KR102217208B1 - Method and apparatus for searching route - Google Patents

Abstract

A path search method performed by a path search apparatus according to an embodiment of the present invention includes the steps of: identifying a starting point and a target point among a plurality of nodes in a three-dimensional space; calculating a path cost using a cost function, to which the secondary change rate of a physical property depending on a distance or required time and the location of each node with respect to a plurality of search paths from a reference node to an extendable node via an intermediate node wherein a starting point is used as the reference node, the intermediate node is extendable from the reference node and the extendable node is extendable from the intermediate node; repeating a process of calculating the path cost until a new extendable node matches the target point using a cost function to which the secondary change rate for the physical property depending on a distance or required time and the location of each node is reflected with respect to a plurality of search paths to a new intermediate node and a new extendable node by changing the reference node based on the calculated path cost; and determining a path from the starting point to the target point based on the calculated path costs. The present invention can search a path with respect to a plurality of virtual nodes in a three-dimensional space.

Description

Route search method and device {METHOD AND APPARATUS FOR SEARCHING ROUTE}

The present invention relates to a path search method and apparatus, and more particularly, a method of searching a path from a starting point to a target point for a plurality of virtual nodes in space that can be three-dimensional path points, and performing this method. It's about a device that can do it.

A Star algorithm is a technology that searches a path from a starting point to a target point for a plurality of virtual nodes in a 3D space that can be path points. The A Star algorithm starts from the starting point for a set of nodes at a predetermined location and moves one line segment to the neighboring nodes that can proceed, and each time, the sum of the elapsed distance from the starting point to the corresponding node and the predicted distance from the node to the target point It is a technology to find a path that becomes the shortest elapsed distance from the start point to the target point by repeating the process of calculating and selecting the node with the smallest value among them.

However, the A Star algorithm has limitations in finding a path that satisfies the constraints on the rate of change in space or rate of change in time. In other words, in the A Star algorithm, the basic unit of a path in a group of nodes organized in space is a line segment that connects a node and an adjacent node, so when selecting a path, the distance from one node to another B. The physical properties constituting the cost function reflecting the elapsed time or movement or transmission speed can be considered, but the rate of change in time or space of the properties defined for each node location or location cannot be considered.

Republic of Korea Patent Publication No. 10-2094538, registration date March 23, 2020.

An embodiment of the present invention provides a path search method and apparatus for searching a path from a starting point to a target point in consideration of a second rate of change in time or space for a plurality of virtual nodes in a three-dimensional space that can be path points. .

The problem to be solved of the present invention is not limited to those mentioned above, and another problem to be solved that is not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

The route search method performed by the route search apparatus according to the first aspect includes the steps of identifying a starting point and a target point among a plurality of nodes in a three-dimensional space, and using the starting point as a reference node and passing through an intermediate node that can proceed from the reference node. Thus, calculating a route cost using a cost function reflecting a second rate of change of a property depending on a distance or a required time and a location of each node for a plurality of search routes from the intermediate node to an extended node, and the Based on the calculated route cost, a cost function reflecting the secondary change rate of the physical properties depending on the distance or time required and the location of each node for a plurality of search routes to the new intermediate node and the new expansion node by changing the reference node And repeating the process of calculating the path cost by using until the new expansion node coincides with the target point, and determining a path from the start point to the target point based on the calculated path costs. .

The route search apparatus according to the second aspect includes an information acquisition unit for acquiring 3D spatial information and information on a starting point and a target point, and a path by receiving the spatial information, the starting point and information on the target point from the information acquisition unit. And a processor unit configured to generate a plurality of virtual nodes that can be points and determine a path from the start point to the target point, and the processor unit selects an intermediate node that can proceed from the reference node using the start point as a reference node. The route cost is calculated using a cost function that reflects the secondary change rate of the physical properties depending on the distance or time required and the location of each node for a plurality of search routes from the intermediate node to the extension node that can proceed through the route, and the calculation By changing the reference node based on the established path cost, a cost function is used that reflects the secondary change rate of the physical properties depending on the distance or time required and the location of each node for a plurality of search paths to the new intermediate node and the new expansion node. Thus, the process of calculating the path cost is repeated until the new expansion node coincides with the target point, and a path from the start point to the target point is determined based on the calculated path costs.

The computer-readable recording medium storing the computer program according to the third aspect, when the computer program is executed by a processor, confirms a starting point and a target point among a plurality of nodes in a three-dimensional space, and the starting point is referenced. Cost reflecting the distance or time required for multiple search paths from the intermediate node through the intermediate node that can be processed from the reference node as a node and the secondary change rate of the physical properties depending on the location of each node Calculating a route cost using a function, and a distance or time required for a plurality of search routes to a new intermediate node and a new expansion node by changing the reference node based on the calculated route cost, and the location of each node Repeating the process of calculating the path cost using the cost function reflecting the secondary change rate of the material property dependent on the new expansion node until the target point is coincident, and the starting point based on the calculated path costs. And instructions for causing the processor to perform a method including determining a path from to the target point.

The computer program stored in the computer-readable recording medium according to the fourth aspect, when the computer program is executed by a processor, confirms a starting point and a target point among a plurality of nodes in a three-dimensional space, and the starting point is referenced. Cost reflecting the distance or time required for multiple search paths from the intermediate node through the intermediate node that can be processed from the reference node as a node and the secondary change rate of the physical properties depending on the location of each node Calculating a route cost using a function, and a distance or time required for a plurality of search routes to a new intermediate node and a new expansion node by changing the reference node based on the calculated route cost, and the location of each node Repeating the process of calculating the path cost using the cost function reflecting the secondary change rate of the material property dependent on the new expansion node until the target point is coincident, and the starting point based on the calculated path costs. And instructions for causing the processor to perform a method including determining a path from to the target point.

According to an embodiment of the present invention, a path from a starting point to a target point may be searched for a plurality of virtual nodes in a three-dimensional space in consideration of a second rate of change in time or space.

1 is a block diagram of a route search apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating a route search method performed by a route search apparatus according to an embodiment of the present invention.
FIG. 3 is a diagram showing a pair of nodes consisting of a reference node, an intermediate node, and an extension node, which are basic units constituting a path, and a pair of line fragments continuously connecting them.
FIG. 4 is a diagram showing both a pair of nodes including an intermediate node of (Case 1) and an extension node that can proceed through it for one reference node given in a two-dimensional orthogonal coordinate system, and a pair of line fragments connecting them continuously. .
FIG. 5 is a diagram showing both a pair of nodes including an intermediate node of (Case 2) and an extension node that can proceed through it for one reference node given in a two-dimensional orthogonal coordinate system, and a pair of line fragments connecting them in succession. .
FIG. 6 is a diagram showing both a pair of nodes including an intermediate node of (Case 3) and an extension node that can be progressed through it for one reference node given in a two-dimensional orthogonal coordinate system, and a pair of line fragments connecting the same. .
7 is a diagram showing all pairs of nodes that can be formed for a given reference node in a two-dimensional orthogonal coordinate system and all pairs of line fragments connecting them in succession.
8 is a pair of nodes that can be continuously connected by two line pieces around a given reference node within a spatial area D in which path points can be generated excluding obstacles in a two-dimensional orthogonal coordinate system, and a line piece pair connecting them. This is a picture that shows all of them.
9 shows the results of obtaining an optimal path for a starting point and a target point arbitrarily designated on an arbitrary terrain without considering the acceleration cost term in the cost function on a 3D topographic map.
FIG. 10 is a plot of the result of FIG. 9 on a two-dimensional contour line.
FIG. 11 shows an optimal path obtained by considering an acceleration cost term in a cost function in order to limit acceleration in the direction of gravity for a starting point and a target point arbitrarily designated on the same terrain as in FIG. 10 on a 3D topographic map.
12 shows the results of FIG. 11 on a two-dimensional contour line.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms, and only these embodiments make the disclosure of the present invention complete, and those skilled in the art to which the present invention pertains. It is provided to fully inform the person of the scope of the invention, and the scope of the invention is only defined by the claims.

In describing the embodiments of the present invention, detailed descriptions of known functions or configurations will be omitted except when actually necessary in describing the embodiments of the present invention. In addition, terms to be described later are terms defined in consideration of functions in an embodiment of the present invention, which may vary according to the intention or custom of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

1 is a block diagram of a route search apparatus according to an embodiment of the present invention.

Referring to FIG. 1, a path search apparatus 100 according to an embodiment includes an information acquisition unit 110 and a processor unit 120, and further includes a storage unit 130 and/or an output unit 140. can do.

The information acquisition unit 110 acquires 3D spatial information on an area in which a path can be generated, and location information on a starting point and a target point, and provides the obtained information to the processor unit 120. For example, the information acquisition unit 110 may include a communication module capable of receiving 3D spatial information through a communication network or an interface capable of directly receiving a 3D spatial complement.

The processor unit 120 receives spatial information, information about a starting point, and a target point from the information acquisition unit 110 to form a plurality of nodes that can be path points, and determine a path from the starting point to the target point. The processor unit 120 uses the starting point as a reference node and depends on the distance or time required and the location of each node for a plurality of search paths from the intermediate node to the expansion node that can proceed from the reference node via the intermediate node. The route cost can be calculated using a cost function that reflects the secondary rate of change of the physical properties, and the distance or required for multiple search routes to the new intermediate node and the new expansion node by changing the reference node based on the calculated route cost The process of calculating the path cost using the cost function reflecting the secondary change rate of the material properties depending on the time and location of each node can be repeated until the new expansion node matches the target point, and based on the calculated path costs Thus, the path from the starting point to the target point can be determined. Here, the secondary rate of change may be acceleration. For example, the acceleration may be an acceleration in the direction of gravity, and the turning acceleration may be limited to a specific value or less as the acceleration. A processing procedure in which the processor unit 120 determines a path from a starting point to a target point among a plurality of nodes will be described again with reference to FIG. 2.

The storage unit 130 may store a result of processing by the processor unit 120 under the control of the processor unit 120. For example, the storage unit 130 includes magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and floptical disks. It may be a computer-readable recording medium such as a hardware device specially configured to store and execute program instructions such as magneto-optical media or flash memory.

The output unit 140 may output a result of processing by the processor unit 120 under control of the processor unit 120. For example, the output unit 140 may include a communication module capable of transmitting a result of processing by the processor unit 120 or an interface capable of transmitting to another electronic device. In addition, the output unit 140 may include a display device or a printing device capable of visually identifying the result of processing by the processor unit 120.

2 is a flowchart illustrating a route search method performed by a route search apparatus according to an embodiment of the present invention.

Referring to FIG. 2, a path search method according to an embodiment includes a step S210 of confirming a starting point and a target point among a plurality of nodes in a 3D space.

In addition, the path search method uses the starting point as the reference node, and physical properties depending on the distance or required time and the location of each node for a plurality of search paths from the intermediate node to the expansion node that can be progressed through the intermediate node that can be progressed from the reference node. It further includes a step (S220) of calculating the route cost by using the cost function in which the secondary change rate is reflected.

In addition, the path search method changes the reference node based on the calculated path cost, and the second rate of change of the physical properties depending on the distance or the required time and the location of each node for a plurality of search paths to the new intermediate node and the new expansion node. A step (S230) of repeating the process of calculating the path cost by using the reflected cost function until the new expansion node coincides with the target point (S230). Here, the secondary rate of change may be an acceleration, and the acceleration in the direction of gravity may be limited or the turning acceleration may be limited to a specific value or less through the process of selecting a node pair in which the secondary rate of change term is included in the cost function and the value of the cost function is small. have.

In addition, the route search method further includes a step (S240) of determining a route from the start point to the target point based on the calculated route costs.

Looking at step S220 in more detail, information on a node pair including an intermediate node and an extension node that can be successively connected from the reference node by two line segments and information on the corresponding path cost are stored in the first list. It may include a first step.

Looking at step S230 in more detail, steps 2 to 6 may be included. In the second step, information about the node pair with the smallest cost function value among the node pairs stored in the first list and information about the corresponding path cost are stored in the second list, and the middle of the node pair stored in the second list. A node can be newly set as a reference node. In the third step, information on all node pairs that can be connected continuously by two line segments from the reference node newly set in the second step and are not stored in the second list, and information on the corresponding path cost, is the first. You can save it in the list and perform the second step again, but if the expansion node matches the target point among the newly found node pairs in the third step, the fourth step is immediately performed. Here, if the node pair information identical to the newly found node pair in the third step is already in the first list, the cost function values may be compared and replaced with a smaller value. The fourth step can be connected continuously by two line segments from the reference node newly set in step 3, and if one or more of the node pairs not stored in the second list coincide with the target point, the second Among the node pairs stored in the list, the expansion node matches the target point, and among them, the node pair with the smallest cost function value is determined and stored in the third list, and the corresponding node pair can be set as the reference node pair. The fifth step is to store the node pairs in the third list where the nodes stored as intermediate nodes and extension nodes among the node pairs stored in the second list match the reference node and the intermediate node of the reference node pair stored in the third list, respectively, and the corresponding node. Pairs can be newly set as reference node pairs. In the sixth step, the fifth step may be repeated until the reference node of the newly set reference node pair coincides with the starting point.

Looking at step S240 in more detail, a path is determined by sequentially connecting the intermediate nodes of the reference node pair stored in the third list from the start point to the target point.

Hereinafter, a route search method performed by the route search apparatus 100 according to an embodiment of the present invention will be described in more detail with reference to FIGS. 1 to 12.

First, the information acquisition unit 110 of the path search apparatus 100 acquires information about a plurality of nodes in a 3D space and information about a starting point and a target point among the plurality of nodes, and uses the obtained information to the path search apparatus 100 ) Provided to the processor unit 120.

Then, the processor unit 120 generates a plurality of nodes that can be path points based on the spatial information, the starting point and the target point provided from the information acquisition unit 110, and calculates the path from the starting point to the target point in FIG. It is decided according to the processing procedure in the flowchart.

A processing procedure in which the processor unit 120 determines a path from a starting point to a target point for a plurality of nodes in a 3D space is as follows.

A reference node is selected from among a plurality of nodes, and a node connecting two wire fragments out of a pair of nodes that can be successively connected by two wire fragments from the reference node is called an intermediate node, and the node opposite the reference node is called an extension node. .

(N은 자연수)으로 기준노드의 좌표

와 두 구간 이상 벌어지게 되며 중간노드 N_I(u) ^(l)의 좌표는 다음 조건식으로 표현될 수 있다. 여기서, D는 경로점이 될 수 있는 공간상 노드의 집합체를 의미하며, 해당 영역 안의 노드는 어떤 것이든 중간노드나 확장노드가 될 수 있다.In a two-dimensional space, if the reference node and the extension node are called N _R(u) and N _E(u) respectively in the given order (u)th, the coordinates of the extension node are

(N is a natural number) the coordinates of the reference node

And more than two intervals, and the coordinates of the intermediate node N _I(u) ^(l) can be expressed by the following conditional expression. Here, D denotes a collection of nodes in space that can be path points, and any node in the corresponding region can be an intermediate node or an extension node.

에 대하여,

이고(여기서, N은 자연수),

about,

And (where N is a natural number),

이거나

이고,

일 때, [Case 1]

Or

ego,

when,

,

(if

)

,

(if

)

,

(if

)

,

(if

)

일 때,[Case 2]

when,

,

,

일 때, [Case 3]

when,

(if

)

(if

)

으로 확장노드

와 두 구간 이상 벌어지게 되며 중간노드 N_I(u) ^(l)의 좌표는 다음 조건식으로 표현될 수 있다.In a similar way, it can also be expanded in 3D space. The coordinates of the reference node at the given order (u)th are

Extension node

And more than two intervals, and the coordinates of the intermediate node N _I(u) ^(l) can be expressed by the following conditional expression.

에 대하여,

이고(여기서, N은 자연수),

about,

And (where N is a natural number),

일 때, [Case 1]

when,

일 때,[Case 2]

when,

(if

)

(if

)

(if

)

(if

)

(if

)

(if

)

일 때, [Case 3]

when,

일 때, [Case 4]

when,

일 때, [Case 5]

when,

)까지 있을 수 있다.Up to 362 pairs of line fragments connecting adjacent extension nodes from a given reference node in a three-dimensional orthogonal or curved coordinate system (

).

FIG. 4 is a diagram showing both a pair of nodes including an intermediate node of (Case 1) and an expansion node that can proceed through it for one reference node given in a two-dimensional orthogonal coordinate system, and a pair of line fragments connecting the same. 5 is a diagram showing both a pair of nodes including an intermediate node of (Case 2) and an expansion node that can proceed through it for one reference node given in a two-dimensional orthogonal coordinate system, and a pair of line fragments connecting them in succession. 6 shows both a pair of nodes including an intermediate node of (Case 3) and an expansion node that can proceed through it for one reference node given in a two-dimensional orthogonal coordinate system, and a pair of line fragments connecting them in succession. 7 is a diagram showing all pairs of nodes that can be formed for a given reference node in a two-dimensional orthogonal coordinate system and all pairs of line fragments connecting them in succession, and FIG. 8 is a diagram excluding obstacles in a two-dimensional orthogonal coordinate system. This is a picture showing both a pair of nodes that can be connected successively by two line pieces around a given reference node within the spatial area D in which path points can be created, and a pair of line pieces connecting them.

On the other hand, the cost function in general A Star algorithm and transformation algorithm usually has the following form.

,

,

,

,

,

는 각각 출발점과 목표점을 지칭하며,

,

은 (u)번째에서의 기준노드와 확장노드를 가르킨다.

는 유클리디안 거리 혹은 기타 admissible의 특성을 갖는 다른 종류의 거리로 정의될 수 있다. *표시는 (u)번째에서 기준노드로부터 두 개의 선조각에 의해 연속적으로 연결될 수 있는 선조각 쌍 중 비용함수를 계산하기 위해 고려된 하나의 노드쌍과 이에 대응하는 계산결과를 의미한다. g는 시작점부터 기준노드까지의 총 경과거리이며, h는 기준노드로부터 목표점까지의 총 예측 경과거리이다. f는 g와 h가 더해진 형태를 가진 비용함수이다.here,

,

Denotes the starting point and the target point, respectively,

,

Indicates the base node and extension node at (u)th.

Can be defined as a Euclidean distance or any other kind of distance with other admissible characteristics. The * indicates one node pair considered for calculating the cost function among the pair of line pieces that can be successively connected by two line pieces from the reference node at the (u)th and the corresponding calculation result. g is the total elapsed distance from the start point to the reference node, and h is the total estimated elapsed distance from the reference node to the target point. f is a cost function in the form of g and h added together.

The cost function of the coarse A Star algorithm with the cost function of the second-order rate of change term over time or space is not only the term corresponding to the distance from the starting point and the target point, as shown in the following equation, but also the second order of properties depending on the node position The term a corresponding to the rate of change (eg acceleration) is additionally included.

,

,

,

,

,

,

는 각각 출발점과 목표점을 지칭하며,

,

,

는 각각 (u)번째에서 고려된 기준노드와 중간노드, 그리고 확장노드를 가르킨다. W₁과, W₂는 임의로 설정 가능한 변수이며, *표시는 (u)번째에서 기준노드로부터 두 개의 선조각에 의해 연속적으로 연결될 수 있는 선조각 쌍 중 비용함수를 계산하기 위해 고려된 하나의 노드쌍과 이에 대응하는 계산결과를 의미한다.

는 앞 서 설명된 거리와 동일하다. g는 시작점부터 기준노드까지의 총 경과거리이며, h는 기준노드로부터 목표점까지의 총 예측 경과거리이다. f는 g와 h가 더해진 형태를 가진 비용함수이다.here,

,

Denotes the starting point and the target point, respectively,

,

,

Denotes the reference node, intermediate node, and extension node considered in the (u)th, respectively. W ₁ and W ₂ are variables that can be set arbitrarily, and the * mark is one node considered to calculate the cost function among the pairs of wire segments that can be successively connected by two wire segments from the reference node at the (u) th It means the pair and the corresponding calculation result.

Is the same as the distance described earlier. g is the total elapsed distance from the start point to the reference node, and h is the total estimated elapsed distance from the reference node to the target point. f is a cost function in the form of g and h added together.

Meanwhile, the processor unit 120 of the path search apparatus 100 uses an acceleration cost term applicable to a problem of finding an optimal path in a three-dimensional space in which coordinates of one axis are determined by coordinates on two other axes. That is, when the z-direction flight altitude is constrained by the topographic altitude H(x, y) in the area where the path can be formed and the flight altitude apart from the ground that can be set arbitrarily, the z-direction path coordinate is in x, y. Depend on,

The problem of finding the best path results in determining the coordinates (x, y) on the other two axes excluding altitude. In this problem, the expression of the acceleration cost term to find the optimal path where acceleration in the direction of gravity is limited is as follows.

,

,

는

와

사이 구간을 이동/전달하는 속도의 평균치로 조건으로 주어지거나 설정 가능하며,

은

와

사이의 가속도비용항을 의미한다.here,

Is

Wow

It can be given or set as a condition as the average value of the speed of moving/transmitting between sections.

silver

Wow

Means the term of acceleration cost between.

In addition, when it is desired to limit the acceleration to be less than a specific value in calculating the cost function each time, it is possible to set various types of cost terms in which the cost increases rapidly when the value exceeds the value. In other words,

In the case of exceeding the reference acceleration a _c , the acceleration cost term in the form of conditionally charging is applicable.

The expression of the acceleration cost term that can be set to find an optimal path where acceleration in the opposite direction of gravity is limited is as follows.

,

,

Likewise, the acceleration cost term can take other forms to limit it to a specific acceleration value.

In addition, the processor unit 120 of the path search apparatus 100 may consider a problem of finding a short-distance path limiting the acceleration of the turning operation in a three-dimensional space, and the acceleration cost term applied to this problem has the following expression.

,

,

에 대한 제한 선회반경은 다음 식으로 구할 수 있으며,In order to limit the rotational acceleration, it is necessary to appropriately set the physical distance interval between the node and the node, and to limit the intermediate node and the extension node that can be selected during expansion. That is, given or settable flight speed when the limiting acceleration of the turn to be limited is a _c

The limiting turning radius for can be obtained by the following equation,

이상으로 제한하고 경로생성을 위한 확장 시 기준노드로부터 거리가

를 초과하는 노드만 확장노드의 대상으로 고려하여 최소비용 경로점 탐색 알고리즘을 적용한다. 여기서

는 임의로 설정 가능한 값이다.By applying an equally spaced Cartesian coordinate system in 3D space,

The distance from the reference node is limited to the above and extended for path creation.

The least cost path point search algorithm is applied by considering only the nodes exceeding the value as the target of the extension node. here

Is a value that can be set arbitrarily.

The processor unit 120 of the path search apparatus 100 may perform a series of processes represented by the following first to seventh steps in order to find an optimal path of least cost connecting the target point from the start point.

<Step 1>

The starting point is set as a reference node, and a set of node pairs that can be connected successively by two line segments from the reference node is classified by node pair and stored in the <<OPEN>> list as the first list. At this time, the form of the result stored in the list is (reference node, intermediate node, extension node, h function value, g function value, f function value).

<Step 2>

Among the results stored in the <<OPEN>> list, one result with the smallest f-value is stored as a second list in the <<CLOSED>> list, and the intermediate node of the corresponding result is newly set as the reference node.

<Step 3>

In the second step, the function value is newly calculated by searching for all pairs of nodes that can be connected continuously by two line segments from the newly set reference node and not stored in 《CLOSED》 (reference node, intermediate node, extension node, h function The value, g function value, f function value) are stored in the <<OPEN>> list, and the second step is performed again. If one or more of the newly found node pairs are already in the 《OPEN》 list, the value of the f function is compared and replaced with a smaller cost function value. However, if one or more of the node pairs not stored in 《CLOSED》 coincide with the target point, which can be connected in succession by two line segments from the reference node, the second step does not go to step Go ahead.

<Step 4>

Among the results stored in the 《CLOSED》 list, the expansion node matches the target point and identifies one node pair with the smallest f function value among them, and is in the form of (reference node, intermediate node, expansion node) 《optimal path node pair collection》 And set the corresponding node pair as the reference node pair.

<Step 5>

Among the results in the 《CLOSED》 list, the nodes stored as intermediate nodes and extension nodes are searched for node pairs that match the reference node and intermediate node of the reference node pair in the 《optimum path node pair collection》 respectively, and this is used as a third list. Stored in the pair vowels>> and newly set the corresponding node pair as the reference node pair.

<Step 6>

The process of step 5 is repeated until the reference node of the reference node pair coincides with the starting point.

<Step 7>

From the start point to the target point, the optimal path is obtained by connecting the intermediate nodes of the reference node pair stored in the 《optimal path node pair collection》 in order.

Thereafter, the processor unit 120 of the path search device 100 is the result of the processing by the processor unit 120 under the control of the processor unit 120, that is, information on the optimal path of the least cost connecting the target point from the start point. Can be saved. In addition, the output unit 140 of the path search device 100 is the result of the processing by the processor unit 120 under the control of the processor unit 120, that is, information on the optimal path of the least cost connecting the target point from the start point. Can be printed.

9 shows the results of obtaining an optimal path for a starting point and a target point arbitrarily designated on an arbitrary terrain without considering the acceleration cost term in the cost function, and FIG. 10 shows the result of FIG. 9 on a two-dimensional contour line. It was drawn above.

FIG. 11 is a 3D topographical map showing an optimal path obtained by considering an acceleration cost term in a cost function in order to limit acceleration in the direction of gravity for a starting point and a target point arbitrarily designated on the same terrain as in FIG. 10, and FIG. The result of 11 is plotted on a two-dimensional contour line.

As described so far, according to the embodiment of the present invention, a path from a start point to a target point can be searched for a plurality of nodes in a three-dimensional space in consideration of a second rate of change in time or space.

Combinations of each block of the block diagram attached to the present invention and each step of the flowchart may be performed by computer program instructions. Since these computer program instructions can be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, the instructions executed by the processor of the computer or other programmable data processing equipment are shown in each block or flow chart of the block diagram. Each step creates a means to perform the functions described. These computer program instructions can also be stored on a computer-usable or computer-readable recording medium that can be directed to a computer or other programmable data processing equipment to implement a function in a specific manner, so that the computer-readable or computer-readable medium. It is also possible to produce an article of manufacture in which the instructions stored on the recording medium contain instruction means for performing the functions described in each block of the block diagram or each step of the flowchart. Computer program instructions can also be mounted on a computer or other programmable data processing equipment, so that a series of operating steps are performed on a computer or other programmable data processing equipment to create a computer-executable process to create a computer or other programmable data processing equipment. It is also possible for the instructions to perform the processing equipment to provide steps for performing the functions described in each block of the block diagram and each step of the flowchart.

In addition, each block or each step may represent a module, segment, or part of code comprising one or more executable instructions for executing the specified logical function(s). In addition, it should be noted that in some alternative embodiments, functions mentioned in blocks or steps may occur out of order. For example, two blocks or steps shown in succession may in fact be performed substantially simultaneously, or the blocks or steps may sometimes be performed in the reverse order depending on the corresponding function.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains will be able to make various modifications and variations without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain the technical idea, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: route search device
110: information acquisition unit
120: processor unit
130: storage unit
140: output

Claims (14)

delete delete As a route search method performed by a route search device,
Checking a starting point and a target point among a plurality of nodes in 3D space, and
Using the starting point as a reference node, a second difference in physical properties depending on the distance or time required and the location of each node for a plurality of search paths from the intermediate node to the expansion node that can proceed from the reference node through the intermediate node that can proceed from the reference node Calculating route cost using the cost function reflecting the rate of change,
A cost function that reflects the distance or time required for a plurality of search paths to the new intermediate node and the new expansion node by changing the reference node based on the calculated path cost, and the secondary change rate of the physical properties depending on the location of each node Repeating the process of calculating the path cost by using until the new expansion node coincides with the target point,
Including the step of determining a route from the starting point to the target point based on the calculated route costs,
The secondary rate of change is the acceleration in the direction of gravity
Route navigation method. As a route search method performed by a route search device,
Checking a starting point and a target point among a plurality of nodes in 3D space, and
Using the starting point as a reference node, a second difference in physical properties depending on the distance or time required and the location of each node for a plurality of search paths from the intermediate node to the expansion node that can proceed from the reference node through the intermediate node that can proceed from the reference node Calculating route cost using the cost function reflecting the rate of change,
A cost function that reflects the distance or time required for a plurality of search paths to the new intermediate node and the new expansion node by changing the reference node based on the calculated path cost, and the secondary change rate of the physical properties depending on the location of each node Repeating the process of calculating the path cost by using until the new expansion node coincides with the target point,
Including the step of determining a route from the starting point to the target point based on the calculated route costs,
The cost function is that the turning acceleration is limited to a certain value or less.
Route navigation method. The method according to claim 3 or 4,
The calculating step,
A first step of storing information on a pair of nodes including the intermediate node and the expansion node that can be successively connected by two line segments from the reference node and information on the path cost corresponding to the first list Including,
The repeating step,
Among the node pairs stored in the first list, information on the node pair having the smallest cost function and information on the path cost corresponding to the node pair is stored in a second list, and the middle of the node pair stored in the second list A second step of newly setting a node as the reference node,
From the reference node newly set in the second step, information on all node pairs that can be continuously connected by two line segments and not stored in the second list and information on the path cost corresponding to the first A third step of performing the second step again when there is no node pair in which the expansion node coincides with the target point among node pairs that can be stored and stored in a list;
In the third step, if one or more of the node pairs not stored in the second list and one or more of the node pairs that can be connected continuously from the newly set reference node by two line segments coincide with the target point, the second The fourth step of determining the node pair with the smallest value of the cost function among the node pairs stored in the list and the expansion node coinciding with the target point, storing it in the third list, and setting the corresponding node pair as the reference node pair. ,
Among the node pairs stored in the second list, nodes stored as an intermediate node and an extension node are stored in the third list, and a node pair corresponding to the reference node and the intermediate node of the reference node pair stored in the third list, respectively, and the corresponding node pair. The fifth step of newly setting is a reference node pair, and
A sixth step of repeating the fifth step until the reference nodes of the newly set reference node pair coincide with the starting point,
The determining step,
And a seventh step of determining the path by sequentially connecting intermediate nodes of the reference node pair stored in the third list from the start point to the target point.
Route navigation method. The method of claim 5,
If the same node pair information as the newly found node pair in the third step is already in the first list, the value of the cost function corresponding to the newly found node pair and the cost function corresponding to the same node pair stored in the first list. Comparing values and replacing them with smaller values
Route navigation method. delete delete An information acquisition unit that acquires 3D spatial information on an area in which a path can be generated, and information on a starting point and a target point;
A processor unit configured to form a plurality of nodes that can be route points by receiving information on the spatial information, the starting point, and the target point from the information obtaining unit and determining a path from the starting point to the target point among the plurality of nodes. and,
The processor unit,
Using the starting point as a reference node, a second difference in physical properties depending on the distance or time required and the location of each node for a plurality of search paths from the intermediate node to the expansion node that can proceed from the reference node through the intermediate node that can proceed from the reference node Route cost is calculated using the cost function reflecting the rate of change,
A cost function that reflects the distance or time required for a plurality of search paths to the new intermediate node and the new expansion node by changing the reference node based on the calculated path cost, and the secondary change rate of the physical properties depending on the location of each node Repeat the process of calculating the path cost by using until the new expansion node coincides with the target point,
Determine a route from the start point to the target point based on the calculated route costs,
The secondary rate of change is the acceleration in the direction of gravity
Route navigation device. An information acquisition unit that acquires 3D spatial information on an area in which a path can be generated, and information on a starting point and a target point;
A processor unit configured to form a plurality of nodes that can be route points by receiving information on the spatial information, the starting point, and the target point from the information obtaining unit and determining a path from the starting point to the target point among the plurality of nodes. and,
The processor unit,
Using the starting point as a reference node, the distance or time required for a plurality of search paths from the intermediate node to the expansion node that can proceed from the reference node through the intermediate node that can proceed from the reference node, and the difference in physical properties depending on the location of each node Route cost is calculated using the cost function reflecting the rate of change,
A cost function that reflects the distance or time required for a plurality of search paths to the new intermediate node and the new expansion node by changing the reference node based on the calculated path cost, and the secondary change rate of the physical properties depending on the location of each node Repeat the process of calculating the path cost by using until the new expansion node coincides with the target point,
Determine a route from the starting point to the target point based on the calculated route costs,
The cost function is that the turning acceleration is limited to a certain value or less.
Route navigation device. The method of claim 9 or 10,
The processor unit,
A first step of storing information on a node pair including the intermediate node and the expansion node, which can be successively connected from the reference node by two line segments, and information on the path cost corresponding to the first list; and ,
In the first step, information on the node pair having the smallest value of the cost function among the node pairs stored in the first list and information on the path cost corresponding to the node pair is stored in a second list, and stored in the second list. A second step of newly setting an intermediate node of a pair of nodes as the reference node,
From the reference node newly set in the second step, information on all node pairs that can be continuously connected by two line segments and not stored in the second list and information on the path cost corresponding to the first A third step of performing the second step again when there is no node pair in which the expansion node coincides with the target point among node pairs that can be stored and stored in a list;
In the third step, if one or more of the node pairs not stored in the second list and one or more of the node pairs that can be connected continuously from the newly set reference node by two line segments coincide with the target point, the second The fourth step of determining the node pair with the smallest value of the cost function among the node pairs stored in the list and the expansion node coinciding with the target point, storing it in the third list, and setting the corresponding node pair as the reference node pair. ,
Among the node pairs stored in the second list, nodes stored as an intermediate node and an extension node are stored in the third list, and a node pair corresponding to the reference node and the intermediate node of the reference node pair stored in the third list, respectively, and the corresponding node pair. The fifth step of newly setting is a reference node pair, and
A sixth step of repeating the fifth step until the reference nodes of the newly set reference node pair coincide with the starting point,
Processing a seventh step of determining the path by sequentially connecting intermediate nodes of the reference node pair stored in the third list from the start point to the target point.
Route navigation device. The method of claim 11,
The processor unit,
If the same node pair information as the newly found node pair in the third step is already in the first list, the value of the cost function corresponding to the newly found node pair and the cost function corresponding to the same node pair stored in the first list. Comparing values and replacing them with smaller values
Route navigation device. As a computer-readable recording medium storing a computer program,
The computer program, when executed by a processor,
Checking a start point and a target point among a plurality of nodes in a three-dimensional space, and using the start point as a reference node, a plurality of search paths from the intermediate node to an extension node that can be progressed through the intermediate node that can proceed from the reference node are used. For each node, calculating the route cost using a cost function reflecting the secondary change rate of the physical properties depending on the distance or time required and the location of each node, and changing the reference node based on the calculated route cost to create a new intermediate node. And a process of calculating the route cost by using a cost function reflecting the secondary change rate of the physical properties depending on the distance or time required and the location of each node for a plurality of search routes to the new extension node. And determining a path from the starting point to the target point based on the calculated path costs, wherein the second rate of change is an acceleration in the direction of gravity. A computer-readable recording medium containing instructions for performing. As a computer program stored in a computer-readable recording medium,
The computer program, when executed by a processor,
Checking a start point and a target point among a plurality of nodes in a three-dimensional space, and using the start point as a reference node, a plurality of search paths from the intermediate node to an extension node that can be progressed through the intermediate node that can proceed from the reference node are used. For each node, calculating the route cost using a cost function reflecting the secondary change rate of the physical properties depending on the distance or time required and the location of each node, and changing the reference node based on the calculated route cost to create a new intermediate node. And a process of calculating the route cost by using a cost function reflecting the secondary change rate of the physical properties depending on the distance or time required and the location of each node for a plurality of search routes to the new extension node. And determining a path from the starting point to the target point based on the calculated path costs, and the cost function is a method in which the turning acceleration is limited to a specific value or less. A computer program comprising instructions for causing the processor to perform.

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