JPH02224200A - Device for determining route - Google Patents

Abstract

PURPOSE:To execute rapid processing by continuing links on the same road between a node existing on the same road and the node of a target point when the node existing on the same load including the node of the target point is searched on the searching process of a candidate route, and after ending the search in the process, forming a candidate route. CONSTITUTION:A steering device 1 to be mounted on a vehicle is constituted of a vehicle speed sensor 3, an azimuth sensor 4, a storage device 5 for storing road map data, and a display device 6 for displaying a current position on a road map arranged around a CPU 2 to be a main device for executing current point estimating operation or map matching operation. When a node existing on the same load including the node of the target point is searched in the case of determining a candidate route, links on the same road between the searched node and the node of the target point are continued, and after ending the search in the process, the candidate route is formed and the search of nodes existing in the interval between the searched node and the node of the target point is omitted. Consequently, the processing time can be shortened and rapid search can be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a route determining device that determines an optimal route from map information on a road where a starting point and a destination point are set.

[Background technology]

This type of route determination device uses a vehicle speed sensor and a direction sensor to estimate the current location of the vehicle from map information recorded on a storage medium, past data, etc. The system determines a route that is optimal, for example, takes the shortest time, to travel between the two locations. The map information recorded on the recording medium is assigned a number for each node such as a road intersection or a turning corner, and is segmented and recorded for each link between the nodes. There are usually multiple candidate routes between the departure point and the destination point, and after the multiple candidate routes are searched by the central processing unit, conditions such as the shortest time are selected from among the candidate routes. A satisfying route is determined.

The present invention is a further development of the above-mentioned route determining device, and aims to provide a route determining device capable of shortening the search time for candidate routes and quickly processing the route.

[Means to solve the problem]

In order to achieve the above object, the present invention sets a starting point and a destination point on a road in map information, searches for a plurality of candidate routes connecting both points, and selects the optimal route from among the searched candidate routes. A route determining device for determining a route, a medium in which the roads in the map information are segmented into nodes with identification codes and links between the nodes, and each road is recorded with an identification code; To determine a candidate route, we sequentially search for nodes that have a shorter distance from the destination node that exists on the road that intersects the starting point node, and then search for nodes on the intersecting road for each searched node. A candidate route is formed by sequentially searching for nodes with a shorter distance from the destination node existing in When a node existing above is searched for, the method further comprises a means for connecting links on the same road between nodes from that node to a destination point, and terminating the search in the process to form a candidate route. It was done.

Further, in determining the optimal route from among the searched candidate routes, the configuration includes means for determining a candidate route having a shorter total distance between a starting point and a destination point and a fewer number of turns as the optimal route. It is preferable that

Further, when determining an R & suitable route from among the searched candidate routes, if there is a prohibited section among the links constituting the candidate route during the travel time of the vehicle, the method includes means for excluding the candidate route from the candidates. Preferably, the configuration is configured.

Further, in determining the optimal route from among the searched candidate routes, it is preferable to include means for excluding the candidate route from the candidates when there is a constituent link with a width less than a predetermined width.

Further, in determining the optimal route from among the searched candidate routes, it is preferable to include means for excluding the candidate route from the candidates when there is a prohibited section depending on the vehicle type among the constituent links.

〔Example〕

The present invention will be explained based on an embodiment shown in the drawings.

Figure 1 is a circuit diagram of the onboard navigation system, Figures 2 to 4
The figure is an explanatory diagram of route determination, and FIGS. 5 and 6 are flowcharts illustrating the route determination operation by the central processing unit.

The in-vehicle navigation system 1 includes a central processing unit 2 which is the main body for current location estimation and map matching operations, a vehicle speed sensor 3, a direction sensor 4, a storage device 5 for storing road map data, and a storage device 5 that stores the current location on a road map. A display device 6 and the like for displaying images are arranged and configured. The road map data is stored in a map information storage medium 7 in the form of a CD-ROM, and is read into the storage device 5 at the starting point.

The road map data recorded on the map information recording medium 7 is recorded as shown in FIGS. 2 to 4. In other words, nodes such as intersections and road turns
A number (1, 2, 3,...) is assigned to each node as an identification code, and distance, width, direction, etc. are assigned to each link between nodes.
In addition to being subdivided with information such as prohibited areas,
Each road has a number (■, ■, ■,...
・) are added and recorded. "One road" here is one that is made up of multiple links, and although the figure shows a straight road, it is not limited to this, and can include curved or bent roads. It also includes things such as things.

Further, the central processing unit 2 performs the following control based on a control program. That is, when a starting point (node 6) and a destination point (node 26) are set, there are usually multiple candidate routes between the two points, but these multiple candidate routes are first As shown in Figures 2 and 3, the road ■ that intersects the starting point node 6, and the nodes with a shorter distance from the destination point node 26 on ■ are sequentially searched. 6-5-4--... - Nodes 6-12-18-... for road 0), and thereafter nodes searched as shown in FIG. 4 (for example, nodes 5.4-- for road ■) 3, ... (indicated by a black circle), road 0 intersects every node 12, 18, 24, ... (indicated by a black triangle) (for example, for node 5, roads ■, [phase ], for node 12 (■, ■), sequentially search for nodes that have a shorter distance from the destination node 26.Then, links between the searched nodes are connected to form a candidate route ( For example, node 6-5-
4-..., nodes 6-12-18-...) are the same road ■, where the destination point 26 exists in the process of this search.
■Node 2.8.14.20 or node 30.
29. When either of 28 or 27 is searched, after Ja, the links on the same road ■, ■ between that node and the destination point 26 are continued, the search in the process is finished, and a candidate route is created. Form. For example, if node 2 is searched, node 6-
Candidate route A of 2-26 is formed, and when node 30 is searched, candidate route B of node 6-30-26 is formed. In other words, for road ■, it is no longer necessary to search for other nodes 8, 14, and 20, and for road ■, it is no longer necessary to search for other nodes 2
Since there is no need to search for 9.28.27, the time required to search for a candidate route is shortened.

Once all candidate routes have been searched, the next step is to selectively search and determine the optimal route connecting both points, that is, a route that satisfies the conditions desired by the driver. This route search is performed based on input of the driver's desired conditions prior to departure, such as a route with a shorter total distance, a route with fewer turns, and a route with wider roads between the two points.

Next, the route determination operation by the central processing unit 2 will be explained based on the flowcharts of FIGS. 5 and 6.

First, as a step before determining a route, all candidate routes that can connect the starting point and the destination point are searched. In searching for this candidate route, first, the road where the starting point node 6 is located is obtained, but as shown in FIGS. 2 and 3, the road ■
, ■ are advanced by 1 (step 101). And first,
For example, it is determined whether the nodes 6, 5, 4, . If it is the same road ■, the search for the candidate route is finished, and if it is not the same road, the node 5.4.3 whose distance is shorter than the destination point node 26 is terminated.
, . . . are obtained continuously (step 103). The obtained node is set as the next search start node (step 104),
Thereafter, steps 1.1 to 104 are repeated to search for all candidate routes.

Once all of the candidate routes have been searched, the route with the shortest total distance and the least number of turns is searched among the candidate routes. First, the total distance is obtained from the calculation of each link by setting the first candidate route as the optimal route (step 11).
1). Similarly, the total distance of the second candidate route is obtained (step 112). Then, the first candidate route and the second candidate route are compared, and if the second candidate route is longer than the first candidate route by a certain ratio HD (for example, 100 m) or more, the process jumps to step 118, and if it is shorter, the process jumps to step 114. to move to. In step 114, if the first candidate route is longer than the second candidate route by a certain ratio MD or more, the process jumps to step 117, and if it is shorter, the process moves to step 115. In step 115, the number of turns of both routes is calculated, and in step 11
In step 6, the number of turns of both routes is compared, and if the number of turns of the first candidate route is less, the process jumps to step 118, and if it is more, the process moves to step 117. In step 117, the second candidate route is set as the optimal route and step 118
to move to. In step 118, it is determined whether the comparison has been completed for all candidate routes. If the comparison of all candidate routes has not been completed, the second candidate route is set as the optimal route and the process moves to step 119, and the second candidate route is set as the next reference optimal route and the process returns to step 112.
Processing up to step 118 is performed in the same manner as above for the third candidate route, and thereafter step 11 is performed for each candidate route.
The processes from step 2 to step 118 are repeated, and when the comparison between all candidate routes is completed, the optimal route is determined and the process ends.

Moreover, FIGS. 7 and 8 are flowcharts of other embodiments. This embodiment deals with route determination when there is a prohibited section. First, according to the flowchart of FIG. 7, a departure time and an expected arrival time at a destination point are set (steps 201 and 202).

Then, after passing through step 111 above, step 20
In step 3, it is determined whether or not there is a prohibited section during the travel time among the links constituting the candidate route. If there is a prohibited section, the process jumps to step 118, and from then on, another candidate route is sequentially selected. Similarly, it is determined whether there are any prohibited sections for the route, and if there are no prohibited sections,
The above steps 112 to 119 are processed, and the optimal route is finally determined.

Moreover, FIG. 9 and FIG. 1θ are flowcharts of another embodiment, in which a candidate route with a wide road is determined as the optimal route. In other words,
This takes into account the fact that wider roads are easier to drive on and are more likely to avoid traffic jams. First, in the flowchart shown in FIG. 9, a desired width is input at the start of travel (step 301).

Then, after passing through step 111, step 302
In step 118, it is determined whether there is a link narrower than the desired width among the constituent links of the candidate route, and if there is a narrow link, the process jumps to step 118 and from then on, another candidate route K is sequentially selected.
The width is similarly determined for each link, and if there is no narrow link, steps 112 to 119 are performed, and the optimal route is finally determined.

Furthermore, FIGS. 11 and 12 show other embodiments, taking into consideration the case where traffic is prohibited depending on the type of vehicle (small, large, special large). First, the vehicle type is input using the flowchart shown in FIG. 11 (step 401).

After passing through step 111, step 402
In step 118, it is determined whether or not the vehicle type specified in the route configuration link is prohibited from passing. If there is a prohibition, the process jumps to step 118, and thereafter, the width of another route is determined in the same way. is determined, and if there is no prohibition of passage, proceed from step 112 to step 1]9 above.
are processed, and the optimal route is finally determined.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, when determining a candidate route, if a node that exists on the same road as the node of the destination point is searched for, then from that node to the node of the destination point. A candidate route is formed by connecting links on the same road between the searched nodes and completing the search in the process, and the search for nodes between the searched nodes and the destination point is omitted, reducing the processing time. The search is shortened and can be performed quickly.

In addition, when determining the optimal route from among the searched candidate routes, by determining the candidate route with the shorter total distance between the starting point and the destination point and the fewer number of turns as the optimal route, it is possible to reach the destination point. This will shorten the time it takes to travel and extend the section where you can drive straight, allowing you to arrive at your destination faster.
You can drive comfortably without having to worry about changing directions.

In addition, when determining the optimal route from among the searched candidate routes, if there is a prohibited section among the links constituting the candidate route during the driving time of the vehicle, the candidate route is excluded from the candidates, so that the road is prohibited. You can drive without being hindered by the section.

In addition, when determining the optimal route from among the searched candidate routes, if there is a constituent link with a width less than a predetermined width, that candidate route is excluded from the candidates. etc. can be relatively avoided and the vehicle can run smoothly.

Furthermore, when determining the optimal route from among the searched candidate routes, if there is a prohibited section depending on the vehicle type in the constituent links, it is configured with a means to exclude that candidate route from the candidates. You can drive without being hindered by different prohibited areas.

[Brief explanation of the drawing]

The drawing shows an embodiment of a route determining device according to the present invention,
Figure 1 is a circuit diagram of the onboard navigation system, Figures 2 and 4
FIG. 5 is an explanatory diagram of route determination, FIGS. 5 and 6 are flowcharts explaining the route determination operation by the central processing unit, and FIG.
8 and 8 are flowcharts showing other embodiments, FIGS. 9 and 10 are flowcharts of other embodiments, and FIGS. 11 and 12 are flowcharts of other embodiments. (Brief explanation of drawings showing main parts) ・In-vehicle navigation device 2・・Central processing unit・Vehicle speed sensor 4・・Direction sensor・Storage device 6・
・Display device ・Map information recording medium

Claims (5)

[Claims] (1) A route determining device that sets a starting point and a destination point on a road in map information, searches for multiple candidate routes connecting the two points, and determines the optimal route from among the searched candidate routes. Therefore, when searching for candidate routes, the roads in the above map information are subdivided into nodes with identification codes and links between the nodes, and the media in which each road is recorded with an identification code are used. We sequentially search for nodes that have a shorter distance from the nodes of the destination point that exist on roads that intersect with the nodes of the point, and then search for nodes that are shorter in distance from the nodes of the destination point that exist on the roads that intersect with the nodes of the point. A candidate route is formed by sequentially searching for nodes with a shorter distance between them, and links between the searched nodes are made consecutive, and in the process of this search, nodes that are on the same road as the destination node are searched for. and a means for forming a candidate route by subsequently connecting links on the same road from that node to a destination point, and completing the search in that process. decision device. (2) In determining the optimal route from among the searched candidate routes, the system includes means for determining a candidate route that has a shorter total distance between the starting point and the destination point and has fewer turns as the optimal route. The route determining device according to claim 1, wherein the route determining device is configured such that: (3) In determining the most accessible route from among the searched candidate routes, if there is a prohibited section among the links constituting the candidate route during the travel time of the vehicle, it includes means for excluding that candidate route from the candidates. 3. The route determining device according to claim 1, wherein the route determining device is configured as follows. (4) In determining the optimal route from among the searched candidate routes, if there is a constituent link with a width less than a predetermined width, the present invention is characterized by comprising means for excluding that candidate route from the candidates. The route determining device according to claim 1, 2 or 3. (5) In determining the optimal route from among the searched candidate routes, if there is a section where traffic is prohibited depending on the vehicle type among the constituent links, the system is configured to include means for excluding the candidate route from the candidates. Claims 1 and 2,
5. The route determining device according to 3 or 4.