JPH1089985A - Navigation system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a navigation system for vehicle in which a user can search a course with no anxiety by determining a returning course corresponding to a currently traveling outgoing course and storing the returning course in the form of a returning course data thereby reducing the cost for retrieving the road data stored sequentially when traveling on the outgoing course. SOLUTION: Assuming a preset outgoing course passes through roads (1) 1a → (6) 6a → (9) → (13) → (16) in this order. Since the road (1) runs in the vertical direction, the 1b direction is stored as a returning course data in an RAM when a vehicle is traveling in the direction 1a on the road (1) in order to reduce the searching cost. When the vehicle is guided to a road (9) at an intersection II, a downward load (10) closest to the road (9) is stored as a returning course data in the RAM in order to reduce the searching cost because the road (9) is a vertical one way road on which a center line 51 exists. According to the arrangement, the vehicle can be guided on a returning course identical to the outgoing course as much as possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle navigation system.

[0002]

2. Description of the Related Art Conventionally, techniques in such a field include (1) a route guidance method in a vehicle navigation system, in which a registration start key is pressed at a departure place on an outbound route and then a registration end key is pressed at a destination. Until the passing, the passing nodes of the vehicle are detected and stored in the memory in order, and the passing nodes are used in reverse order as the guide route data of the return route. For example, if there are two nodes stored on the outbound route, such as when detouring, when creating the return route, delete the overlapping passing nodes and do not depart on the return route from the destination on the outward route. A route to the departure point is created (for example, see Japanese Patent Application Laid-Open No. 7-320194).

(2) In a route search display device that displays the current position of a car or the like on a display device together with a map, and particularly searches for an outbound route and a return route to a destination and displays them on the display device, the destination is set. When a route search request is made, an outgoing route from the departure point to the destination is searched for and displayed on a map. Thereafter, the destination and the departure place are exchanged, and a return route search is performed. When the display instruction is given for this return path, the display is performed (for example, see Japanese Patent Application Laid-Open No. Hei 7-134796).

[0004]

However, according to the system disclosed as the prior art (1),
A passing node of the vehicle on the outbound route is registered, and on the return route, a readout route is created in the reverse order of the registered passing nodes on the outbound route, but, for example, it is possible to pass on an outbound route such as a one-way road. On the return route, there are some roads that are not allowed to pass, and it may not be possible to provide accurate guidance on the return route simply by reading the outward route in reverse order.

Further, when the user arrives at the destination set first, completes registration of a passing node on the outward route, moves around the destination without setting a route, and returns to the first departure point,
If you do not return to the registered route on your outbound route by yourself, you will not be able to receive guidance. According to the system disclosed in the above (2), the destination on the outward route is set as the departure point on the return route, and the route on the return route is searched in advance with the departure location as the destination, and the result is stored. As a result, after reaching the destination, route guidance can be performed without performing a return route search operation.

However, the return route is determined in advance when the departure point and the destination are determined at the time of the forward route search. The return route is simply determined by reversing the departure point and the destination and searching for the optimum route. It is not a search for a return trip with the information taken into account. Therefore, when traveling out of the initial search route while traveling on the outbound route, re-searching automatically or from a point where the route deviation is recognized by the instruction of the user, and receiving guidance guidance on a new route, The new route is not considered at all on the return route.

[0007] For example, suppose that the user returns to the first place of departure after completing the destination for an unknown land. On the return route (return route) from the destination, traveling on the same road as the outward route is easier to travel because the driver has traveled once and understands the road condition to some extent. Here, in a navigation system in which a route search from a departure point or a current position of a vehicle to a destination is performed in advance and route guidance is performed by voice or display at an intersection or a junction according to the route, if the vehicle is running off the route, It is desirable to automatically re-search for a new route from the current position when the judgment is made.

When it is determined that the vehicle is running off the route, a key for starting the re-search is displayed, and when the key is input, the re-search is performed from the current position. Is preferred. Further, even while traveling on the route, by issuing an instruction to search for another route,
I want to partially bypass the original route or re-search for a completely different route.

[0009] Further, the user may deliberately deviate from the original route to search again, search for another route, or edit the route, depending on some circumstances or the preference of the user alone. For example, if the user knows the road, such as around the departure point, and there is always a congested main road on the route and wants to avoid that road, the route is edited by re-searching. This edited route is not the optimal route at the time of the initial search, but is a route that the user prefers, and there is a demand that the user wants to follow the route on the return route as much as possible.

According to the above-mentioned prior arts (1) and (2), such a demand from the user is not satisfied. The present invention solves the above problems, reduces the cost of searching for sequentially stored road data on an outbound trip, uses the road data as a resource on a return trip, and allows a user to search for a route that is safe for the user. It is an object to provide a navigation device.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides: (1) a vehicular navigation system which recognizes a currently traveling road while traveling on an outbound route from a departure place to a destination. Therefore, the road of the return trip corresponding to the road of the outward trip is acquired and stored as the return trip data, and when there is a request for the return trip guidance,
The search for the return route is performed by lowering the cost of the obtained return route data.

(2) In the vehicle navigation apparatus, when traveling on the outward route from the departure point to the destination, the currently traveling road is recognized, and the recognized road data of the outward route includes data in the vertical direction. In the case where the data on the opposite direction to the direction currently in progress is obtained, and the recognized road data on the outbound route does not have the data in the vertical direction, the road data within the predetermined range from the recognized road data on the outbound route is obtained. Is retrieved and stored as return route data, and when a request for return route guidance is made, the cost of the obtained return route data is reduced to search for a return route.

(3) In the vehicular navigation apparatus according to the above (2), the predetermined range is within a predetermined distance from a road data of a recognized outward travel that is currently running and is within a predetermined angle difference. It is a road. (4) In the vehicle navigation device, information storage means storing road data, input means for setting a destination and a departure place, current position detection means for detecting the current position of the vehicle, and data relating to the route are temporarily stored. A departure point input by the input means or a vehicle current position detected by the current position detection means as a departure point, and a route from the departure point to a destination input by the input means. Route calculation means for performing a route search using the road data stored in the information storage means; and a route guidance based on the route searched by the route calculation means and the vehicle current position detected by the current position detection means. Control means for storing the data of the return path in the storage means with the currently traveling path as the outward path, and the control means,
Based on the current position of the vehicle detected by the current position detection means and the road data stored by the information storage means, the currently traveling road is recognized as a forward road, and a return road corresponding to the forward road data is recognized. When data is obtained and stored in the storage means as return data, when the previous departure point is input as the destination by the input means,
The route calculation means reads out the road data of the return route stored in the storage means, and performs a route search by lowering the search cost of the road data.

(5) In the vehicular navigation apparatus according to the above (4), when the control means acquires the return road data corresponding to the forward road data, the forward road data has vertical data. In this case, data in the direction opposite to the direction currently in progress is obtained, and when the recognized road data on the outbound route does not have data in the up-down direction, a road within a predetermined range from the recognized road data on the outbound route is obtained. Data is retrieved and obtained and stored in the storage means as return data.

(6) In the vehicular navigation device according to the above (5), the predetermined range is within a predetermined range from the recognized road data of the outbound route that is currently traveling and within a predetermined angle difference. It is a road.

[0016]

According to the present invention, according to the present invention, when traveling back and forth between the starting point and the destination,
Guidance can be provided on the same route as the outward route (opposite road) as much as possible, especially when the user performs route editing such as re-searching for the optimal route in the initial search on the outward route and runs on the user's favorite route In addition, the favorite route is also reflected on the return route. In addition, even when a return route is searched from a point distant from the destination on the outward route, the search can be performed so as to pass through the outward route as much as possible. Also,
Since the road data of the return route corresponding to the route information of the outward route is stored in advance, the resources can be used, the search cost on the return route is reduced, and the search time is short.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of a vehicle navigation device showing an embodiment of the present invention. As shown in FIG. 1, a vehicle navigation device according to the present invention includes an input / output device 1 for inputting and outputting information related to route guidance,
A current position detection device 2 for detecting or receiving information on the current position of the vehicle, navigation data necessary for route calculation, display / voice guidance data and programs (OS and / or application) required for route guidance, etc. And a central processing unit 4 that performs display / voice guidance processing necessary for route search processing and route guidance and controls the entire system. First, each configuration will be described.

The input / output device 1 performs a navigation process according to the user's intention so that the user can input a destination or output guidance information from at least one of a voice and / or a screen when necessary. It has a function of instructing the central processing unit 4 and printing out the processed data and the like. As means for realizing the function, the input unit includes a touch switch 11 and an operation switch for inputting a destination as a telephone number or coordinates on a map, and for requesting route guidance. Of course, an input device such as a remote controller may be used.

The output unit includes a display 12 for displaying input data on a screen and automatically displaying route guidance on a screen in response to a user's request, and a data and information storage device processed by the central processing unit 4. The printer 13 includes a printer 13 that prints out data stored in the printer 3 and a speaker 14 that outputs route guidance by voice. Here, a voice recognition device for enabling voice input and a recording card reader for reading data recorded on an IC card or a magnetic card can be added. Further, a data communication device for exchanging data with an information source such as a personal computer in which user-specific data such as map data and destination data are stored in advance can be added.

The display 12 is composed of a color CRT or a color liquid crystal display, and is necessary for navigation such as a route setting screen, a section map screen, an intersection map screen based on map data and guidance data processed by the central processing unit 4. In addition to outputting all screens in color display, buttons for setting route guidance, performing guidance during route guidance, and performing a screen switching operation are displayed on this screen. In particular, the passing intersection information such as the passing intersection name is displayed in color in a pop-up on the section map screen at any time.

The display 12 is provided in the instrument panel near the driver's seat, and the user confirms the current location of the vehicle by looking at the displayed map.
In addition, it is possible to obtain information on a route from now on. Further, the display 12 is provided with a touch switch (input device) 11 corresponding to the display of the function button, and is configured such that the above operation is executed based on a signal input by touching the button. Have been.
The input signal generating means including the button and the touch switch constitutes an input unit, but a detailed description thereof is omitted here.

The current position detecting device 2 is a device for detecting or receiving information relating to the current position of the vehicle, and an absolute direction sensor 24 composed of a geomagnetic sensor and the like. A relative direction sensor 2 composed of a steering sensor, a gyro, and the like.
5. Distance sensor 2 for detecting running distance from the number of rotations of wheels
6. Consisting of a GPS receiving device 21 using a satellite navigation system (GPS) and a VICS receiving device 22 or a data transmitting / receiving device 23 as traffic information acquiring means, the VICS receiving device 22 multiplexes road traffic information by FM. The data transmission / reception device 23 is, for example, a mobile phone or a personal computer, and exchanges information necessary for navigation with a traffic information center (for example, ATIS) at the request of the user. Is what you do.

The information storage device 3 is an external storage device in which a navigation program and data are stored in an external storage medium such as a CD-ROM (hereinafter, simply referred to as a CD), an optical CD, an IC card, or the like. The navigation program includes a map drawing unit, a route search unit, a route guidance unit, a current position calculation unit,
It is composed of a destination setting operation control section, etc., and is composed of an application section that performs signal processing for navigation, an OS section, and the like. Here, a program for performing processing such as route search, display output control necessary for route guidance, and voice are provided. A program for performing voice output control necessary for guidance and data necessary for the program, and display information data necessary for route guidance and map display are stored. Data includes map data, intersection data, road data, various guidance data, etc.
All data necessary for navigation are stored.

More specifically, a program for setting a destination and a passing point based on position information from the current position detecting device 2 and an input signal from the input device 11 and executing a route search using searched road data, A program that converts the searched road data and executes the route search again when it deviates from, or a program for determining map drawing, map matching, audio output timing along the route and the content of the voice phrase, and A program that converts a traveling road into return data and stores the data, and when the departure point was previously selected as the destination, reads out the stored return data and changes the search cost to execute a route search. Are stored, and by driving the programs stored in the information storage device 3, each function of the navigation in the present invention is executed. That. That is, in the present embodiment, a program for realizing the functions of the present invention is stored in the information storage device 3 which is an external storage medium.

The central processing unit 4 includes a CPU 40 for executing various arithmetic processing, and a flash memory 41 for reading and storing a program from a CD of the information storage device 3. The flash memory 41 is for erasing an existing program at a time even if there is a change in the CD program. Also, the flash memory 41
A first ROM 43a storing a program (program reading means) for performing a program check and update process of
The set point coordinates of the destination and the road code No. And the like, and a RAM 42 for temporarily storing searched route guidance information and data being processed, and a second ROM 43b for storing display information data necessary for route guidance and map display. Note that a program for performing the above-described update processing may be stored in an external storage device.

The program according to the present invention and other programs for executing navigation may be all stored in a CD-ROM as an external storage medium, or a part or all of the programs may be stored in a ROM ( Second
It may be stored in the ROM 43b). Various navigation functions are realized by inputting data and programs stored in the external storage medium as external signals to the central processing unit of the navigation apparatus main body and performing arithmetic processing.

Further, an image memory 44 in which image data to be used for displaying a screen on the display 12 is stored.
The image data is extracted from the image memory based on the display control signal from U40, subjected to image processing, and
The image processor 45 outputs the voice, phrase, one sentence, sound, and the like read from the RAM 42 based on the voice output control signal from the CPU 40 to output the analog signal to the speaker 14. A voice processor 46, a communication interface 47 for exchanging input / output data with a communication device, a sensor input interface 48 for capturing a sensor signal of the current position detection device 2, and a clock 49 for writing date and time in internal diagnostic information. Etc. are provided.

In the central processing unit 4, when data acquired by each sensor of the current position detecting device 2 is fetched from the sensor input interface 48, the CPU 40 calculates the current position coordinates at regular time intervals based on the data. The data is temporarily written to the RAM 42. The current position coordinates are obtained by performing a map matching process in consideration of detection errors of various data. The output values of the various sensors are constantly corrected. Here, route guidance is performed by screen display and voice output, and the user is able to select the presence or absence of voice output.

FIG. 2 shows a guide road data file in which data necessary for calculating a route and performing route guidance by the route calculating means is stored. For each of the number n of roads, a road number, a length, It consists of road attribute data, shape data address, size, and guidance data address and size data. The road number is set for each of the outgoing and returning routes for each road between the branch points. The road attribute data is data indicating whether the road is an elevated road, next to an elevated road, an underpass, an underpass, or the number of lanes. When each road is divided into a plurality of nodes (nodes), the shape data has coordinate data including east longitude and north latitude for each of the number m of nodes.

The guidance data includes the names of intersections (or junctions), the presence / absence of traffic lights, the presence / absence of pedestrian crossings, the characteristics of junctions and landmarks (traffic signs, signs at gas stations and convenience stores, etc.), , Tunnel entrance, exit, width reduction point, etc.), road name [information of road type of expressway, general road (national road, prefectural road, etc.)], address of road name voice, size and destination data It consists of address and size data. The destination data includes a destination road number, a destination name, an address of destination name voice data, a size and a destination direction data, and travel guide data (information from right to left or from the center). The destination direction data is invalid (do not use destination direction data), unnecessary (do not guide), go straight,
This is data indicating information on a diagonally right direction, a right returning direction, a left direction, a diagonally left direction, and a left returning direction.

Although the data structure of FIG. 2 stores road data and information on intersections, as shown in FIG. 3, intersection data is provided separately from road data.
The presence or absence of a traffic light, information on a road to be connected, and the like may be stored. However, if the road information is provided with the connection information, the data such as the impossibility of entry from a certain road to a certain road can be easily provided and the data amount can be reduced.

FIG. 4 is a flowchart showing the flow of the processing of the entire vehicle navigation system of the present invention. (1) First, a current position (departure point) required for a route search is acquired by the current position means (step S1). (2) Next, on the destination and passing point setting screen, the setting conditions of the destination and the passing point are input via the input device to set the destination and the passing point (step S2).

(3) Next, a route search from the current position to the destination / passing point is performed by the route searching means (step S3). (4) Next, when the guidance start key of the input device is pressed on the searched route to start the route guidance, the position of the own vehicle is measured by the current position detecting means, and the current position is tracked. Route guidance at an intersection or a junction where a left turn is to be made is displayed or voiced (step S4).

Next, a vehicle navigation system according to an embodiment of the present invention will be described. FIG. 5 is a flowchart of vehicle navigation showing an embodiment of the present invention. (1) First, a destination is set (step S11). (2) Next, it is checked whether or not the destination set in step S11 is the previous departure point (step S1).
2).

(3) Next, in the case of the previous departure point,
For example, it is checked whether or not there is a change in the search conditions, such as switching whether to give priority to a toll road or switching the preference of a route search (step S13). (4) Next, if there is no change in the search condition, the search cost is changed based on the return data (step S14). Details of this processing will be described later.

(5) Next, a passing point is set (step S15). (6) Next, it is checked whether a departure place is set (step S16). (7) Then, if YES in step S16, a departure place is set (step S17). This departure point is a point different from the current position of the vehicle, and the user knows the road around the current position well and does not need route guidance.For example, when selecting the nearest interchange as the route guidance start point Used for

(8) If NO in step S16, the current position is set as the departure point (step S18). (9) Next, a route search is performed from the departure point set in step S17 or the current vehicle position set in step S18 to the destination set in step S11 (step S19). Here, when a passing point is set, a route passing through the passing point is searched.

(10) The current position is tracked (step S20). (11) Next, route guidance is performed based on the current vehicle position (step S21). (12) Next, a return data acquisition process is performed (step S).
22). (13) Next, steps 20 to 2 are performed until the destination is reached.
Step 2 is repeated (Step S23). Here, step S
If it is determined in step 20 that the acquired current position of the vehicle is out of the route, the route is searched again automatically or manually by the user, but the details are omitted.

Next, a flow chart (subroutine) of the return data acquisition processing (step 22) of FIG. 5 will be described with reference to FIG. (1) First, the current position is detected (step S31). (2) Next, the currently traveling road and the traveling direction are recognized (step S32). This process is performed by a well-known map matching process.

(3) Next, it is checked whether or not the currently acquired road data has vertical data (step S33). For example, in FIG.
There is no road, and data in the vertical direction is stored in one piece of road data [1a direction and 1b direction in the road data of (1)]. (4) Next, in the case of NO in step S33, since data in the opposite direction is not stored in the currently acquired road data, a road within a predetermined distance range and within a predetermined angle difference is searched. (Step S34).

(5) Next, as a result of the search processing in step S34, it is checked whether there is a corresponding road (step S35). (6) Next, if there is a corresponding road, the search cost of the searched road is reduced and acquired as return data (step S36). (7) If YES in step S33, data in the opposite direction of the acquired road is acquired,
Proceed to step S38 (step S37).

Also, in the case of NO in step S35, the process proceeds to step S38. (8) It is checked whether or not the acquired road data has already been registered (step S38). (9) Next, if it is not registered in step S38, the acquired road data is stored in the RAM 42 as return data (step S39).

(10) Next, it is checked whether a predetermined time has elapsed (step S40). For example, the return data processing in FIG. 6 will be described with reference to FIG. 7, which simply shows a road data structure (a link state of road data). Here, (1), (2),... In FIG. 6 are the road numbers of the road data stored in the information storage device 3, and I, II,. For example, (1), (6), (11)
Is a road without the median strip 51, and data in the vertical direction is stored in one road data [the road data of (1) direction 1a and 1b]. Also, for example, road numbers (9), (10), (13), and (14) are roads that cannot move from the same lane to the lane where the median strip 51 is located, and are in the opposite direction (9). (10) is stored as another one-way road data.

Here, the preset route (outbound route) is
(1) (1a) → (6) (6a) → (9) → (13) → (16). (A) Since the road (1) is a vertical road, the search cost is reduced and stored in the RAM 42 while the road 1a is traveling in the 1a direction as the 1b direction as return data.

(B) Next, when the route of the road (6) is guided at the intersection I (passing point), the road (6) is also a vertical traffic road. During the progress, the direction 6b is stored in the RAM 42 as return data, with the search cost reduced. (C) Next, at the intersection II (passing point), when the road (9) is guided, the road (9) has the median strip 51 and is a one-way road in the upper and lower directions. Road (9)
The road (10), which is the downward road closest to, is stored in the RAM 42 as return data at a reduced search cost.

(D) Next, when the route of the road (13) is guided at the intersection III (passing point), the road (13) also has the median strip 51, and the road (13) is an upper and lower one-way road. Therefore, the road (14), which is the downward road closest to the road (13), is stored in the RAM 42 as return data at a reduced search cost. (E) Next, at the intersection V (passing point), when the road (16) is guided, the road (16) is also a one-way road, so that the road (16) has the closest angle to the road (16). The road (17), which is the direction road, is stored in the RAM 42 as return data at a reduced search cost.

As described above, on the outward route, the return route data closest to the outward route is stored with the search data lowered, so that the return route data is obtained between the passing points, that is, for each node. As shown in FIG. 8, the route data string in FIG.
a−6a− (9) − (13) − (15)..., and on the outbound route, the road data (17) − (14) − (10) −6b−1b is reduced in search cost to return data. Can be obtained as

As one-way roads other than the above,
There are highways and toll roads separated vertically. Next, another embodiment of the present invention will be described. FIG. 9 is a navigation flowchart showing another embodiment of the present invention. (1) First, a destination is set (step S51).

(2) Next, a passing point is set (step S52). (3) Next, it is checked whether to set a departure place (step S53). (4) Next, in the case of YES in step S53, a departure place is set (step S54). (5) If NO in step S53, the current position is set as the departure point (step S55).

(6) Next, a route search is performed (step S)
56). (7) The current position is tracked (step S57). (8) Next, route guidance is performed (step S58). (9) Next, the above-mentioned return route data is obtained for each node. (Step S59).

(10) Next, it is checked whether or not the storage mode (A) of the return path data for each node is turned off (step S60). That is, for example, when the user selects a route that the user does not want to select as a return route, that is, when the user wants to take a detour, the user operates the input / output device 41 to
The storage mode (A) of the return data for each node is turned off.

(11) Next, the storage mode (A) of the return path data for each node is turned off, and the process proceeds by a normal route search (search in which the return path data is not stored) (step S61). If NO in step S60, the process proceeds to step S64. (12) Next, when it is desired to enter the outward route where the return data is to be obtained from the detour, storage of the return data for each node (A)
Check whether to return to the mode (step S6)
2).

(13) Next, in step S62, Y
In the case of ES, return data is acquired again for each node (step S63). (14) Next, head to the destination, until you reach the destination,
The above steps are repeated (step S64). (15) Next, while using the traveling history information described above for the return route search, a re-search for the detour section is performed (step S).
65).

(16) Next, the data is converted and stored in the return path (step S66). FIG. 10 is a diagram showing a route data string according to another embodiment of the present invention. As shown in this diagram, for example, as the outbound route data, road A is 101, road B is 108, and road C is 11
0, 115 for road D, 121 for road E, 12 for road F
6. When the travel history of the road G is stored as 130,.
When traveling on this outbound route, road A is 1
02, Road B is 109, Road C is OFF (sidewalk), Road D is OFF (sidewalk), Road E (return to main line) is 12
7, the road F is stored with the search cost reduced to 133,..., So that return data can be obtained.
In the above-described embodiment, the portion that does not need to be left as return data by the user while traveling on the outbound route is set to OFF so as not to be left. However, the return data may be partially deleted after the end of route guidance on the outward route. .

At the time of route search, an optimum route is obtained based on link information and cost information. There are various searching methods. (A method of combining road rows in a tree structure from the destination and selecting the one with the lowest cost as the optimal route, a method of sequentially selecting and connecting the ones with the lowest cost among multiple intersections connected in order from the destination, data Is divided into blocks, a method of narrowing down the search target block in advance, having data in a coarse and dense hierarchical structure,
There is a method of searching by moving up the hierarchy in order from both sides of the destination).

For example, as a method of searching for a road in step S34 in FIG. 6, a predetermined area is set from the coordinates of the starting point and the ending point of the road which is currently obtained during traveling on the outbound path, and the current data is obtained for the road data entering the area. Calculate the angle difference between the road and the road. However, if the road being compared is a one-way road, the direction is also considered. As a method of setting a predetermined area from the currently acquired road,
There are methods of setting a rectangular area around the coordinates of the start point and end point of road data, or setting a circle of a predetermined radius as an area. In addition, there is a method of setting a rectangular area or a circle having a predetermined radius around the coordinates of the current position of the vehicle.

As for a method of searching for a road having an angle difference from the currently acquired road, the angle of the currently traveling road (may be stored in advance in the road data. Is stored as the start point and the end point, the start point and the end point are divided and stored according to the node coordinates based on the road shape, and the node coordinates of the vehicle current position are determined. The inclination between two points may be set as the angle.) And the angle difference between the two points is 180 ° ± a.

In the embodiment shown in FIGS. 5 and 6,
Although the return route data is sequentially stored during the forward route, the route data traveled on the forward route may be extracted after completion of the forward route guidance, and the process of converting the route data into the return route data may be performed. . When converting the searched route into the return route data, when it is determined that the vehicle has traveled without deviating from the initial search route, the return route data may be obtained from the route. The same applies to a case where another route is searched for on the initial search route and the vehicle travels along the route.

When the vehicle has deviated from the initial search route and is in the automatic re-search mode, the route to the route departure point and the re-search route may be connected and registered as an outbound route. In addition, in the case of the manual re-search mode in which the user performs a re-search at a time desired by the user, when the vehicle deviates from the route and travels without performing the re-search for a while, the route to the route departure point is re-established. What is necessary is just to connect to the point where the search was executed and register it as an outbound route.

In addition, in a system that receives traffic information by VICS for route driving and performs a re-search based on traffic congestion and congestion information, a portion where a route is changed by traffic information is stored (for example, an initial search route). If traffic congestion is detected ahead of the current position while traveling on the road and a re-search is performed to avoid that part, the original route is registered as an outbound route. This is because the traffic congestion may be resolved when you return home after completing your business.

Further, in the above embodiment, in step S12 of FIG. 5, it is determined whether or not the input destination is the last departure point. A key such as “departure point” may be displayed so that the coordinates of the departure point in the previous route guidance can be selected as the destination. Alternatively, the coordinates of the previous departure point may be registered, and when the periphery of the coordinates is input as the destination, it may be determined that the previous departure point has been input. Specifically, it is assumed that a rectangular area or a predetermined area of a predetermined radius circle is set centering on the previous departure point, and when the input destination is within the area, the previous departure point is set as the destination. .

Regarding the process of changing the search cost based on the return route data in step S14 of FIG. 5, the road data previously stores, for example, a road length, a road width, and a road attribute as data for performing the cost calculation during the route search. However, in the return data change processing, the cost may be reduced by multiplying or subtracting a predetermined value from a road cost based on data stored in advance.

In the above-described embodiment, the cost of the return data acquired during the forward travel is reduced and the return search is performed when the return guidance is requested. However, the return data acquired during the forward travel is used. Is connected in advance,
If it is used at the time of a return route guidance request, the return route search processing becomes faster. At this time, in a case where the vehicle travels on a one-way road during the forward traveling, for example, even if the process of step S34 in FIG. Just search for it.

Further, the present invention is not limited to the above-described embodiment, and various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a vehicle navigation device showing an embodiment of the present invention.

FIG. 2 is a diagram showing a structure of road data of the vehicle navigation device according to the present invention.

FIG. 3 is a diagram showing intersection data of the vehicle navigation device according to the present invention.

FIG. 4 is a flowchart showing the flow of processing of the entire vehicle navigation system of the present invention.

FIG. 5 is a flowchart of vehicle navigation showing an embodiment of the present invention.

FIG. 6 is a flowchart illustrating a return data acquisition process according to an embodiment of the present invention.

FIG. 7 is a diagram showing a specific route example showing an embodiment of the present invention.

FIG. 8 is a diagram showing a route data string showing an embodiment of the present invention.

FIG. 9 is a navigation flowchart showing another embodiment of the present invention.

FIG. 10 is a diagram showing a route data string showing another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 input / output device 2 current position detecting device 3 information storage device 4 central processing unit 11 touch switch 12 display 13 printer 14 speaker 21 GPS receiving device 22 VICS receiving device 23 data transmitting / receiving device 24 absolute direction sensor 25 relative direction sensor 26 distance sensor 40 CPU 41 Flash memory 42 RAM 43a First ROM 43b Second ROM 44 Image memory 45 Image processor 46 Audio processor 47 Communication interface 48 Sensor input interface 49 Clock 51 Central divider

Claims (6)

[Claims] 1. While traveling on an outbound route from a departure point to a destination,
Recognizing the currently traveling road, acquiring the return road corresponding to the outward road and storing it as return data, and when a request for return guidance is issued, the cost of the acquired return data is reduced. A navigation device for a vehicle, wherein the navigation device is lowered to search for a return route. 2. While traveling on the outward route from the departure point to the destination,
Recognizing the road on which the vehicle is currently traveling, if the recognized road data of the outward route has data in the up-down direction, obtains data in the direction opposite to the direction in which the vehicle is currently traveling. If there is no data in the up-down direction, the road data within a predetermined range is searched and obtained from the recognized road data of the outbound path and stored as return-path data. A vehicular navigation device for performing a search for a return route by lowering the cost of the acquired return route data. 3. The vehicle navigation device according to claim 2, wherein the predetermined range is a road that is within a predetermined distance from a road data of a recognized outward road that is currently running and within a predetermined angle difference. A navigation device for a vehicle, comprising: 4. An information storage means for storing road data, an input means for setting a destination and a departure place, a current position detection means for detecting a current position of a vehicle, and a storage for temporarily storing data relating to a route. A departure point input by the input means or a vehicle current position detected by the current position detection means, and a route from the departure point to a destination input by the input means is used as the information storage means. Route calculating means for performing a route search using the road data stored in the vehicle, and performing route guidance based on the route searched by the route calculating means and the current vehicle position detected by the current position detecting means. Control means for storing data of the return path in the storage means with the route of the vehicle as the outward path, wherein the control means detects the current position of the vehicle detected by the current position detection means. The road on which the vehicle is currently traveling is recognized based on the road data stored by the information storage means, and the road on the outbound path is recognized. The road data on the return path corresponding to the road data on the outward path is obtained, and the storage means is used as the return data. When the previous departure point is input as the destination by the input means, the route calculation means reads the return road data stored in the storage means and reduces the search cost of the road data. A navigation device for a vehicle, wherein a route search is performed. 5. The vehicular navigation apparatus according to claim 4, wherein the control means, when acquiring the return road data corresponding to the outward road data, when the outward road data has vertical data. Acquires data in the direction opposite to the direction currently in progress, and if the recognized road data of the outward route does not have data in the vertical direction, the road data within a predetermined range from the recognized road data of the outward route is obtained. A navigation device for a vehicle, characterized in that it is retrieved and obtained and stored as return data in the storage means. 6. The vehicle navigation device according to claim 5, wherein the predetermined range is a road that is within a predetermined range from the recognized road data of the outbound road that is currently traveling and that is within a predetermined angle difference. A navigation device for a vehicle, comprising: