JP3293375B2 - Car navigation system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a car navigation system having a traveling route guidance function.

[0002]

2. Description of the Related Art
Road map information composed of nodes representing the characteristic positions of roads, such as intersections on roads and entrances and exits of elevated roads, links connecting the nodes to complete the roads, and virtual nodes set in the links By specifying a departure point and a destination point, a node closest to each specified point is selected from the nodes and the virtual nodes, and an optimal traveling route is determined from a route connecting these points. A car navigation device having a traveling route guidance function for guiding a passenger is known.

However, such road map information is usually stored only as two-dimensional position information, and there is no distinction between elevated roads and ordinary roads. Thus, for example, as shown in FIG. 12 (A), when specifying the destination point Xe and have you in such regions existing near the the elevated road and general road, as shown in the drawing (B), Virtual node n101 of the elevated road is selected as the closest one,
In some cases, a traveling route R1 that ends on an elevated road may be guided. For this reason, it is impossible to provide correct route guidance (the traveling route R2 leading to the node N101 in FIG. 9C).

[0004] The starting point Xs is also shown in FIG.
As shown in (A), when an elevated road and a general road are close to each other, a node or a virtual node on the elevated road is selected in spite of an attempt to depart from a parking lot under the elevated road. There is a risk. In this case, an incorrect traveling route R3 (illustration (B)) is guided instead of the correct traveling route R4 (illustration (C)).

When a general road and an elevated road are overlapped with each other, the detection signal of a gradient sensor mounted on the vehicle is integrated to detect the altitude, and only the elevated or ordinary road is displayed. 2. Description of the Related Art A car navigation device is known (Japanese Patent Application Laid-Open No. 1-134029). However, this technique merely switches the map display, and does not provide guidance on a traveling route from a departure point to a destination point.

[0006] In order to provide guidance on a traveling route, the current position is not always set as the departure point. Also, with such a technology, even if it is incorrectly determined that the vehicle is traveling on an elevated road despite being traveling on an ordinary road, and such a map is displayed, the general road and the elevated road are rarely overlapped forever. In any case, the display is naturally switched to the display of traveling on a general road from the relationship with the vehicle position detection result.

[0007] However, when providing a traveling route, all of them are determined when the departure point and the destination point are designated. Therefore, if the departure point is selected on the wrong road, the traveling route itself will be lost. There is a problem of being wrong.
Furthermore, the above-mentioned conventional technology cannot be applied at all as a technology for correctly selecting a target point.

Accordingly, an object of the present invention is to provide a car navigation device capable of setting a correct departure point and a destination point from a three-dimensional road and correctly guiding a traveling route.

[0009]

The car navigation system of the present invention completes a road by connecting nodes representing characteristic positions of the road, such as intersections on roads and entrances and exits of elevated roads, and connecting the nodes. Map information storage means for storing road map information composed of links for linking and virtual nodes set in the link, point designating means for designating a departure point and a destination point, the node and the virtual node A node selecting means for selecting a point closest to each point specified by the point specifying means, and a travel route from a departure point to a destination point based on the selection result and the road map information. In a car navigation apparatus provided with traveling route guidance means for guiding, a node which cannot be selected by the node selecting means in performing the traveling route guidance. And a non-selectable node determining unit for determining a virtual node, wherein the node selecting unit is configured to perform the selection from a node other than the determined node and the virtual node and a virtual node. Features.

The nodes are not limited to "intersections" and "entrances to elevated roads", but also "road junctions and junctions", "tunnel entrances", "bridge entrances" and "long lasting without junctions". A point on the way of the road on which the vehicle passes, or a start point and an end point of an underpass or an overpass.

According to the car navigation system of the present invention, when selecting a departure point and a destination point for guiding a traveling route, not all nodes and virtual nodes are targeted, but the departure point and the destination. Only the remaining nodes and virtual nodes excluding the nodes and virtual nodes that cannot be selected as are targeted. Therefore, the traveling route is not determined based on the wrong departure place or destination.

Specifically, in the present invention, an attribute of each link is stored as the road map information, and the non-selectable node determining means determines a node and a virtual node which cannot be selected based on the attribute. I did . Then, the attribute, Ru is configured as information for distinguishing the positional relationship in the height direction of each link relative to the ground. As a result, "elevated roads" and "overpasses" that are high with respect to the ground, "tunnels" and "underpasses" that are low with respect to the ground
And the like can be determined, and it is possible to prevent a virtual node at such a location from being set as a target point.

Alternatively, the present invention may be realized as an invention in which the attribute is constituted as information for distinguishing whether or not the road is a road on which a vehicle cannot be parked or stopped. It is impossible to set the destination on a road that cannot be parked or stopped, and since the operation for providing such a travel route guidance is usually performed while the vehicle is parked or stopped, the operation on the road that cannot be parked or stopped is performed. This is to avoid using a node or virtual node as a departure point or a destination. Tunnels, elevated roads, and the like are excluded as non-selectable nodes not only from the viewpoint of height but also from the viewpoint of whether parking or stopping is possible.

Roads that cannot be parked or stopped include "bridges", "elevated roads", "tunnels", and the like.
Attributes such as "Rotary", "Interchange", "Junction", etc. can also be given, and attributes may be given based on "No-parking zone" or "No-parking zone" in the Road Traffic Act. .

[0015]

[0016]

[0017]

[0018]

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. As shown in FIG. 1, a car navigation device 10 according to a first embodiment includes a microcomputer 11, a display 12 for displaying a map, and an operation key switch 1 for input.
3. CD-ROM device 14, G storing road map information
It comprises a GPS position detecting device 15 for receiving a signal from a PS satellite to detect the current position of the vehicle, a gyro 16 for detecting the traveling direction of the vehicle, a vehicle speed sensor 17, and the like. In this embodiment, the operation key device 13 is configured to be operable only when the vehicle is stopped.

As shown in FIG. 2B, the road map information includes, as shown in FIG. 2B, nodes Nn and Nn which represent characteristic positions of the road such as intersections on roads and entrances and exits of elevated roads. , A link Ln for connecting the nodes Nn to complete a road, and a virtual node nn set in the link Ln (n = 1, 2,...). Then, as shown in FIG. 3C, an attribute “0” or “1” indicating whether or not the link Ln can be selected as a departure point and a destination point is given in a traveling route guidance control process described later. ing. In this embodiment, the attribute “0” indicating that the link at a position higher or lower than the ground such as “elevated”, “underpass”, “tunnel”, “overpass”, and “underpass” cannot be selected has The attribute “1” indicating that the link is selectable is given to links of other general roads on the ground surface. In addition to the above attributes, attributes necessary for the traveling route determination processing, such as the type of road such as a national road, a prefectural road, and an agricultural road, information on the width of the road, and information on whether or not the road is a toll road, are also given.

As shown in FIG. 3, the road map information as the route data is hierarchically set in multiple stages such as a detailed network, a basic network, and a wide area network. This is because a detailed network is used to designate a departure point and a destination point, and a basic network and a wide area network are used to connect the departure point and the destination point. In this embodiment, the wide area network is configured as a road map based on main roads such as major national roads and expressways, the basic network is configured as a road map including major prefectural roads, and the detailed network is configured as a road map including substantially all public roads. ing.

The car navigation device 10 of the present embodiment is configured to detect the position of the vehicle by a system as shown in FIG. Dead reckoning and map matching are used together to detect the position of the vehicle.
Dead reckoning is executed based on the detection results by the GPS position detecting device 15, the gyro 16, and the vehicle speed sensor 17. Schematically, the GPS position detecting device 15 captures the latitude / longitude information of the own vehicle, thereby grasping the absolute position, and calculating the relative movement trajectory of the own vehicle by the gyro 16 and the vehicle speed sensor 17 to obtain the current position. It estimates the position of the vehicle. The map matching is a method in which the estimated movement locus is added to the shape of the road to correct the deviation as if the vehicle were just on the road. By using these dead reckoning navigation and map matching together, it is possible to always display the own vehicle at a considerably accurate position without deviating from the road.

Next, the processing contents of the traveling route guidance control will be described with reference to the flowcharts shown in FIG. In this process, the driver operates the operation key device 13 in a stopped vehicle.
Is started by designating the traveling route guidance process from.

First, the current position of the vehicle as a result of dead reckoning and map matching is taken in as a starting point (S10). Next, a menu screen for inputting the destination point is displayed (S20). Then, the destination is captured according to the selected menu (S
30). In this embodiment, the place name index list is displayed, and the “index method” is selected from the list.
Basic map-> wide area map-> basic map-> detailed map-> change the map to a detailed map, select a detailed map of the destination, and specify an arbitrary point in the detailed map, a "close-up method", a nearby destination It is configured so that it can be selected from "cursor movement method" suitable for designation. Note that the fine map is a map that includes more detailed information than the detailed map. As shown in FIG. 3, the route data has only a detailed map, but the departure point and the destination have a finer map.

When the departure point and the destination point have been captured in this way, first, a departure point node selection process (S40) is executed, subsequently, a destination node selection process (S50) is executed, and thereafter, a travel route determination process (S40) (S60), the driving route guidance process (S70) is executed, and the process exits from this routine.

Here, the traveling route determination processing (S60)
Based on the link attributes such as road type, width, and whether or not the road is a toll road, scores are given from several viewpoints among the possible routes between the departure node and the destination node. This is a process for determining which route to guide to. For example, a toll road or a toll road, such as a route with a shorter distance increases the selectivity, a wider road increases the selectivity, a national road → a prefectural road →… A traveling route to be guided is determined by synthesizing a plurality of conditions such as increasing the selectivity according to one of the free roads.

The traveling route guidance process (S70) is a process for displaying the traveling route to the destination determined in this way by changing the color on a map, and guiding the driver to the route.
At intersections and junctions, go straight, turn right, turn left
Such information may be guided together with voice or the like.

Next, details of the departure point node selection processing (S40) will be described with reference to FIG. In this process, first, it is determined whether or not link data that has not been considered exists in the detailed map data including the departure point (S100). At first, since there is link data that has not been considered, the process of reading one link data (S1)
Go to 10). Then, it is determined whether or not the attribute indicating whether the read link data can be selected is “1” (S12).
0). If “0”, the process returns to S100. On the other hand, if the attribute is “1”, the distance between the virtual node in the link data and the nodes corresponding to both ends of the link is calculated from the point taken as the starting point (S130). Then, a node or a virtual node having the shortest distance is selected and set as a temporary provisional node this time (S140). Then, it is determined whether or not the distance dnow from the temporary recommended node to the departure point is shorter than the distance dold from the previous recommended node to the departure point (S
150). If dnow <dold, the tentative recommended node is set as a recommended node (S160), otherwise, the recommended node is left as it is (S170).

When a recommended node is selected in this way, S
Return to 100. Then, when the processing of S110 to S170 is completed for all the links in the detailed map data, the recommended node at that time is selected as the departure point node (S180). As shown in FIG. 7, the destination node selection processing (S50) is configured in exactly the same way as the departure node selection processing. Each step is represented in the 200s, and detailed description is omitted.

As described above, according to the present embodiment, “elevated”
A departure point node and a destination node are not selected from links that are higher or lower than the ground, such as “underpass”, “tunnel”, “overpass”, and “underpass”. Therefore, an inappropriate traveling route guidance as shown in FIGS. 12 (B) and 13 (B) does not occur, and an appropriate traveling route as shown in FIGS. 12 (C) and 13 (C). Guidance can be provided.

Next, a second embodiment will be described. As shown in FIG. 8, the car navigation device 20 of the second embodiment
The hardware configuration is the same as the configuration of the first embodiment described above except that a gradient sensor 21 is added. Then, as shown in the traveling position determination processing routine of FIG. 9, when the vehicle passes through the portion of the entrance node to the elevated road, the gradient sensor 2
1 (S300, S310), and if it indicates an ascending gradient, it is on an elevated road (S320, S3).
30) If it indicates a descending gradient, it is determined that the vehicle is on a general road (S340, S350), otherwise, it is determined that the road has not changed (S360).
Therefore, in S360, once it is determined that the vehicle has risen onto the elevated road, it is determined that the vehicle is still on the elevated road.

As the road map information, attribute information indicating whether each link is on an elevated road or not is given. “0” is assigned to an object on an elevated road, and “1” is assigned to an object that is not. The main routine of the traveling route guidance control is the same as that of FIG. 5, but the processing of the procedure shown in FIGS. 10 and 11 is employed as the departure point node determination processing therein.

In this process, first, it is determined whether or not the currently determined traveling position is on an elevated road (S40).
0). And if it is determined that it is on an elevated road,
It is determined whether link data that has not been examined among the link data having the attribute “0” exists in the detailed map data including the departure point (S410). At first, since there is link data that has not been considered, the process proceeds to the process of reading one link data (S420). And
For all the virtual nodes in the link data and the nodes corresponding to both ends of the link, the distance from the point taken as the starting point is calculated (S430), and the node or virtual node with the shortest distance is selected. Is set as the current tentative recommendation node (S440), and thereafter, similar to S150 to S170 of the first embodiment, the closer one is set as the recommended node and the process returns to S410 (S450 to S470).

On the other hand, if it is determined that the currently determined traveling position is not on an elevated road, among the link data having the attribute “1”, the link data which has not been examined is the detailed map data including the starting point. It is determined whether or not it exists inside (S510). Until all link data has been examined, the same processing as in S420 to S470 is repeated to determine recommended nodes (S520 to S57).
0).

When it is determined in S410 or S510 that all the examinations have been completed, the recommendation node at that time is selected as the departure node (S600). The destination node selection process is the same as in the first embodiment. This second
According to the embodiment, similarly to the first embodiment, a common point is that a node or a virtual node that cannot be selected is not selected as a departure node or a destination node. Further, even when the departure position is on an elevated area such as a service area of a highway, the use value is further enhanced in that a traveling route can be definitely selected.

Although the embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and can take various forms. For example, when the link attribute is included in a parking prohibited area or a parking prohibited area according to the Road Traffic Law, it may be set so that it cannot be selected as a departure or destination node. These links include highways, tunnels, bridges, and roundabouts. In addition, an attribute may be given as an unselectable link as a departure place or a destination at an interchange or a junction.

In the second embodiment, an elevated road can be specified only for the departure point. However, for example, as in a case where a service area is a destination, an elevated road can be selected as a destination. For example, if the user inputs that fact from the operation keys, the destination node may be selected only on the elevated road.

Further, the departure point may be manually input by a close-up method or a cursor method as in the case of the destination point.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a car navigation device according to a first embodiment.

FIG. 2 is an explanatory diagram illustrating a configuration of road map information according to the first embodiment.

FIG. 3 is an explanatory diagram showing a configuration of road map information in the first embodiment.

FIG. 4 is an explanatory diagram of a vehicle position detection method according to the first embodiment.

FIG. 5 is a flowchart of a traveling route guidance control process in the first embodiment.

FIG. 6 is a flowchart of a departure point node selection process in the first embodiment.

FIG. 7 is a flowchart of a destination node selection process in the first embodiment.

FIG. 8 is an overall configuration diagram of a car navigation device according to a second embodiment.

FIG. 9 is a flowchart of a traveling position determination process in the second embodiment.

FIG. 10 is a flowchart of a departure point node selection process in the second embodiment.

FIG. 11 is a flowchart of a departure point node selection process in the second embodiment.

FIG. 12 is an explanatory diagram showing a conventional problem.

FIG. 13 is an explanatory diagram showing a conventional problem.

[Explanation of symbols]

10 ... car navigation device, 11 ... microcomputer, 12 ... display, 13 ...
Operation key device, 14 ... CD-ROM device, 15 ...
・ GPS position detecting device, 16 ・ ・ ・ Gyro, 17 ・ ・
・ Vehicle speed sensor, 20 ・ ・ ・ Car navigation device, 2
1 ... gradient sensor, Ln ... link, Nn ... node, nn ... virtual node, Xe ... destination point, X
s ... Departure point.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G01C 21/00 G08G 1/0969 G09B 29/00-29/10

Claims (2)

(57) [Claims] 1. A node that represents a characteristic position of a road such as an intersection on a road or an entrance of an elevated road, a link connecting the nodes to complete the road, and a virtual node set in the link. Road map information storage means for storing road map information to be executed, a point designation means for designating a departure point and a destination point, and, among the nodes and the virtual nodes, closest to each point designated by the point designation means A car navigation device comprising: a node selecting means for selecting an object; and a traveling route guiding means for determining and guiding a traveling route from a departure point to a destination point based on the selection result and the road map information. Height of each link with respect to the ground as road map information
It is configured as information to distinguish the positional relationship in the direction.
The attribute of each link is stored, and the nodes and virtual nodes that cannot be selected by the node selecting means in performing the travel route guidance are stored in the attribute.
The node selection means is configured to perform the selection from nodes and virtual nodes other than the determined node and the virtual node. Car navigation device. 2. Intersections on roads and entrances and exits of elevated roads
Nodes that represent the characteristic positions of roads
Link to complete the road with
Road map information composed of virtual nodes
Road map information storage means, point designation means for designating a departure point and a destination point, and the point designation means from among the nodes and the virtual nodes.
Node selection to select the closest one to each point specified by
Means and a starting point based on the selection result and the road map information.
A travel route that guides the user by searching for a travel route from the destination to the destination
In the car navigation device provided with a guide means , the road map information is used for parking or stopping a vehicle.
Information to distinguish whether or not the road is impossible
The attribute of each link configured is stored, and the node selection means is used in performing the travel route guidance.
The nodes and virtual nodes that cannot be selected by the attribute
Comprising a selection disable node determining means for determining based on said node selection means, the determination node and virtual
Selection from among nodes other than nodes and virtual nodes
Car navigation system configured to perform
Gating device.