JP2000346665A - Apparatus and medium for guiding route for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely search for a route to a destination by automatically searching for the route to the destination also with the use of roads when the roads in map data for display have a width of not smaller than a predetermined value. SOLUTION: A navigation ECU 10 searches for routes to a destination with the use of map data stored in a map database 14, and outputs obtained routes to a display 16 and a speaker 18. The map database 14 stores map data for display and map data for search. When the map data for search is not present in the neighborhood of the destination, map data for display having a width of not smaller than a predetermined value is used for assisting the map data for search, thereby searching for routes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle route guidance device, and more particularly to a technique for searching for a route to a destination.

[0002]

2. Description of the Related Art Conventionally, there is known a route guidance device that guides a right turn or a left turn at an intersection on a screen or by voice at an appropriate timing while a vehicle is running and guides the user to a desired destination. The route to the destination is usually performed by reading map data for search stored in the storage device and selecting the route with the smallest total cost from the current location to the destination. That is, the search map data is
An actual road is constituted by links connecting nodes and each node, and the cost of each link is calculated based on distance, traffic regulation, and the like, and a route that minimizes the total link cost is searched for by the Dijkstra method or the like. Incidentally, Japanese Patent Application Laid-Open No. H10-62
No. 183 discloses an example of such a navigation system.

[0003]

However, usually,
The map data (or map data) stored in the storage means is created based on a map created by a predetermined institution, and the accuracy of the road width of the base map is relatively low and exists in the map. It is not possible to determine whether or not a certain road may be used as search data (ie, whether or not a vehicle can actually pass), and a field survey is performed to determine whether or not it can be used as search data. That is the current situation.

[0004] Therefore, even if the actual width of the road is such that it does not impede vehicle traffic, roads for which field surveys have not been completed are excluded from the route search, and the road to the vicinity of the destination is excluded. May be obtained, but a route closer to the destination or the route to the destination itself may not be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to automatically determine whether or not it can be used as search map data even if no field survey or the like is performed. Another object of the present invention is to provide a device and a medium that can reliably search for a route to a destination using the device.

[0006]

In order to achieve the above object, the present invention is a vehicle route guidance apparatus for searching for a route to a destination, and stores display map data and search map data. Storage means, width determination means for determining whether a road in the display map data has a width equal to or greater than a predetermined value, the search map data, and display map data having a width equal to or more than the predetermined value And a calculating means for searching for a route to the destination by using a computer. By performing a search using not only the search map data but also display map data having a width equal to or greater than a predetermined value, a route to a destination can be obtained more reliably. In addition,
By using a road having a width equal to or greater than a predetermined value, the possibility of vehicle traffic can be secured.

Here, the display map data may be map data obtained from a satellite photograph. According to the satellite photograph, highly accurate map data can be obtained, and it can be easily determined whether or not the width is equal to or more than a predetermined value.

Further, the present invention further comprises a regulation judging means for judging a traffic regulation of the display road, wherein the calculating means has the search map data and a width not less than the predetermined value. And searching for a route to the destination by using map data for display that can be passed.
By considering traffic restrictions in addition to the width, it is possible to eliminate the possibility that a road that cannot be used is used for route search, and obtain a route that can more reliably reach the destination.

Further, the present invention is characterized in that the calculating means searches the route by making the cost of the display map data larger than the cost of the search map data of the same distance. In the present invention, since the display map data for which no field survey has been performed is used as the search map data, there may be a case where there is actually a problem in traffic even in consideration of the width and traffic restrictions. By executing such a route search by passing such risks on to costs, a reliable route can be obtained.

The present invention also provides a computer-readable medium for recording a program for searching for a route to a destination. The program causes the computer to read at least the display map data stored in the storage means and determine whether or not it has a width equal to or greater than a predetermined value, and search map data stored in the storage means. And using the display map data having a width equal to or greater than the predetermined value to search for a route to the destination.

[0011] Here, the program can further cause the computer to determine the traffic regulation of the display road, and the program determines that the cost of the display map data is the same as the search map at the same distance. The route can be searched at a higher cost than the data cost.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of this embodiment. The GPS 12 receives a radio wave from a GPS satellite and detects the position of the own vehicle as an absolute position (latitude and longitude). The detected position data is stored in the navigation ECU 10.
To supply. Instead of the GPS, a DGPS that receives a GPS position error signal transmitted by FM multiplex broadcasting or the like and corrects the position detected by the GPS may be used. Further, the position of the vehicle can be detected by combining a distance sensor and a direction sensor.

Navigation ECU (electronic control unit) 1
Numeral 0 is constituted by a microcomputer and searches for a route to a destination. The destination is specified by the user, and the route to the destination is searched by the Dijkstra method using the search map data stored in the map database 14. The route obtained by the search is displayed on the display 16. Further, voice synthesis is performed based on the obtained route data, and guidance such as “turn right at the next intersection” is provided from the speaker 18. The navigation ECU 10 reads the display map data around the current position from the map database 14 and displays the read map data on the display 16 to notify the driver of the current position.

The map database 14 is constituted by a CD-ROM or a DVD-ROM, and stores display map data and search map data. As described above, the display map data is read and displayed on the display 16, and the search map data is used at the time of the route search. Conventionally, the display map data stored in the map database 14 is obtained by digitizing a map created by a predetermined organization, and the search data is obtained from the display map data based on a link cost based on a field survey. And the traffic regulation information (one-way traffic or time-dependent traffic closure) is added. The display map data in the present embodiment is high-precision map data obtained from a satellite photograph. This map data has higher accuracy than the conventional road width, and the width data of an arbitrary road is determined at least in units of 1 m. The navigation ECU 10 determines whether or not the display map data can be used as the search map data based on the width data of each road.

The input device 20 is composed of operation buttons or touch switches, and a user inputs a destination or a waypoint. The input destination is the navigation ECU 10
Supplied to

The configuration of this embodiment is as described above, and the navigation ECU 10 will be described with reference to the flowchart of FIG.
Will be described in detail.

In FIG. 2, first, the navigation ECU
10 reads out the map data on the destination side from the map database 14 (S101). If the road is a search road for which a field survey has been completed (S102), a route to the destination is searched using the data using the Dijkstra method or the like. On the other hand, if the road to the destination, that is, the road to or near the destination is not a search road for which field survey has been conducted, the display map data on the destination side is read to determine whether a road exists. A determination is made (S103). If there is road data that reaches or is close to the destination in the display map data, it is determined whether the width of the road is a predetermined value, for example, 5.5 m or more (S104).
The width data may be added to a road in advance and held as map data, or the width may be calculated from the road data. The predetermined value is preferably determined from the viewpoint of whether or not the vehicle can pass, and may be set to a value of 6 m or more instead of 5.5 m. Of course, the predetermined value can be set by the user, which is effective when the user is a beginner of driving and does not like a narrow road.

When a road having a width of 5.5 m or more is present at the destination (or near the destination), the navigation ECU 10 newly includes this road data in the search data and executes a route search. (S105). Even if road data exists in the display map data, if the width is less than the predetermined value, it cannot be used for vehicle traffic, so this road is not included in the search data, and only the existing search data is used. (S107). Then, the obtained route is displayed on the display 16 and provided to the user (S106).

As described above, when high-precision display map data is used, and road data having a width of a predetermined value exists in the display map data, a route search calculation is executed with the aid of the search map data. By doing so, a route that eventually reaches or is closer to the destination is obtained, and the usability of the system is improved.

FIG. 3 schematically shows route search results in the present embodiment and the conventional system. In the figure, the road 1 in the route search map data is located near the destination D.
It is assumed that 00 and the road 200 in the display map data exist, and the destination D exists facing the road 200.
In the conventional route search calculation, since the route to the destination is searched using only the search map data, the search route 30 ends on the search road 100, but in the present embodiment, the destination D Road 20 in the nearby display map data
0 exists and the width of the road is equal to or larger than a predetermined value, the route is searched for by including it in the search map data.
The search route 32 to the destination D is obtained by using 0, so that the user can reliably reach the destination D.

When using the display map data as search data in S105, it is necessary to decompose the road data into nodes and links and calculate the cost of each link. Nodes can be replaced with roads connecting the nodes as links, and the length (distance) of the links can be directly used as the link cost.
However, when the link length is used as the link cost, it is preferable to increase the cost as compared with the search road data. That is, when there are links of the same length, the link cost is higher in the case of display map data than in the case of search map data. This means that in the case of search map data, site surveys etc. are performed to confirm that vehicles can pass, while in the case of display map data,
Although it is determined that the width of the vehicle is equal to or greater than the predetermined value and that the vehicle can pass, it is considered that there is a certain degree of risk since actual field surveys have not been performed to confirm the vehicle. Therefore, in order for the display map data to be selected as the final route, the distance must be short (for the same distance, the search map data is selected because the cost is smaller). Of course, when the destination cannot be reached by the search map data alone, and the destination can be reached when the display map data is included in the search map data, a route that can reach the destination is selected.

It is also preferable to further determine whether or not the traffic is restricted when the width is equal to or more than the predetermined value in S104. The data relating to the traffic regulation can be obtained by newly providing a communication device in FIG. 1 and receiving information from the road control center, or the data relating to the traffic regulation (for example, one-way data) is added to the display map data. It can be added in advance. When the data is included in the search data in S105, more reliable route search can be performed by including the data relating to the traffic regulation in consideration. For example, even if the width is 5.5 m or more, roads that are closed due to construction are not included in the search data. If the width is 5.5 m or more and the road is one-way, the link cost in the opposite direction is calculated. Significantly increase, and so on.

As described above, in the present embodiment, a road whose width is equal to or more than a predetermined value is used as search map data, thereby searching for a road for which no field survey has been performed, and increasing the route to the destination. It is possible to search with probability.

The processing shown in FIG. 2 can be realized by installing a processing program in the navigation ECU 10 and the CPU of the navigation ECU 10 sequentially executing the installation program. Such a processing program can be recorded on any medium capable of holding information electromagnetically, chemically or optically, such as a CD-ROM, DVD, floppy disk, or hard disk.

In the present embodiment, map data obtained from a satellite photograph is used as the display map data having sufficient accuracy (at least about 1 m) for the width, but it is obtained from other sources. Of course, it is also possible to use map data. Then, even when the width data does not exist in the map data itself, for example, data specifying a road whose width is to be determined (position data of the road, etc.)
May be transmitted to a road control center or the like, and the determination may be made by receiving the width data of the road from the road control center.

[0027]

As described above, according to the present invention,
If the road in the display map data has a width equal to or greater than a predetermined value, the route to the destination is automatically searched using the road, so that the route to the destination can be more reliably searched than before. it can.

Further, according to the present invention, since the route search is further performed in consideration of the traffic restriction of the display road, the use of the display road which cannot be passed is prevented, and the route which can reach the destination is prevented. Can be reliably obtained.

According to the present invention, when the display map data is used as the search map data, the cost of the display map data is increased as compared with the cost of the search map data at the same distance. A search that takes into account risks that have not gone through a field survey becomes possible, and a highly reliable route search becomes possible.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of an embodiment of the present invention.

FIG. 2 is a processing flowchart according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a route search result according to the embodiment of the present invention.

[Explanation of symbols]

10 navigation ECU, 12 GPS, 14 map database, 16 display, 18 speaker.

Claims (7)

[Claims] 1. A vehicle route guidance device for searching for a route to a destination, comprising: storage means for storing display map data and search map data; and wherein a road in the display map data is equal to or more than a predetermined value. Width determination means for determining whether or not the width of the, the search map data, and a calculation means for searching for a route to the destination using display map data having a width of the predetermined value or more, A route guidance device for a vehicle, comprising: 2. The vehicle route guidance device according to claim 1, wherein the display map data is map data obtained from a satellite photograph. 3. The apparatus according to claim 1, further comprising: regulation judging means for judging a traffic regulation of said display road, wherein said arithmetic means comprises said map data for search. And a route guide device for a vehicle having a width equal to or greater than the predetermined value and searching for a route to the destination using displayable map data. 4. The apparatus according to claim 1, wherein said calculating means sets a cost of said map data for display to be larger than a cost of said map data for search having the same distance, and sets a route. A route guidance device for a vehicle, characterized by searching for a vehicle. 5. A computer-readable medium for recording a program for searching for a route to a destination, comprising:
The program causes the computer to read at least the display map data stored in the storage unit and determine whether or not the display has a width equal to or greater than a predetermined value.The search map data stored in the storage unit, A medium that causes a route to the destination to be searched using display map data having a width equal to or greater than the predetermined value. 6. The medium according to claim 5, wherein the program further causes the computer to determine traffic regulation on the display road. 7. The medium according to claim 5, wherein the program causes the cost of the display map data to be larger than the cost of the search map data having the same distance to search for a route. A medium characterized by the above.