JP3155120B2 - Navigation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device mounted on a moving body such as a vehicle and presenting an optimum route to a destination to an occupant of the moving body.

[0002]

2. Description of the Related Art A navigation apparatus presents an optimum route to a destination when a moving object moves.
As a presentation of the optimal route to the destination, for example,
There is one described in Japanese Patent Application Laid-Open No. 1-118998. The publication describes that a combination of road segments that can reach a destination (hereinafter, this combination is referred to as a route set) is obtained based on map information stored in a storage device, and then the storage device The required time for each set of routes is calculated from the required time corresponding to each road segment stored in the section, and the route set corresponding to the shortest time is determined as the optimum route.

According to such a method for determining an optimum route,
Since it is necessary to search for all the road segments constituting the road network, if the distance to the destination is long, the number of road segments to be evaluated increases geometrically. Therefore, there is a disadvantage that the calculation time until the optimum route is obtained increases exponentially. Several methods have been established as route search methods, such as the Dijkstra method and the A ^* method.
However, the calculation time exponentially increases with each method, although the degree varies.

It is convenient for the occupant if information on the optimum route can be obtained at least partially in advance, but the optimum route is determined only after the required time has been calculated for all the determined route sets. Absent.

[0005] To solve such a disadvantage, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 4-204482. FIG. 47 is a block diagram showing the configuration of the navigation device described in that publication. In the figure, 47
1 is a current position detecting means for detecting the current position of the vehicle, 47
Reference numeral 2 denotes an operation device that receives an operation input by the occupant, and 473 indicates, for each representative point in a predetermined area, an optimal route between the arbitrary representative point as a departure point and another arbitrary representative point as a destination. A representative point-to-point route data memory that stores a representative point-to-point table in which identification numbers shown are described, and a route table in which each node and each link constituting an optimum route corresponding to each identification number are described.

Reference numeral 474 is a map data memory storing map information, 475 is a representative point route search means for finding an optimal route between representative points using the contents of the representative point route data memory 473, and 476 is a departure point to a destination. Route search means 477 for searching for the optimum route up to is a display for displaying the optimum route and the like.

Next, the operation will be described. When a destination is input from the operating device 472, the representative point route searching means 475 searches the map data memory 474 for a representative point closest to the destination. Further, a representative point closest to the current position input from the current position detection means 471 is searched from the map data memory 474. Then, the optimum route between the two representative points is searched from the route data memory 473 between the representative points.

Next, the route search means 476 determines the optimum route between the representative point closest to the current position and the current position by using the contents of the map data memory 474. Also, the best route between the representative point closest to the destination and the destination,
It is determined using the contents of the map data memory 474. Then, the optimal route and the representative point route searching means 4
The route connecting the optimal routes determined by the unit 75 is set as the optimal route from the current position to the destination, and the route is displayed on the display 477.

[0009]

Since the conventional navigation device is configured as described above, Japanese Patent Laid-Open Publication No.
In the method described in Japanese Patent Application Laid-Open No. 19898, in which the optimum route is obtained each time a passenger requests, when the distance to the destination becomes longer, the calculation time until the optimum route is obtained becomes an exponential function. Increase. In addition, the occupant must wait until the calculation processing of the navigation device is completed.
There is also a problem that information on the optimal route cannot be obtained at all. In Japanese Patent Application Laid-Open No. 4-204482, such a problem is solved, but since the optimal route to the destination specified by the occupant is calculated, the representative point closest to the destination is calculated. It takes time to calculate the optimal route between the destination and the destination. Furthermore, since the possible combinations of the representative points are set as the departure point and the destination, and all the route data for each of them is used as the representative point-to-point route data, it is unnecessarily necessary to increase the density of representative point selection. There is a disadvantage that the amount of memory increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an optimum route to a destination can be quickly calculated from an arbitrary road branch point in a road network as a departure point. It is an object of the present invention to obtain a navigation device whose quantity falls within a practical range.

[0011]

According to a first aspect of the present invention, there is provided a navigation apparatus for generating map information including information on each road junction and information on a road segment connecting the road junctions, and a route calculation target area. Map information storage means having area index information indicating the degree of reach of each road segment to each of the plurality of divided areas to be constituted, point setting means for setting a departure point and a destination, and point setting means. The road junction near the departure point is determined using the map information in the map information storage means, and the divided area including the destination set by the point setting means is determined as the destination area, and the road near the departure point is determined. An optimum route calculating means for calculating an optimum route from the branch point to the destination area by using each reachability in the area index information in the map information storage means; It is obtained by a route information presenting means for presenting the optimum route road calculation means has calculated.

According to a second aspect of the present invention, there is provided a navigation apparatus comprising: map information including information on each road junction and information on a road segment connecting the road junctions; and a plurality of areas constituting a route calculation target area. Map information storage means having area index information indicating the degree of reach of each road segment to each of the divided areas where adjacent areas have overlapping portions; point setting means for setting a departure place and a destination; The road branch point near the departure point set by the setting means is determined using the map information in the map information storage means, and one of the divided areas including the destination set by the point setting means is determined. Optimal route that is determined as the destination area and calculates the optimal route from the road junction near the departure point to the destination area using each ease of arrival in the regional index information A calculation unit, in which a route information presenting means for presenting the optimum route the optimal path calculation means has calculated.

According to a third aspect of the present invention, there is provided a navigation device, comprising: map information including information on each road junction and information on a road segment connecting the road junctions; and a plurality of wide area divisions constituting a route calculation target area. An area indicating the accessibility of each road segment connected to each road junction to each of the regions and the accessibility of each road segment to each of the narrow subdivisions forming the wide area division including the road junction. Map information storage means having index information;
Point setting means for setting a departure point and a destination, and a road branch point near the departure point set by the point setting means are determined using the map information in the map information storage means and set by the point setting means. Is determined as the destination area, and the optimal route from the road junction near the departure point to the destination area is calculated using each ease of arrival in the area index information in the map information storage means. When the optimal route reaches the destination area, the optimal route calculation that calculates the optimal route to the destination area by using the ease of arrival in the regional index information by setting the narrow divided area including the destination as a new destination area And route information presenting means for presenting the entire optimal route calculated by the optimal route calculating means.

According to a fourth aspect of the present invention, there is provided a navigation device comprising: map information including information on each road junction and information on a road segment connecting the road junctions; and a plurality of areas constituting a route calculation target area. Map information storage means having area index information indicating the degree of reach of each road segment to each of the divided areas corresponding to the administrative division areas; point setting means for setting a starting point and a destination; and point setting means The road branch point near the departure point set by the method is determined using the map information in the map information storage means, and the divided area including the destination set by the point setting means is determined as the destination area. Route calculator that calculates the optimal route from the road fork near the road to the destination area using each reachability in the regional index information in the map information storage means Means, in which a route information presenting means for presenting the optimum route optimal path calculation means has calculated.

According to a fifth aspect of the present invention, there is provided a navigation apparatus comprising: map information including information on each road junction and information on a road segment connecting the road junctions; and a plurality of divided areas constituting a route calculation target area. Map information storage means having area index information indicating the degree of reach of each road segment connected to each of the main roads, a point setting means for setting a starting point and a destination, and a point setting means. The road branch point of the main road near the departure point is determined using the map information in the map information storage means, and the divided area including the destination set by the point setting means is determined as the destination area. An optimal route calculating means for calculating an optimal route from a road branch point of a nearby main road to a destination area using each reachability in the area index information; It is obtained by a route information presenting means for presenting the optimum route road calculation means has calculated.

According to a sixth aspect of the present invention, there is provided a navigation apparatus comprising: map information including information on each road junction and information on a road segment connecting the road junctions; Map information storage means having area index information indicating the degree of reach, point setting means for setting a departure place and a destination arterial road, and map information storage means for storing road branch points near the departure place set by the point setting means Route calculation means for determining using the map information in the area and calculating the optimum route from the road branch point near the departure point to the target arterial road using the respective degrees of reach in the regional index information; and Route information presenting means for presenting the optimum route calculated by the calculating means.

According to a seventh aspect of the present invention, there is provided a navigation device, comprising: map information including information on each road junction and information on a road segment connecting the road junctions; and a plurality of divided areas constituting a route calculation target area. , Map information storage means having area index information indicating the degree of reach of each road segment to each of the above, point setting means for setting a departure place and a destination, and roads near the departure place set by the point setting means The branch point is determined using the map information in the map information storage means, the divided area including the destination set by the point setting means is determined as the destination area, and the road branch point near the departure point is determined as the destination area. The optimum route to the neighborhood is calculated using each degree of reach in the area index information in the map information storage means, and the vicinity of the destination area is calculated from the vicinity of the destination area. And optimal route calculation means for obtaining the graph search processing an optimum route in, in which a route information presenting means for presenting the whole of the optimum route according to the optimal path calculation means.

According to an eighth aspect of the present invention, there is provided the navigation device according to the first or sixth aspect, further comprising a traffic information receiving device for receiving real-time traffic information, wherein the optimal route calculating means calculates the calculated real-time traffic information. A part of the optimum route within a range where the real-time traffic information is effective is replaced with an optimum route by a graph search process in which the real-time traffic information received by the traffic information receiving device is added.

According to a ninth aspect of the present invention, there is provided a navigation device, comprising: information on each road junction; information on a road segment connecting the road junctions; and each divided region forming each road junction and a route calculation target area. Map information storage means having map information including correspondence information on the correspondence relationship with the map, and area index information indicating the degree of accessibility of each road segment to each of the divided areas, and a point setting means for setting a departure place and a destination And a road junction near the departure point set by the point setting means is determined using the map information in the map information storage means, and the divided area including the destination set by the point setting means is set as the destination area. Determine the optimal route from the road junction near the departure point to the destination area, the corresponding information in the map information in the map information storage means and the area index information And optimal route calculation means for calculating with the arrival easiness of, in which a route information presenting means for presenting the optimum route optimal path calculation means has calculated.

According to a tenth aspect of the present invention, there is provided a navigation device, comprising: map information including information on each road junction and information on a road segment connecting the road junctions;
Map information storage means having local index information indicating the degree of reach of each road segment or the degree of reach to each road to each of the plurality of divided areas constituting the route calculation target area; A point setting means for setting a destination area or a destination road, which is one of them, and a road fork near a departure point set by the point setting means are determined using map information in a map information storage means. Optimum route calculation for calculating an optimal route from a road branch point near the departure point to a destination area or a destination road set by the point setting means by using each reachability in the area index information in the map information storage means. Means and route information presenting means for presenting the optimum route calculated by the optimum route calculating means.

[0021] The navigation device according to the eleventh aspect of the present invention is a navigation device, comprising: map information including information on each road junction and information on a road segment connecting the road junctions;
Map information storage means having area index information indicating the degree of reach of each road segment to each of the representative points in a plurality of divided areas constituting the route calculation target area; and point setting means for setting a departure place and a destination And determining a road fork near the departure point set by the point setting means using the map information in the map information storage means,
The representative point of the divided area including the destination set by the point setting means is determined as the destination representative point, and the optimal route from the road branch point near the departure point to the destination representative point is determined by the area index information in the map information storage means. An optimal route calculating means for calculating using each of the eases of reaching the route, and a route information presenting means for presenting the optimal route calculated by the optimal route calculating means.

The navigation apparatus according to the twelfth aspect of the present invention has map information including information on each road junction and information on a road segment connecting the road junctions, and also calculates a route calculation target area. Map information storage means having area index information in which the degree of accessibility of each road segment to each of the plurality of divided areas is set according to the direction of approach to each road junction; A point setting means for setting a place, and a road fork near a departure point set by the point setting means is determined using map information in a map information storage means, and a destination set by the point setting means is determined. Is determined as the destination area, and the optimum route from the road junction near the departure point to the destination area is determined by the entry direction pair in the area index information in the map information storage means. And optimal route calculation means for calculating with the arrival easiness of, in which a route information presenting means for presenting the optimum route optimal path calculation means has calculated.

[0023]

According to the first aspect of the present invention, the optimum route calculating means corresponds to a road branch point, using a road branch point closest to the departure point as a starting point and a predetermined area including the destination as a destination area. Then, the degree of reach in the area index information provided is sequentially evaluated, and road sections optimal for heading to the destination area are sequentially determined.

In the present invention, a plurality of divided areas including a certain road branch point are generally defined. The optimal route calculation means selects an optimal destination area according to a positional relationship between the departure point and the destination, or a path calculation condition such as toll road priority or toll road avoidance, and determines an optimal route to the selected destination area. calculate.

According to the third aspect of the present invention, the area index information in the map information storage means is broad area index information covering a wide area by coarse division, and narrow area index information covering the vicinity of a road junction by dense division. And information. Therefore, a wide area for route calculation is covered by the area index information having a small amount of data. First, the optimal route calculation means
The road segment that constitutes the optimal route is determined using the divided area obtained by the coarse division, and when the route tip approaches the destination,
The optimal route is calculated using the divided area by dense division.

According to the fourth aspect of the present invention, the divided areas are configured so as to coincide with or substantially coincide with the administrative boundaries, so that an evenly divided area is realized. In other words, if the area is divided based on a simple geometrical figure, it is highly likely that the area with high road density will be divided. Divided by location. By such division, the optimum route calculation means can calculate a route that is appropriate even near the end point of the route.

Since only the map information and the area index information relating to the main route are set in the map information storage means in the fifth aspect of the present invention, the memory size is small. For a long-distance route, the ratio of the main road to the route is large. Therefore, even if only the regional index information on the main road is used, the optimum route calculating means calculates a sufficiently appropriate route. Alternatively, the route from the road branch point near the departure point to the road branch point of the main route near the departure point may be obtained by a graph search between two points.

[0028] The optimum route calculating means in the invention according to claim 6 evaluates the main road index information describing the degree of ease of reaching from the road branch point on the non-main road to the nearby main road. The road segments on the route are determined.
Therefore, the optimal route to the main road can be calculated quickly.

The optimum route calculating means in the invention according to claim 7 determines the end portion of the route by a graph search between two points. Therefore, it is possible to quickly calculate the divided area near the destination, shorten the time required for the route calculation as a whole, and create detailed information about the part near the destination.

[0030] The optimum route calculation means in the invention according to claim 8 limits the applicable range of traffic information that changes in real time such as traffic congestion to an effective range. Then, the traffic information applicable range of the optimum route obtained using the regional index information or the main road index information is replaced with a route obtained by a graph search between two points in consideration of real-time traffic information. Therefore, it is possible to calculate a more appropriate route using the real-time traffic information while ensuring the high speed of the route calculation using the index information.

In the map information storage means according to the ninth aspect of the present invention, information for identifying a divided area to which the road branch point belongs is added to the road branch point information. Therefore, when determining whether or not a certain road branch point belongs to the destination area, the optimum route calculation means can perform the determination without performing complicated area inclusion processing.

According to the tenth aspect of the present invention, the point setting means directly accepts an area or a road as a destination and supplies the destination to the optimum route calculating means. Therefore, the point setting means simplifies the operation of the occupant when setting the destination.

[0033] In the map information storage means according to the eleventh aspect, the degree of ease of reaching the representative point of the divided area is set as area index information. Therefore, the optimum route calculation means can calculate the optimum route to the representative point in the destination area.

In the map information storage means according to the twelfth aspect, area index information corresponding to the approach direction of each road junction is set. Therefore, the optimal route calculation means
It is possible to calculate the optimum route in consideration of the traffic regulation of each road junction and each road segment.

[0035]

【Example】

Embodiment 1 FIG. FIG. 1 is a block diagram showing a configuration of a navigation device according to one embodiment of the present invention. In the figure,
A map information storage means 1 has at least information on each road junction (road junction information), information on a road segment connecting two junctions (road segment information), and local index information corresponding to each road junction. 2 is a current position detecting means for detecting the current position of the moving body, 3 is a point input means for inputting a departure place and a destination, and 4 is an optimal means for determining an optimum route between the departure place and the destination. The route calculating means 5 is a route information presenting means for presenting the optimum route determined by the optimum route calculating means 4 to the occupant together with the map information and the current position information. The point setting means is realized by the current position detecting means 2 or the point input means 3.

The map information storage means 1 can be realized by a computer peripheral storage device such as a semiconductor memory device, a CD-ROM device, and a hard disk device. Further, the present position detecting means 2 can be realized by using a speed sensor and a geomagnetic sensor or a gyro sensor. In other words, the speed data obtained by integrating the speed data from the speed sensor in a vector manner using the traveling direction of the moving object by the geomagnetic sensor or the gyro sensor and detecting the current position as a relative displacement from the initial position can be applied. Alternatively, a device that detects the absolute position of a moving object by using a radio signal from a GPS (Global Positioning System) can be applied. Further, a method is often used in which the current position and orientation determined using various sensor signals are corrected by collating with a detailed road network database.

The point input means 3 is realized by a display unit such as a CRT or a liquid crystal, an input unit, and a control unit for controlling them. FIG. 2 is a configuration diagram showing an example of the configuration of the point input means 3. In the figure, reference numeral 21 denotes a display unit such as a CRT or a liquid crystal;
2 is a scroll switch for moving the map displayed on the display unit 21, 23 is an enlargement switch for enlarging the display content, 24 is a reduction switch for reducing the display content, and 25 is a departure place. Is a destination switch for setting a destination. 27 indicates a map displayed on the display device 21;
28 indicates a cursor.

The control unit (not shown) displays the map 2 on the display unit 21 in accordance with the map information read from the map information storage means 1.
7 is displayed. At the same time, the cursor 28 is displayed. When the occupant operates the scroll switch 22, the control unit moves the map in the display unit 21. Therefore, the occupant can display a desired area on the display unit 21 by using the scroll switch 22.

To enter the departure point, the occupant presses the departure point switch 25 when the position of the departure point matches the position of the cursor. Then, the control unit calculates the latitude and longitude of the position of the cursor at that time, and sets the position indicated by them as the starting point. Similarly, a destination is set using the scroll switch 22 and the destination switch 26. When the enlargement switch 23 is pressed at the time of setting the departure place or the destination, the control unit enlarges and displays the map.
When the reduction switch 24 is pressed, the map is reduced and displayed. With this function, the occupant can accurately specify the point.

The structure of the point input means 3 is not limited to the structure shown in FIG. Since various other methods for specifying an arbitrary point on the map are known, a configuration using any one of these methods may be adopted. For example, there is a method in which each point name and its representative coordinate position are stored as map information, a point list is displayed on a screen, and a departure point and a destination are selected from the list. Further, the current position by the current position detecting means 2 may be used as the departure place.

The route information presentation means 5 is realized by a display unit such as a CRT or a liquid crystal, an input unit, and a control unit. FIG. 3 is a configuration diagram showing an example of the configuration of the route information presentation means 5. The control unit (not shown) displays the map 27 on the display unit 21 according to the map information read from the map information storage unit 1. Further, a current position symbol 31 is displayed on the map at a position corresponding to the detection result of the current position detecting means 2. Further, a route symbol 32 indicating the optimum route determined by the optimum route calculation means 4 is displayed.

The occupant can move the map with the scroll switch 22, and can enlarge or reduce the map with the enlargement switch or the reduction switch. Further, the scroll switch 22, the enlargement switch 23, and the reduction switch 24 can be shared with the point input means 3. In addition, although the case where the display unit 21 is shared with the one in the point input unit 3 is shown here, it may be provided separately. Further, the route presenting means 5 may present the optimum route to the occupant by voice.

FIG. 4 shows another example displayed on the route information presenting means 5. In this example, the vicinity of the intersection 33 in FIG. 2 is enlarged. In the enlarged map, the current position 34 and the optimal route 35 by the arrow
It is shown.

FIG. 5 is an explanatory diagram showing an example of the map information stored in the map information storage means 1. FIG. 5 (a)
It shows node data representing road junction information. The node data includes a node number for identifying a node (road junction), latitude and longitude indicating a coordinate position, a node name which is a node name, and names of facilities (gas stations, restaurants, etc.) near the node. , The number of connection links indicating the number of road segments connected to the node, the link number indicating each road segment to be connected, and the connection angle of each connected road segment to the node correspond to each node. Is set.

Although the node names and the facilities near the nodes are not necessary for calculating the optimum route, the route information providing means 5 uses the calculation result to assist the occupant in understanding the optimum route. Used as

FIG. 5B shows link data representing road segment information. The link data includes a link number for identifying a road segment (link), a start node number indicating a node connected to one of the links, an end node number connected to the other of the link, a road type indicating a road management classification, and a route. Number (National highway XX number, etc.), a common name of the road that indicates a generally used road, a link length that indicates the length of the link, a link traffic code that indicates whether or not one-way traffic is restricted and the direction, a total number of interpolation points, Latitude of each interpolation point
The longitude is set corresponding to each link.

Here, the method of selecting the start point and end point of the link is arbitrary. The link traffic code is set to be forward or reverse with respect to the direction of the link determined by the way of defining the start point and the end point. The interpolation point is for representing the shape of the link,
This is a point that is an end point of each minute straight line when the curve shape is approximated by a minute straight line group. The road alias and the interpolation point are not necessary for calculating the optimal route, but are used as auxiliary information when presenting the route information.

For example, map information corresponding to the map shown in FIG. 6 will be described. In FIG. 6, reference numerals 60 to 62 indicate nodes, and reference numerals 70 to 78 indicate links. In the node data representing the node 60, the number of connected links = 4, the link number of the connected link # 1 = 70, the link number of the connected link # 2 = 71, the link number of the connected link # 3 = 72, and the link of the connected link # 4. Number = 73. Taking the north direction as a reference of the connection angle, the connection angle of the connection link # 1 = 0 degrees, the connection angle of the connection link # 2 = 70 degrees, the connection angle of the connection link # 3 = 180 degrees, and the connection of the connection link # 4. Angle = 270
Degree.

FIG. 7 is an explanatory diagram showing an example of the area index information. The regional index information exists corresponding to all connection links of all nodes. And, in each region index information,
A degree of reachability indicating whether or not the connection link easily reaches each divided area when the route calculation target area is divided is set.

In the map shown in FIG. 6, the area divided by the dotted line is the divided area. For example, it is assumed that an optimal link from the node 61 to the divided area Ad is the link 74. It is assumed that the node 61 is the node (n) in FIG. Then, among the respective pieces of regional index information related to the node (n), the reachability “1” indicating that only the reachability of the divided area Ad of the regional index information corresponding to the link 74 is easy to reach is set. Links 75, 7
The reachability of each area index information corresponding to No. 6 with respect to the divided area Ad is set to “0”. FIG. 8 is an explanatory diagram showing how the reachability is set.
In the example shown in FIG. 6, the divided area is rectangular, but may be shaped according to natural topography such as rivers and mountains or administrative divisions.

Each area index information is created when the map information is created and is written in the map information storage means 1. For example, it is created as shown in the flowchart of FIG. That is, first, an arbitrary node in the route calculation target area is selected (step ST91). Then, the node is set as a departure place (step ST92).

Next, an arbitrary divided area within the route calculation target area is selected as a destination area (step ST93).
Then, an appropriate node in the destination area is set as a representative point (step ST94). The node serving as the representative point may be selected based on any criterion. However, if the node which is close to the center of gravity of the destination area graphic and which serves as a node of the main road is selected, the optimal route is selected. Gives good results when calculating

Next, an optimum route such as the shortest route between the departure place and the representative point is searched (step ST95). As a method used in searching for the optimum route, a mathematically established graph search algorithm such as the Dijkstra method or the potential method may be used.

A link flowing out of the departure point node is extracted from the obtained optimum route (step ST96). Then, step ST of the regional index information of the departure point node
Attention is paid to the regional index information of the link extracted at 96.
Of the reachability levels included in the area index information, the reachability level relating to the destination area is set to “1” (step ST9).
7). In addition, attention is paid to information other than the area index information of the link extracted in step ST96 among the area index information of each link connected to the departure point node. Then, for each of the regional index information, the reachability of the destination area among the reachability levels included in the regional index information is set to “0” (step ST98).

Next, step S is performed for all divided areas.
It is confirmed whether or not the processing from T94 to ST98 has been performed (step ST98). If there is an unprocessed divided area, one is selected from the unprocessed divided areas, and the processing of steps ST94 to ST98 is executed using the selected area as the destination area (step ST100).

When the above processing has been completed for all the divided areas for a certain node, it is confirmed whether or not the above processing has been performed for all the nodes (step ST).
101). If there is an unprocessed node, one is selected from the unprocessed nodes, and this is set as the departure point (step ST1).
02), the processes of steps ST94 to ST100 are executed. When the above processing is completed, the reachability to all the divided areas is obtained for all the connection links of all the nodes. The obtained respective degrees of reach are stored in the map information storage unit 1.
Is stored in

When the degree of reach is determined in this way, the degree of reach takes either "1" or "0", but the route obtained in step ST95 is not a single route but a representative point. If a plurality of routes are ranked according to the arrival cost, multi-level reachability can be set according to the arrival cost.

Although the case where the area index information corresponding to the node is created has been described here, the area index information corresponding to the link as shown in FIG. 10 may be created. Even when the area index information shown in FIG. 10 exists in the map information storage means 1, when the optimum route is actually obtained, the same result as when the area index information shown in FIG. can get.

Next, the operation of the navigation device shown in FIG. 1 for finding the optimum route will be described with reference to the flowchart of FIG. When an occupant inputs a departure place using the point input means 3, the optimal route calculation means 4
Enter the latitude and longitude of the point of departure from. When the current position of the moving object is set as the starting point, the current position information is input from the current position detecting means 2 and the current position is set as the starting point. Then, the node closest to the departure place is determined using the contents of the map information in the map information storage means 1, and is set as the departure place node (step ST111).

More specifically, the optimum route determination means 4 reads the map information shown in FIG. 5 from the map information storage means 1, and uses the latitude and longitude of each node and the latitude and longitude of the departure place to determine each node. The distance from the departure place is calculated, and the node closest to the departure place is set as the departure place node.

When the occupant inputs a destination using the point input means 3, the optimum route calculation means 4 inputs the latitude and longitude of the destination from the point input means 3. Then, the node closest to the destination is determined by using the contents of the map information in the map information storage means 1, and is set as the destination node (step ST112).

Next, a destination area including the destination is determined (step ST113). For example, when each divided area is defined by a rectangular area as shown in FIG. 6, mesh coordinates of the destination area are obtained by the following calculation. Longitudinal mesh coordinates of the destination area; MSx = INT (Px / Lx) (1) Longitudinal mesh coordinates of the destination area; MSy = INT (Py / Ly) (2) where Px; Longitude of the destination node [unit; second] Py; latitude of the destination node [unit; second] Lx; size of the destination area in the longitude direction [unit; second] Ly; size of the destination area in the latitude direction [unit; second] INT (); Integer part in ()

Next, the starting point node is set as a node to be inspected (inspection node) (step ST114). Then, the local index information of the inspection node is searched from the map information storage means 1 to determine a link (route link) which is a component of the optimal route, and the next node connected to the inspection node by the link is determined (step). ST115).

The processing of step ST115 is specifically executed as shown in the flowchart of FIG.
That is, first, among the connection links connected to the inspection node, the first link is set as the link to be inspected (inspection link) (step ST121). Then, area index information of the inspection link is obtained (step ST122), and the degree of ease of reaching the destination area is extracted (step ST122).
123).

If the reachability is "1", link information of the inspection link is extracted from the map information in the map information storage means 1 (steps ST124 and ST125). The start node and the end node are known from the link information. Since one of them is a check node, the other node different from the check node is set as the next node (step ST126).
The link to be inspected at this time is a route link.

If the reachability is not "1", it is confirmed whether or not the above processing has been performed for all the connected links, that is, whether or not the processing has been completed for that node (step ST127). If the processing is not completed, the next connection link is set as the inspection link (step ST128), and the processing of steps ST122 to ST124 is executed. When the processing is completed, it means that the route has reached a dead end before reaching the destination area.

As described above, the next node is determined. This next node is temporarily stored in the optimal route data as one of the nodes constituting the optimal route (step S
T116). Then, it is confirmed whether or not the determined next node is in the destination area (step ST117). If the route is within the destination area, it means that the route has arrived near the destination, and the process ends. If it is not within the destination area, the determined next node is set as the inspection node (step ST118), and the processing of steps ST115 to ST117 is executed.

As described above, each node on the optimal route from the departure point node to the destination area is set in the optimal route data. The optimum route calculation means 4 delivers the optimum route data to the route information presentation means 5. The route information presentation means 6
The map information is read out from the map information storage means 1 and the map is displayed on the display unit using the map information. Then, the optimum route determined by the optimum route data is displayed over the map. Alternatively, based on the relationship between the current position and the optimal route, the next intersection node that the moving body reaches is specified,
The map near the intersection is enlarged and displayed.

In this embodiment, a case has been described in which the optimum route is displayed after all nodes on the optimum route to the destination area are obtained. However, the optimum route calculation means 4 obtains the nodes on the optimum route. Each time, the information on the node may be passed to the route information presenting means 5. In that case, each part constituting the optimum route is sequentially displayed on the display unit.

Embodiment 2 FIG. The route obtained as the optimal route in the above embodiment is a route from the departure node to the representative point node near the destination node, but may not be optimal as a route to the destination node.

For example, consider the case of the route shown in FIG. In FIG. 13, 131 is a departure node and 132 is a destination node. 141 and 142 are divided areas set in advance. 133 is divided area 1
Reference numeral 41 denotes a representative point node, and reference numeral 134 denotes a representative point node in the divided area 142. 135 is a node in the divided area 141, and 136 is a node in the divided area 142. In this case, the destination area is the divided area 141 including the destination node 132.

According to the first embodiment, the route determined as the optimum route is from the departure point node 131 to the node 134.
Is a path a that reaches the node 135 via. When the occupant follows the presented optimal route, to reach the destination node 132, after arriving at the node 133, the user once goes to the node 133 and then travels along the route b toward the node 132. However, the truly optimal path is obviously path c, which passes through node 136 to destination node 132.

The route a is on the route to the representative point calculated when the area index information is created. Therefore, even if the optimum route calculation is performed up to the representative point node in the destination area, the obtained optimum route is the route to the representative point node 133. Has the same effect as if

In this case, it is better to calculate the optimum route for the divided area 142 before the destination area 141 and leave the selection of the route from the divided area 142 to the destination node 132 to the occupant. This becomes particularly important when the final route to the destination node is determined by a point-to-point route search.

Therefore, a second embodiment in which each divided area is configured so that a part of the divided area is included in another divided area as shown in FIG. In this case, as shown in FIG. 14, each divided area is defined as one in which the divided area in the first embodiment is spread in all directions by a distance d while keeping its center of gravity. The configuration of the navigation device according to the second embodiment may be the configuration shown in FIG. 1, although the operation of the optimum route calculation means 4 is different, and the area index information stored in the map information storage means 1 is This is the same as in the first embodiment.

The following method is also available as a method of forming a divided area. The first divided area group is based on each rectangular divided area like the divided area group in the first embodiment. The second divided area group is constituted by rectangles having the same shape such that the vertices of the rectangles forming the first destination area group have diagonal intersections. Then, the first divided area group and the second divided area group cover the route calculation target range. In addition, the first divided area group is based on the administrative division area, and the second divided status area group is based on each divided area having a central area near the line of the administrative division.

The case where the division shown in FIG. 14 is made will be described below. When the departure place and the destination are input, also in this case, the same processing as the processing in the first embodiment shown in FIG. 11 is executed to determine the optimum route. However,
In this case, unlike the case of the first embodiment, the method of determining the destination area is executed as shown in the flowcharts of FIGS.

First, when the destination node (Px, Py) is given, as shown in the flowchart of FIG.
Find the mesh coordinates of the area that can be the destination area. First, the optimum route calculation means 4 calculates (Px / Lx) and (Py / Ly) by using the equations (1) and (2) (step ST151), and obtains MSx and MSy. These are set as destination area mesh coordinate candidates (step ST1).
52).

Then, it is confirmed whether or not the equation (3) is satisfied (step ST153). FRAC (Px / Lx) ≦ (d / Lx) (3) If the expression (3) holds, the destination area on the left side of the division area corresponding to the mesh coordinates obtained in step ST152 is also the destination node. MSx-1
Is added to the candidate for the destination area mesh coordinates in the longitude direction (step ST154). Note that FRAC () indicates a decimal part in ().

Further, it is confirmed whether or not the equation (4) is satisfied (step ST155). 1-FRAC (Px / Lx) ≦ (d / Lx) (4) If the expression (4) holds, the division area on the right side of the division area corresponding to the mesh coordinates obtained in step ST152 is also used. MSx + 1
Is added to the target area mesh coordinate candidates in the longitude direction (step ST156).

Further, it is confirmed whether or not the equation (5) is satisfied (step ST157). FRAC (Py / Ly) ≦ (d / Ly) (5) When the expression (5) is satisfied, the divided area on the lower side of the divided area corresponding to the mesh coordinates obtained in step ST152 is also a destination node. MSy-1
Is added to the target area mesh coordinate candidates in the latitude direction (step ST158).

Further, it is confirmed whether or not the expression (6) is satisfied (step ST159). 1-FRAC (Py / Ly) ≦ (d / Ly) (6) If the expression (6) holds, the upper divided area corresponding to the mesh coordinates obtained in step ST152 is also used. MSy + 1
Is added to the target area mesh coordinate candidates in the latitude direction (step ST160).

Finally, steps ST152 to ST160
From the combinations of all the destination area mesh coordinate candidates obtained in the above, the optimum route calculation means 4 determines the destination area candidates. For example, the destination area mesh coordinate candidates are MSx-1,
If it is MSx, MSy, the destination area candidate is (MSx
-1, MSy) and (MSx, MSy). The destination area mesh coordinate candidates are MSx-1, MSx, MSy,
If MSy + 1, the destination candidate is (MSx−
1, MSy), (MSx, MSy), (MSx-1, M
Sy + 1) and (MSx, MSy + 1).

Then, the optimum route calculation means 4 selects one destination area from the determined destination area candidates by the processing shown in the flowchart of FIG. That is, first, a representative point of each destination area candidate is determined (step ST162). For example, the center of gravity of the figure of the destination area candidate is obtained, and this is set as the representative point. Alternatively, the representative point used at the time of creating the regional index information may be stored and used.

Next, for each representative point, the angle between the direction in which the departure point node is viewed from the representative point and the direction in which the destination node is viewed from the representative point is calculated (step ST16).
3). Then, the destination area candidate including the representative point having the maximum angle is set as the destination area (step ST164). FIG.
In the case of the map shown in FIG. 4, the destination area candidates including the destination node 132 are two divided areas 143 and 144.
The representative points are nodes 133 and 134, respectively. The angle at which the departure point node 131 and the destination node 132 are viewed from the representative point node 133 is acute, and the angle at which the departure point node 131 and the destination node 132 are viewed from the representative point node 134 is obtuse. Therefore, node 1
The divided area 144 including the area 34 is set as the destination area.

The method of selecting a destination area is not limited to the processing shown in the flowchart of FIG. For example, the selection may be made based on toll road priority conditioning or toll road avoidance conditioning.

Hereinafter, the optimum route is obtained by the same processing as the processing in the first embodiment, and the route is presented to the occupant. If you have the map shown in FIG.
According to the first embodiment, a point that is farther from the destination than the destination is presented as the optimal route. On the other hand, according to this embodiment, a point that is closer to the point of departure than the point of destination is presented as the optimal route.

Embodiment 3 FIG. In the first embodiment, as the degree of division is increased and the size of the divided area is reduced, the end point of the optimal route can be closer to various destinations. On the other hand, when the size of the divided area is reduced, there is a disadvantage that the amount of the area index information increases and the required memory capacity increases.

The navigation apparatus according to the third embodiment can solve such a drawback. As the area index information, a wide area corresponding to a wide area divided area covering a wide area by coarse division. It has index information and narrow area index information corresponding to a narrow area divided area that covers a narrow area by dense division. The regional index information of each connection link of each node includes the ease of reaching a wide area divided area not including the node and the ease of reaching each narrow area divided including the wide area divided area including the node. are doing. The configuration of the navigation device according to the third embodiment may be the configuration shown in FIG. 1, although the contents of the map information storage means 1 and the operation of the optimum route calculation means 4 are different.

FIG. 17 is an explanatory diagram showing wide area division and narrow area division. In the figure, a and b are symbols indicating a wide area index of a wide divided area obtained by roughly dividing the route calculation target area in the longitude direction, and A and B are roughly dividing the route calculation target area in the latitude direction. This is a symbol indicating the wide area index of the obtained wide area division area. Reference numerals 1 and 2 in FIG. 17 indicate a narrow area index. The road network is the same as that shown in FIG.

FIG. 18 shows area index information corresponding to wide area division and narrow area division. In the figure, the configuration of the left column and the center column is the same as that shown in FIG. The configuration in the right column corresponds to a multi-stage area division as shown in FIG. FIG. 18 shows a case where the node (n) is located in the wide area divided area Ba. Therefore, the reachability of the wide divided area Ba to the narrow divided area constituting the area is indicated. In FIG. 18, 18
Numeral 1 indicates the degree of ease of reaching the wide area division area, and 182 indicates the degree of ease of reaching the narrow area division area. In order to create such area index information, the method used in the first embodiment may be applied to each of the wide area division area and the narrow area division area.

When such area index information is set in the map information storage means 1, the optimum route calculation means 4 executes a process as shown in the flowchart of FIG. However, the process of determining the next node in step ST115 is not executed as shown in the flowchart of FIG. 12, but is executed as shown in the flowchart of FIG. Also,
In this case, in step ST113 of FIG.
The wide area division area including the destination node is set as the destination area.

That is, first, the first connection link connected to the check node is set as the check link (step ST19).
1). Next, it is confirmed whether or not the inspection node belongs to the wide area division area that is the destination area (step ST192). If it belongs, there is narrow area search information, so narrow area index information of the inspection link is obtained (step ST19).
3) Then, the degree of ease of reaching the destination area is extracted (step ST195). The destination area here is a narrow divided area.

If the test node does not belong to the wide area divided area which is the destination area, wide area index information of the test link is obtained (step ST194), and the degree of ease of reaching the destination area is extracted (step ST195). . The destination area here is a wide area division area.

If the reachability is "1", the link information of the inspection link is extracted from the map information in the map information storage means 1 (step ST197). The start node and the end node are known from the link information. The node different from the check node is set as the next node (step ST1).
98).

If the reachability is not “1”, it is checked whether the above processing has been performed for all the connected links, that is, whether the processing has been completed for the node (step ST199). If the processing is not completed, the next connection link is set as the inspection link (step ST200), and the processing of steps ST192 to ST1196 is executed. When the processing is completed, it means that the route has reached a dead end before reaching the destination area.

As described above, the next node is determined. Subsequent processing is the same as the processing in the first embodiment. As described above, the route is calculated using the wide area index information up to the vicinity of the destination area, and once the vehicle enters the wide area divided area which is the destination area, the route is calculated using the narrow area index information. Become. When the calculation of the route is completed, the optimum route data is delivered to the route information presenting means 5 as in the case of the first embodiment. The route information presenting means 5 presents route information to the occupant using the optimal route data.

As can be seen by comparing FIG. 6 with FIG. 17, the minimum unit of the divided area is the same as in the first embodiment. However, the number of reachability per node / link has decreased from 16 (see FIG. 7) to 8 (see FIG. 18).

Embodiment 4 FIG. In the first embodiment, the shape of the divided area is a rectangular shape. The rectangular shape has the advantage that the area index information can be easily created and the destination area to which the destination node belongs can be easily determined, but has the following disadvantages.

Consider a case where an optimal route to a destination and an optimal route to another destination near the destination and belonging to an adjacent divided area are determined. The two optimal routes should be almost identical, but according to the first embodiment, at the end of the route, they will be separated toward the representative point of each destination area. In such a case, in order to bring the final part of the route closer, the boundary between the divided areas should be set as sparsely as possible on the road. However, such settings cannot be made using each of the predefined divided areas. The problem is even greater when the divided area is rectangular.

That is, the actual road network is not uniformly distributed, and dense areas such as urban areas and sparse areas such as suburbs and mountain areas are mixed. If rectangular area division is uniformly applied to such a road network, it is inevitable that a division boundary line is set in a dense area of roads.

The navigation apparatus according to the fourth embodiment reduces such a problem, and uses a divided area set according to the administrative division.
The administrative divisions are often set in relation to natural terrain such as mountains and rivers, or are set so as to include urban areas based on the history of urban development. Therefore, if the divided area is set according to the administrative division, as shown in FIG. 20, as a result, a boundary is set in a sparse place of the road network. In FIG. 20, the dashed line indicates the boundary of the administrative division, that is, the boundary of the divided area in this embodiment.
The configuration of the navigation device according to the fourth embodiment may be the configuration shown in FIG. 1, although the contents of the map information storage means 1 and the operation of the optimum route calculation means 4 are different.

FIG. 21 is an explanatory diagram showing the area index information in this embodiment. In the figure, the configuration of the left column and the center column is shown in FIG.
Is the same as that shown in FIG. The configuration in the right column is a collection of the ease of reaching each administrative division area (administrative boundary).
To create such area index information, the method used in the first embodiment may be used. The representative point required at that time may be near the center of gravity of a closed curved surface formed by the administrative division, or may be near an administrative agency or a main station considered to be in a densely populated road area.

When such area index information is set in the map information storage means 1, the optimum route calculation means 4 executes a process as shown in the flowchart of FIG. However, in this case, steps ST113 and ST117
When determining the area to which the node belongs, the administrative boundary data shown in FIG. 22 is required. The administrative boundary data is set in the map information storage unit 1. In the administrative boundary data, the circumscribed rectangle is a rectangle including a closed curved surface formed by the administrative division. The interpolation point is a vertex when a closed curved surface formed by the administrative division is approximated by a polygon.

When determining the area to which a node belongs, the optimum route calculation means 4 compares the coordinates of the node with the coordinates of a circumscribed rectangle in each administrative boundary data to determine the administrative boundary to which the node belongs. A point that is not included in the circumscribed rectangle cannot be included in the administrative boundary included in the rectangle. Therefore, by referring to the coordinates of the circumscribed rectangle, the administrative boundary to which the node may belong can be quickly extracted.

Then, for the extracted administrative boundary, the destination area to which the node belongs is determined according to the algorithm for including points in a polygon. There are several well-known algorithms for this, for example, the following.

In FIG. 23, 231 is a polygon corresponding to the administrative boundary. A line segment is drawn from any point toward one vertex of the polygon 231. In addition, a line segment is drawn from the arbitrary point to a vertex adjacent to the vertex. And 2
Find the angle between two line segments. When angle calculation processing is performed for all vertices and the calculated angles are added, if an arbitrary point is inside the polygon 231 as shown by P1 in FIG. 23, the added value of the angles a1, a2,. Becomes 360 degrees. On the other hand, if it is outside the polygon 231 as in P2, the added value of the angles b1, b2,. Therefore, by evaluating the angle addition value, it is possible to determine whether the node is inside or outside the polygon 231.

The other processing is the same as the processing in the first embodiment. Therefore, the optimum route is calculated as in the case of the first embodiment. The optimum route calculating means 4 transfers the optimum route data to the route information presenting means 5 as in the case of the first embodiment. The route information presenting means 5 presents route information to the occupant using the optimal route data.

Embodiment 5 FIG. The navigation device according to the first embodiment has a configuration for solving the conventional problem that the route calculation time increases exponentially as the search distance increases. However, the memory capacity is increasing because of having the regional index information which is not available in the conventional device.

The navigation device according to the fifth embodiment can reduce the calculation time while suppressing an increase in the memory capacity. In general, arterial roads such as national roads and major land reports occupy the majority of long-distance routes.
Therefore, in this case, regional index information is set only for nodes on the main road. The configuration of the navigation device according to the fifth embodiment may be the configuration shown in FIG. 1, although the contents of the map information storage means 1 and the operation of the optimum route calculation means 4 are different.

The area index information created in advance is created as shown in the flowchart of FIG. 9, as in the case of the first embodiment. However, when nodes are determined in steps ST91 and ST102, only nodes on the main road are targeted. That is, step ST91
In step ST102, when the link data for connecting to the node is obtained according to the map information shown in FIG. 5, the road type in the link data is determined. A node to which a link whose road type is, for example, a national road or a main local road is connected is set as a regional index information creation target node.

The area index information created in this manner is set in the map information storage means 1. The optimum route calculation means 4 calculates the optimum route by a process as shown in the flowchart of FIG.

When the departure place is input, the node closest to the departure place is set as the departure place node (step ST24).
1). Then, the node on the main road closest to the departure point node is determined by referring to the map information in the map information storage means 1 (step ST242). This is defined as a main line departure point node. When the destination is input, the node closest to the destination is set as the destination node (step ST24).
3) The divided area including the destination node is set as the destination area (step ST244). Step ST241, ST
The processing of steps 242 and ST244 is the same as the processing of steps ST111, ST112 and ST113 in FIG.

Next, a graph search is performed between the departure point node and the main line departure point node. The resulting link on the optimal road between the departure point node and the main departure point node is stored in the optimal path data (step ST245).

As the graph search method, the Dijkstra method, the A ^* method, and the like described above can be used. For example, a graph search method is applied using the link length in the map information shown in FIG. 5 as a basic parameter of the evaluation, and taking into account the link traffic code, the adjustment of the deemed link length due to the difference of the road type, and the adjustment of the number of right and left turns A route with the lowest arrival cost from the departure point node to the main line departure point node is obtained by adding a small amount of evaluation.

The optimum route from the main node to the destination is determined by steps ST114 to ST11 in FIG.
It is obtained by the same processing as the processing up to 8. That is, the main departure point node is set as the inspection node (step S
T246). Then, the area index information of the inspection node is searched from the map information storage means 1, a route link which is a component of the optimal route is determined, and the next node connected to the inspection node by the link is determined (step ST247).

Next, the determined next node is temporarily stored in the optimum route data as one of the nodes constituting the optimum route (step ST248). Then, it is confirmed whether or not the determined next node is in the destination area (step ST249). If the route is within the destination area, it means that the route has arrived near the destination, and the process ends.
If it is not within the destination area, the determined next node is set as the inspection node (step ST250), and the
247 to ST249 are executed.

As described above, each node on the optimal route from the departure point node to the destination area via the trunk departure point is set in the optimal route data. Here, the route from the departure point node to the main line departure point node is obtained by using a graph search technique. Although the calculation time increases exponentially by using this method, the calculation load does not increase so much because the calculation time is exponentially applied to some of the routes until reaching the main road.

The optimum route calculating means 4 delivers the optimum route data to the route information presenting means 5. Route information presentation means 6
Reads map information from the map information storage means 1 and displays a map on the display unit using the read map information. Then, the optimum route is displayed thereon.

Embodiment 6 FIG. If the vehicle can reach a highway or an arterial road when traveling, in general, the route can be determined from the knowledge of the occupants themselves or information from road signs. Therefore, there is a demand that at least the route to the main road be presented from the navigation device.

The navigation device according to the sixth embodiment is for responding to such a request, and is for quickly obtaining a route to a main road. That is,
Provide arterial road index information that describes the ease of reaching from a node on a non-arterial road to a nearby arterial road,
The route link to the main road is determined by evaluating this information. The configuration of the navigation apparatus according to the sixth embodiment may be the configuration shown in FIG. 1, although the contents of the map information storage means 1 and the operation of the optimum route calculation means 4 are different.

The road network shown in FIG. 25 is taken as an example. In the figure, the road to which "10" is added is expressway No. 10. The road with “1” is National Highway 1, and the road with “2” is National Highway 2.

FIG. 26 is an explanatory diagram showing an example of main road index information. In the figure, the left column and the center column are the same as those shown in FIG. In the right column, the number of main road index information that can be searched for at the node, the road type of each main road, the line number of each main road, and the ease of reaching each main road are described.

The main road index information is created as shown in the flowchart of FIG. First, an appropriate node is selected (step ST271), and that node is set as a departure node (step ST272). Next, nodes within a predetermined range from the departure point node and located on the main road are extracted (step ST273). The extracted nodes are grouped for each main road (step ST274). Here, it is assumed that the node at the intersection of the main roads belongs to both the main roads.

The node closest to the departure point node among the nodes grouped for the same road is set as a representative node of the main road (step ST275). The above processing will be described for the road network shown in FIG. Here, the description will focus on the node 251. The representative node of each highway is node 252,
Node 253 for National Highway 1 and Node 254 for National Highway 2.

Next, one of the representative nodes is set as a destination node (step ST276). The road type and the line number of the road to which the destination node belongs are set in the main road index information (step ST277). For example, node 252
Is the destination node, the road type of the first main road is “Expressway” and the route number is “10”.

Next, an optimal route search is performed from the departure point node to the destination node (step ST278), and a link connected to the departure point node is obtained from the obtained routes (step ST279). For example, when the node 252 is set as the destination node, the link 257 is obtained.

In the acquired arterial road index information of the link, the degree of ease of reaching the arterial road in question is “1”.
And, among the main road index information in the other connecting link directions, the degree of ease of reaching the current main road is “0”.
(Step ST280). For example, node 251
In the main road index information, the ease of reaching the first main road (in this example, expressway No. 10) among the road index information in the link 257 direction is “1”, and the road index information in the other link directions is “1”. Among them, the degree of ease of reaching the first main road is “0”.

Then, steps ST277 to ST280 are performed.
Is performed on all representative nodes (steps ST281 and ST282). As a result of the above processing, the node 251 has the link 256
The degree of ease of reaching the second arterial road in the arterial road index information in the direction is “1”, and the link 25 is linked to National Highway 2
The degree of ease of reaching the third main road among the five directions of main road index information is “1”.

When all the highway index information is determined for one node, the number of highway index information is set.
Then, the departure point node is changed (step ST28).
4), the processing of steps ST272 to ST282 is executed. When the above process has been performed for all nodes, the process ends (step ST283).

As described above, the main road index information is created. Then, the main road index information is stored in the map information storage means 1. The optimum route calculating means 4 calculates the optimum route by using the main road index information preset in the map information storage means 1 by the processing shown in the flowchart of FIG. Hereinafter, the operation of the optimum route calculation will be described.

First, the node closest to the departure point set by the point input means 3 is determined by using the latitude and longitude of each node in the map information in the map information storage means 1,
The node is set as the departure point node (step ST28)
5). Next, a destination road serving as a destination is determined (step ST286). The determination of the destination road is executed, for example, as shown in the flowchart of FIG.

That is, the optimum route calculation means 4 first
The main road index information of the departure point node is obtained from the main road index information in the map information storage means 1 (step ST29).
2). Each type of main road and each line number described in the main road index information are delivered to the point input means 3. The point input means 3 displays them as a list of main road names (step ST293). When the occupant selects one trunk road name from the displayed trunk road name list (step ST294), the point input means 3 displays the road type and the line number of the selected trunk road and the destination road. To the optimal route calculation means 4.

The destination road is determined as described above.
Then, the optimal route calculation means 4 sets the departure point node as the inspection node (step ST287), and searches the main road index information of the inspection node to determine the next node forming the optimal route (step ST288). The determination of the next node is executed, for example, in the same manner as the processing shown in the flowchart of FIG.

That is, first, among the connection links connected to the check node, the first link is set as the check link. Then, the main road index information of the inspection link is acquired, and the ease of reaching the destination road is extracted. If the reachability is “1”, the link information of the inspection link is extracted from the map information in the map information storage unit 1. The start node and the end node are known from the link information. The node that is different from the check node is the next node

When the next node is obtained, the optimum route calculation means 4 temporarily stores it in the optimum route data (step ST289), and then determines whether the obtained next node is a node on the destination road (step ST289). ST290). If it is not a node on the destination road, the obtained next node is set as an inspection node (step ST291), and the processes of steps ST288 to ST290 are executed until the destination road is reached. To determine whether the next node is on the destination road, link data of all links connected to the next node is acquired from the map information, and the road type and route number are included in the link data as those of the destination road. What is necessary is just to determine whether there is a match.

When the route search reaches the destination road, the optimum route calculation means 4 delivers the optimum route data to the route information presenting means 5. The route information presentation means 6 reads the map information from the map information storage means 1 and displays the map on the display unit using the read map information. Further, the optimum route is displayed thereon.

Embodiment 7 FIG. The navigation apparatus according to the first to fifth embodiments calculates the optimum route toward the destination area including the destination node while referring to the area index information. According to these navigation devices, the time required for route calculation is shorter than that of the conventional navigation device. However, there are the following disadvantages.

That is, when creating the regional index information, a certain representative point is set in the destination area, and a graph search is performed toward the representative point. Therefore, when the destination node is far from the representative point of the destination area, as the route calculated by the route calculation using the regional index information approaches the destination, the route deviates from the true optimal route. There is. Such a problem can be solved by reducing the size of the divided area, but in such a case, the data amount of the area index information increases. Therefore, there is a limit to reducing the size of the divided area. Note that the navigation device according to the second embodiment also prevents the deviation between the end point of the optimum route and the destination, but the calculated end point of the optimum route remains in the destination area.

The navigation device according to the seventh embodiment further effectively prevents the deviation between the end point of the optimum route and the destination. The configuration of this navigation device may be the same as the configuration shown in FIG. 1, but in this case, the optimal route calculating means 4 calculates the distance between the tip of the optimal route determined using the regional index information and the destination. Is smaller than a certain value, the use of the regional index information is stopped and the point-to-point route search is executed.

The operation will be described below with reference to the flowchart in FIG. In the map information storage means 1,
The same regional index information as in the first embodiment is set. When the departure value and the destination value are set, the optimum route calculation means 4 determines the node closest to the departure point from the latitude and longitude of each node in the map information, and sets the determined node as the departure point node ( Step ST301). By the same processing, the node closest to the destination is set as the destination node (step ST302), and the destination area to which the destination node belongs is determined (step ST303).

Next, the departure point node is set as a check node (step ST304). And the map information storage means 1
, The area index information of the inspection node is searched, the route link is determined, and the next node connected to the inspection node by the link is determined (step ST305).

The determined next node is temporarily stored in the optimum route data as one of the nodes constituting the optimum route (step ST306). The above processing is the same as the processing in steps ST111 to ST116 shown in FIG.

Next, the determined latitude / longitude of the next node is obtained from the map information, and a straight-line distance to the destination node is calculated from them and the latitude / longitude of the destination node. It is compared with the threshold distance (step ST307). If the straight line distance is larger than the threshold distance, the determined next node is set as a check node (step ST310), and steps ST305 to S305 are set.
The processing of T307 is executed. The threshold distance is set larger than the diagonal distance of the divided area. Therefore, when the process proceeds from step ST307 to ST308, the determined next node is outside the destination area.

If it is determined in step ST307 that the next node is within the threshold distance, the route search using the regional index information is stopped, and a graph search between two points is performed from the next node toward the target value node. (Step ST30
8). As a graph search method, Dijkstra method or A ^*
Method can be used. These methods are applied to a road network defined by node data and link data in map information, and a search for an optimum route is performed by evaluating appropriate parameters such as a path length.

When the optimal route from the next node to the target value is obtained by the graph search, it is temporarily stored in the optimal route data (step ST309). Then, the route calculation ends. The optimum route calculation means 4 delivers the optimum route data to the route information presentation means 5. The route information presentation means 6
The map information is read out from the map information storage means 1 and the map is displayed on the display unit using the map information. Further, the optimum route is displayed thereon.

Although the time required for the graph search exponentially increases as the path length increases, in this embodiment, the graph search is executed for a short distance of the final path, so that the total time for the optimal path calculation is significantly increased. The optimum route to the target value can be obtained in a state where the process is not performed.

Embodiment 8 FIG. The navigation device according to each of the above embodiments, when a destination area or a destination road is set,
The optimal route was obtained using fixed index information. However, recently, a system for measuring a traffic congestion state of a road and the like and transmitting the measurement result as wireless real-time traffic information to a mobile object is being developed. Therefore, it is required to present an optimal route according to the traffic congestion using real-time traffic information. On the other hand, it is meaningless to use real-time traffic information for long-distance route search. This is because the situation often changes when arriving at the point even if the information on the distant point at that time is used. Therefore, route search using real-time information should be limited to a range that is not so wide from the current position where real-time traffic information is effective empirically.

FIG. 31 is a block diagram showing a configuration of a navigation device according to the eighth embodiment of the present invention based on such a concept. This navigation device includes traffic information receiving means 6 for receiving real-time traffic information in addition to the components of the navigation device according to each of the above embodiments.
It has. The traffic information is transmitted via channels such as wide area broadcast communication multiplexed with broadcast waves and intermittent narrow zone communication such as a beacon.

Further, the optimum route calculation means 4 sets the traffic information application area within a predetermined range from the current position of the moving object,
Perform a route search taking into account traffic information. That is, the route determined using the index information is set as a temporary route, and a search start point and a search end point are set on the temporary route included in the traffic information application area. Then, ease of passage considering traffic conditions is added to links in the traffic information application area, and a two-point route search is performed from the search start point to the search end point. further,
The section from the search start point of the temporary route to the search end point is
Replace with the result of the point-to-point search. In the map information storage means 1, map information shown in FIG. 5 and area index information shown in FIG. 7 are set.

FIG. 32 is an explanatory diagram showing an example of the format of the traffic information data to be transmitted. In the traffic information data, the congestion status measured by the road supplementary facilities is described as the congestion degree for each link. For example, the congestion degree “0”
Indicates that the vehicle is flowing smoothly on the link, and that the average moving speed of the vehicle decreases and the traffic is congested as the number of the degree of congestion increases. It is assumed that each link in the traffic information data is associated with a link in the map information stored in the map information storage unit 1.

Further, the traffic information data may include, in addition to the degree of congestion, information related to the head of a congestion position and the length of congestion from there, and information on temporary traffic regulation due to accidents or construction. These factors may be included in the evaluation index described below.

Next, the process of calculating the optimum route will be described with reference to the flowchart of FIG. When the departure value and the destination value are set, the optimum route calculation means 4 sets the node closest to the departure point to the departure point node, sets the node closest to the destination to the destination node, and determines the destination area to which the destination node belongs. It is determined (step ST331). Here, the node 341 in FIG.
It is assumed that 2 is a destination node and the divided area Ad is a destination area. In the figure, 340 is a symbol indicating the current position.

Next, the departure point node is set as a check node (step ST332). And the map information storage means 1
To determine the route link by searching for the area index information of the inspection node from, and determine the next node connected to the inspection node by the link (step ST333).

The determined next node is temporarily stored in the optimum route data as one of the nodes constituting the optimum route (step ST334). The above processing is the same as the processing in steps ST111 to ST116 shown in FIG.

Next, it is determined, using the latitude and longitude in the map information, whether or not the inspection node is within a predetermined range from the current position of the moving object detected by the current position detection means 2 for the first time (step ST335). . If entered for the first time, the check node is temporarily stored as a search start node (step ST336). If the next node is within a predetermined range, it is determined whether or not the next node has come out (step ST337).
If it has come out, the check node is temporarily stored as a search end node (step ST338). The predetermined range is
This is a range included in the traffic information application area set in advance.

Further, it is determined whether or not the next node has entered the destination area (step ST339). If not, the next node is set as a check node (step ST34).
0), the processes of steps ST333 to ST339 are executed. Through the above processing, the optimum route using the regional index information, the search start node and the search end node are determined. In FIG. 34, it is assumed that p → q → r is the calculated optimal route. Further, assuming that the position indicated by the symbol 340 is the current position and the traffic information applicable range is within a circle having a radius L centered on the current position, the node 343 becomes the search start node, and the node 344 becomes the search end node.

Next, the optimum route calculation means 4 performs a graph search in consideration of traffic information between the search start node and the search end node (step ST341). This graph search is executed, for example, as shown in the flowchart of FIG.

That is, the optimum route calculation means 4 acquires map information from the map information storage means 1 (step ST3).
51). Further, the traffic information data shown in FIG. 32 is obtained via the traffic information receiving means 6 (step ST352).
Next, an assumed distance according to the traffic information is added to the link length in the map information (step ST353). For example, the congestion degree of the link in the traffic information data is inspected, and the link length to which the congestion degree is not transmitted and the link whose congestion degree is “0” are set to 0 as the assumed distance increment due to the congestion and the link length is directly applied I do. For a link having a degree of congestion other than “0”, a link length is multiplied by a coefficient that increases the deemed distance as the degree of congestion increases.

Then, a graph search is performed between the search start node and the search end node using the link length as an evaluation parameter by the Dijkstra method, the A ^* method, or the like for the road network in consideration of the assumed distance (step ST354). . When the result of the graph search is obtained, the result is temporarily stored, and the graph search ends (step ST355).

When the graph search is completed, the route between the search start node and the search end node among the optimal routes obtained using the regional search information is replaced with the stored graph search result (step ST342). .

For example, in FIG. 34, it is assumed that there is congestion on the link 345. Then, since the assumed distance of the link is large, the optimal route between the search start node and the search end node is changed to s. Therefore, the optimal route from the departure point node to the destination node is changed from p → s → r.

The optimal route calculating means 4 delivers the optimal route data to which the traffic information is added to the route information presenting means 5.
The route information presentation means 5 reads the map information from the map information storage means 1 and displays a map on the display unit using the read map information.
The route based on the optimal route data is displayed. As described above, the optimum route considering real-time traffic information can be presented to the occupant without increasing the calculation time for long-distance route search.

Although the departure point and the current position are described as different points for generalization of the description, the current position may be set as the departure point. In that case, an optimal route including the current position is obtained.

Also, here, a case has been described in which real-time information is applied to the navigation device according to the first embodiment. However, real-time information is applied to the navigation device according to the sixth embodiment, including the navigation device according to the sixth embodiment. You can also. Since the operation in those cases is similar to the above operation, detailed description of the operation is omitted.

Embodiment 9 FIG. In the first embodiment, since the shape of the divided area is a rectangle, the destination to which the destination node belongs is easily determined by the equations (1) and (2). It was also easy to determine whether the node at the tip of the route reached the destination area during route calculation. However, in the navigation device according to the first embodiment, the end point of the obtained optimal route may be far from the destination. Therefore, a measure that does not make the divided area rectangular was effective. For example, in the fourth embodiment, the divided areas are determined according to the administrative boundaries.

The determination as to whether or not the node at the leading end of the route has reached the destination area needs to be executed each time one node constituting the optimum route is determined. Therefore, it is desirable that the determination be made as simple as possible in order to reduce the calculation time. When the divided area is adjusted to the administrative boundary as in the fourth embodiment, it is necessary to perform a large number of angle calculations to confirm the inclusion relation of polygons at the time of the determination, and an increase in calculation time can be avoided. Absent.

The navigation device according to the ninth embodiment does not increase the time required to determine the inclusion of the destination area even if the divided area is not rectangular.
The configuration of the navigation device is similar to the configuration shown in FIG. 1 except that information for easily identifying the destination area to which the node belongs is added to the map information storage means 1 and the operation of the optimum route calculation means 4 is different. It is.

FIG. 36 is an explanatory diagram showing an example of map information set in the map information storage means 1 in the navigation device according to this embodiment. FIG. 36A shows node data. In the node data, a divided area code to which the node belongs follows the node number. The method of assigning the divided regions is based on a system that can uniquely specify each divided region. For example, if the divided area is a rectangle, an area mesh code can be considered. Further, if it is in line with the administrative boundaries, an administrative code assigned to each administrative boundary can be considered. Other parts of node data and FIG.
The content of the link data shown in (b) is the same as that shown in FIG.

The area index information set in the map information storage means 1 is the same as that shown in FIG. Therefore, the first
It is created in the same manner as in the embodiment. The node number of the representative point node of the divided area selected at the time of creating the area index information may be used as the divided area code to which the node belongs.

Next, the operation will be described. The navigation apparatus according to this embodiment uses the divided area code to which the node belongs, but calculates the optimum route by the same processing as the processing shown in FIG. That is, when the departure value and the destination value are set, the optimum route calculation means 4 determines a node closest to the departure place, and sets the determined node as a departure place node. The node closest to the destination is set as the destination node, and the destination area to which the destination node belongs is determined. When determining the destination area, the node data of the destination node is acquired from the map information storage means 1, and the divided area code to which the node belongs in the node data is referred to. With the code, the destination area can be immediately determined.

Next, the starting point node is set as a check node.
The route index is determined by retrieving the area index information of the inspection node from the map information storage means 1, and the next node connected to the inspection node by the link is determined. The determined next node is temporarily stored in the optimum route data as one of the nodes constituting the optimum route.

Then, it is determined whether the next node is a node in the destination area. If the node is not within the destination area, the above processing is executed until the destination area is reached, using the obtained next node as a check node. Whether or not the next node is within the destination area can be immediately determined by the divided area code to which the node belongs in the node data.

When the calculation of the optimum route is completed, the optimum route calculating means 4 sends the optimum route data to the route information presenting means 5.
Hand over to The route information presentation means 6 reads the map information from the map information storage means 1 and displays the map on the display unit using the read map information. The route based on the optimal route data is displayed.

Embodiment 10 FIG. In each of the above embodiments, a clear point is set as the destination. However, considering the actual situation of use of the navigation device, "XX prefecture XX city"
If the general area can be designated as the destination as in the above, it may be enough for the crew. In such a situation, if the occupant sets a clear point as the destination, the occupant is forced to perform operations such as designation of enlargement of the display map and scrolling, which makes the navigation device inconvenient.

The navigation device according to this embodiment is
The destination can be set without the occupant setting a clear point, and the optimum route to the destination is presented. That is, it is possible to directly set the divided area described in the area index information in the first embodiment or the main road described in the main road index information in the sixth embodiment as the destination. The configuration of the navigation apparatus according to the present embodiment may be the same as the configuration shown in FIG. 1, although the information set in the map information storage means 1 is different and the operation of the point input means 3 is different.

FIG. 37 is an explanatory diagram showing an example of area name information set in the map information storage means 1. A region name and a region code are set in the region name information. The area name is a place name representing the area, and the area code is a code specifying the divided area described in the area index information. The area name information is arranged in the order of the Japanese syllabary, for example, and can be easily searched.

The area name information shown in FIG. 37 is for the case where the divided areas are set corresponding to the administrative boundaries as in the fourth embodiment. It is also assumed that the node data of the map information in the map information storage means 1 describes a divided area code to which the node belongs as shown in FIG.

Next, the operation of creating an optimum route will be described with reference to the flowchart of FIG. First, when the departure place is set by the point input means 3, the optimum route calculation means 4 calculates the coordinates of the departure place and the latitude and longitude of the node in the map information.
The node closest to the departure point is determined using the longitude, and is set as the departure point node (step ST381).

Next, the point input means 3 acquires the area name information from the map information storage means 1 and displays a list of the area names described in the area name information (step ST38).
2). When the occupant selects an appropriate area name in the displayed list as the destination area (step ST383), the point input means 3 acquires the area code corresponding to the selected area name from the area name information. Then, the divided area indicated by the area code is set as the destination area.

[0181] Optimal route calculation means 4 sets the departure point node as the inspection node (step ST384). Then, the area index information of the inspection node is searched from the map information storage means 1, and the route link is determined. Further, the next node connected to the inspection node by the link is determined (step ST385). The determined next node is temporarily stored in the optimum route data as one of the nodes constituting the optimum route (step ST386).

Then, it is determined whether or not the next node is a node in the destination area (step ST387). If the node is not within the destination area, the obtained next node is set as the inspection node (step ST388), and the processing of steps ST385 to ST387 is executed until the destination node is reached. If the node is within the destination area, the above-described optimal route calculation processing ends. The processing in steps ST384 to ST388 is performed in steps ST114 to ST11 in FIG.
8 is the same as the process of FIG.

When the calculation of the optimum route is completed, the optimum route calculating means 4 sends the optimum route data to the route information presenting means 5.
Hand over to The route information presentation means 6 reads the map information from the map information storage means 1 and displays the map on the display unit using the read map information. The route based on the optimal route data is displayed.

In this embodiment, the area names are displayed in a list so that the occupants can select the destination area. However, the point input means 3 displays a map on which the administrative boundaries are described and the destination area is displayed. You may make it select on a map.

Further, in this embodiment, the case where the point setting means for directly inputting the destination area is applied to the navigation apparatus according to the first embodiment has been described. A point setting means for inputting can also be applied. Further, the degree of ease of reaching not only the main road but also the general road is stored in the map information storage means 1, and the destination road is input by the occupant to calculate the optimal route to the destination road. You can also.

Embodiment 11 FIG. In each of the above embodiments, except for the seventh embodiment, the destination of the route calculation is a destination area having a certain area. Then, when the sequentially calculated routes reach the destination area, the optimum route calculation process is terminated.
The termination is inevitably brought about in executing the route calculation processing procedure. Further, as described in the seventh embodiment, a phenomenon may occur in which the calculated route deviates from the true optimal route as approaching the destination node. In order to minimize the influence of such a phenomenon, it is unavoidable to stop the route calculation when the route enters the destination area.

However, as described in the description of the tenth embodiment, when the destination is specified in a general area, the occupant does not always specify a clear point. Therefore, it may be better to present a route to a point representing the destination area without terminating the process when entering the destination point.

The navigation device according to this embodiment is
A route to a representative point in the destination area is presented.
For this purpose, the area index information describes the degree of ease of reaching a representative point selected in the destination area. The configuration of the navigation device according to this embodiment is the same as the configuration shown in FIG. 1, although the information set in the map information storage means 1 is different and the operation of the optimum route calculation means 4 is different.

FIG. 39 is an explanatory diagram showing an example of the area index information in this embodiment. In the figure, the contents of the left and center columns are the same as those shown in FIG. In the right column, the degree of ease of reaching a representative point selected in advance is described. The representative point is a representative point selected at the time of creating the area index information in the first embodiment. The procedure for creating each reachability is the same as the area index information creating procedure in the first embodiment. However, in the first embodiment, the reachability of each node to the divided area to which the node belongs is not described, but here, the node is excluded except when the node itself is a representative point. The degree of ease of reaching the representative point is described even in the divided area to which the user belongs.

FIG. 40 is an explanatory diagram showing a representative point information list used as auxiliary data of the area index information. The representative point information list is stored in the map information storage means 1 and describes the node number of the representative point and the area code indicating the divided area to which the representative point belongs. The node number is used to specify a representative point as a destination and to determine the stop of route calculation. The area code is used when the destination area is specified using the point input means 3 in the tenth embodiment.

Next, the operation of calculating the optimum route will be described with reference to the flowchart of FIG. First, when the departure place is set by the point input means 3, the optimum route calculation means 4 calculates the coordinates of the departure place and the latitude and longitude of the node in the map information.
The node closest to the departure point is determined using the longitude, and is set as the departure point node (step ST411).

Next, the latitude / longitude of each representative point is obtained from the node data in the map information using the node number described in the representative point information list. Then, by comparing them with the coordinates of the destination set by the point input means 3, the representative point closest to the destination is determined. The determined representative point is set as the destination representative point (step ST41).
2). Next, the departure point node is set as a check node (step ST413), and the next node forming the optimum route is determined with reference to the regional index information of the check node (step ST413).
414).

The processing of step ST414 is the same as that of the first embodiment shown in FIG. 12 except that the area index information to be processed is as shown in FIG. 39 and that the search key is the destination representative point. Processing is the same. That is, first, the first of the connection links connecting to the inspection node
Is a test link. Then, the area index information of the inspection link is obtained, and the degree of ease of reaching the destination representative point is extracted. If reachability is "1",
The link information of the inspection link is extracted from the map information in the map information storage means 1, and the start node and the end node are known from the link information. The node that is not the check node is the next node.

If the reachability is not “1”, it is determined whether or not the above processing has been performed for all the connection links. If the processing is not completed, the next connection link is set as the inspection link, and the above processing is executed.

The next node is determined as described above. When the next node is obtained, it is temporarily stored in the optimum route data (step ST415). Then, it is determined whether or not the node number of the next node matches the node number of the destination representative point (step ST416). If they do not match, the next node is set as a check node (step ST41).
7), perform the processing of steps ST414 to ST416. If the next node matches the destination,
The optimum route calculation processing ends.

When the calculation of the optimum route is completed, the optimum route calculating means 4 sends the optimum route data to the route information presenting means 5.
Hand over to The route information presentation means 6 reads the map information from the map information storage means 1 and displays the map on the display unit using the read map information. The route based on the optimal route data is displayed.

Embodiment 12 FIG. Although the first embodiment does not consider traffic regulations, the actual road network has traffic regulations such as one-way traffic and prohibition of right and left turns, and the presentation of an optimal route corresponding to the traffic regulations is required. When there is a link restriction such as one-way traffic, entry into the end node of the link from any direction may be prohibited. Therefore, when creating the regional index information, when searching for a route to the representative point, if the cost of the link in the impassable direction is set to infinity, when calculating the optimum route, it is possible to comply with the link traffic regulation. The optimum route can be calculated.

When there is a node traffic restriction such as a right / left turn prohibition or the like, the connection link to be discharged is different if the approach direction to the node is different. Therefore, in the area index information, the reachability of all the connection links that can become outflow links to a certain destination area according to the approach direction is set to the “easy to reach” state, and the node data is added to the node data of the map information. Prepare a traffic regulation code. When calculating the optimum route, the outgoing link that is determined to be “easy to reach”, the one permitted to pass by the node traffic control code is set as the route link. Thus, when calculating the optimum route, the optimum route corresponding to the node traffic regulation can be calculated.

FIG. 42 shows node data to which node traffic regulation is added. The format of the node data is a format widely used in a publicly available road map database. In the drawing, the (connection link) traffic regulation in the _ij direction indicates the traffic regulation when the node goes from the connection link i to the connection link j. For example, “0” is described if there is no traffic regulation, and “1” is described if there is traffic regulation. Traffic restrictions are described for all combinations of connecting links.

[0200] In the case where a degree of reachability such as "easy to reach" is given to a destination area in a plurality of link directions,
It is desirable to make a difference in the ease of reaching according to the link cost required to reach the destination area. By doing so, a route with lower cost can be selected when the right / left turn restriction is not imposed.

However, when such multi-value reachability is set in the area index information, there arises a problem that the data amount increases and the memory capacity required for the map information storage means 1 increases. The navigation device according to this embodiment suppresses the increase in the memory capacity by providing the area index information used in the first embodiment corresponding to the approach direction of the node. In other words, the optimal route is calculated by using the regional index information based on the binary ease of arrival while complying with the node traffic regulation. The configuration of the navigation device according to this embodiment is the same as the configuration shown in FIG. 1, although the information set in the map information storage means 1 is different and the operation of the optimum route calculation means 4 is different.

FIG. 43 is an explanatory diagram showing an example of the area index information used in this embodiment. As shown in FIG.
In the left column, the presence or absence of traffic regulation corresponding to the regional index information of each node is set. The node traffic regulation presence / absence is set to a value of “1” or “0”, and indicates the presence / absence of regulation at the node. The contents of the center column and the right column are information on the nodes having the node traffic regulation. In the center column and the right column, the regional index information shown in FIG. 7 is used for nodes without node traffic restrictions. If the format of the regional index information is changed depending on whether or not the node traffic is restricted, the entire data amount of the regional index information can be reduced.

In the center column of FIG. 43, the regional index information in the direction of connection link #i, #j of node (n) is the regional index in the direction of entering the node from connection link i and flowing out to connection link j. Information. Such type of regional index information describes the combination of all connection links at the node.

Next, the process of creating the regional index information shown in FIG. 43 will be described with reference to the flowchart of FIG. The processing in steps ST431 to ST434 is the same as that in FIG.
Is the same as the processing of steps ST91 to ST94 in. That is, first, an arbitrary node in the route calculation target area is selected (step ST431). Then, the node is set as a departure place (step ST432).

Next, an arbitrary divided area in the route calculation target area is selected as a destination area (step ST433).
Then, an appropriate node in the destination area is set as a representative point (step ST434). Further, one connection link of the departure point node is selected (step ST435). Then, if the selected link is an entry link to the node, a link that cannot be flown out due to the restriction of node traffic is temporarily excluded from the target road network for the route search (step ST436). Specifically, the link number of the excluded link is stored in the temporary memory.

A route search is performed between the departure point node and the representative point (step ST437). At this time, the excluded links are not searched. A link connected to the departure point node is obtained from the searched routes (step ST438). Next, the degree of ease of arrival of the destination area in the area index information of the departure point node in the direction from the ingress link selected in step ST435 to the link acquired in step ST438 is set to "1" (step ST439).

It is determined whether the above processing has been performed for all connection links (step ST440). If there is an unprocessed link, it is selected, and step ST436 is performed.
To ST440. When all the connection links are processed as the ingress links, the reachability of the area index information whose reachability is not "1" is set to "0" for the target divided area (step ST4).
42).

It is determined whether or not the above processing has been performed for all the divided areas (step ST443). If there is an unprocessed divided area, it is selected, and steps ST434 to S434 are performed.
The processing of T443 is performed. When processing has been performed for all divided areas, it is determined whether or not the above processing has been performed for all nodes (step ST445). If there is an unprocessed node, it is selected, and steps ST432 to ST432 are selected.
The process of T445 is performed. When the processing has been performed for all the divided areas, the area index information creation processing ends.

With the above processing, the regional index information shown in FIG. 43 is created. The created area index information is set in the map information storage unit 1. Note that the above process is a process for creating regional index information for a node having a node traffic regulation, and a process shown in the flowchart of FIG. 9 may be performed for a node having no node traffic regulation.

Next, the optimum route calculation processing will be described with reference to the flowchart in FIG. When the departure place and the destination are set, the optimum route calculation means 4 determines a node closest to the departure place, and sets the determined node as a departure place node (step ST4515). The node closest to the destination is set as the destination node (step ST45).
2) The destination area to which the destination node belongs is determined (step ST453).

Next, the starting point node is set as the inspection node (step ST454). Note that the above processing is performed in
Is the same as the processing of steps ST111 to ST114 in the above. Then, the route index is determined by searching the area index information of the inspection node from the map information storage means 1, and the next node connected to the inspection node by the link is determined (step ST455). The determination of the next node is executed as shown in the flowchart of FIG.

First, of the connection links connected to the check node, the first link is set as a check link (step ST4).
61). Then, regional index information is obtained in which the relay link is the entry direction and the inspection link is the outflow direction (step ST).
462), and the degree of ease of reaching the destination area is extracted (step ST463). However, if the inspection node is the departure node, the relay link is not determined, so the relay link is appropriately determined.

If the extracted ease of arrival is “1”,
The link information of the inspection link is extracted from the map information in the map information storage means 1 (steps ST464 and ST465).
The start node and the end node are known from the link information.
Since one of them is a check node, the other node different from the check node is set as the next node (step ST
466).

If the degree of reachability is not “1”, it is confirmed whether or not the above processing has been performed for all connected links, that is, whether or not the processing has been completed for that node (step ST467). If the processing is not completed, the next connection link is set as the inspection link (step ST468), and the processing of steps ST462 to ST464 is executed. When the processing is completed, it means that the route has reached a dead end before reaching the destination area. The above processing is the same as that of FIG. 12 except for the processing of step ST462.
Is the same as the processing of steps ST121 to ST126 shown in FIG.

As described above, the next node is determined.
The determined next node is temporarily stored in the optimum route data as one of the nodes constituting the optimum route (step ST).
456). Then, it is confirmed whether the determined next node is within the destination area (step ST457). If the route is within the destination area, the route has reached the vicinity of the destination, and the optimum route calculation process ends. If it is not within the destination area, the link from the inspection node to the next node is set as the relay link (step ST458), and the next node is set as the inspection node (step ST459), and the processing of steps ST455 to ST457 is executed. Note that the above processing is different from steps ST116 to ST116 in FIG. 11 except that the processing of step ST458 is added.
This is the same as the processing of T118.

When the calculation of the optimum route is completed, the optimum route calculating means 4 sends the optimum route data to the route information presenting means 5.
Hand over to The route information presentation means 6 reads the map information from the map information storage means 1 and displays the map on the display unit using the read map information. The route based on the optimal route data is displayed.

[0217]

As described above, according to the first aspect of the present invention, in the navigation device, the map information storage means makes it easy for each road segment to reach each of the plurality of divided areas constituting the route calculation target area. Holds regional index information indicating the degree,
Since the optimal route calculation means calculates the optimal route from the road junction near the starting point to the destination area using the respective degrees of reach, the time required for the route calculation is shorter than that of the conventional device. There is an effect that a shortened one can be obtained.

According to the second aspect of the present invention, in the navigation device, the map information storage means holds the degree of ease of arrival of each road segment to each of the divided areas where the adjacent areas have an overlapping portion, and the optimal route The calculation means determines one of the divided areas including the destination as the destination area, and calculates the optimum route from the road junction near the departure point to the destination area using the respective degrees of reach. Therefore, it is possible to calculate the optimum route for a destination area more appropriate for the occupant, and to present a more effective route for the occupant while maintaining the effect of the high speed of the processing according to the first invention. There is an effect that can be obtained.

According to the third aspect of the present invention, in the navigation device, the map information storage means includes the degree of reachability of each road segment connected to each road junction to each of the plurality of wide-area division areas and the road junction. Holds the regional index information indicating the degree of reach of each road segment to each of the narrow divided areas constituting the wide divided area, and the optimum route calculation means performs the calculation from the road branch point near the departure point in the wide divided area. The optimal route to a certain destination area is calculated using each degree of reach, and the optimal route to the destination area, which is a narrow divided area near the destination, is calculated using each degree of reach. Therefore, the memory amount does not increase so much even if the route calculation target range is widened, and further, there is an effect that a detailed route can be presented in the vicinity of the destination desired by the occupant.

According to the invention described in claim 4, in the navigation device, the map information storage means holds area index information indicating the degree of reach of each road segment to each of the divided areas corresponding to the administrative division area, Since the optimal route calculation means calculates the optimal route from the road junction near the departure point to the destination area using the respective degrees of reach, the periphery of the outline of the destination area has a low road density. There is an effect that the possibility that the degree of deviation between the calculated final point of the route and the objective can be reduced while maintaining the effect of the high speed of the processing according to the first invention is increased.

According to the fifth aspect of the present invention, in the navigation device, the map information storage means holds area index information indicating the degree of reach of each road segment connected to each main road to each of the divided areas. Since the optimum route calculation means calculates the optimum route from the road branch point of the main road near the departure point to the destination area by using the respective degrees of reach, the processing speed according to the first invention is high. There is an effect that the memory amount can be further reduced while maintaining the above effect.

According to the invention of claim 6, in the navigation device, the map information storage means holds area index information indicating the degree of ease of arrival of each road segment to each of the main roads, and the optimum route calculation means Since the optimal route from the road junction near the departure point to the target arterial road is calculated using the respective degrees of reach, the amount of memory can be reduced, and the trunk line that is likely to be desired by the occupants is high. There is an effect that a route that leads to a road can be quickly presented.

According to the seventh aspect of the present invention, in the navigation device, the map information storage means holds area index information indicating the ease of arrival of each road segment to each of the divided areas, and the optimum route calculation means The optimum route from the road junction near the departure point to the vicinity of the destination area is calculated using each ease of arrival, and the optimum route from the vicinity of the destination area to the vicinity of the destination is obtained by graph search processing. Therefore, it is possible to obtain a route capable of presenting a detailed route in the vicinity of the destination desired by the occupant while reducing the time required for calculating the optimum route as a whole.

[0224] According to the invention described in claim 8, the navigation device displays the portion of the optimum route calculated by the optimum route calculation means within the range where the real-time traffic information is effective in a graph in which the real-time traffic information is added. Since the configuration is such that the route is replaced with the optimal route by the search process, while maintaining the effect of the high speed of the process according to the first invention,
There is an effect that a route that can present a route more suited to the actual traffic condition can be obtained.

According to the ninth aspect of the present invention, in the navigation device, the map information storage means includes information on the correspondence between the road branch points and the divided areas, and the ease with which each road segment can reach each of the divided areas. And the optimal route calculation means calculates the optimal route from the road junction near the departure point to the destination area using the corresponding information and the respective degrees of reach. Thus, there is an effect that a target area can be recognized more quickly, and the processing speed can be further increased.

According to the tenth aspect of the present invention, in the navigation device, the map information storage means stores the area index information indicating the ease of reaching each road segment to each of the divided areas or the ease of reaching each of the roads. The point setting means directly sets the destination area or the destination road, and the optimum route calculation means calculates the optimum route from the road junction near the departure point to the destination area or the destination road by using the respective degrees of reach. With this configuration, there is an effect that the destination setting operation can be simplified and the route calculation processing can be speeded up.

According to the eleventh aspect of the present invention, in the navigation device, the map information storage means holds area index information indicating the degree of reach of each road segment to each of the representative points in each divided area, and Since the calculation means calculates the optimal route from the road junction near the departure point to the representative representative point using each degree of reach, the crew requesting the route to the point representing the destination area is requested. And the speed of the route calculation process can be increased.

According to the twelfth aspect of the present invention,
In the navigation device, the map information storage means stores area index information in which the degree of reach of each road segment to each of the divided areas is set according to the approach direction to each road junction, and the optimal route The calculation means calculates the optimum route from the road junction near the departure point to the destination area by using the respective degrees of reach corresponding to the approach directions.
The present invention has an effect that a more appropriate route can be presented in consideration of traffic regulation while maintaining the effect of high-speed processing.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a navigation device according to one embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a configuration example of a point input unit.

FIG. 3 is a configuration diagram illustrating a configuration example of a route information presentation unit.

FIG. 4 is an explanatory diagram showing a display example in a route information presentation unit.

FIG. 5 is an explanatory diagram showing an example of map information.

FIG. 6 is an explanatory diagram showing an example of a map.

FIG. 7 is an explanatory diagram showing an example of area index information.

FIG. 8 is an explanatory diagram showing how the reachability is set.

FIG. 9 is a flowchart illustrating a process of creating area index information.

FIG. 10 is an explanatory diagram showing another example of the area index information.

FIG. 11 is a flowchart showing an optimum route calculation process of the navigation device according to the first embodiment of the present invention.

FIG. 12 is a flowchart showing a next node determining process during the process shown in FIG. 11;

FIG. 13 is an explanatory diagram showing an example of a map.

FIG. 14 is an explanatory diagram showing an example of area division according to the second embodiment of the present invention.

FIG. 15 is a flowchart showing a destination area candidate setting process of the navigation device according to the second embodiment of the present invention.

FIG. 16 is a flowchart showing a destination area selection process of the navigation device according to the second embodiment of the present invention.

FIG. 17 is an explanatory diagram showing wide area division and narrow area division.

FIG. 18 is an explanatory diagram showing an example of area index information corresponding to wide area division and narrow area division.

FIG. 19 is a flowchart illustrating a next node determination process of the navigation device according to the third embodiment of the present invention.

FIG. 20 is an explanatory diagram showing an example of area division according to the fourth embodiment of the present invention.

FIG. 21 is an explanatory diagram showing regional index information according to a fourth embodiment of the present invention.

FIG. 22 is an explanatory diagram showing administrative boundary data.

FIG. 23 is an explanatory diagram showing a method of determining whether a node is inside or outside a polygonal divided area.

FIG. 24 is a flowchart showing an optimum route calculation process of the navigation device according to the fifth embodiment of the present invention.

FIG. 25 is an explanatory diagram showing an example of a map.

FIG. 26 is an explanatory diagram showing an example of main road information.

FIG. 27 is a flowchart showing a process of creating main road information.

FIG. 28 is a flowchart showing an optimum route calculation process of the navigation device according to the sixth embodiment of the present invention.

FIG. 29 is a flowchart showing a destination road determination method during the processing shown in FIG. 28;

FIG. 30 is a flowchart showing an optimum route calculation process of the navigation device according to the seventh embodiment of the present invention.

FIG. 31 is a block diagram showing a configuration of a navigation device according to an eighth embodiment of the present invention.

FIG. 32 is an explanatory diagram showing an example of the format of traffic information data.

FIG. 33 is a flowchart showing an optimum route calculation process of the navigation device according to the eighth embodiment of the present invention.

FIG. 34 is an explanatory diagram for explaining replacement of an optimum route.

FIG. 35 is a flowchart showing a graph search process in the traffic information applicable range.

FIG. 36 is an explanatory diagram showing an example of map information in the navigation device according to the ninth embodiment of the present invention.

FIG. 37 is an explanatory diagram showing an example of area name information.

FIG. 38 is a flowchart showing an optimum route calculation process of the navigation device according to the tenth embodiment of the present invention.

FIG. 39 is an explanatory diagram showing regional index information in the navigation device according to the eleventh embodiment of the present invention.

FIG. 40 is an explanatory diagram showing a representative point information list.

FIG. 41 is a flowchart showing an optimum route calculation process of the navigation device according to the eleventh embodiment of the present invention.

FIG. 42 is an explanatory diagram showing node data to which node traffic restrictions are added;

FIG. 43 is an explanatory diagram showing regional index information in a navigation device according to a twelfth embodiment of the present invention.

FIG. 44 is a flowchart showing a process of creating the area index information shown in FIG. 43.

FIG. 45 is a flowchart showing an optimum route calculation process of the navigation device according to the twelfth embodiment of the present invention.

FIG. 46 is a flowchart showing a next node determination method during the processing shown in FIG. 45;

FIG. 47 is a block diagram showing a configuration of a conventional navigation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Map information storage means 2 Current position detection means (point setting means) 3 Point input means (point setting means) 4 Optimal route calculation means 5 Route information presenting means 6 Traffic information receiving means

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-34169 (JP, A) JP-A-5-27678 (JP, A) JP-A-4-88600 (JP, A) JP-A-4-34 319619 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01C 21/00-21/24 G08G 1/0969

Claims (12)

(57) [Claims] 1. Map information including information on each road junction and information on a road segment connecting the road junctions, and easy access of each road segment to each of a plurality of divided regions constituting a route calculation target region. Map information storage means having area index information indicating the degree, a point setting means for setting a departure place and a destination, and a road branch point near the departure place set by the point setting means by using the map information. In addition to the determination, the divided area including the destination set by the point setting means is determined as the destination area, and the optimum route from the road junction near the departure point to the destination area is determined in each of the area index information. A navigation system comprising an optimum route calculating means for calculating using the reachability, and a route information presenting means for presenting the optimum route calculated by the optimum route calculating means. Device. 2. Map information including information on each road junction and information on a road segment connecting the road junctions, and a plurality of adjacent regions constituting a route calculation target region having overlapping portions. Map information storage means having area index information indicating the degree of accessibility of each road segment to each of the divided areas; point setting means for setting a departure place and a destination; and a departure place set by the point setting means. A nearby road junction is determined using the map information, and one of the divided areas including the destination set by the point setting means is determined as a destination area, and a road near the departure point is determined. Optimum route calculation means for calculating the optimum route from the branch point to the destination area using the respective degrees of reach in the area index information, and the optimum route calculation means A navigation device provided with route information presenting means for presenting an optimal route. 3. Map information including information on each road junction and information on a road segment connecting the road junctions, and each road junction to each of a plurality of wide area divisions constituting a route calculation target area. Map information storage means having area index information indicating the ease of arrival of each road segment to each of the narrow-area sub-areas constituting the wide-area sub-area including the road branch point and the ease of arrival of each road-section to be connected; A point setting means for setting a starting point and a destination,
A road branch point near the departure point set by the point setting means is determined using the map information, and a wide area division area including the destination set by the point setting means is determined as the destination area. The optimum route from the road junction near the departure point to the destination area is calculated by using the respective degrees of reach in the area index information, and when the optimum route reaches the destination area, a narrow area division including the destination is performed. An optimal route calculating means for calculating an optimal route to the destination area by using each reachability in the area index information with the area as a new destination area, and an overall optimal route calculated by the optimal route calculating means. Navigation device provided with a route information presenting means. 4. Map information including information on each road junction and information on a road segment connecting the road junctions, and a plurality of regions constituting a route calculation target region, the divided regions corresponding to an administrative division region. , Map information storage means having area index information indicating the ease of arrival of each road segment to each of the above, a point setting means for setting a departure place and a destination, and a vicinity of the departure place set by the point setting means. The road junction is determined using the map information, and the divided area including the destination set by the point setting means is determined as the destination area, and the road junction from the road junction near the departure point to the destination area is determined. An optimal route calculating means for calculating an optimal route by using the respective degrees of reach in the area index information; and a route for presenting the optimal route calculated by the optimal route calculating means. A navigation device comprising information presenting means. 5. Map information including information on each road junction and information on a road segment connecting the road junctions, and connecting to each of the main roads to each of the plurality of divided areas constituting the route calculation target area. Map information storage means having area index information indicating the degree of ease of arrival of each road segment, point setting means for setting a departure place and a destination, and a main road near the departure place set by the point setting means A branch point is determined using the map information, a divided area including the destination set by the point setting means is determined as the destination area, and the target area is determined from a road branch point of a main road near the departure point. An optimal route calculating means for calculating an optimal route to the route using the respective degrees of reach in the area index information, and an optimal route calculated by the optimal route calculating means. Navigation device provided with route information presenting means. 6. Map information including information on each road junction and information on road segments connecting the road junctions, and regional index information indicating the ease of arrival of each road segment on each of the main roads. Map information storage means, a point setting means for setting a departure point and a destination arterial road, and a road junction near the departure point set by the point setting means is determined using the map information, An optimal route calculating means for calculating an optimal route from a road branch point in the vicinity of the destination to the target arterial road by using the respective degrees of reach in the area index information, and an optimal route calculated by the optimal route calculating means. A navigation device provided with route information presentation means. 7. Map information including information on each road junction and information on a road segment connecting the road junctions, and easy access of each road segment to each of a plurality of divided regions constituting a route calculation target region. Map information storage means having area index information indicating the degree, a point setting means for setting a departure place and a destination, and a road branch point near the departure place set by the point setting means by using the map information. In addition to the determination, the divided area including the destination set by the point setting means is determined as the destination area, and the optimum route from the road junction near the departure point to the vicinity of the destination area is determined in the area index information. Means for calculating the optimal route from the vicinity of the destination area to the vicinity of the destination by graph search processing, And a route information presenting means for presenting the entire optimal route by the optimal route calculating means. 8. A traffic information receiving device for receiving real-time traffic information, wherein the optimum route calculating means receives a portion of the calculated optimum route within a range where the real-time traffic information is valid, by the traffic information receiving device. 7. The navigation device according to claim 1, wherein the navigation device replaces the real-time traffic information with an optimal route obtained by a graph search process. 9. A map including information on each road junction, information on a road segment connecting the road junctions, and correspondence information on the correspondence between each road junction and each of the divided areas constituting the route calculation target area. Information, map information storage means having area index information indicating the ease of arrival of each road segment to each of the divided areas, point setting means for setting a starting point and a destination, and setting by the point setting means. The road branch point near the departure point is determined using the map information, and the divided area including the destination set by the point setting means is determined as the destination area, and the road branch point near the departure point is determined. Optimal route calculation means for calculating an optimal route from a point to the destination area using the corresponding information in the map information and the respective degrees of reach in the area index information, A navigation device provided with route information presenting means for presenting the optimum route calculated by the optimum route calculating means. 10. Map information including information on each road junction and information on a road segment connecting the road junctions, and ease of arrival of each road segment to each of a plurality of divided areas constituting a route calculation target area. Map information storage means having area index information indicating the degree of accessibility of each road segment to each road or each road, and a point for setting a destination area or a destination road which is one of the departure place and the divided area Setting means for determining a road junction near the departure point set by the point setting means using the map information, and an object set by the point setting means from the road junction near the departure point. An optimum route calculating means for calculating an optimum route to an area or a destination road by using the respective degrees of reach in the area index information; And a route information presenting means for presenting the optimal route calculated by the navigation device. 11. Map information including information on each road junction and information on a road segment connecting the road junctions, and each road segment to each of the representative points in a plurality of divided regions constituting the route calculation target region. Map information storage means having area index information indicating the degree of ease of arrival, a point setting means for setting a departure place and a destination, and a road branch point near the departure place set by the point setting means. And the representative point of the divided area including the destination set by the point setting means is determined as the destination representative point, and the optimal route from the road junction near the departure point to the destination representative point is determined. Route calculation means for calculating the optimal route calculated by using the respective degrees of reach in the regional index information, and a process for presenting the optimum route calculated by the optimum route calculation means. A navigation device provided with road information presentation means. 12. A road having map information including information on each road junction and information on a road segment connecting the road junctions, and each of the roads to each of a plurality of divided areas constituting a route calculation target area Map information storage means having area index information in which the degree of ease of intercept is set according to the approach direction to each road fork; point setting means for setting a departure place and a destination; A road branch point near the departure point set by the means is determined using the map information, and a divided area including the destination set by the point setting means is determined as a destination area, and the vicinity of the departure point is determined. Optimal route calculating means for calculating an optimal route from the road branch point to the destination area using each reachability corresponding to the approach direction in the area index information,
A navigation device provided with route information presenting means for presenting the optimum route calculated by the optimum route calculating means.