KR100990446B1 - Method and apparatus of selecting the shortest path using normal equation division method - Google Patents

Abstract

The present invention relates to a method and apparatus for selecting a shortest route using a normal segmentation method, the method comprising selecting a shortest route among a plurality of routes between a departure point and a destination, and setting a reference route between the departure point and the destination and setting the reference route. Determining at least one normal reference point in the phase; Setting a normal passing through the determined normal reference point; Selecting at least one main path having at least a distance from the normal reference point to a point crossing the normal from among at least two or more paths intersecting the set normal; And a shortest path selection method using a normal segmentation method comprising determining a required node in the selected main path and selecting a shortest path.

Select normals, normal base points, required nodes, and shortest paths

Description

Method and apparatus for selecting the shortest path using the normal segmentation method {METHOD AND APPARATUS OF SELECTING THE SHORTEST PATH USING NORMAL EQUATION DIVISION METHOD}

The present invention relates to a method and apparatus for selecting a shortest path using a normal segmentation method, and more particularly, sets a virtual reference path between a starting point and a destination, determines at least one normal reference point on the set reference path, The path that minimizes the distance between the intersection point of the normal line and two or more paths and the normal reference point is selected as the main path, and the required nodes located at both ends of the main path are determined to determine the required node as the passing point. A method and apparatus for selecting a path are provided.

In recent years, the vehicle navigation industry has also been greatly developed due to the rapid development of the automobile industry and the activation of leisure life. The navigation guides the optimal route to reach the destination that is unknown to the driver in the shortest time, and due to its utility, it is used in many automobiles.

However, the path selection method embedded in the navigation method is based on Dijkstra algorithm, Floyd algorithm, etc., which is known as a representative path setting algorithm known through long research papers, and Bhandari algorithm, Suurballe algorithm, etc. are modified from the basic algorithm. This has been used. These existing algorithms always set the path to nodes that do not deviate much from the target direction, and the selection factors of the path setting target nodes are very simple and do not properly reflect the exception of the actual road structure. In addition, in atypical road structures, the solution often results in very different results from the actual operating situation. Here, the atypical road structure refers to a case where an obstacle such as a large river or a mountain is interposed between a starting point and a destination, or a rural road or an old road structure that is not maintained in a parcel, rather than a checkered road. As a result, the actual navigation is limited to the shortcomings such as the supplementation of the road information rather than solving the shortcomings by the route setting algorithm, and post-processing after the user's report or operation problem is found.

In addition, although the computing power has been greatly improved due to the development of hardware in recent years, the routing has been quickly made. However, the limitation of the computational resources is still significantly exposed. In other words, even in a ragged road structure, if sufficient computational resources and time are allowed, the route can be obtained for more nodes than now, and much better results can be obtained. In reality, however, it is most important to quickly set the path in the shortest time using limited resources. Therefore, no matter how advanced the equipment, the new algorithm for finding the shortest path in the shortest time requires the steady development.

The present invention has been made to overcome the above limitations, and in order to set an optimal route that can arrive at the shortest time from the starting point to the destination, a reference path is set between the starting point and the destination, and a normal reference point is set on the reference path. It is an object of the present invention to provide a shortest path selection method and apparatus using a normal segmentation method of determining and selecting a shortest path among a plurality of paths by using a normal line passing through a normal reference point.

In addition, the present invention is a non-standard road structure that is not a typical general road structure, for example, a large river or mountain, such as a blockage, unmaintained roads, highways, such as unmaintained nodes, or the distance between nodes is very Another object of the present invention is to provide a shortest path selection method and apparatus using a normal segmentation method that can solve a problem occurring in an existing path setting algorithm when searching a large case or a bypass road.

In addition, the present invention by selecting a path that is the minimum of the distance of the point of intersection with the normal from the normal reference point of the plurality of paths, compared to the existing path selection method in the same road information and the same computing equipment environment more quickly in a faster time Another object of the present invention is to provide a method and an apparatus for selecting a shortest path using a normal segmentation method capable of selecting.

In order to achieve the above object, according to an aspect of the present invention, in the method for selecting the shortest route among a plurality of routes between the starting point and the destination, the reference route between the starting point and the destination is set and the set criteria Determining at least one normal reference point on a path, setting a normal that passes through the determined normal reference point, and a distance from the normal reference point to the point of intersection with the normal among at least two or more paths that intersect the set normal A method of selecting a shortest path using a normal segmentation method may include selecting at least one or more main paths which are the minimum, and selecting a shortest path by determining an essential node from the selected main path.

Here, the reference route may be configured as a virtual straight route connecting the starting point and the destination.

The setting of the reference path between the starting point and the destination and determining at least one normal reference point on the set reference path may include determining x and y coordinates of the starting point and the destination when only one normal point is determined. When the midpoint is determined as a normal reference point, and when two or more normal points are determined, at least one specific point including the midpoint of the starting point and the destination may be determined as the normal reference point.

The setting of the normal line passing through the determined normal reference point may include setting a normal line perpendicular to the reference path at the midpoint when the normal reference point is one of the starting and destination points, and setting the normal reference point. In the case of 2 or more, after setting a normal crossing perpendicular to the reference path at the midpoint of the starting point and the destination, setting at least one normal crossing perpendicular to the reference path at a specific point other than the midpoint on the reference path. Can be configured.

The selecting of at least one main path having a minimum distance from the normal reference point to a point crossing the normal from among at least two or more paths intersecting the set normal may include determining an intersection point of the path and the normal. The method may further include calculating a distance between the determined intersection point and a normal reference point on the reference path, and selecting a path having a minimum calculated distance among the at least two paths as a main path.

The determining of the essential node in the selected main path and selecting the shortest path may include: determining a required node located at both ends of the selected main path, setting the determined required node as a passing point; and And selecting the shortest path through the waypoint.

According to another aspect of the present invention, in the apparatus for selecting the shortest route among a plurality of routes between the starting point and the destination, setting a reference route between the starting point and the destination, and determines at least one normal reference point on the set reference route And setting a normal passing through the determined normal reference point, selecting at least one main path having a minimum distance from the normal reference point to a point crossing the normal from among at least two or more paths intersecting the set normal, The shortest path selection device may be provided by determining a required node in the selected main path and using a normal division method for selecting the shortest path.

According to the present invention, in order to set an optimal route that can arrive at the shortest time from the starting point to the destination, a reference path is set between the starting point and the destination, a normal point is determined on the reference path, and a normal line passing through the normal reference point is used. By providing a shortest path selection method and apparatus using a normal segmentation method to select the shortest path from a plurality of paths.

In addition, according to the present invention, an unusual atypical road structure that is not a typical general road structure, for example, a distance between nodes or a node having a continuity characteristic such as a road or a highway that is blocked or maintained by a large river or mountain, etc. When the path is very large or the search for the bypass road, it is possible to provide a shortest path selection method and apparatus using a normal segmentation method that can solve problems such as the occurrence of errors in the path selection that occurs in the existing path setting algorithm.

In addition, according to the present invention, by selecting a path that is the minimum of the distance of the intersection point from the normal reference point from a plurality of paths, compared to the existing path selection method in the same road information and the same computing equipment environment in a faster time It is possible to provide a shortest path selection method and apparatus using a normal segmentation method capable of selecting an accurate path.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a flowchart illustrating a procedure of a method for selecting a shortest path using a normal segmentation method according to the present invention.

Referring to FIG. 1, a method of selecting a shortest path among a plurality of paths between a starting point and a destination by using a normal segmentation method first sets a reference path between a starting point and a destination and determines at least one normal reference point on the set reference path. (S101).

In step 101, the reference route refers to a virtual straight route connecting the starting point and the destination. Such a reference path may be represented by a straight line equation with coordinates of a starting point and a destination. The equation of the straight line of the reference path is as follows.

Where Xs and Ys are the x and y coordinates of the starting point Sp and Xd and Yd are the x and y coordinates of the destination Dp.

On the other hand, the normal reference point is a specific point on the reference path, which is a reference point for setting the normal. This normal reference point may first be determined by the midpoint of the x, y coordinates of the origin and destination. In addition, a specific point other than the midpoint of the starting point and the destination may be set as the normal reference point.

In other words, when the starting point and the destination are near, the shortest path can be selected only by the normal baseline corresponding to the center of the starting point and the destination, and in this case, the shortest path using only one normal reference point corresponding to the center of the starting point and the destination. However, in the case of complex and quite long distances, as in the case of actual road structures, it is more efficient to select the shortest path accurately by determining two or more normal reference points and setting two or more normals.

As a method of determining two or more normal reference points, it would be reasonable to first determine the point of origin and destination as normal reference points and further determine the normal reference points. The additional normal reference point is a specific point other than the midpoint existing on the reference path, between the origin and the midpoint, between the destination and the midpoint, the origin / destination, the opposite of the origin relative to the origin, or the origin relative to the origin. If it is on an equi-reference path, it can be determined anywhere as the normal reference point. On the other hand, if a large number of these normal reference points are determined, more accurate path selection is possible.

Then, a normal line passing through the normal reference point determined in step 101 is set (S103). Here, since the normal is a normal to an equation of a straight line of the reference path between the starting point and the destination, it can be expressed as follows by using the equation of the straight line of the reference path and the midpoint coordinates that are normal reference points.

Here, Xh and Yh are the x and y coordinates of the midpoint Hp.

On the other hand, as described above, when the normal reference point is determined by only one midpoint of the starting point and the destination, a normal line perpendicular to the reference path may be set at the midpoint, and when the normal reference point is 2 or more including the midpoint, first, the normal at the midpoint And at least one normal at a specific point located on a reference path other than the midpoint. This setting of two or more normals is to more accurately select the shortest path among the plurality of paths as described above.

Then, at least one main path having a minimum distance from the normal reference point to the point crossing the normal from among at least two or more paths intersecting with the normal set in step 103 is selected (S105). Details of step 105 will be described later with reference to FIG. 2.

In step 105, after selecting the main path, the required node is determined in the main path to select the shortest path (S107). A detailed description of step 107 will also be provided later with reference to FIG. 3.

FIG. 2 is a diagram for describing step 105 described in FIG. 1 in detail.

Referring to FIG. 2, step 105 determines coordinates of an intersection point between two or more paths and a normal line (S1051). Here, since the method of obtaining the intersection point is a well-known technique, detailed description thereof will be omitted. In step 1051, after calculating the intersection point between the normal line and two or more paths, the distance between the normal reference point and the intersection point for two or more paths can be obtained using the following equation (S1053).

Here, Xh and Yh are coordinates when the normal reference point is the midpoint of the starting point and the destination, and Xc and Yc represent the intersection point of the path and the normal.

Then, after the distance between the normal reference point and the intersection point is calculated for two or more paths, the path having the minimum distance can be selected as the main path (S1055). In this way, since the intersection between the normal reference point and the distance is closer to the reference path, the shortest path can be selected by reflecting road information on a path close to a straight line.

3 is a view for explaining step 107 described in FIG. 1 in detail.

Referring to FIG. 3, step 107 determines essential nodes in the selected main path (S1071). Here, an essential node refers to two nodes located at both ends of the main path, and means a node that must pass through the shortest path from the starting point to the destination. Then, the required node may be set as a route point (S1073), and the shortest path may be selected using an existing shortest path selection algorithm to select a path via the required node (S1075).

FIG. 4 is a diagram for describing a shortest path selection method using the normal division method described in FIG. 1.

Referring to FIG. 4, a plurality of paths exist between the source Sp (Xs, Ys) and the destination Dp (Xd, Yd), Xs and Ys are the x and y coordinates of the source Sp, and Xd and Yd are the destination Dp. x and y coordinates. Meanwhile, a straight reference path is set between the starting point and the destination, and the midpoint of the starting point and the destination existing on the reference path may be determined as the normal reference point Hp (Xh, Yh).

Once the normal reference point Hp (Xh, Yh) is determined, it is possible to set a normal Yn passing through the normal reference point Hp (Xh, Yh) and perpendicularly intersecting the reference path. Then, the coordinates of Cp, C2 to C5, which are intersection points of normal Yn and two or more paths, are calculated.

On the other hand, the distance between the normal reference point Hp (Xh, Yh) and the two points of the intersection points Cp, C2 to C5 is calculated by the above-described formula, and the path having the minimum calculated distance is selected as the main path. Since Cp (Xp, Yp) has a minimum distance from the normal reference point Hp (Xh, Yh), the path of nodes N6 and N11 can be selected as the main path.

On the other hand, the mandatory nodes are nodes located at both ends of the selected main path, and in FIG. 4, N6 and N11 nodes become mandatory nodes. Once the mandatory node is determined in this way, the mandatory node can be set as a pass-through point and subsequently run through existing path selection algorithms to select the shortest path. N6, N11 and the destination Dp route will be selected.

FIG. 5 is a diagram for describing a method of selecting a shortest path using the method described in FIG. 1 when a starting point and a destination are far.

Referring to FIG. 5, in FIG. 5, the accuracy of the shortest path selection may be increased by setting two or more normals to select the shortest path more accurately than in the case of FIG. 4. Determine the normal reference point Hp (Xh, Yh), which is the midpoint of the starting point Sp (Xs, Ys) and the destination Dp (Xd, Yd). If you set the normal Yh at the normal reference point Hp (Xh, Yh) and select the case where the distance to each path is minimum, the N13 and N17 paths and the N14 and N18 paths are selected, and these two paths will be the shortest paths. The probability is very high.

Next, it is necessary to determine a specific point other than the normal reference point Hp (Xh, Yh) as the normal reference point. In FIG. 5, Qp (Xq, which is the center point of the starting point Sp (Xs, Ys) and the center point Hp (Xh, Yh) Yq) and Rp (Xr, Yr), the midpoint of destination Dp (Xd, Yd) and midpoint Hp (Xh, Yh), are determined as normal reference points, and at these two points Qp (Xq, Yq) and Rp (Xr, Yr) Set the normals Ysh and Ydh as described above. Similarly, if you calculate the intersection of two normals and each path, and select a path with a minimum distance between the two normal reference points Qp (Xq, Yq) and Rp (Xr, Yr) and the intersection point, the normal reference point Qp (Xq, Yq) The minimum path is the starting point Sp and the N9 path, and at the normal reference point Rp (Xr, Yr), the minimum path is the difference between the two paths of the N21 and N24 paths and the N20 and N25 paths.

Therefore, since the shortest path is determined by selecting a path having a minimum distance from the normal reference point to the intersection of the three normals and each path, in FIG. 5, the required nodes are determined to be N9, N13, N17, N21, and N24. The paths of N13, N17, N21, N24 and the destination Dp will be selected as the shortest paths.

FIG. 6 is a diagram for describing a method of selecting a shortest path using the method described in FIG. 1 when there is an atypical road structure such as a mountain between a starting point and a destination.

Referring to FIG. 6, unlike FIG. 4 to FIG. 5, there is a large mountain between a starting point and a destination, and tunnels N6 to N17 exist. In the method described above, the normal reference point Hp (Xh, Yh), which is the center point of the starting point and the destination, is determined, and the normal line is calculated to calculate the distance to the intersection point. In this case, the path connected to node N6 is the only Cs2, so if the starting point Sp (Xs, Ys) is determined as the normal reference point and additionally set the normal Ys, Cs2 will be found. When the distance between the starting point Sp (Xs, Ys) is calculated by determining the intersection point of the normal and the path at the starting point Sp (Xs, Ys), the path Cs2 is selected as the main path. Therefore, the mandatory node may be determined as N2, N6, N17, and the mandatory node is determined as N1, N2, N6, N17 because it must pass via node N1 to pass through the mandatory node N2.

Similarly, after determining a specific point between the destination Dp (Xd, Yd) and the required node N17 as the normal reference point for the node N17, setting the normal Ye, and obtaining the distance to the intersection with each path, the path Ce1 is the main path. Is selected. Therefore, the node N18 may also be determined to be an essential node because the node N17 must pass through the node N18 to pass the path Ce1.

That is, in the case of FIG. 6, the required nodes are determined as N1, N2, N6, N17, and N18, and the paths arriving through the required nodes to the destination are as the starting point Sp, N1, N2, N6, N17, N18, and the destination Dp. It can be chosen as the shortest path with the required travel distance of 16Km. For reference, the distance of the route of the other route departure point Sp, N4, N8, N9, N12, N13 and the destination Dp is 20 km, and the route of the other route departure Sp, N7, N10, N15, N14 and the destination Dp is 19 km.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments. It will be apparent to those skilled in the art that variations, modifications, and improvements can be made.

1 is a flowchart illustrating a procedure of a method for selecting a shortest path using a normal segmentation method according to the present invention;

2 is a view for explaining step 105 described in FIG. 1 in detail;

3 is a view for explaining step 107 described in FIG. 1 in detail.

FIG. 4 is a diagram for describing a shortest path selection method using the normal division method described in FIG. 1.

FIG. 5 is a diagram for describing a method of selecting a shortest path using the method described in FIG. 1 when a starting point and a destination are far;

FIG. 6 is a diagram for describing a method of selecting a shortest path using the method described in FIG. 1 when there is an atypical road structure such as a mountain between a starting point and a destination.

Claims (7)

In the method of selecting the shortest route among a plurality of routes between the origin and destination, Setting a reference path between the starting point and the destination and determining at least one normal reference point on the set reference path; Setting a normal passing through the determined normal reference point; Selecting at least one main path having at least a distance from the normal reference point to a point crossing the normal from among at least two or more paths intersecting the set normal; And Determining a required node in the selected main path and selecting a shortest path Shortest path selection method using a normal segmentation method comprising a. The method of claim 1, And the reference path is a virtual straight path connecting the starting point and the destination. The method of claim 1, The step of setting a reference path between the starting point and the destination and determining at least one normal reference point on the set reference path, In the case of determining only one normal reference point, a midpoint of the x and y coordinates of the starting point and the destination is determined as the normal reference point, and when determining two or more normal points, the at least one including the midpoint of the starting point and the destination. A shortest path selection method using the normal division method, characterized in that a specific point other than the midpoint is determined as a normal reference point. The method of claim 1, Setting the normal passing through the determined normal reference point, If the normal reference point is one of the midpoints of the starting point and the destination, a normal line perpendicular to the reference path is set at the midpoint, and if the normal reference point is 2 or more, the normal point of the starting point and the destination is set to the reference path. And setting at least one normal perpendicular to the reference path at a specific point other than the midpoint on the reference path after setting the normal crossing the normal to the normal path. The method of claim 1, Selecting at least one main path having a minimum distance from the normal reference point to a point crossing the normal from among at least two paths intersecting the set normal, Determining an intersection of the path and the normal; Calculating a distance between the determined intersection point and a normal reference point on the reference path; And Selecting a path having a minimum calculated distance among the at least two paths as a main path; The shortest path selection method using a normal segmentation method comprising a. The method of claim 1, Selecting the shortest path by determining the required node in the selected main path, Determining an essential node located at both ends of the selected main path; Setting the determined required node as a waypoint; And Selecting the shortest route by way of the waypoint The shortest path selection method using a normal segmentation method comprising a. delete

Images