for in step S45, and since there is an obstacle as a result of the determination in step S46, (1,4) .

Thus, the set S is as follows.

S = {(1,3) (2,5) (2,4) (3,5)}

If it is determined in step S43 that the set S is an empty set, it is not an empty set. Therefore, in step S44, the largest value (2,5) is selected. In addition, the straight path between (2,5) selected in step S45 is searched, and since an obstacle exists as a result of the determination in step S46, (2,5) is removed from the set S by step S47.

Thus, the set S is as follows.

S = {(1,3) (2,4) (3,5)}

If it is determined in step S43 that the set S is an empty set, it is determined that the difference between the numbers obtained in step S44 is the largest and the minimum value is smaller than (1,3) since the empty set is not empty. In addition, the straight line between (1,3) selected in step S44 is searched for in step S45, and since there is no obstacle as a result of the determination in step S46, it is included in the elements (1,3) selected in step S44 in step S48 (1 → 2 and 2 → 3) between the two numbers, and adds the new path by connecting the two numbers included in the elements (1,3) selected in the step S44, and adds (2, 4) containing the number 2 contained between the new paths is removed from the set (S).

In step S47, the selected element (1,3) is removed from the set (S) in step S44.

Thus, the set S is as follows.

S = {(3,5)}

If it is determined in step S43 that the set S is an empty set, it is determined that the set S is not an empty set. In addition, the straight line between (3,5) selected in step S44 is searched for in step S45, and since there is no obstacle as a result of the determination in step S46, it is included in the elements (3,5) selected in step S44 in step S48. And deletes the primary paths (3 → 4 and 4 → 5) between the two numbers. In step S47, the selected element (3, 5) is removed from the set (S) in step S44.

As a result, the set S is empty and is terminated.

Finally, the flight path is (1 → 3 → 5).

As described above, according to the flight path searching method of the UAV 10 of the present invention, it can be seen that the route searched in the existing route search algorithm such as the AceT algorithm can be optimized by a simple algorithm.

100: Unmanned aerial vehicle system
10: Unmanned aircraft
20: Server
30: User terminal

Claims (7)

A method for searching a flight path of an unmanned airplane,
(a) receiving map data or modeling data including a start point and a target point of the UAV;
(b) dividing the map data or modeling data into a plurality of cells of equal size;
(c) searching for a primary path from the starting point to the target point via a plurality of cells; And
(d) using the primary path to search for a secondary path that arrives at the target via the plurality of cells from the starting point. The method according to claim 1,
The step (d)
(d-1) if there are cells at the starting point, at the target point, and at the path where the path passes through among the plurality of cells passing through the primary path, numbering the corresponding cells in a path order; And
(d-2) using the numbered cells to generate a set with two element combinations as elements. 3. The method of claim 2,
The step (d)
(d-3) determining whether the set is an empty set;
(d-4) If the set is not an empty set as a result of the judgment in the step (d-3), the element having the largest difference between the two numbers is selected. Selecting the element having the smallest minimum value among the numbers of the elements; And
(d-5) searching for a straight-line path between two numbers included in the element selected in the step (d-4). The method of claim 3,
The step (d)
(d-6) determining whether an obstacle is present in the straight path detected in the step (d-5); And
(d-7) removing an element selected in the step (d-4) from the set when the obstacle exists as a result of the determining in the step (d-6)
Wherein the step (d-3) is performed after completion of the step (d-7). 5. The method of claim 4,
The step (d)
(d-8) if the obstacle does not exist as a result of the determination in step (d-6), deletes the primary path between two numbers included in the element selected in step (d-4) the new path is added by connecting the two numbers included in the selected element in the step (d-4), and if there is an element including the number included between the added new paths, the element is removed from the set Further comprising:
Wherein the step (d-7) is performed after completion of the step (d-8). 6. The method according to any one of claims 2 to 5,
And if the set is an empty set as a result of the determination in the step (d-3), the path search is terminated. The method according to claim 1,
The step (c)
A method for searching a flight path of an unmanned airplane,

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