JP3440503B2 - Car route guidance device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a map database to plan a travel route from a current position of a vehicle to a predetermined travel destination. The present invention relates to a route guidance device for a vehicle that performs route guidance for a vehicle based on a route. 2. Description of the Related Art In recent years, a route guidance device (navigation device) has been mounted on an automobile in order to assist the vehicle in traveling on unfamiliar land. As disclosed in, for example, Japanese Patent Application Laid-Open No. 2-129800, this route guidance device generally plans a travel route from a current position of the vehicle to a predetermined travel destination by using a map database. The route guidance of the own vehicle is performed based on the performed traveling route. Further, the plan of the traveling route is such that the optimal traveling route that minimizes the traveling route loss (that is, the expected traveling obstruction factor such as the loss of the traveling time, the loss of the traveling distance, and the loss of the ease of traveling) is minimized. It is generally performed by searching from. For example, in the route guidance device described in the above publication, the shortest route that minimizes the required travel time from the current position of the vehicle to the travel destination is searched from the map database to perform the travel route planning. [0003] However, in the conventional route guidance device, route guidance is performed without considering refueling at all. There is a risk that it will. That is, for example,
If the driver notices that the fuel is running low when driving according to the above route guidance, but there is no refueling station on the planned travel route that can be reached with the remaining fuel, the route guidance will be continued. As long as the vehicle runs in accordance with the above, fuel runs out. On the other hand, in order to avoid running out of fuel, if the vehicle is deviated from the planned traveling route and runs by searching for a refueling station on its own without relying on the route guidance device, the route guidance device may be located on unfamiliar land. In view of the fact that the vehicle is often used, it is easily presumed that a considerable amount of time is lost due to the passage through the refueling station, and that the vehicle travels an unnecessary distance. When the vehicle deviates from the planned traveling route, an input operation for returning the vehicle to the planned traveling route is required. The present invention has been made in view of such circumstances, and it is possible to prevent running out of fuel during running beforehand and to reduce running route loss caused by refueling to avoid running out of fuel. It is an object of the present invention to provide a route guidance device for an automobile that can be minimized. [0005] A route guiding apparatus according to the present invention is arranged such that, when the remaining fuel is low, a traveling route that has already been planned is passed through a refueling station that can be reached with remaining fuel. The above-mentioned object is achieved by adopting a configuration in which a travel route replanning for changing to a travel route is performed. That is, as described in claim 1, travel route planning means for planning a travel route from the current position of the vehicle to a predetermined travel destination using a map database,
Route guidance means for performing route guidance of the vehicle based on the planned travel route, wherein the travel route planning means reduces the remaining fuel of the vehicle to a predetermined amount or less. When it becomes, first, a refueling station located in an area that can be reached with a second predetermined amount of fuel smaller than the remaining fuel is searched from the map database, and each of the searched refueling stations passes through the refueling station. If the traveling route via the stand is planned, and the number of refueling stations searched as a result is less than or equal to the predetermined number and the traveling time of each traveling route via each stand exceeds the predetermined time, the vehicle can be reached with the remaining fuel. The refueling station search and the travel route planning via the stand by expanding the search range to a suitable area, the route guidance means, Travel path loss among the serial planned plurality of stand over the travel path is configured to perform route guidance based on the stand via the travel route that minimizes, it is characterized in. As described above, route guidance is performed on the basis of the travel route planned by the travel route planning means. The travel route is replanned by the route planning means, whereby the planned travel route is changed to a via-stand travel route that passes through a refueling station that can be reached with the remaining fuel. In this case, the fuel can be supplied before the fuel runs out, so that the driver can be prevented from running out of fuel without paying any special attention to the remaining fuel.
In this case, the travel route replanning causes a travel route loss as compared to the originally planned travel route,
In order to avoid running out of fuel when the fuel level is low as compared to the conventional case, the vehicle deviates from the planned traveling route and does not rely on the route guidance device to search for the refueling station by itself and travels The traveling route loss can be significantly reduced, and an input operation for returning the vehicle to the planned traveling route, which is necessary when the vehicle deviates from the planned traveling route, becomes unnecessary. Route guidance can be facilitated. As described above, according to the present invention, running out of fuel during running can be prevented beforehand, and a running route loss caused by refueling for avoiding running out of fuel can be minimized. . [0009] As a specific method of the above-mentioned "re-planning of the traveling route", as described in claim 1, when the remaining fuel of the own vehicle becomes equal to or less than a predetermined amount, the vehicle enters an area reachable by the remaining fuel. A method is conceivable in which a certain refueling station is searched from a map database, and for each of the searched refueling stations, a traveling route via the station via the refueling station is planned. In this case, as described in claim 1, it is preferable that the route guidance unit performs the route guidance based on the stand-by traveling route that minimizes the traveling route loss among the plurality of re-planned traveling-by-stand traveling routes. . [0010] By the way, if the area for refueling station search from the map database is large, the number of refueling stations in the area also increases, and it takes a long time to search for and replan the traveling route via the stand. It is conceivable to set the target area to an area smaller than the area that can be reached with the remaining fuel. However, if the area is set in such a small area, the possibility of searching for an appropriate refueling station is reduced, and the traveling time required for the traveling route via the stand obtained by replanning the traveling route becomes extremely long. There is. In such a case, it is more preferable to increase the search target area by placing a greater emphasis on shortening the traveling time of the traveling route via the stand, rather than shortening the time required for replanning the traveling route. [0011] From such a viewpoint, as a specific method of the "re-planning of the traveling route", as described in claim 1, a method for re-planning the traveling route within an area that can be reached with a second predetermined amount of fuel smaller than the remaining fuel. Refueling station search and travel route planning via a stand are performed first.As a result, only when the number of refueling stations searched is less than a predetermined number and the travel time of each If the search range is expanded to the area that can be reached by using and the refueling station search and the travel route planning via the stand are performed, the time required for the travel route replanning is kept as short as possible, and the travel time on the travel route via the stand is required. Time can be reduced. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a vehicle route guidance apparatus according to the present invention. This route guidance device is a device mounted on an automobile, and as shown in the figure, a map database 12
, The localization device 14, the route planning device 16, the data processing device 18, the image output device 20, and the audio output device 22
, A remaining fuel sensor 24, and a fueling station search area determination device 26. The map database 12 is a database storing a wide range of road networks and other map data, and is accessible from the route planning device 16, the data processing device 18, and the refueling station search area determining device 26. The road network in the map database 12 is stored by a plurality of nodes (nodes such as intersections) and links (minimum units of the traveling road) connecting these nodes. The localization device 14 is a device for recognizing the current position of the vehicle, and is configured to recognize the current position of the vehicle by a known method using a GPS receiver, a gyro, a geomagnetic sensor, or the like. This localization device 14
Is output to the route planning device 16 and the data processing device 18. The route planning device 16 is capable of setting a travel destination by manual input, and plans a travel route from the current position of the vehicle to the set travel destination by using the map database 12. It has become. In this travel route planning, a process of obtaining an optimal travel route that minimizes a travel route loss from the current position of the vehicle to the travel destination by using a method such as the Dijkstra method is performed. The travel route loss is a cost set for each link and each node (that is, a time required for traveling through the link (travel time),
The road width of the link, the slope, the presence or absence of a pavement, the straightness at the node, the right turn, the left turn, and the like, which impair the ease of traveling) are calculated as cumulative values. The data processing device 18 is a device for performing data processing for route guidance of the own vehicle based on the traveling route planned by the route planning device 16, and sets the traveling route to a current vehicle traveling position. Accordingly, the route guidance is performed by sequentially presenting the route guidance to the driver. The presentation of the traveling route is performed by using the image output device 20 and the audio output device 22 to appeal to the driver's sight and hearing using images and sounds. When the remaining fuel of the own vehicle is equal to or less than a predetermined amount, the route planning device 16 changes the planned traveling route to a traveling route via a stand via a refueling station which can be reached with the remaining fuel. Route replanning is performed. When the remaining fuel of the own vehicle becomes equal to or less than a predetermined amount, the travel route replanning searches the map database 12 for a refueling station located in a predetermined area (this will be described later). Is to plan a traveling route via a stand via the refueling station. As in the above-described travel route planning, the process for determining the optimal travel route that minimizes the travel route loss from the current position of the vehicle to the travel destination is also performed in the travel route planning via the stand. The data processing device 18 performs route guidance based on the stand-based traveling route that minimizes the traveling route loss among the plurality of stand-based traveling routes re-planned by the route planning device 16. ing. The remaining fuel sensor 24 is a sensor for detecting the amount of remaining fuel of the own vehicle, and its detection data is output to a refueling station search area determining device 26. Refueling station search area determination device 26
When the remaining fuel f of the own vehicle becomes equal to or less than the predetermined amount f ₀ , the search target area of the refueling station in the map database 12 is determined in two stages. That is,
Based on the vehicle current position P _A at which the remaining fuel f of the vehicle has reached a predetermined amount f _0, a predetermined amount f areas A1 reachable in fuels _0, the half amount f _0/2 An area A2 that can be reached by fuel is calculated, and these are determined as search areas. The areas A1 and A2 determined in this way are output to the route planning device 16. Next, a specific method of replanning the traveling route by the route planning device 16 will be described with reference to a flowchart shown in FIG. 2 and a map shown in FIG. That is, when the remaining fuel f of the own vehicle becomes equal to or less than the predetermined amount f ₀ (step S1), and the search target areas A1 and A2 are determined (step S2), first, it is within the smaller area A2. All the refueling stations are searched from the map database 12 (step S3), and for each of the searched refueling stations, a traveling route via the station via the refueling station is planned (step S3).
4). The planning of the route via the stand is performed as follows. That is, as shown in FIG. 3, if the remaining fuel f becomes equal to or less than a predetermined amount f ₀ while the vehicle is traveling on the initially planned traveling route R in the direction of the arrow in the figure, the predetermined amount f ₀ with the self-vehicle current position point P _a became, and the travel route R and after setting an appropriate point P _B deviated in the travel destination side from the area A2 as the travel destination temporary area A2 All refueling stations G ₁
For each G _7, planning the stand via the travel route via this. In the figure, traveling routes other than the traveling route R initially planned are indicated by two-dot chain lines. It should be noted that the provisional traveling destination is set as a point deviating from the area A2 to the traveling destination side, because if it is set as a point in the area A2, a route traveling in the opposite direction to the original traveling destination is set. This is because there is a possibility of planning. As shown in FIG. 2, the number of the refueling stations searched is not more than a predetermined number (for example, 10), and the traveling time of each of the traveling routes through the stands is a predetermined time (for example, initially). If it exceeds the required time of the planned travel route R (a time longer than the required time of 30 minutes), the search target area is expanded to the area A1, and the refueling station search and the travel route planning via the stand are performed (step S).
5, S6, S7). The planning of the traveling route via the stand is performed in the same manner as the planning of the traveling route via the stand in the area A2. However, the point P _B is set as a travel destination provisional In this case, it is necessary to set at a point off the travel destination side from rather area A1 in the area A2. By expanding the search target area as described above, the possibility of obtaining a stand-by traveling route with less traveling route loss is increased. On the other hand, if the number of refueling stations is too large, it takes a long time to plan a traveling route via the stands. Therefore, only when the number of refueling stations searched in the area A2 is equal to or less than a predetermined number, the area to be searched is determined. Enlarge (Step S
5). Further, if a travel route via a stand having a short required time can be obtained by the travel route planning in the area A2, it is not necessary to extend the search target area and spend extra time on the travel route planning. Only when the required travel time of the via route exceeds the predetermined time,
The search target area is expanded (step S6). [0029] It should be noted that, by where to set the point P _B as a travel destination of the temporary nature of the stand via the travel route comes slightly different. In other words, if it is set to a point far away from the area A2 or the area A1 to the traveling destination side, the traveling route via the stand has less traveling route loss than the originally planned traveling route. , The amount of calculation increases, so that the time required for planning the traveling route via the stand increases. On the other hand, area A2 or area A1
If the distance is set to a point close to, the traveling route loss of the traveling route via the stand increases, but the amount of calculation at the time of planning decreases, so the time required for planning the traveling route via the stand becomes shorter. As described in detail above, in the present embodiment, the route guidance is performed by the data processing device 18 based on the traveling route planned by the route planning device 16, but the remaining fuel f of the own vehicle is reduced by a predetermined amount. when it becomes f ₀ below searches the refueling station within the fuel f _0/2 reachable area in A2 of the second predetermined amount of half the predetermined amount f ₀ from the map database 12, are these search refueling For each of the stands, a travel route via the stand via the refueling station is first planned, and as a result, the number of refueling stations searched is less than or equal to a predetermined number and the travel time required for the travel route via each stand is a predetermined time. If more than only extends the search range to a possible area reaches a predetermined amount f ₀ performs the refueling station search and the stand via the travel route planning, these replanning Route guidance is performed based on the stand-based travel route that minimizes the travel route loss among the plurality of stand-based travel routes that have been set, so that even if the vehicle is running in accordance with the route guidance without running out of fuel, Can be refueled, so that the driver can be prevented from running out of fuel without having to pay special attention to the remaining fuel, and the time required for re-planning the travel route is minimized. In addition, it is possible to minimize the travel route loss due to the travel route replanning.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of an automobile route guidance apparatus according to the present invention. FIG. 2 is a flowchart showing the operation of the above embodiment. Map shown [Description of symbols] 12 Map database 14 Localization device 16 Route planning device (running route planning means) 18 Data processing device (route guidance means) 20 Image output device 22 Voice output device 24 Remaining fuel sensor 26 Refueling station search area determination apparatus

Claims (1)

(57) [Claims 1] Travel route planning means for planning a travel route from a current position of the vehicle to a predetermined travel destination using a map database, and Route guidance means for performing route guidance of the own vehicle based on the vehicle, wherein the travel route planning means, when the remaining fuel of the own vehicle is less than a predetermined amount, first the remaining fuel A second predetermined amount of fuel less than the fuel
The refueling station within reachable area while searching from the map database in charge, for each of these retrieved refueling station plans to stand over travel path through the oil supply stand, is the result searched refueling
When the number of stands is equal to or less than the predetermined number and
When the required travel time of the route exceeds the specified time
The search range up to the area reachable with the remaining fuel
Expand the refueling station search and via the stand
The route guidance unit is configured to perform a traveling route planning, and the route guidance unit performs the route guidance based on the traveling route via the stand that minimizes the traveling route loss among the plurality of traveling routes via the planned stands. A route guidance device for an automobile, wherein the route guidance device is configured.