JP3268634B2 - Route search device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route search device for determining a recommended route from a departure point or a current position to a destination.

[0002]

2. Description of the Related Art In a navigation system such as a vehicle, a conventional route search device that determines a recommended route from a departure point or a current position to a destination T by performing a route search calculation and determines the current position obtained by an own vehicle position calculation processing device, Recommended from the starting point where an arbitrary point on the electronic map shown on the display device is input from the input device to the destination where the arbitrary point on the electronic map also shown on the display device is input from the input device. The method of calculating a route by the Dijkstra method or the potential (labeling) method includes a method of calculating a shortest distance route based on “distance data” included in a road network recorded in a map database, and a method of calculating a route in a map database. Recorded "distance data", "road width data",
There is a method for calculating the shortest time route based on travel time cost parameters such as "lane number data", "road type data (high speed, national road, general, etc.)", "speed limit data" and the like.

FIG. 7 is a schematic view of a route for explaining an example of a result of a distance-first search performed by a conventional route searching device. In the figure, a thin solid line indicates a general road, and a thick solid line indicates a national road. As a result of a search calculation for obtaining the shortest distance, a link a to m from the departure point S to the destination T is a → b →
This indicates that a route passing through each link of e → l → m → h → j has been obtained.

FIG. 8 is a schematic view of a route for explaining an example of a time-first search result in a conventional route search device. In the figure, a thin solid line indicates a general road, and a thick solid line indicates a national road. As a result of a search calculation for obtaining the shortest time, a recommended route is selected from links a to m from the departure point S to the destination T as a → d → k. → l → m → h → j indicates that a route has been obtained.

FIG. 9 is a schematic view of a route for explaining another example of the distance priority search result in the conventional route search apparatus. The route for explaining an example in which the route in front of the station is included in the route of the search result. It is a schematic diagram. In the figure, a thin solid line indicates a general road, and a thick solid line indicates a national road. As a result of a search calculation for finding the shortest distance, links a 'to o' from the starting point S to the destination T are shown.
A '→ b' → e '→ h' →
This indicates that a route passing through each link of i ′ → l ′ → o ′ has been obtained.

FIG. 10 is a schematic diagram illustrating another example of the result of the time-first search performed by the conventional route searching apparatus. FIG. 10 is a schematic diagram illustrating an example in which the searched route includes a station-front road. It is. In the figure, a thin solid line indicates a general road, and a thick solid line indicates a national road.
From the links a 'to o' from the departure point S to the destination T, the recommended route is a '→ d' → g ′ → h ′ → i ′ →
This indicates that a route passing through each link of l ′ → o ′ has been obtained.

[0007]

By the way, the shortest time route calculated by using data such as the road width, the number of lanes, the road type, the speed limit, and the like has priority on a national road over a general road and on an expressway over a national road. The result to use is obtained. (See FIGS. 7 and 8, or FIGS. 9 and 10.) However, in many cases, the national roads and highways are more congested than the general roads. Therefore, the calculated recommended route should ideally be able to reach the destination in the shortest time, but may not actually be able to reach the destination in the shortest time.

In addition, as shown in FIG. 10, when there is a railway station along some roads in the search route, the road (link; c ') in front of the station is often congested. If the shortest route calculated is the road (link;
When c ′) is included, if the vehicle actually travels, it may get caught in the road congestion in front of the station, so that it may not be possible to reach the destination in the shortest time.

An object of the present invention is to provide a route search device which solves the above-mentioned conventional problems.

[0010]

Route searching apparatus according to the present invention SUMMARY OF THE INVENTION are recommended in the route search device for performing route by calculating a recommended route to the destination induction, the cost parameters preset travel time from the starting point During the search calculation process to search for a route, the travel time cost parameter
A recommended route is obtained based on the meter, and the changed travel time cost parameter is restored to a preset travel time cost parameter at the end of the search , and the restored original preset time is used.
Recommended route using defined travel time cost parameters
And calculating means for calculating the total travel time cost for

[0011] In addition, the route search device according to the present invention, out
Calculate the recommended route from the departure point to the destination and perform route guidance
Total route for recommended route
The calculating means for calculating the line time cost includes at least two types of first and second roads used in the calculation,
A first road having a predetermined high first average speed travel time cost parameter and a predetermined low second
In the calculation process of obtaining the recommended route, the travel time cost parameters of the respective average speeds with the second road having the travel time cost parameter of the average speed are replaced and changed, and the recommended route that is the obtained search result is obtained. the first and travel time cost parameter of the average speed of the second road to restore the preset mean rate during, was the restoration
Using the original preset travel time cost parameters
To calculate the total travel time cost for the recommended route .

Further, in the route search device according to the present invention, the calculation means calculates the travel time cost parameter by adding the cost relating to the station forward entry direction.

[0013]

In a route search apparatus that calculates a recommended route from a departure point to a destination and performs route guidance, a preset travel time cost parameter is changed during a search calculation process,
The changed travel time cost parameter is restored to a preset travel time cost parameter at the end of the search to calculate the total travel time cost. In this way, the current
It becomes easy to obtain a recommended route that really suits .

Further, the travel time cost parameter is calculated by adding the cost relating to the station forward entry direction. Even if a general road or narrow road is used as a search result when searching for a bypass route, it is difficult to use the road in front of the station, so the possibility of time consumption due to congestion in front of the station can be eliminated, and a more practical route route can be found. .

[0015]

FIG. 1 is a block diagram showing an embodiment of a route search device according to the present invention. In FIG. 1, 1
Is a main controller composed of a microcomputer or the like, 2 is a vehicle position processing device, 3 is a map database, 4
Is a storage medium reading device, 5 is a main storage memory, 6 is an input device, 7 is a video processing device, and 8 is an audio output device.

The own-vehicle position processing device 2 comprises an autonomous navigation sensor 2a, a GPS receiver 2b, and an own-vehicle position calculation device 2c. The own vehicle-related sensor information from the autonomous navigation sensor 2a and the GPS from the GPS receiver 2b are provided. The own vehicle position is calculated by the own vehicle position calculation device 2c based on the current position information of the own vehicle by the satellite radio wave reception. The storage medium reader 4 is a CD-R
The map data is read from the map database 3 such as OM and supplied to the main controller 1.

The main controller 1 relates to the map data from the storage medium reading device 4, the current position data of the own vehicle from the own vehicle position processing device 2, and the departure place and destination of the own vehicle input from the input device 6. A recommended route is calculated based on the position data, and the obtained recommended route data is stored in the main storage memory 5. Also, the main controller 1
The recommended route data is read from the main storage memory 5 and supplied to the video processing device 7. The video processing device 7 includes a graphic controller 7a, a video RAM 7b, and a display device 7c.
The recommended route data is stored in the video RAM 7b by the graphic controller 7, and the recommended route data read from the video RAM 7b is supplied to the display device 7c and displayed on the display screen.

In the above configuration, when the shortest time route is calculated using the data such as the road width, the number of lanes, the road type, and the speed limit, for example, when calculating based on the road type data, conventionally, A travel time cost parameter having an average speed set in advance as described below is used for each road type. (Average speed of travel time cost parameter) Expressway 70 km / h Car-only road 50 km / h National highway 40 km / h Prefectural road 30 km / h General road 20 km / h It is set so that the average speed gradually decreases in the direction. Therefore, there is a tendency to select a road having an average speed as high as possible when calculating the time priority route search.

Therefore, in the present invention, the average speed (initial value) of this conventional preset travel time cost parameter is set.
Is changed so that the average speed is sequentially increased from the expressway to the general road as described below, and this set value is used as a travel time cost parameter at the time of time priority search calculation. (Set value of travel time cost parameter after change) Expressway 20 km / h Automobile road 30 km / h National highway 40 km / h Prefectural road 50 km / h General road 70 km / h

When the time priority search calculation is performed based on the travel time cost parameter thus changed, a result is obtained in which the national road is used from the expressway and the general road is used from the national road. This is particularly noticeable when there are general roads running parallel to expressways and national roads. Since the travel time cost of the obtained search result is meaningful only during the calculation,
Next, the travel time cost parameter is returned to the original initial value, only the cost of the search result is changed, and the search is terminated.

Next, the time priority route search procedure of the present invention will be described with reference to the flowchart shown in FIG. First, step S
At 1, the search is started by operating the search command key of the input device 6, and then at S2, the main controller 1 acquires the position information of the starting point P and the destination T from the map database 3 via the storage medium reading device 4. I do. Then in S3,
The main controller 1 similarly converts the average speed data (initial value) of the travel time cost parameter corresponding to each road type obtained from the map database 3 through the storage medium reading device 4 from the expressway to the general road as described above. In step S4, a search for a recommended route is calculated based on the set value of the average speed of the changed travel time cost parameter. Then, in step S5, the search result sequence is changed. create.

Next, in step S6, an initial travel time cost parameter is restored for each road type constituting the recommended route in the search result sequence. Then, in step S7, the recommended route is determined based on the restored initial travel time cost parameter. Is calculated, and finally the calculation result is output in S8.

FIG. 3 is a schematic route diagram illustrating an example of a time-first search result obtained by the above procedure on the same road map as in FIG. In FIG. 4, a thin solid line indicates a general road, and a thick solid line indicates a national road. As a result of a search calculation for obtaining the shortest time, from the links a to m from the starting point S to the destination T, a → b → This indicates that a route passing through each link of c → f → g → i → j has been obtained.

FIG. 4 is a schematic route diagram illustrating an example of a time-first search result obtained by the above procedure on the same road map as that of FIG. In the figure, a thin solid line indicates a general road, and a thick solid line indicates a national road. As a result of a search calculation for obtaining the shortest time, a recommended route is selected from links a 'to o' from the departure point S to the destination T as a '→ b '→ c' →
This indicates that a path has been obtained that passes through links f ′ → k ′ → n ′ → o ′.

As can be seen from the comparison of FIGS. 3 and 8 and FIGS. 4 and 10, the results of using the national road from the expressway and the general road from the national road are obtained. Has an effect as a loophole search. Further, when there is no expressway or national road in the vicinity, it is no longer necessary to pull into the national road or expressway as in the related art.

In the above description, the average speed of the travel time cost parameter is changed, but the same calculation can be performed based on road width data, lane number data, speed limit data, and the like.

[0027]

In a conventional route search in which the travel time cost parameter is not consciously manipulated as in the prior art, the search results proceed from a general road to a national road, and from a national road to a highway in order from a wide road. Unless the destination is near the station, it will not pass through the station. In addition, as described above, if the route search is performed by consciously changing and setting the travel time cost parameter in the calculation process, it is certain that the result of a runaway search that uses a national road from an expressway and a general road from a national road. However, in general, there is a railway station along such a search result road, and when the vehicle actually runs, it is caught in the road congestion in front of the station, so that it may not be an effective way.

Therefore, as another embodiment of the present invention, a cost is provided in the direction of approaching the station at the intersection of the road reaching the station, thereby making it difficult to enter the station. For example, a common restriction code that specifies the entry into the station and is unique to the vendor is provided in the inter-link restriction record of the route search data, and it is set that the passage takes a predetermined time (for example, 5 minutes). As described above, the cost for the predetermined time is added in the approach direction to the station front road, so that the cost tends to avoid the station front road due to the existence of this cost at the time of calculating the shortest time route search. If used as a station road (link;
c ') becomes difficult to use.

Next, the procedure of the intersection cost processing for a certain link during the search calculation in the other embodiment shown in FIG. 5 will be described. First, in step S11, the main controller 1 determines whether or not there is a connection destination link. If yes, proceed to S12, and if no, end the operation. In S12, the main controller 1 determines whether or not there is inter-link regulation. If yes, proceed to S13; if no, proceed to S1.
Return to 1. In S13, the main controller 1 determines whether or not to enter the station. If the answer is yes, the process proceeds to S14, where a predetermined time (for example, 5 minutes) is added as a cost, and then S11
Return to If the answer to S13 is NO, the process proceeds to S15, where the type of road is determined, the impassability process is performed, and then the process returns to S11.

FIG. 6 is a schematic route diagram illustrating an example of a time-first search result obtained by the above-described procedure on the same road map as in FIG. In the figure, a thin solid line indicates a general road, and a thick solid line indicates a national road. As a result of a search calculation for obtaining the shortest time, links a 'to o' from the starting point S to the destination T are shown.
A '→ b' → e '→ j' →
This indicates that a route passing through each link of m '→ n' → o 'has been obtained.

As can be seen from a comparison between FIG. 6 and FIG. 4, even if a general road or a narrow road is used as a search result when searching for a bypass route, it is difficult to use the station front road (link; c '). As a result, the possibility of time consumption due to congestion in front of the station can be eliminated, and a more practical escape route can be obtained. Of course, it is not impossible to pass because it only adds a few minutes to the passage, so the departure place (current location) in front of the station
You can search even if there is a destination. If the station advance control code is ignored during a time when the station will not be crowded, such as late at night or early morning, a normal cost route search can also be performed.

It is to be noted that a search result that is difficult to pass through a railroad crossing can be calculated by similarly providing a railroad crossing approach control code at the railroad crossing and providing a cost.

[0033]

According to the route search device of the present invention,
A more practical route search without actual operation
Can be done .

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a route search device of the present invention.

FIG. 2 is a flowchart illustrating a route search procedure in the block diagram of FIG. 1;

FIG. 3 is a schematic route diagram illustrating an example of a route search result according to the procedure of FIG. 2;

FIG. 4 is a schematic route diagram illustrating another example of a route search result according to the procedure of FIG. 2;

FIG. 5 is a flowchart illustrating a route search procedure in another embodiment of the route search device of the present invention.

FIG. 6 is a schematic diagram illustrating a route search result according to the procedure of FIG. 5;

FIG. 7 is a schematic route diagram illustrating a result of a distance-first search performed by a conventional route search device.

FIG. 8 is a schematic route diagram illustrating a time-first search result in a conventional route search device.

FIG. 9 is a schematic route diagram illustrating an example in which a route in front of a station is included in the route obtained as a result of the distance priority search in the conventional route search device.

FIG. 10 is a schematic route diagram illustrating an example in which a road in front of a station is included in a route obtained as a result of a time-first search by a conventional route search device.

[Explanation of symbols]

 Reference Signs List 1 main controller 2 own vehicle position processing device 3 map database 4 storage medium reading device 5 main storage memory 6 input device 7 video processing device 8 audio output device 2a Autonomous navigation sensor 2b GPS receiver 2c Own vehicle position calculation device 7a Graphic controller 7b Video RAM 7c Display device

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-168995 (JP, A) JP-A-9-5100 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01C 21/00 G08G 1/0969 G09B 29/10

Claims (3)

(57) [Claims] 1. A route search apparatus for calculating a recommended route from a departure point to a destination and performing route guidance, wherein a travel time cost parameter set in advance is used for searching for a recommended route.
During the search calculation process, and the changed travel time cost
The recommended route is obtained based on the default travel time cost parameter , and the changed travel time cost parameter is restored to a preset travel time cost parameter at the end of the search .
Using the preset travel time cost parameter
A route search device comprising a calculating means for calculating a total travel time cost for the recommended route . 2. Calculate a recommended route from the departure point to the destination
In the route search device for performing route guidance and, in the recommended route
The calculation means for calculating the total travel time cost for
At least two types of first and second roads used in the calculation, a first road having a predetermined high first average speed travel time cost parameter and a predetermined low second road; mean and replaced change calculated together in the calculation process of the travel time cost parameters of the respective average speed obtained for a recommended route and the second road having a travel time cost parameters of the velocity, and the search results obtained in
Restoring the travel time cost parameter of the average speed of the first and second roads in the recommended route to a preset average speed ,
The restored original preset travel time cost parameter
A route search device for calculating a total travel time cost for the recommended route using a meter . 3. The route search device according to claim 1, wherein the calculation means calculates the travel time cost parameter by adding a cost relating to a station forward entry direction.