JP2973967B2 - Route search processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route search processing method, and more particularly to a dynamic route guidance (DRGS) for re-searching a moving route according to a change in traffic information obtained from outside.

[0002]

2. Description of the Related Art Conventionally, VICS (Vehicle Informa)
(Traffic Communication System) to obtain traffic information such as link travel time from the information center, and to reach the destination in the shortest time based on this traffic information (recommended)
A dynamic route guidance system (DRGS) that searches for a moving route and provides the route to a driver has been proposed. In such a system, the driver recognizes a moving route and various information provided by the system by a display or voice guidance, and performs a driving operation in accordance with the route guidance information, thereby providing a more comfortable and less fatigued driving. It can be performed.

[0003] By the way, since the information provided to such a system changes every moment, even if a travel route to a destination is searched based on information at a certain time, a new route during the travel along the travel route may be searched. The acquisition of information (for example, accident information or the like) may make the current travel route invalid.
For this reason, some of the above systems have a function of automatically re-searching for a new moving route when acquiring new information affecting the moving route. In order to effectively use the new travel route by this re-search, it is necessary to end the re-search before passing through the branch point based on the old travel route, and to present it to the driver.

[0004] In view of such a situation, the present applicant disclosed in Japanese Patent Application Laid-Open No. Hei 7-83685 a predetermined distance before a branch point in consideration of a route selection time and a re-search processing time by a driver. We proposed a technique to set a search start flag and automatically start a re-search. According to this technique, the search for the new route can be surely terminated before the branch point, so that the old moving route that has become meaningless immediately before or after the branch point is not presented to the driver.

Generally, in such a system,
When providing the searched travel route to the driver, route guidance related to the branch is performed by voice guidance at a predetermined distance before a branch point (for example, an intersection or an interchange).
The content of the voice guidance is, for example, "Turn left 300m ahead. ]. By the route guidance based on the voice guidance, the driver can perform the driving operation with a margin without being confused by the information on the moving route supplied from the system.

[0006]

However, since information such as traffic information provided to the system changes every moment as described above, the best travel route is determined each time the system obtains new information. Will change. In the above-mentioned technology, once the travel route is searched and confirmed, "300 m ahead, left turn" is followed according to the travel route. Is output as a voice, but if new information such as traffic congestion is received during the output of the route guidance, if the system determines that re-search processing can be performed, the route guidance process (output) is interrupted. To stop and start the re-search processing of the moving route. In other words, there is a case where the voice guidance as the route guidance is outputted, for example, as "300 m" when trying to provide the latest route guidance. This halfway and meaningless voice output is bothersome for the driver and causes a problem of confusion for the driver.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a route search that can perform a re-search for a moving route at an appropriate timing without giving a driver trouble or confusion. It is an object to provide a processing method.

[0008]

In order to achieve the above-mentioned object, a configuration of the present invention searches for a moving route to a destination based on acquired information and determines a branch point of the moving route. In a route search processing method used in a route guidance device that provides route guidance before a distance, a re-search process of a moving route performed by a change in information after the route search is prohibited at least after the start of the route guidance. I do.

Here, the start timing of the route guidance is a timing at which the driver can perform the driving operation of the vehicle with a margin according to the route guidance, for example, 300 m before a junction such as an intersection on an ordinary road, an interchange. It is 1 km before the fork on a toll road having a road and a service area, and 2 km on the expressway. According to this configuration, even if information that affects the previously searched movement route is obtained, if the route guidance has already been started, the route guidance is maintained valid, and the re-search of the movement route is prohibited. You. That is, the re-search processing of the new moving route is performed on the route after the output route guidance. Therefore, the output route guidance is not interrupted, and the driver is not bothered or confused.

[0010] In order to achieve the above object, in the configuration of the present invention, the re-search is prohibited from a point in time when the time required for the re-search processing is further advanced from the start of the route guidance.

[0011] According to this configuration, the re-search is performed only when the route guidance can be performed at a timing when the driver can perform the driving operation with a margin, so that the halfway route guidance is not performed and the driving is not performed. The trouble and confusion are not given to the person.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a route guidance apparatus to which the route search processing method according to this embodiment can be applied. The transceiver 10 obtains information necessary for a route search such as traffic information by communicating with an optical beacon or a radio beacon provided on the roadside. Specifically, detailed traffic information of a forward 10 km radius is acquired from an optical beacon, and traffic information of an expressway or a road belonging thereto is acquired from a radio beacon. The traffic information includes a degree of congestion of each link (a reference unit obtained by dividing a road according to a predetermined rule, for example, a unit divided at each intersection), travel time (required travel time) for each link, and regulations such as construction. The information is information, and the degree of congestion is represented by a plurality of evaluation levels (for example, congestion, congestion, and idleness).

The obtained traffic information is supplied to a VICS ECU (electronic control unit) 12. Also, EC for VICS
The U12 is provided with an FM antenna 14 and a receiver 16, and receives traffic information transmitted by FM multiplex broadcasting. This traffic information is wide area information in the FM reception area, and the obtained traffic information is supplied to the VICS ECU 12 in the same manner as the information obtained by the optical beacon or the radio beacon. V
The ICS ECU 12 transmits the traffic information (congestion degree, link travel time, regulation information, etc.) to the navigation ECU.
(Hereinafter simply referred to as a navigation ECU) 18. The navigation ECU 18 has a map database that stores map data including a map display link and a route search link, and a microcomputer that performs various calculations related to route search processing (including re-search) and controls each unit.
The route search link stored in the map database is read, and a travel route that can reach the destination in the shortest time is searched for in consideration of the traffic information supplied from the VICS ECU 12. At this time, for a link for which no traffic information is obtained among the route search links, a calculation for estimating the traffic information of a link having no information is performed based on the link from which the traffic information is obtained. The travel route obtained by the search is displayed on the display 20 as a (recommended) travel route to the destination. Further, the navigation ECU 18 is connected to a voice output device (speaker) 22 for outputting route guidance and accompanying information by voice, an input device (not shown) for receiving input information from a driver, and the like.

A feature of the present embodiment is that the VICS ECU 12 obtains new traffic information affecting the previously searched moving route at least after the latest route guidance from the voice output device 22 is started. In this case, re-search for a new moving route is prohibited. In other words, the route guidance during voice output is maintained valid, and the process of re-searching for a new moving route is performed from the point where the guidance ends. Roads that cannot be closed at all, such as closed roads and highway ramp closing information, can be recognized in advance based on information from various information centers. Therefore, road guidance for route guidance that is being output due to closed roads is not interrupted. .

FIG. 2 is a flow chart for monitoring the necessity of the re-search process performed in the microcomputer in the navigation ECU 18.

The navigation ECU 18 is a VICS ECU 12.
If a valid route is calculated based on the current information and a valid travel route is calculated based on the traffic information from, whether or not the information used to search for the travel route has changed with respect to the route before passing (whether there is new information) Monitoring is started (S100). The VIC
Since the information provided to the S ECU 12 changes every moment, information on the searched travel route is extracted from the information and monitored. This monitoring is performed in addition to the information on the moving route, as well as information when the traffic route is affected by traffic congestion or the like occurring on a road not directly related to the movement. If a change is found in the information provided to the VICS ECU 12 (information affecting the currently valid travel route), the navigation ECU 18 sets the re-search switch for forcibly executing the re-search to the driver. It is determined whether or not the operation has been performed (S101). This takes into account the driver's own judgment based on the surrounding conditions and the like.

If the re-search switch is not turned on in (S101), subsequently, route guidance based on the currently valid travel route is started, and it is determined whether or not the own vehicle has not passed the guidance junction. Is performed (S102). Here, the route guidance is performed for the nearest branch point (for example, an intersection or an interchange) on the moving route. The timing at which the route guidance is started is a point at which the driver can sufficiently recognize the guidance route so that the driver can perform a smooth driving operation at the junction, and is located on the moving route including the target junction. This is a position before a predetermined distance. This predetermined distance can be set arbitrarily. In the case of a general road, for example, 300 m,
For example, a toll road is 1 km, and a highway is 2 km, for example.
It is. When the route guidance is started, the display 18 is switched to an enlarged map including the position of the own vehicle and the branch point, and at the same time, the route guidance for instructing the driving operation from the voice output device 22, for example, "300 m ahead, left turn. Is announced.

When the navigation ECU 18 starts to provide route guidance for a target branch point, re-searching for a new traveling route is prohibited even if new information affecting the traveling route is input to the navigation ECU 18 (S103). ). Therefore, it is determined that the route guidance to the target branch point is valid. As a result, the route guidance device outputs a completed voice that is not interrupted on the way. Subsequently, the navigation ECU 18 monitors whether or not the vehicle passes the guidance junction, that is, returns to S102, and repeats the determination of whether route guidance has been started and whether or not the vehicle has passed the guidance junction. That is, the re-search process is stopped at least until the guidance branch point is passed. Therefore, if the route guidance for the next branching point is started immediately after the vehicle has passed the guidance branching point, the re-search for the new branching target is prohibited.

If it is confirmed in S102 that the route guidance has been started and that the vehicle has passed the guidance junction, the navigation ECU 18
Performs a re-search based on the provided new information (S10
4), a series of re-search processing ends. In other words, the route guidance is executed with the old travel route discarded and the re-searched new travel route enabled. Then, the navigation ECU 18 monitors the necessity of the re-search for the newly valid travel route (S
100 to S104).

In the above-described embodiment, when performing a re-search, a predetermined calculation time is required. In order to perform route guidance at a timing at which a driver can perform a smooth driving operation at a branch point, all re-search processing must be completed at the start timing of the route guidance (for example, 300 m before the branch point). For example, assuming that the calculation time required for the re-search based on the processing capability of the microcomputer in the navigation ECU 18 is about 20 seconds (depending on the complexity of the target route), the final automatic re-search start timing as shown in FIG. Becomes a position 20 seconds before the start of route guidance, and if the own vehicle passes through the search start position and performs a re-search, the route guidance may not be able to be started at an optimal timing.

In this case, the navigation ECU 18 may include the re-search processing time in the re-search prohibition condition. That is, as shown in FIG. 4, following the determination of whether or not the route guidance in S102 in the flowchart shown in FIG. 2 has started, the information from the acquisition point of the information affecting the currently effective travel route to the route guidance start point is obtained. The travel time T is calculated (S200). As described above, the route guidance start point is a predetermined distance (for example, L ₁ = 300 m for a general road, L ₂ = 1 km for a toll road,
In the case of a highway, for example, L ₃ = 2 km)
The information obtaining point can be easily recognized by referring to the map data of the navigation ECU 18. Accordingly, the navigation ECU18 can calculate the distance L _x to route guidance starting point of availability point information. Here, the legal traveling speed of a general road is V ₁ , the legal traveling speed of a toll road is V ₂ , the legal traveling speed of an expressway is V ₃ , the traveling speed in the past n minutes is V ₄ , and the computation speed used in the computation is and V _x. At this time, when V ₁ ≧ V ₄ , the calculation speed V _x is V _x = V ₁ , and when V ₁ <V ₄ , V _x = V ₄ . Also, V ₂ or V ₃ ≧
For V _4, the operation speed V _x as _{V x = V 2 orV 3,} V 2
When or V ₃ <V ₄ and V _x = V ₄ , the moving time T = L _x
/ Can be represented by V _x. In addition, the re-search required time t
Is a preset value (20 seconds in this embodiment).

Then, the navigation ECU 18 compares the required re-search time t with the travel time T (S201). And
If t> T, that is, if the travel time T until the start of route guidance is shorter than the re-search required time t, it is determined that the re-searched travel route cannot be guided at an appropriate timing even if the re-search is performed. The re-search is prohibited (S103). on the other hand,
If t ≦ T, it is determined that the re-search for the new moving route can be completed before the start of the route guidance, and the re-search is performed (S
104). In the present embodiment, the re-search required time t is described as a fixed value. However, the re-search necessary time t is appropriately selected according to the type (contents) of information affecting the currently valid travel route and the type of road on which the vehicle is currently traveling. You may make it. For example, when only the re-search of a part of the route is necessary depending on the content of the information, when the re-search of the entire route is required, when the number of links available for the route search is large or small, the re-search required time t
Is changed, the necessity of the re-search can be determined more appropriately.

As described above, the re-search is performed only when the route guidance can be performed at a timing when the driver can perform the driving operation with a margin, so that it is possible to reliably prevent the start of the route guidance.

In the embodiment, if the re-search processing is prohibited in spite of the fact that the information affecting the currently valid travel route is obtained, there is a traffic jam etc., but the re-search is not performed. May be provided to the driver by a display or voice. Also, when performing a re-search, the driver may be informed that the re-search has been performed due to traffic congestion or the like. Further, if the obtained traffic information is traffic congestion information or travel time information, the above processing is performed. If the obtained traffic information is regulation information such as traffic closure, the above processing is not performed. May be executed.

[0026]

According to the present invention, if route guidance has been started even if information which affects a currently valid travel route is obtained, the route guidance is validated and re-search processing is prohibited. The re-searching process for a new moving route is performed on the route after the route guidance that has been output. As a result, the route guidance being output is not interrupted, and the driver is not bothered or confused.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of a route guidance device to which a route search processing method according to an embodiment of the present invention is applied.

FIG. 2 is a flowchart illustrating a route search processing method according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating a route guidance start timing.

FIG. 4 is a partial flowchart for reflecting the time required for the re-search processing in the re-search necessity determination in the route search processing method according to the embodiment of the present invention.

[Explanation of symbols]

10 transceiver, 12 VICS ECU, 14 FM
Antenna, 16 receivers, 18 Navigation E
CU, 20 display, 22 audio output device.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01C 21/00 G08G 1/09 G08G 1/0969

Claims (2)

(57) [Claims] 1. A route search processing method used for a route guidance apparatus for searching for a travel route to a destination based on acquired information and performing route guidance at a predetermined distance before a branch point of the travel route, comprising: A route search processing method characterized in that re-search processing of a moving route performed by a subsequent change in information is prohibited at least after the start of the route guidance. 2. The route search processing method according to claim 1, wherein the re-search is prohibited from a point in time when the time required for the re-search processing is further advanced from the start of the route guidance.