JPH1019593A - On-vehicle navigator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle navigator capable of calculating the time needed for reaching a destination much more accurately at the time of seaching for a guiding route, and capable of searching for a guiding route which makes it possible to reach the destination in the shortest time. SOLUTION: Link travel times are extracted out of a light beacon or wave beacon received by a beacon receiver 5 or traffic information received through the medium of an FM multiplex broadcast received by an FM multiplex receiving unit 6 are stored in a memory. In this memory, the average values of the link travel times in the past four weeks, for example, are stored separating them at every ten minutes. A navigator body 1 calculates a required time up to a destination, on the basis of the latest traffic information received by the aid of the beacon receiver 5 or FM multiplex receiving unit 6. And, in the case of one hour or less for example, a guiding route is searched using the latest traffic information, and in the case of more than one hour a guiding route for the part exceeding one hour is searched using data stored in the memory.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-vehicle navigation device for searching for an optimal guide route to a destination and guiding a user along the guide route, and more particularly to a vehicle-mounted navigation device which transmits the guide route from outside via radio waves or light. Receiving incoming traffic information,
The present invention relates to an in-vehicle navigation device that searches for a guidance route to a destination using this traffic information.

[0002]

2. Description of the Related Art An on-vehicle navigation device includes a map data storage device such as a CD-ROM or an IC card in which map data is recorded, a display device, a gyro and a GPS.
(Global Positioning System) and a vehicle movement detecting device for detecting the current position and current direction of the vehicle such as a vehicle speed sensor. The map data including the current position of the vehicle is read from the map data storage device, and based on the map data. Draws a map image around the vehicle position on the display device, and superimposes and displays the vehicle position mark (location) on the display screen, and scrolls or displays the map image according to the movement of the vehicle. By fixing it on the screen and moving the vehicle position mark, it is possible to see at a glance where the vehicle is currently traveling.

[0003] Normally, a navigation system for a vehicle is provided with a route guidance function that enables a driver to easily travel to a desired destination without making a mistake on a road. According to this route guidance function, the lowest cost route from the starting point to the destination using the map data is automatically searched by performing a simulation calculation such as the horizontal search method or the Dijkstra method, and the searched route is guided. The route is stored as a route, and during driving, the guidance route is drawn on the map image in a different color from the other roads and displayed thicker, or displayed on the screen, or a certain distance to the intersection where the vehicle should change the route on the guidance route When approaching, the driver can easily grasp the optimal route to the destination by drawing an arrow indicating the route at the intersection where the route should be changed on the map image and displaying it on the screen. I have to.

The cost is a value obtained by multiplying a constant according to a road width, a road type (such as a general road or an expressway), a right turn, a left turn, and the like based on the distance, a predicted traveling time of the vehicle, and the like. , The degree of appropriateness as a guidance route is quantified. Even if there are two routes having the same distance, the cost differs depending on whether the user specifies, for example, whether to use a toll road, or gives priority to distance or time.

A map stored in a map data storage device such as a CD-ROM has a longitude width of an appropriate size according to a scale level such as 1/12500, 1/25000, 1/50000, and 1/100000. Roads and the like are stored as a coordinate set of vertices (nodes) represented by longitude and latitude. A road is formed by connecting two or more nodes, and a portion connecting the two nodes is called a link. The map data includes (1) a road layer including a road list, a node table, an intersection configuration node list, and the like; (2) a background layer for displaying roads, buildings, facilities, parks, rivers, and the like on a map screen; (3) Administrative division names such as municipalities,
It is composed of a character / symbol layer for displaying characters such as road names, intersection names and building names, and map symbols.

In recent years, traffic information (traffic congestion information, accident information, road closure information, traffic regulation information, etc.) sent from outside the vehicle is received, and the traffic information is used to determine the road or road on which traffic congestion or an accident has occurred. Navigation devices have been developed that can search for a guidance route while avoiding closed roads. According to this type of navigation device, it is possible to reach a destination in a short time without passing through a road where traffic congestion or an accident has occurred.

[0007]

However, even if the user travels along the guide route searched based on the traffic information, when the vehicle arrives at a point where there was no traffic at the time of receiving the traffic information, the traffic congestion does not occur. It has occurred, and it may take some time because it ran along the guidance route. For example, as shown in FIG. 7, there is no traffic congestion at the point B when the vehicle passes the point A on the expressway, and the vehicle travels along the guidance route (indicated by a thick line in the figure) searched using the traffic information at the point A. Also, when the vehicle arrived at the point B, congestion occurred at the confluence point surrounded by the broken line in the figure, and as a result, traveling on the route shown in the figure C could reach the destination D in a shorter time There is that.

Accordingly, an object of the present invention is to provide an in-vehicle navigation device which can calculate a time required to reach a destination at the time of route search more accurately and searches for a guidance route which can reach the destination in the shortest time. To provide.

[0009]

The object of the present invention is to provide a vehicle-mounted navigation device for searching for a guide route to a destination based on traffic information sent from the outside. And past data storage means for storing past traffic information separately for each time, and the latest traffic information obtained via the past traffic information and the traffic information receiving means stored in the past data storage means. And a guidance route searching means for searching for the guidance route using the navigation device.

In the present invention, since the past data storage means stores the past traffic information, based on the past traffic information, it is possible to know the condition of the road through which the vehicle will pass at the time when the vehicle passes. it can. For example, it is assumed that traffic information for every 10 minutes is recorded in the past data storage means for one week. In general, traffic congestion on a road is greatly related to the day of the week and the time. Therefore, using traffic information of the past same day of the week stored in the past data storage means, the traffic congestion to occur and the traffic congestion You can know the degree of traffic jam that will be resolved.

According to the present invention, the past traffic information is stored in the past data storage means, and the cost of the road at the time when the vehicle passes is calculated using the past traffic information. It is possible to calculate costs taking into account road conditions such as traffic congestion that will be eliminated from now on. As a result, it is possible to more accurately grasp the time required to reach the destination, and to obtain a guidance route that can reach the destination in the shortest time.

[0012] For a guide route that is relatively close to the departure point (for example, a range that can be reached within a predetermined time), the latest traffic information obtained through the traffic information receiving means is used. Is preferred. On the other hand, if the travel time from the departure point to the destination is long, the road conditions acquired from the traffic information receiving means are likely to change on the way, so the past traffic information stored in the past data storage means is used. Is preferred. Therefore, the time required to reach the destination is calculated using the latest traffic information obtained via the traffic information receiving means, and if the required time exceeds a certain time, a guidance route traveling within the certain time Is preferably searched for based on the latest traffic information, and a guidance route exceeding the predetermined time is searched using past traffic information recorded in the past data storage means.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram illustrating a configuration of a vehicle-mounted navigation device according to an embodiment of the present invention. Reference numeral 1 denotes a navigation device main body constituted by a microcomputer. Reference numeral 2 denotes a liquid crystal monitor (display device). The navigation device main body 1 displays a map near the current position of the vehicle on the liquid crystal monitor 2, guides a route from a departure point to a destination, a vehicle position mark, and the like. Display the guidance information.

Reference numeral 3 denotes a CD-ROM storing map data composed of road layers, background layers, character / symbol layers, and the like for each scale, and 4 denotes the current position of the vehicle, the direction of the vehicle, the speed of the vehicle, and the like by satellite navigation. It is a GPS receiver to detect. Reference numeral 5 denotes a beacon receiver, and the beacon receiver 5
Receives an optical beacon or a radio beacon output from a transmitter provided along a road. Reference numeral 6 denotes an FM multiplex receiving unit that receives traffic information multiplexed on FM broadcasts. Optical beacons and radio beacons are used to provide traffic information in a small area, but provide relatively detailed traffic information. On the other hand, the communicable range of FM multiplex broadcasting is extremely wide (for example, the entire Kanto area), but the information density is relatively low.

7 is a gyro for detecting the rotation angle of the vehicle;
Reference numeral 8 denotes a vehicle speed pulse detector that detects a vehicle speed pulse generated as the vehicle moves, 9 denotes a traffic information data memory that stores traffic information obtained via the beacon receiver 5 or the FM multiplex receiving unit 6, Past traffic information is stored in the traffic information data memory 9. The navigation device body 1 detects the current position, azimuth, speed, and the like of the vehicle with high accuracy based on information obtained from the GPS receiver 4, the gyro 7, and the vehicle speed pulse detector 8. In addition, the navigation device body 1 is configured to change from the departure point specified by the user to the destination based on the map data stored in the CD-ROM 3 and the traffic information obtained through the beacon receiver 5 or the FM multiplex receiving unit 6. A route with the lowest cost is searched for as a guidance route, a map image near the current position of the vehicle is displayed on the monitor 2 using the map data stored in the CD-ROM 3, and a vehicle position mark and a guidance route are displayed. Is displayed in accordance with the map image, and various guidance information is provided to the user in accordance with the movement of the vehicle.

FIG. 2 is a schematic diagram showing a link. The link corresponds to a road between two adjacent intersections, and the road is represented as a set of a plurality of continuous links. Also,
Each link is provided with an individual link number (for example, L1 to L8) as shown in FIG. The traffic information transmitted via an optical beacon, a radio beacon, or FM multiplex broadcasting includes, for each link, a required time from the start point to the end point of the link (hereinafter referred to as travel time).

FIG. 3 is a diagram schematically showing a data storage area of the traffic information data memory 9. In the traffic information data memory 9, the data storage area is divided for each day of the week from Sunday to Saturday, and the data storage area for each day is changed to a data storage area for every 10 minutes from 0:00 to 23:50. I know. The data storage area for each hour is divided into two unit data storage areas for one link, an up route and a down route, and each unit data storage area stores the travel time of the link for the past four weeks. The average value can be stored. Further, a value (weight) indicating how many weeks the average travel time averages is also recorded in the memory 9. For example, when the travel time of the first to fourth weeks is a value shown in Table 1 below, the average travel time is calculated as shown in the table and updated every week.

[0018]

[Table 1]

In this way, as shown in FIG. 3, the average value of the link travel time is stored in the memory 9 as a kind of table (hereinafter, referred to as a table).
This table is referred to as a “link average travel time data table”). Hereinafter, the operation of the vehicle-mounted navigation device according to the present embodiment will be described. The car navigation device according to the present embodiment guides as follows according to whether or not traffic information from the outside can be received and whether or not the travel time from the departure point to the destination is equal to or less than a preset time. Find a route.

(1) If traffic information can be received and the travel time from the departure point to the destination is shorter than a predetermined time (for example, within one hour), the navigation device uses the traffic information data. The shortest route to the destination is searched for using the latest traffic information data input via an optical beacon, a radio beacon or FM multiplex broadcasting without using the link average travel time data table in the memory 9. . That is, if the travel time is within one hour, the degree of traffic congestion does not change significantly, so that the guidance route is searched using the latest traffic information.

(2) If traffic information can be received and the travel time from the departure point to the destination is longer than the predetermined time, the navigation device reaches the departure point to the destination in the predetermined time. A search is made for a guidance route to the point to be visited using the latest traffic information data, and for subsequent guidance routes using the link average travel time data table in the memory 9.

(3) When traffic information cannot be received, that is, where no beacon is installed or where FM broadcasts cannot be received, a guide route is searched using the link average travel time data table in the memory 9. I do.
Among the above, regarding the guidance route search method according to (2),
This will be described below. FIG. 4 is a diagram showing a road between the departure place ST and the destination DS, and FIG. 5 is a diagram showing a part of a link average travel time data table.

First, at 8:00 am on Sunday, destination D
It is assumed that the departure point ST departs for S. The navigation device receives the latest traffic information from the outside, and searches for a route using the traffic information. In this case, the departure point ST
From the starting point ST and the starting point ST and the destination point DS are alternately searched from the starting point ST and the destination point DS by the Dijkstra method. Time points PS1, PS
2. Calculate PS3 and PS4. That is, when the departure point ST departs at 8:00 am, these points PS1, P2
Arriving at S2, PS3 and PS4 at 9:00 am

Next, a route from each of the points PS1, PS2, PS3 and PS4 to the destination DS is searched. That is,
Find the expected time of arrival of the vehicle at the start of the link,
From the link average travel time data table, repeat the calculation to find the time to reach the end point of the link,
The expected time to reach the destination DS is obtained. For example, FIG.
, When calculating the route from PS1 to the destination DS, the estimated arrival time of PS1 is 9:00 am,
The scheduled time to reach the end point of the link Li starting from PS1 is 9:20 am from the link average travel time data table (see FIG. 5). Similarly, the link Li + 1
The scheduled time of arrival at the end of is 9:50 am.
In this way, the time at which the vehicle arrives at the destination DS from PS1 is calculated. Similarly, PS2, PS3, PS4
The average travel time read from the link average travel time data table is added along each route from to the destination DS, and the time to reach the destination DS is obtained for each route. Then, of these routes, the route with the shortest time is set as the guidance route. Since the link average travel time data table has only 10-minute data, the average travel time at an intermediate time (for example, 9:07 am) uses the average travel time at the time closest to that time. I do.

FIG. 6 is a flow chart showing the operation of the navigation system for on-vehicle use of this embodiment when searching for a guidance route. First, in step S1, it is checked whether or not traffic information can be received from outside. If the vehicle is out of the traffic information reception range (NO), step S
Proceeding to 2, the data of the same day of the week is read from the link average travel time data table in the memory 9 and a route with the shortest required time is searched. Then, this route is set as a guidance route.

On the other hand, if YES is determined in the step S1, the process proceeds to a step S3 to search for the shortest route to the destination by using the received traffic information. Then, the process proceeds to step S4. In step S4, it is checked whether there is a route that reaches the destination within one hour. If yes,
The process proceeds to step S5, and among the routes searched using the received traffic information, the shortest route is set as the guidance route.

If NO in step S4, step S4
Move to 6. Then, a route from the point reached in one hour to the destination is searched using the link average travel time data table stored in the memory 9 (see FIG. 4). After that, the process proceeds to step S7, and links that block or restrict traffic are extracted from the latest traffic information received by an optical beacon, a radio beacon, or FM multiplex broadcasting. Then, the process proceeds to step S8, and it is checked whether or not the closed route link is included in the route searched in step S6. If a closed road link is included (YES), the process proceeds to step S12, the cost of the closed road link is replaced with infinity, a new route is searched again, and step S8 is performed.
Return to

If NO in step S8, step S8
Then, the process proceeds to 9 to check whether or not the selected route includes a link that restricts traffic. In the case of NO, the searched route is set as a guidance route. If YES, step S1
The process proceeds to 0, and the travel time of the link whose traffic is being regulated is multiplied by a predetermined value to obtain the travel time of the link, and the required time to the destination is recalculated. Then, in step S11, the calculated required time is compared with the required time of another route to check whether or not the route is the shortest route. If yes,
The route is defined as a guidance route. If NO, step S
Then, the process proceeds to step 12 and a new route is searched again.

In the present embodiment, when the time required from the departure point to the destination is within one hour, guidance is performed using the latest link travel time acquired via the beacon receiver 5 or the FM reception unit 6. If the route is searched and the time required to reach the destination exceeds one hour, the guide route is searched using the past link travel time stored in the memory 9, so that the traffic congestion that will occur or the traffic congestion that will be resolved in the future And the time required to reach the destination can be calculated. As a result, a guidance route that reaches the destination in the shortest time can be obtained.

In the above embodiment, the case where the average value of the link travel time for four weeks is stored in the memory 9 has been described. However, the memory 9 may store the link travel time for one week. The average value of the link travel time for five weeks or more may be stored. Also,
In step 10 described above, the link travel time of the regulated link may use the link travel time obtained from the latest traffic information data.

Furthermore, the user may be able to appropriately select whether or not to use the link average travel time data table stored in the memory 9 when searching for a guide route.

[0032]

As described above, according to the present invention,
Since the past traffic information is stored in the past data storage means separately for each time, it is possible to calculate the cost in consideration of the traffic congestion to be generated or the traffic congestion to be resolved for each route,
The arrival time to the destination can be obtained more accurately. Thereby, there is an effect that a guidance route that can reach the destination in the shortest time is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a vehicle-mounted navigation device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing links.

FIG. 3 is a diagram schematically showing a data storage area of a traffic information data memory for storing past traffic information.

FIG. 4 is a diagram showing a road between a starting point ST and a destination point DS.

FIG. 5 is a diagram showing a part of a link average travel time data table.

FIG. 6 is a flowchart illustrating an operation of the vehicle-mounted navigation device according to the present embodiment when searching for a guidance route.

FIG. 7 is a diagram showing a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Navigation apparatus main body 2 Monitor 3 CD-ROM 4 GPS receiver 5 Beacon receiver 6 FM multiplex receiving unit 7 Gyro 8 Vehicle speed pulse detector 9 Memory

Claims (4)

[Claims] 1. An on-vehicle navigation device for searching for a guide route to a destination based on traffic information sent from the outside, comprising: a traffic information receiving means for receiving the traffic information; Searching for the guidance route using the past traffic information stored in the past data storage means and the latest traffic information obtained through the traffic information receiving means. An in-vehicle navigation device comprising a guidance route searching means. 2. The in-vehicle navigation device according to claim 1, wherein the past data storage unit stores the past traffic information for at least one week separately for each day of the week. 3. The in-vehicle navigation device according to claim 1, wherein the past data storage unit stores an average value of the past traffic information for two weeks or more for each day of the week. 4. The guide route searching means calculates a required time to the destination based on the latest traffic information received via the traffic information receiving means, and the required time is a predetermined time. If the time exceeds the predetermined time, a search is made for a guidance route traveling within the predetermined time based on the latest traffic information, and the guidance route for the time exceeding the predetermined time is stored in the past data storage unit. The in-vehicle navigation device according to any one of claims 1 to 3, wherein the search is performed using the traffic information of (1).