JPH07272197A - Intersection guiding device - Google Patents

Abstract

PURPOSE:To provide an intersection guiding device which correctly executes guidance to a road to progress without using a storage device of a large capacity even in the case where plural intersections exist very close to the intersection to be route-guided. CONSTITUTION:A road map memory 7 stores link data concerning going-in link and a going-out link by mutual correspondence. When the going-out link contains a route code address, it contains the route code address, too. When a vehicle goes in the going-in link of the intersection to be route-guided, the route code address is reported together with a direction to go if the route code address is contained in the going-out link to be reported. Since the route code address is mainly constituted by numerals, it can be stored in a storage device of a small capacity. Since a driver can recognizes a guide sign where the route code address in written, by eyes, it is easily judged which road is to go even in the case where plural intersections exist.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intersection guide device for a navigation device mounted on a vehicle, which guides the road on which the vehicle should travel when the vehicle reaches the vicinity of the intersection where the route should be guided.

[0002]

2. Description of the Related Art Conventionally, a navigation device has been mounted on a vehicle and used in order to assist the vehicle traveling on an unguided land. In such a navigation device, the CPU is based on the traveling distance and traveling direction of the vehicle detected by the distance sensor and the direction sensor, respectively.
The current position of the vehicle is detected by a control unit including the (central processing unit), and the detected current position of the vehicle is displayed on a display device composed of a CRT or a liquid crystal display element together with a road map around the vehicle. . The road map data is generally stored in the road map memory.

In addition, according to the setting of the destination by the driver, the route calculation road map data of the range including the departure place (current position) and the destination is read from the road map memory, and the read route calculation road is read. There is also known a method of calculating an optimum route from a starting point to a destination based on map data (see Japanese Patent Laid-Open No. 2-277200). The calculated optimum route is displayed, for example, in a dotted line, on the road when the road map is displayed on the display device.

However, in such a conventional navigation device, the driver visually recognizes a mark of a small vehicle on the screen and a display of a narrow optimum route while driving, and therefore, the driver visually recognizes when approaching an intersection, especially when driving in an urban area. Doing this is not preferable for traffic safety. Therefore, when an intersection near which the vehicle should pass is approached, the driver is informed by voice of the direction in which the vehicle should proceed, and a large arrow indicating the traveling direction is displayed so as to correspond to the shape of the intersection. Has been proposed (see, for example, JP-A-64-16916). In the device disclosed in this publication, various kinds of information are provided by voice and images, so that the driver can obtain the information while gazing ahead or by simply glancing at the screen. . Therefore, it is possible to improve traffic safety.

[0005]

However, in the above-mentioned prior art, there is a problem in that when a plurality of intersections are in the immediate vicinity of the intersection to be route-guided, it cannot be handled.
That is, in the above prior art, when notifying by voice,
It is simply announced by a simple voice such as "Next branch is right" or "Next branch is left".
Therefore, for example, as shown in FIG.
If the exit ramp L1 from and the entrance C1 of the connecting road from the highway R1 to the other highway R2 are in the immediate vicinity, as a voice, "the next branch is to the left"
Is output, and it is difficult for the driver to quickly determine from which to turn left.

This is also the case when the shape of an intersection is displayed using an arrow. Therefore, in order to deal with this, a method of notifying the destination name etc. written on the guide sign installed on the road by voice or display can be considered. According to this method, after being notified, the driver can determine which intersection the guide is for by visually recognizing the destination name written on the guide sign actually installed.

However, this method has a problem that an extremely large-capacity storage device is required because all destination names and the like written on the guide sign must be stored. Therefore, the purpose of the present invention is to
Provided is an intersection guidance device which solves the above technical problem and can accurately guide a road to be advanced without using a large-capacity storage device even when there are a plurality of intersections in the immediate vicinity of the intersection to be route-guided. It is to be.

[0008]

An intersection guidance device of the present invention for achieving the above object has a function of calculating an optimum route and storing it in a route storage means, and should provide route guidance specified in advance. Along with the link data about the link entering the intersection and the link data about the link leaving the intersection, if the exit link has a route code, the route code is stored in association with the link data. The intersection guidance data storage means, the judgment means for judging whether the vehicle has reached the link entering the intersection, or the predetermined distance from the intersection, and the judgment means. As a result of the judgment, if it is judged that the vehicle has reached the link entering the intersection or has approached a predetermined distance from the intersection, the above Based on the link data relating to the link entering the intersection and the link data relating to the link leaving the intersection stored in the difference guidance data storage means, the link to be exited by the vehicle is specified, and the link to be exited is specified. When the line abbreviation is attached, it is characterized by including notifying means for notifying the line abbreviation.

Here, the above-mentioned link is a vector connecting nodes representing coordinate positions for specifying road intersections and the like.

[0010]

In the above structure, it is determined whether or not the vehicle has reached the link entering the intersection, or whether or not the vehicle has approached the intersection by a predetermined distance. This determination is based on, for example, the current position of the vehicle detected by the position detecting means,
This is performed based on the optimum route stored in the route storage means and the link data relating to the link entering the intersection stored in the intersection guidance data storage means. As a result of the above judgment, the vehicle reached the link entering the intersection,
Alternatively, when it is determined that the vehicle has approached the intersection by a predetermined distance, the vehicle exits based on the link data regarding the link entering the intersection and the link leaving the intersection stored in the intersection guidance data storage means. The link to be specified is specified. Then, when a line code is attached to the specified link to be exited, the line code is notified by the notification means.

Here, the above-mentioned route abbreviation is composed of numbers and alphabets attached to each route such as the Metropolitan Expressway and the Hanshin Expressway, and is installed on the road just before the intersection. It is also written on the sign. In this way, according to the above configuration, the driver can easily determine the road on which the vehicle should travel by visually recognizing the guide sign having the route code after the notification. In addition, the capacity required to store the route code is small because the route code is composed of numbers and the like. Therefore, even when there are a plurality of intersections in the immediate vicinity of the intersection to be route-guided, the traveling direction can be accurately guided without using a large-capacity storage device.

[0012]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of a navigation system of an embodiment to which an intersection guidance device of the present invention is applied. This navigation system is used by being mounted on a vehicle, and is based on the outputs of a distance sensor 1 for detecting the traveling distance of the vehicle, a direction sensor 2 for detecting the traveling direction of the vehicle, and a geomagnetic sensor 3 for detecting the earth's magnetic field. Then, the current position of the vehicle is detected by a position detecting device 4 which is a position detecting means, and the detected current position is displayed by a display device 5 including a CRT, a liquid crystal display element or the like.
It is designed to be displayed together with the road map around it. That is, when the current position of the vehicle detected by the position detection device 4 is given to the controller 6, the controller 6 causes the road map memory 7 configured by a CD-ROM to pass a constant value near the current position via the memory drive 8. The road map data of the range is read, and the current position is superimposed on the read road map and displayed on the display device 5.

In the present embodiment, the controller 6 is
Functions as a road map data reading means, a route calculating means, a route storing means, a judging means, and the like. The detection of the current position by the position detection device 4 is basically performed by the distance sensor 1
And so-called self-contained navigation based on the output of the direction sensor 2. That is, the position detection device 4 integrates the output of the distance sensor 1 over a predetermined time and also integrates the output of the azimuth sensor 2 during the predetermined time. As a result, the traveling distance of the vehicle in the predetermined time is obtained from the integrated value of the distance sensor 1, and the traveling azimuth is obtained from the integrated value of the azimuth sensor 2. Therefore, for example, if you input the exact position of the vehicle before starting the vehicle,
Subsequent changes in the position of the vehicle can be detected.

For detecting the current position in the position detecting device 4, a so-called map matching method using the position detecting road map data stored in the road map memory 7 (for example, Japanese Patent Laid-Open No. 63-148115). , Japanese Unexamined Patent Publication No. 64-53112). That is, the current position is corrected to a position on the road in the vicinity thereof by utilizing the fact that the position of the vehicle is limited to the road in principle, and the current position is corrected to the road. As a result, it is possible to prevent the error of the current position detected based on each output of the distance sensor 1 and the azimuth sensor 2 from being accumulated, and improve the accuracy of position detection.

A beacon receiver 9 is connected to the position detecting device 4. The beacon receiver 9 is for receiving data such as position information and road information (intersection name, destination guidance, traffic jam information, accident information) radiated from a beacon antenna installed on the roadside or the like. The road information received by the beacon receiver 9 is given to the controller 6 and finally displayed on the display device 5.

The position detecting device 4 also includes a GPS (Global
Positioning System) The receiver 10 is connected.
The GPS receiver 10 receives radio waves transmitted from GPS satellites that are orbiting the earth. The position detecting device 4 directly detects the current position of the vehicle based on the propagation delay time of the received radio wave. In the position detection device 4, the current position obtained by the self-contained navigation, the current position obtained based on the position information received by the beacon receiver 9 or the radio wave received by the GPS receiver 10 is obtained. One of the current positions is selectively adopted according to a predetermined standard.

The road map memory 7 stores road map data for display, road map data for position detection, and road map data for route calculation. The road map data for route calculation is composed of link data. This link data includes the link number, the coordinates of the start node and end node of the link, the distance of the link, the absolute direction of the link, the average time required to drive this link, the type or type of road (general road link or highway). Link), road width, route abbreviation if this link has an abbreviation, and if the end node is a main intersection, its intersection name,
And so on.

Here, the node is a coordinate position for identifying an intersection or a bending point of a road, and the link is a vector connecting the nodes. The above-mentioned route abbreviation is a common name given to urban highways such as the Shuto Expressway, the Hanshin Expressway, national roads, and prefectural roads. For example, the “11” of the Hanshin Expressway No. 11 Ikeda Line.
It corresponds to "No. 1" on National Route 1. This route code is generally displayed on a guide sign actually installed on the road before the intersection. FIG. 2 shows an example of this guide sign. In this Figure 2, the route code is "C
It is indicated by "1", "3", and "4".

An example of the above road map data for route calculation is shown in Table 1 below.

[0020]

[Table 1]

In Table 1, l ₁ , l _2a , l _2b , l
_3a , l _3b , l _3c, etc. represent the links shown in FIG. 3, and the same applies hereinafter. Further, as can be seen from Table 1 above, the route calculation road map data is stored as a table in which the link data regarding the exit link and the link data regarding the approach link are associated with each other. Here, the exit link is a link 22 through which the vehicle 20 exits from the intersection 21, as shown in FIG. 4, and the entry link is a link 2 through which the vehicle 20 enters the intersection 21.
It is 3.

The route calculation road map data is
Since the exit link and the entry link are stored as a table in which they are associated with each other, if the link is a polygonal line link that is bent in the middle, the absolute direction of the link included in the above link data is Different depending on whether it is stored as a link or an incoming link. That is, when the polygonal line link is stored as the leaving link, the absolute direction of the link is as shown in FIG. 5 (a), the starting point node 24 and the minute distance r1 from the starting point node 24 along the leaving link 25. It corresponds to the absolute direction of a line 27 (indicated by a broken line in the figure) that connects the point 26 that has advanced only by, and when a polygonal line link is stored as an ingress link, the absolute direction of the link is as shown in FIG. As shown in FIG. 3, the end point node 28 and the point 3 that has returned from this end point node 28 along the approach link 29 by a minute distance r2.
It corresponds to the absolute azimuth of a line 31 (indicated by a broken line in the figure) connecting 0 and 0.

Returning to FIG. 1, the road map memory 7 also has an intersection guidance table in which link data relating to an entrance link relating to an intersection to which route guidance is to be preset and link data relating to all exit links are associated with each other. Is remembered. That is, the road map memory 7 also functions as intersection guidance data storage means. Table 2 below shows an example of this intersection guidance table.

[0024]

[Table 2]

The controller 6 is connected to an input device 11 for selecting various functions and a voice output device 12 for outputting a voice at the time of route guidance, which will be described later. The voice output device 12 and the display device 5 function as a notification means in this embodiment. The controller 6 is also provided with a voice data memory 13 composed of a ROM (Read Only Memory) in which voice data to be output when guiding the route is stored as a voice data table. Table 3 below shows an example of the audio data table. In Table 3, "No. 1,""No.2," and "C1" are route abbreviations, and A is an address.

[0026]

[Table 3]

FIG. 6 is a functional block diagram of the controller 6. The controller 6 is provided with a route guidance processing unit 61 that functions as the center of operation of the controller 6. The current position data of the vehicle is given from the position detecting device 4 to the route guidance processing unit 61, and when the current position data is given to the route guidance processing unit 61, the current position data is given to the road map memory control unit 62. The road map data for display around the current position is read from the road map memory 7 (see FIG. 1) via the memory drive 8. The read display road map data and the current position data that have been read are given to the display control unit 63, processed into display data, and then given to the display device 5. As a result, the display device 5 displays the current position of the vehicle in an overlapping manner on the road map.

The route guidance processing unit 61 includes an input control unit 64.
The input device 11 is connected via. Input device 11
When a route calculation request signal and destination data are given from the input control unit 64, the route guidance processing unit 61 causes the road map memory control unit 62 to read the road calculation road map data from the road map memory 7. The route calculation road map data, the destination data and the current position data thus read are given to the route calculation processing unit 65. Route calculation processing unit 65
Then, the optimum route to the destination is calculated by the Dijkstra method, for example, based on the given route calculation road map data, the destination data and the current position data.

In the Dijkstra method, the node or link closest to the destination (may be the current location) is the start point, the node or link closest to the current location (may be the destination) is the end point, and the link from the start point to the end point is This is a method of assuming a tree and sequentially adding all link costs (link travel time and travel distance) that form the tree, and selecting only the route with the lowest link cost that reaches the end point (Shibata, Tenmoku, Shimoura "Development of Stochastic Route Search Algorithm" Sumitomo Electric No. 143, p.165, 1
See September 993).

When the optimum route is calculated, the route guidance processing unit 61 gives the calculated optimum route to the display control unit 63 and also creates a guide table representing the calculated optimum route. The created guidance table is RAM
Stored in 66. Assuming that the optimum route calculated above is connected with the links l ₁ , l _2a , l _3c , ... Shown by solid lines in FIG. 3, an example of this guidance table is shown in Table 4 below. In Table 4, the traveling direction of the vehicle is indicated by arrow K.
(See FIG. 3) direction.

[0031]

[Table 4]

In the display controller 63, the given optimum route is processed into display data, and the processed display data is given to the display device 5. As a result, on the display device 5, the optimum route is displayed by, for example, a dotted line. 67
Is a voice control unit for reading from the voice data memory 13 the voice content to be output at the time of the route guidance processing described later and giving the read voice content to the voice output device 12.

FIG. 7 is a flow chart showing the route guidance processing in the controller 6. This route guidance process is performed to guide the vehicle so that the vehicle can reach the destination along the optimum route. When the optimum route is calculated in the route calculation processing unit 65 and the guidance table representing the calculated optimum route is stored in the RAM 66 (step S1), the route guidance processing unit 61
The intersection guidance table (see Table 2) stored in the road map memory 7 is read out via the road map memory control unit 63 and stored in the RAM 66 (step S2). At the same time, the route guidance processing unit 61 starts monitoring whether or not the vehicle is traveling on the optimum route, based on the guidance table stored in the RAM 66 and the current position data provided from the position detection device 4 (step S3). . When the vehicle deviates from the optimum route during this monitoring, the route guidance processing unit 61 ends this route guidance process. On the other hand, while the vehicle is traveling on the optimum route, it is always determined based on the intersection guidance table stored in the RAM 66 whether or not the vehicle has reached the approach link to the intersection to be route-guided. (Step S4). The process in step S4 may be, for example, a process of determining whether or not the vehicle has approached a predetermined distance R (for example, R = 500 (m)) from an intersection to be route-guided.

When the route guidance processing unit 61 determines that the vehicle has entered the approach link to the intersection to be route guided, the route guidance processing unit 61 selects the vehicle from the plurality of exit links stored in the intersection guidance table based on the guidance table. Specifies the exit link to be advanced, and performs the following processing to guide the vehicle to the specified exit link. That is, the route guidance processing section 61 first determines whether or not the identified exit link includes a route code by referring to the intersection guidance table (step S5), and as a result, the route code is included. If not, the usual route guidance is performed as usual (step S6), and if the route abbreviation is included, route guidance using the route abbreviation is performed (steps S7, S).
8).

To describe the ordinary route guidance in more detail, the route guidance processing section 61 causes the display control section 63 to display each absolute azimuth data included in the entry link data and the exit link data stored in the intersection guidance table. give. In order to correspond to each of the given absolute orientations, the display control unit 63 deforms an arrow, which is a deformed shape diagram of the intersection to be route-guided, that is, even if the intersection shape is not accurate, as shown in FIG. It is displayed on the display device 5 using the arrow that is made clear. In the route guidance processing unit 61,
Since the direction in which the vehicle should travel is recognized based on the absolute direction of the approach link and the absolute direction of the exit link specified above, only the arrow representing the specified exit link is conspicuous, for example, the display color. To be displayed. The display data for displaying the deformed arrow is stored in a memory (not shown) of the display control unit 63.

At the same time, the route guidance processing section 61 causes the voice control section 67 to obtain the corresponding voice content from the plurality of voice content stored in the voice data memory 13, and causes the voice output device 12 to obtain this. Output audio content. For example, if the absolute direction of the exit link that the recognized vehicle should travel to is to the right of the absolute direction of the approach link, the voice control unit 67 outputs the addresses "1" and "m" from the voice data memory 13. The audio contents corresponding to each (see Table 3) are acquired and given to the audio output device 12. As a result, the voice output device 12 outputs a voice such as “Turn right at the next branch”.

Next, route guidance using route abbreviations will be described more specifically. The route guidance processing unit 61 first
It is determined whether or not the same route code as the route code attached to the specified exit link is attached to another exit link by referring to the intersection guidance table (step S7),
If it is also attached to another exit link, it is expected that the driver will get lost when notifying, so the above-mentioned normal route guidance is performed. On the other hand, if the same exit code is not attached to other exit links, the same deformed arrow as in the above normal route guidance will be displayed, and the code indicating the exit code included in the exit link data will also be displayed. To be done. As for the symbol representing this route abbreviation, only its frame is stored in advance in a memory (not shown) of the display control unit 63, and the numbers or alphabets read by the route guidance processing unit 61 from the intersection guidance table are put in the frame. It is created by

FIG. 9 shows an example of a display screen when this route code is also displayed. In FIG. 9, the line abbreviations 40 and 41 on which the vehicle should travel have a double frame so that the driver can visually recognize the line by simply glancing. Further, "Tanimachi IC", "Tatsumi IC", etc. are the names of the end nodes of the entrance links, that is, the names of the intersections, and the names of the intersections are stored in the entrance link data of the intersection guidance table as described above.

Further, the voice output from the voice output device 12 in the route guidance using the route abbreviation is, for example, "Next" which is a combination of voice contents corresponding to the addresses "1" and "2" of the voice data table. The branch is in direction 9 ”. After being notified in this way, the driver has a guide sign (see FIG. 2) installed on the road marked with the same route code as the informed route code.
By visually recognizing, it is possible to easily determine which intersection the above notification is related to.

The above route guidance processing is performed until the vehicle reaches the destination (step S9). As described above, according to the navigation device of the present embodiment, when the road in the direction in which the vehicle should travel includes the route code, the route guidance is performed using the route code. Therefore, even when there are a plurality of intersections in the immediate vicinity, the driver can proceed to the road that should be traveled by visually recognizing the guide sign on which the same line abbreviation as the notified route abbreviation is written. . Therefore, it is possible to travel accurately to the destination.

Further, since the route abbreviation is composed of only numbers or a combination of numbers and alphabets, it can be stored in a storage device having a small capacity. Therefore, the cost can be reduced as compared with the case where the destination name is stored. In the route guidance using the route abbreviation, both the deformed arrow indicating the shape of the intersection and the route abbreviation are displayed, but only the route abbreviation may be displayed. Even when only the route code is displayed, the driver can determine the road to proceed by visually recognizing the guide sign.

Although only the route abbreviation is output as voice, for example, "The next branch is in the 9th direction", the route abbreviation is output, for example, "The next branch is the 9th direction left turn". In addition to the above, the direction in which the vehicle should proceed may be output as voice. Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in the above embodiment, the road to be traveled is informed by using both the display device 5 and the voice output device 12, but it may be informed by either one of them.

Various other design changes can be made within the scope of the claims.

[0044]

As described above, according to the intersection guide device of the present invention, when the exit link for the vehicle to travel is a route including a route code, the route code is notified. Therefore, even when there are a plurality of intersections in the immediate vicinity, the driver can easily determine which intersection the route guidance relates to by visually recognizing the guide sign with the route code. Further, since the route abbreviations mainly composed of numbers are used, it is possible to sufficiently store even a storage device having a small storage capacity as compared with the case of storing a destination name and the like.

Therefore, even when there are a plurality of intersections in the immediate vicinity of the intersection to be route-guided, it is possible to accurately guide the road to proceed without using a large-capacity storage device. Therefore, the driver can surely reach the destination.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a navigation device of an embodiment to which an intersection guidance device of the present invention is applied.

FIG. 2 is a diagram showing an example of a guide sign.

FIG. 3 is a schematic diagram showing an example of a link configuration.

FIG. 4 is a diagram for explaining an exit link and an entry link.

FIG. 5 is a diagram illustrating a method of determining an absolute azimuth of a link included in the link data in a polygonal line link.

FIG. 6 is a functional block diagram of a controller forming a part of the navigation device.

FIG. 7 is a flowchart showing route guidance processing in the controller.

FIG. 8 is a diagram showing an example of a display screen in normal route guidance.

FIG. 9 is a diagram showing an example of a display screen in route guidance using a route code.

FIG. 10 is a diagram illustrating a case where there are a plurality of intersections in the immediate vicinity for explaining a conventional defect.

[Explanation of symbols]

 4 Position detecting device 5 Display device 6 Controller 7 Road map memory 12 Voice output device

Claims (1)

[Claims] 1. A position detecting means for detecting a current position of a vehicle, a road map memory in which road map data is stored in advance, and a destination from the road map memory according to a setting of a destination by a driver. Road map data reading means for reading road map data of the range; route calculating means for calculating an optimum route to reach the destination based on the road map data read by the road map data reading means; Route storage means for storing the optimum route calculated by the route calculation means, link data regarding a link entering an intersection to be routed specified in advance, link data regarding a link leaving the intersection, and its exit If the link has a route code, the route code is stored in the link data in association with each other. The difference guidance data storage means, the judgment means for judging whether the vehicle has reached the link entering the intersection, or whether the vehicle has approached a predetermined distance from the intersection, and the judgment means. As a result, when it is determined that the vehicle has reached the link entering the intersection or is approaching a predetermined distance before the intersection, link data relating to the link entering the intersection stored in the intersection guidance data storage means is stored. A notification means for specifying a link for the vehicle to leave based on the link data relating to the link leaving the intersection and, if the specified link for leaving has a route abbreviation, notifying the route abbreviation An intersection guidance device comprising: