JP3517029B2 - In-vehicle route search device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention calculates a recommended route by using a well-known Dijkstra method or the like for a preset route from a starting point to a destination, and calculates the recommended route around the surrounding roads. The present invention relates to a vehicle-mounted route search device displayed together with a map.

[0002]

2. Description of the Related Art An on-vehicle route for calculating a recommended route by performing a route search from a starting point to a destination based on map display data and route search data stored in a map storage memory such as a CD-ROM. Search devices are known.

FIG. 10 is a flowchart showing a recommended route search process of a conventional vehicle-mounted route search device. Figure 10
In step S201, the route search is started from the departure point and the route search range is gradually expanded. In step S202, the route search data around the reference node is read from the map storage memory. For example, in FIG. 9, when the route from node A to node C to node C is selected as a recommended route candidate, route search data around node C is read.

In step S203, all the adjacent nodes connected to the reference node are extracted from the read route search data. In the case of FIG. 9, the nodes a to f connected to the reference node C are extracted. In step S204, of the extracted nodes a to f, a node satisfying a predetermined condition (for example, a node reachable in the shortest time) is selected as a final adjacent node. In step S205, it is determined whether or not the route has been searched to the destination. If the determination is negative, the process returns to step S202,
If the determination is positive, the process ends.

FIG. 11 is a data layout diagram of route search data stored in a map storage memory of a conventional vehicle-mounted route search device. As shown in the figure, the route search data is composed of link information, and each link information is classified and arranged in units of mesh areas (for example, 16 km square).

[0006]

In the conventional vehicle-mounted route search device, as in step S203 of FIG. 10, all link information adjacent to the reference node is extracted, and the road type in the extracted link information is extracted. The adjacent node was selected based on the information. That is, conventionally, the route search calculation is performed in consideration of all the nodes connected to the individual nodes. For example, even when a national road is selected as a recommended route candidate in the middle of the calculation, a road other than the national road is selected. The route was searched including the types of roads. Therefore, even for roads such as ordinary roads and narrow roads that cannot be clearly targeted for route search, each road must be selected once as a recommended route candidate, and the calculation time required for route search becomes long. There was a problem.

An object of the present invention is to provide an in-vehicle route search device capable of calculating a recommended route in a short time while maintaining the calculation accuracy.

[0008]

When describing the present invention in association with Figure 1 showing an embodiment [SUMMARY OF], a first aspect of the invention, a road map for storing information (node information) about the node required ROUTE SEARCH On-vehicle equipped with a storage means 7 and a recommended route calculation means for calculating a recommended route by performing a route search from a set vehicle position to a destination based on the node information stored in the road map storage means 7. It is applied to a route search device, and the road map storage means 7 stores (1) node information.
As a report, at least two of the first and second road types
Information about the roads of the first road type is stored (2)
Another has a higher priority than the second road type,
(3) Of the node information, the first road type road and the first road type
Node information of the intersection where the roads of 2 road types intersect
Is the node information of the first road type with high priority.
By being stored , the above object is achieved. The invention according to claim 2 provides information on nodes required for route search.
Road map storage means 7 for storing information (node information), and
Based on the node information stored in the road map storage means 7 of
Based on this, route search from the set vehicle position to the destination
Equipped with recommended route calculation means to go and calculate the recommended route
It is applied to the in-vehicle route search device and is a road map storage means.
7 includes (1) at least the first node information as node information.
And information about two roads of the second road type is stored.
(2) The first road type is higher than the second road type
It has a priority, and (3) of the node information,
The road of the first road type and the road of the second road type intersect
The node information of the intersection is the first road type with high priority.
Stored as separate node information, (4) node information
Is stored in the memory area allocated for each road type
Thereby, the above object is achieved. The invention according to claim 3 is the information (node
Information), a road map storage means 7, and this road map.
Based on the node information stored in the storage means 7,
Recommended by conducting a route search from a fixed vehicle position to the destination
For vehicles equipped with recommended route calculation means for calculating routes
It is applied to a route search device, and the road map storage means 7
(1) Node information is geographically divided into multiple areas
It is stored for each area, and (2) as node information,
At least two roads of the first and second road types
Information is stored, and (3) the first road type is the second
It has a higher priority than the road type, and (4) node
Of the information, the roads of the first road type and the roads of the second road type
The node information of intersections that intersect with roads has a high priority.
To be stored as node information for the first road type
Therefore, the above object is achieved. The invention according to claim 4
Is a vehicle-mounted route search according to any one of claims 1 to 3.
In the search equipment, the recommended route is calculated during the calculation of the recommended route.
Determines the road type, and
Recommended route to calculate the recommended route based on the route information.
It constitutes a computing unit.

[0009]

In the invention described in claim 1, the node information
Then, the road of the first road type and the road of the second road type are
The node information of the intersecting intersections is the information of the first
It is stored as road type node information. In the invention according to claim 2, the node information is assigned for each road type.
Stored in the memory area. According to the invention of claim 3, the node information is geographically divided into a plurality of areas.
Memorized about the area. In the invention according to claim 4, the road type of the recommended route is determined while the recommended route is being calculated, and the node information related to the determined road type (for example, the node of the same road type as the determined road type) is determined. information)
Use only to perform route search.

Incidentally, in the section of means and action for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for the purpose of making the present invention easy to understand. It is not limited to.

[0011]

1 is a block diagram of an embodiment of a vehicle-mounted route search device according to the present invention. In FIG. 1, reference numeral 1 denotes a current position detection device for detecting the current position of the vehicle, for example, a direction sensor for detecting the traveling direction of the vehicle, a vehicle speed sensor for detecting the vehicle speed, and a GPS signal from a GPS (Global Positioning System) satellite. It is composed of a GPS sensor and the like.

Reference numeral 2 is a control circuit for controlling the entire apparatus,
It consists of a microprocessor and its peripheral circuits. Reference numeral 3 is an input device for inputting a destination of the vehicle, and 4 is a DRA for storing vehicle position information detected by the current position detection device 1.
M and 5 are image memories for storing image data to be displayed on the display device 6, and the image data stored in the image memory 5 are appropriately read and displayed on the display device 6.

Reference numeral 7 is a map storage memory for storing various data for performing road map display, route search, map matching, etc., and is composed of, for example, a CD-ROM device or a magnetic recording device. The map storage memory 7 stores map display data composed of information about road shapes and route search data composed of branch point information and intersection information not directly related to road shapes. The map display data is mainly used when the road map is displayed on the display device 6, and the route search data is mainly used when the recommended route is calculated.

FIG. 2 is a data structure diagram of route search data. As shown in the figure, node information indicating a connection relationship with another node is stored for each connection point (node) of a link, which is the minimum unit for expressing a road. Each piece of node information consists of own node information and adjacent node information, and the position coordinates of the node are stored in the own node information. On the other hand, in the adjacent node information, as shown in the figure, the adjacent node number, the link number from the own node to the adjacent node, the link cost of the link, and the traffic regulation information of the link are stored. . Also, each node information is stored in the link connection order, and the node number of the own node can be grasped by the stored order. Therefore, it is not necessary to store the node number of the own node, and the memory capacity can be reduced.

FIG. 3 is a data layout diagram of route search data in the map storage memory 7. As shown,
Each piece of node information forming the route search data is classified in units of a mesh area (for example, 16 km square), and the node information belonging to each unit is classified according to the road type. There are, for example, six types of roads in FIG. 4, and each road type is given a priority. In FIG. 4, the higher the column, the higher the priority.

The nodes at the points where the roads of different road types intersect are managed according to the highest road type so that the node information is not stored in the map storage memory 7 in duplicate. . For example, a node where a national road and a general road intersect is managed as a node on the national road. In the following, the data placement area of the route search data in the map storage memory 7 is associated with the road type, and the toll / highway data area, national road data area, prefectural road data area, main local road data area, general road data Area and ferry data area.

FIG. 5 is an example of a road map in which highways, national roads, main local roads and general roads are close to each other.
In the case of FIG. 5, the node information regarding the nodes n1 and n2 is stored in the highway / toll road data area in the nodes n3, n4, n5.
The node information regarding n6, n7, and n9 is in the national road data area, the node n8 is in the main local road data area, and the node s
1, s2, s3 are arranged in the general road data area, respectively.

FIG. 6 is a flow chart showing an outline of the main processing performed by the control circuit 2. In step S1 of FIG. 6, the vehicle position is detected by using the current position detection device 1, and a start point of the route search is set on a route searchable route near the detected vehicle position. In step S2, the destination information input by the user with the input device 3 is fetched, and the end point of the route search is set on the road where the route search is possible near the destination.

In step S3, a recommended route search process, which will be described later, is performed to calculate a recommended route from the start point to the end point set in steps S1 and S2.
In step S4, the map drawing process shown in detail in FIG. 7 is performed, and the data to be displayed on the display device 6 is stored in the image memory 5. First, in step S21 of FIG. 7, map display data around the vehicle position is read from the map storage memory 7. Next, in step S22, a part of the read map display data is drawn (stored) in the image memory 5. In step S23, the data necessary for displaying the recommended route calculated in step S3 of FIG. 6 is drawn (stored) in the image memory 5 in an overlapping manner.

When the process of step S23 of FIG. 7 is completed, the process proceeds to step S5 of FIG. 6, the data stored in the image memory 5 is read, and the recommended route and the road map around it are displayed.

FIG. 8 is a detailed flowchart of the recommended route search process in step S3 of FIG. Step S of FIG.
In 101, a route search is started by the well-known Dijkstra method or the like with the starting point set in step S1 of FIG. 6 as a starting point. In step S102, the road type of the recommended route is determined based on the route search result up to the middle. For example,
In FIG. 9, when the route search is started with the node A as the starting point of the route search and a national road passing through the nodes A, B, and C is selected as a recommended route candidate, the road type of the recommended route is the national road. To do.

In step S103, step S102
The node information related to the road type determined in step 1 is read from the map storage memory 7. In step S104, a process of extracting node information that can be a candidate for selection is performed from the node information read in step S103. For example, in FIG.
When the route search is completed up to the node C, the node information regarding the nodes b, d, and f that are adjacent to the node C and on the national road is extracted.

In step S105, step S104
An adjacent node on the recommended route is selected using the node information extracted in. For example, in the case of FIG. 9, the node b in the destination direction is selected as the adjacent node. Step S10
In 6, it is determined whether or not the route search is performed up to the destination (route search end point). If the determination is affirmative, the process returns, and if the determination is negative, the process returns to step S103.

As described above, in this embodiment, the node information that can be used for the route search calculation is classified according to the road type and stored in the map storage memory 7. When the departure place and the destination are set, the route search calculation is started with the departure place (route search start point) as the starting point, and the route search range is gradually expanded. When the road type of the recommended route is determined during the route search, thereafter, the route search is performed using only the node information corresponding to the determined road type. As a result, at an intersection where a plurality of roads of different road types intersect, a route search can be performed using only node information of a specific road type, and the time required for the route search can be significantly shortened compared to the related art. .

In the above-described embodiment, the example in which the node information that can be used for the route search calculation is classified according to the road type and stored in the map storage memory 7 is described. You may classify and store for every classification. Further, the types of road types and the priorities are not limited to those in the above embodiment.

In the above-mentioned embodiment, when the road type of the recommended route is determined during the route search, the node information of the same road type as the determined road type is read.
Instead of reading only the node information of the same road type, node information close to the determined road type may be read together. For example, when the determined road type is a national road, the route search may be performed by reading the node information about the national road and the prefectural road.

In the above embodiment, the map storage memory 7
8 corresponds to the road map storage means, the flowchart of FIG. 8 corresponds to the recommended route calculation means, step S102 of FIG. 8 corresponds to the road type determination means, and steps S103 to S106 of FIG. 8 correspond to the final route calculation means.

[0028]

As described in detail above, the first to third aspects are described .
According to the third aspect of the invention, since the node information is classified for each road type and stored so as not to be duplicated, only the node information of the road type necessary for the route search can be read, and the calculation time of the recommended route can be shortened. . In addition, for points at which roads of different road types intersect, node information is stored in association with the road type having the highest priority.
The node information is not redundantly stored and the memory capacity can be reduced . According to the invention described in claim 4, when the road type of the recommended route is determined during the calculation of the recommended route, the route search is thereafter performed only on the node information related to the determined road type. The route search range can be limited so as not to affect the calculation accuracy, and the recommended route calculation time can be shortened.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of an in-vehicle route search device according to the present invention.

FIG. 2 is a data configuration diagram of route search data.

FIG. 3 is a data layout diagram of route search data in a map storage memory.

FIG. 4 is a diagram in which road types are classified according to priorities.

FIG. 5 is a diagram showing an example of a road map in which highways, national roads, main local roads, and general roads are close to each other.

FIG. 6 is a flowchart showing an outline of main processing performed by a control circuit.

7 is a detailed flowchart of the map drawing process in step S4 of FIG.

FIG. 8 is a detailed flowchart of a recommended route search process in step S3 of FIG.

FIG. 9 is a diagram showing an example in which a route from node A to node C to node C is selected as a recommended route candidate.

FIG. 10 is a detailed flowchart of a conventional recommended route search process.

FIG. 11 is a data layout diagram of route search data stored in a conventional map storage memory.

[Explanation of symbols]

1 Current location detector 2 control circuit 3 input devices 4 DRAM 5 image memory 6 Display device 7 map memory

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Claims (4)

(57) [Claims] 1. A information about nodes necessary ROUTE SEARCH (Roh
Based on the road map storage means that stores the road information) and the node information stored in the road map storage means, it is recommended to perform a route search from the set vehicle position to the destination and calculate a recommended route. In the vehicle-mounted route search device including route calculation means, the road map storage means includes (1) at least first and second node information as the node information.
Information about two roads of the second road type is stored, and (2) the first road type has a higher priority than the second road type.
It has a rank, (3) of the node information, the first road type road
Information of the intersection where the road and the road of the second road type intersect
The information is the node information of the first road type with high priority.
An in-vehicle route search device characterized in that it is stored in memory . 2. Information (node) necessary for a route search
Map information), and the node information stored in the road map storage means.
Route search from the set vehicle position to the destination based on
With the recommended route calculation means to search for and calculate the recommended route
In the vehicle-mounted route search device including : (1) at least a first and
Information about two roads of the second road type is stored, and (2) the first road type has a higher priority than the second road type.
It has a rank, (3) of the node information, the first road type road
Information of the intersection where the road and the road of the second road type intersect
The information is the node information of the first road type with high priority.
Stored Te, (4) the node information assigned to each road type
An in-vehicle route search device characterized by being stored in a memory area . 3. Information (node information required for route search )
Map information), and the node information stored in the road map storage means.
Route search from the set vehicle position to the destination based on
With the recommended route calculation means to search for and calculate the recommended route
In the in-vehicle route search device including : (1) the node information is geographically divided into a plurality of areas.
Stored for each area, (2) As the node information, at least the first and
Information about two roads of the second road type is stored, and (3) the first road type has a higher priority than the second road type.
It has a rank, (4) of the node information, the first road type road
Information of the intersection where the road and the road of the second road type intersect
The information is the node information of the first road type with high priority.
An in-vehicle route search device characterized in that it is stored in memory . 4. The vehicle-mounted device according to any one of claims 1 to 3.
In the route search device for The recommended route calculation means is Determine the road type of the recommended route during the calculation of the recommended route
Then Based on the node information related to the determined road type
Based on the vehicle route, the recommended route is calculated based on
Road search device.