JP2003097958A - Navigation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation device capable of correctly identifying a road where the vehicle exists. SOLUTION: The navigation device having a map matching means which identifies a matching road where the vehicle exists based on the position information of the vehicle and map information comprises a road information receiving means for receiving road information showing the congestion conditions of a road, a speed detecting means for detecting the speed of the vehicle, a matching degree detecting means for detecting the matching degree between the road information received by the road information receiving means and the vehicle's traveling speed detected by the speed detecting means, and a road determining means for determining a road where the vehicle exists based on the matching degree between the road information and the vehicle's traveling speed detected by the mating degree detecting means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device for guiding a vehicle to run, and more particularly to a matching technique for accurately identifying a road on which a vehicle is present when there is a road running in parallel.

[0002]

2. Description of the Related Art In a navigation device for searching a route of a vehicle or guiding a vehicle, first, a radio wave from a GPS satellite is received, and the position and traveling direction of the vehicle are detected from the signal.
When the radio wave from the GPS satellite cannot be received, it is complemented based on the distance sensor and the direction sensor. The position of this vehicle is compared (map matching) with the road position of the map information (road map) stored in the CD-ROM or DVD. For example, when there are a plurality of roads where vehicles may exist, a plurality of roads are extracted as matching candidate roads (hereinafter simply referred to as candidate roads), and the traveling direction (direction) of the vehicle and extension of each road are extracted. The smaller the deviation in the direction (direction) and the smaller the deviation between the position of the vehicle and the position of each road, the higher the map matching evaluation value A is assigned, and the road with the highest map matching evaluation value A is assigned to each candidate road. The first candidate road is defined as the first candidate road, and the road having the low map matching evaluation value A is sequentially defined as the second and third candidate roads. Then, it is determined that the vehicle is present on the first candidate road (matching road).

[0003]

In the conventional navigation device, it is considered that the vehicle is present on the road having the highest map matching evaluation value A by comparing the vehicle position information and the map information by map matching. is doing. However, if there are roads (co-located roads) that run side by side in close proximity, it is difficult to determine on which road the vehicle is located only by the map matching evaluation value A. For example, if an expressway and a general road are running in parallel in three dimensions, the two roads have the same position in the plane direction, only the vertical positions are slightly different, and the directions of both roads are the same. Because there is
Both roads have the same map matching evaluation value A. Therefore, even though the vehicle (own vehicle) is traveling on a highway, the vehicle is traveling on a general road (or vice versa), and the vehicle exists on the wrong road. Map matching occurs as if it were. When the route search is performed in such a state, there is a problem that the vehicle is guided to the wrong route and the driver is confused.

It is an object of the present invention to provide a navigation device which can correctly identify a road on which a vehicle is located.

[0005]

In order to achieve the above object, the present invention provides a navigation device equipped with a map matching means for specifying a matching road on which the vehicle exists based on the vehicle position information and map information. A road condition information receiving means for receiving road condition information indicating a congestion state of the road, a speed detecting means for detecting a traveling speed of the vehicle,
A fitness degree detecting means for detecting a fitness degree of the road situation information received by the road situation information receiving means and a traveling speed of the vehicle detected by the speed detecting means; and the road situation detected by the fitness degree detecting means. It is characterized in that a road judging means for judging a road on which the vehicle is present is provided based on the conformity between the information and the traveling speed of the vehicle.

Further, when the road determination means detects that the road condition information and the traveling speed of the vehicle have a high degree of conformity by the adaptability detection means, the vehicle is the information corresponding to the road condition information. When the vehicle is present on the road and the adaptability detecting unit detects that the adaptability of the road condition information and the traveling speed of the vehicle is low, the vehicle does not exist on the information applicable road corresponding to the road condition information. ,
It is characterized by determining that.

Further, the road judging means judges the road on which the vehicle exists only when there is a parallel road running in parallel with the matching road.

The road judging means judges the road on which the vehicle exists only when the road condition information receiving means can receive the road condition information on both the matching road and the parallel road. It is characterized by.

Further, when the parallel road exists, the road judging means has a low matching degree between the road condition information on the matching road and the traveling speed of the vehicle by the matching degree detecting means, and the matching degree. When it is detected by the detection means that the road condition information on the parallel road and the traveling speed of the vehicle are highly compatible, it is determined that the vehicle is present on the parallel road.

Further, the road judging means may judge whether the vehicle is on the matching road or the parallel running road, based on a plurality of detection results by the adaptability detecting means. It is a feature.

Further, the adaptability detecting means is adapted to detect the adaptability of the road condition information and the traveling speed of the vehicle every time the vehicle travels a predetermined distance.

Further, the adaptability detecting means detects the adaptability of the road condition information and the traveling speed of the vehicle each time a predetermined time elapses.

Further, when the road judging means judges that the vehicle is present on the parallel road, the vehicle position correcting means for correcting the position of the vehicle on the matching road to the position parallelly translated on the parallel road. It is characterized by having.

Further, when the road condition information received by the road condition information receiving means is road condition information older than the current time by a predetermined time or more, the suitability detecting means determines the road condition information and the vehicle. It is characterized in that the conformity of the traveling speed is not detected.

Further, in a navigation device equipped with a map matching means for identifying a matching road on which the vehicle exists based on the position information and the map information of the vehicle, the road condition receiving the road condition information indicating the congestion condition of the road. Information receiving means, speed detecting means for detecting the traveling speed of the vehicle, and adaptability for detecting the degree of conformity between the road condition information received by the road condition information receiving means and the traveling speed of the vehicle detected by the speed detecting means. Equipped with degree detection means,
The map matching means is characterized in that the road on which the vehicle exists is specified based on the compatibility of the road condition information detected by the compatibility detection means and the traveling speed of the vehicle.

Further, the map matching means, for each matching candidate road among a plurality of matching candidate roads estimated to have a vehicle based on the vehicle position information and the map information, the vehicle position information and the map information. Based on the map matching evaluation value A evaluated based on the above, and the matching degree between the road condition information and the traveling speed of the vehicle by the matching degree detecting means in the plurality of matching candidate roads, each matching candidate road is evaluated. The road on which the vehicle exists is specified based on the comprehensive evaluation value E together with the conformity evaluation value K thus obtained.

Further, the goodness-of-fit evaluation value K is determined by a cumulative goodness-of-fit evaluation value ΣK of the goodness-of-fit evaluation values of a plurality of stages corresponding to the goodness of fit detected a plurality of times by the goodness-of-fit detection means. It is what

[0018]

1 is a block diagram showing a configuration of a navigation device according to a first embodiment of the present invention. Hereinafter, description will be given with reference to the drawings.

Reference numeral 11 is a GPS receiver which receives radio waves from an artificial satellite (GPS satellite) and calculates position information, azimuth information and the like from the signals. Reference numeral 12 is a direction sensor such as a gyro sensor for detecting the traveling direction of the vehicle. Reference numeral 13 is a vehicle speed sensor for detecting the traveling speed (traveling distance) of the vehicle, which uses signals from a speedometer of the vehicle. Reference numeral 14 is a map database (map information) including a CD-ROM or a DVD storing map information and a reading device thereof. 2 is G
A process of identifying the own vehicle position based on the position information from the PS receiver 11, the direction information of the direction sensor 12, the traveling speed information of the distance sensor 13, and the map information of the map database 14, up to the registered (input) destination Process to search the travel route of
The control unit is composed of a microcomputer and associated RAM, ROM, and the like that performs a process of guiding a vehicle along the searched route, a process of searching a facility or the like based on a predetermined condition, and the like. Reference numeral 31 is an input unit including operation switches and the like for inputting a destination and performing registration. Reference numeral 41 denotes a display unit including a liquid crystal display panel for displaying a map (road) for guidance based on a signal from the control unit 2 and a drive circuit. Reference numeral 42 is a voice output unit for synthesizing a voice for guidance or a voice corresponding to an input character based on an instruction from the control unit 2 and performing voice guidance by a speaker or the like.

5 is VICS (Ve) such as traffic jam (road condition)
single Information Communica
A VICS receiver for receiving information on a road system and an FM receiving unit for receiving traffic information (road condition information) transmitted by an FM multiplex broadcast wave or a beacon wave from a base station, and an FM multiplex receive unit. In this embodiment, level 3 information of VICS information (information including the degree of congestion and position data) is used.

FIG. 2 is a flowchart of a process for determining the road on which the vehicle is carried out by the control unit 2 of the navigation system according to the first embodiment of the present invention. FIG. 3 is a diagram for explaining a VICS information / vehicle speed compatibility detection method and a road determination method on which a vehicle is present. FIG. 4 is an explanatory diagram of the conformity detection and the detection section. Hereinafter, description will be given with reference to the drawings.

First, the outline of the present embodiment will be described. It is determined whether or not the vehicle actually exists on the matching road obtained by collating the vehicle position information and direction information with the map information.
The determination is made based on the detection result of the compatibility between the CS information and the traveling speed of the vehicle (hereinafter referred to as vehicle speed). Normally, if the road is “smooth”, the vehicle speed will inevitably increase and “congestion” will occur.
If you do, the vehicle speed will slow down. As shown in FIG. 3, the VICS information is “successful” on the general road on which it is determined that the vehicle is present (running) by the map matching,
If the vehicle speed is slow (10 km / h), it is detected that the compatibility of the VICS information and the vehicle speed is low. On the other hand, if the VICS information is “congestion” on a parallel highway (assuming that there is a vehicle on the highway), the vehicle speed is slow (10 km / h), so the compatibility between the VICS information and the vehicle speed is high. Is detected as high. That is, from the detection result of the compatibility between the VICS information and the vehicle speed, the vehicle does not exist on the general road that is map-matched from the position information (including the direction information) and the map information, but on the parallel highway. It is more reasonable to think so. Further, in the case of a highway and a general road, the accuracy can be further increased by adding the speed limit information of the road.

If it is determined that the vehicle is not on the map-matched road (matching road) but on the parallel road from the detection result of the VICS information and the matching degree of the vehicle speed, the vehicle is not necessary. Correct the position on the parallel road. In order to correct the vehicle position, as shown in FIG.
Corresponding to the second fitness detection), the virtual position of another (parallel) road is always created at the point where the current vehicle position is translated to the other road side as it is, and the fitness is set for each of the vehicle position and the virtual position of another road. To detect. Then, as a result of the detection (nth-time adaptability detection), when it is necessary to correct the vehicle position, the vehicle position is corrected to a previously created different road virtual position.

Next, a method of determining the road on which the vehicle is located will be described with reference to the flowchart of FIG. In step S11, the position and traveling direction of the vehicle are detected, and the process proceeds to step S12. That is, the GPS receiver 11, the direction sensor 12, and the vehicle speed sensor 13 detect the position and traveling direction of the vehicle. In step S12, the first candidate road (matching road) is estimated by collating with the map database, and the process proceeds to step S13. That is, the detected vehicle position and heading, and the roads (first, second ...
.. Estimate the vehicle position on the road (road number) with the smallest deviation by comparing the distance with the candidate road) and the direction of each road.

In step S13, it is determined whether there is a parallel road, and if there is a parallel road, the process proceeds to step S14.
If there is no parallel road, the process ends. The parallel road is a road whose map matching evaluation value is substantially the same as the evaluation value of the first candidate road among the roads that have been selected as the second candidate (third candidate is acceptable) at the time of map matching. A highway constructed on top of an open road (general road) or a general road running in parallel in close proximity. When performing map matching, if the map matching evaluation values of the first candidate road and the roads below the second candidate are extremely different, it is determined that there is no parallel road.

In step S14, it is determined whether or not the VICS information can be received on both roads. If the VICS information can be received, the process proceeds to step S15, and if the VICS information cannot be received, the process ends. That is, the matching road (first
VI for candidate roads) and parallel roads (second candidate roads, etc.)
Whether or not the CS information can be received by the VICS receiver 5 is determined, and the VICS information may be information that has been received and stored in advance as long as the information is within a predetermined time. V
The ICS information has three levels from level 1 to level 3,
The navigation device of the present invention utilizes Level 3 information. This level 3 information contains information on traffic jams, regulations, etc., and the number of the road on which the traffic jams and regulations have occurred. It is collated with the road number contained in the map data to check for traffic jams, regulations, etc. Is displayed on the map. still,
VIC received (or previously received and stored)
If the S information is information that is older than the current time by a predetermined time (for example, 1 hour) or more, the road condition (congestion condition) according to the VICS information may be different from the actual road condition, resulting in an erroneous determination (road condition). VIC so as not to specify)
Judge that there is no S information. Further, in this example, when the VICS information is provided only to one of the roads, the compatibility of the VICS information and the vehicle speed can be detected only for one of the roads, so it is determined that the reception is impossible (N). VI
It is also possible to judge based on the conformity between the CS information and the vehicle speed (the road is high when the conformity is high, and the reverse road when the conformity is low).

In step S15, the vehicle speed is detected and the process proceeds to step S16. That is, the speed sensor 13 detects the speed of the vehicle. In addition, temporary fluctuations in vehicle speed (for example,
In order to prevent erroneous judgments due to temporary acceleration, deceleration, etc. for adjusting the inter-vehicle distance from the preceding vehicle, it is desirable to adopt an average speed for a predetermined time.

In step S16, the matching degree between the VICS information and the vehicle speed is detected on the matching road, and step S16 is executed.
Move to 17. In other words, on the road where the vehicle is currently estimated to exist by map matching (the road with the highest map matching evaluation value), the matching degree between the received VICS information (“successful”, “congestion”, etc.) and the vehicle speed is calculated. To detect. If the VICS information is “successful” and the vehicle speed is “fast”, V
When the ICS information is "congestion" and the vehicle speed is "slow", it is detected that the degree of conformity is high. In addition, VICS information is "good"
If the vehicle speed is "slow", the VICS information is "traffic jam", and the vehicle speed is "fast", it is detected that the compatibility is low. Figure 3
In the example, the VICS information on the general road is “successful”
Since the vehicle speed is “slow” at 10 km / h, it is detected that the compatibility is low. In step S17, V on the parallel road
The conformity between the ICS information and the vehicle speed is detected, and the process proceeds to step S18. That is, the matching degree between the received VICS information and the vehicle speed is detected on the road running in parallel with the matching road. In the example of FIG. 3, VI on a parallel highway
CS information is "congestion" and vehicle speed is "slow" at 10 km / h.
Therefore, it is detected that the degree of conformity between the VICS information and the vehicle speed is high.

In step S18, it is determined whether or not the matching degree between the VICS information on the matching road and the vehicle speed is high. If the matching degree is high, the process proceeds to step S22, and if the matching degree is low, the process proceeds to step S19. This determination is determined by the detection result of step S16.

In step S19, the VIC on the parallel road
It is determined whether or not the S information and the vehicle speed have a high degree of conformity, and if the degree of conformity is high, the process proceeds to step S20, and if the degree of conformity is low, the process proceeds to step S24. This determination is determined by the detection result of step S17. In step S20, it is determined that the vehicle is on the parallel road, and the process proceeds to step S21. That is, judging from the received VICS information and the detection result of the matching degree of the vehicle speed, the matching degree of the own vehicle is assumed to be present on the parallel road rather than the matching degree with the road estimated by the map matching. Since it is higher, the vehicle is judged to be on the parallel road. In step S21, the vehicle position is corrected to the parallel road, and the process ends. As shown in FIG. 4, the position to be corrected is the position parallelly moved from the vehicle position on the matching road (first candidate road) to the parallel road (second candidate road). Note that when the vehicle position is corrected, the vehicle position is not corrected based on the detection result of the compatibility once, but the detection of the compatibility of the VICS information and the vehicle speed is performed at predetermined time intervals (or at predetermined travel distances). The vehicle position is detected at a time point when it is detected that the fitness on the parallel road is obviously higher than the other times (for example, when the fitness on the parallel road is detected several times in succession). It may be modified. By deciding whether or not to correct the vehicle position based on the results of multiple detections, errors due to temporary fluctuations in vehicle speed (for example, temporary acceleration and deceleration due to adjustment of the inter-vehicle distance from the preceding vehicle) Modification can be prevented.

In step S22, the VIC on the parallel road
It is determined whether or not the degree of conformity between the S information and the vehicle speed is high, and if the degree of conformity is high, the process proceeds to step S24, and if the degree of conformity is low, the process proceeds to step S23. This determination is determined by the detection result of step S17. In step S23, it is determined that the vehicle is present on the matching road, the position of the vehicle is determined, and the process ends. That is, since the degree of conformity between the received VICS information and the vehicle speed of the vehicle is high, it can be determined that the vehicle is on the road (first candidate road) estimated by map matching. Therefore, the vehicle position is not corrected.

In step S24, the determination of the road on which the vehicle is present is suspended and the process is terminated. That is, the VICS information regarding the road where the vehicle is estimated to exist (first candidate road or second candidate road) and the matching results of the vehicle speed on both roads are the same detection result (whether the matching ratio is high or both match). Since the conformity is low), the determination of the road on which the vehicle is present is suspended by detecting the conformity of the VICS information and the vehicle speed. In this case, the own vehicle is considered to be on the road estimated by map matching.

As described above, in the present embodiment, it is determined whether or not a vehicle is present on the road estimated by map matching based on position information (including direction information) and map information.
The degree of conformity between the received VICS information and the actual vehicle speed is detected, and even if there is a road running in parallel in the vicinity, the vehicle is also detected in the same degree of fitness for the parallel road. Improves reliability in identifying existing roads.

FIG. 5 is a flow chart of a matching candidate evaluation process performed by the control unit 2 of the navigation device according to the second embodiment of the present invention. FIG. 6 is an explanatory diagram of a matching candidate evaluation method. FIG. 7 is an explanatory diagram of a plurality of levels (adaptation levels) evaluation criteria of the adequacy. Hereinafter, description will be given with reference to the drawings. Note that the configuration of the navigation device according to this embodiment is the same as that of the first embodiment, so description thereof will be omitted.

First, the outline of the present embodiment will be described. In map matching, the position of the vehicle (including the direction) and the road position of the map information (including the direction) for multiple candidate roads
Is evaluated and a score (map matching evaluation value) corresponding to the degree of coincidence is added, and the map matching evaluation value is added with the compatibility evaluation value based on the detection result of the VICS information and the compatibility of the vehicle speed. It determines the existing road.

Map matching evaluation values E1 and E2 in consideration of the VICS information of the first and second candidate roads and the detection result of the matching degree of the vehicle speed are expressed by equations (1) and (2), respectively.

E1 = A1 + K1 Equation (1) E2 = A2 + K2 Equation (2) Here, E1, E2: VICS information and the detection result of the matching degree of the vehicle speed are considered. Map matching evaluation values for the first and second candidate roads.

A1, A2: Map matching evaluation values for the first and second candidate roads determined by the vehicle position / direction and map information.

K1, K2: Fitness evaluation values of the first and second candidate roads determined by the VICS information and the detection result of the fitness of the vehicle speed.

In the present embodiment, as shown in FIG. 6, it is assumed that a vehicle is on the first candidate road, and in this state, the vehicle position and map information are used for map matching and the VICS information and the vehicle speed are detected to be suitable. Based on the result, the judgment (evaluation) of the road on which the vehicle exists is started. And multiple times VIC
A cumulative evaluation value (ΣE) obtained by accumulating map matching evaluation values E1 and E2 in consideration of the detection result of the S information and the matching degree of the vehicle speed.
The first candidate road and the second candidate road are exchanged when (1, ΣE2) is reversed (reversed by a predetermined value or more so that it can be said that it is obviously reversed).

Next, the method of evaluating the map matching candidates will be described with reference to the flowchart of FIG. In step S31, the position and traveling direction of the vehicle are detected, and the process proceeds to step S32. That is, the GPS receiver 11, the direction sensor 12, and the vehicle speed sensor 13 detect the position and traveling direction of the vehicle. In step S32, the first candidate road is selected by collating with the map database, and the process proceeds to step S33.
That is, by comparing the detected vehicle position and traveling direction with the distance between each road in the map database 14 and the direction of each road,
The road (road number, position) with the smallest deviation is selected (the map matching evaluation value A1). Step S3
In 3, the second candidate road is selected by collating with the map database, and the process proceeds to step S34. That is, when the detected position and traveling direction of the vehicle are compared with the map database 14, the road having the next highest map matching evaluation value after the first candidate road is selected (the map matching evaluation value is A2). Usually, the first candidate road and the second candidate road are three-dimensionally parallel expressways and general roads, or two general roads that are parallel (parallel) close to each other. The values are similar (A1≈A2). still,
When there are no roads running in parallel, the map matching evaluation value A2 of the second candidate road becomes extremely lower than the map matching evaluation value A1 of the first candidate road, and V of the present embodiment is used.
It is not necessary to evaluate the map matching in consideration of the detection result of the matching degree between the ICS information and the vehicle speed, and the vehicle position is first
It is determined (determined) that the vehicle exists on the candidate road (this processing ends).

In step S34, the speed of the vehicle is detected and the process proceeds to step S35. That is, the speed sensor 13 detects the speed of the vehicle. In step S35, the VICS information of the first and second candidate roads is received, and the process proceeds to step S36. In other words, the first VICS receiver 5
The VICS information of the candidate road / the second candidate road is received.
In the present embodiment, if the VICS information cannot be received for both candidate roads or one of the candidate roads, the map matching evaluation in consideration of the detection result of the matching degree between the VICS information and the vehicle speed cannot be performed. The process ends (as before, the road on which the vehicle is located is identified by map matching based on the vehicle position / travel direction and map information), but one of the VICS information and the vehicle speed detects the degree of conformity,
It is also possible to add a value corresponding to the goodness of fit to the map matching evaluation value if the goodness of fit is high, or subtract a value according to the goodness of fit from the map matching evaluation value if the goodness of fit is low.

In step S36, the compatibility of the VICS information and the vehicle speed is detected for the first candidate road, and step S3 is executed.
Go to 7. That is, it is determined that the vehicle is on the first candidate road and the compatibility of the VICS information and the vehicle speed is detected. In the present embodiment, VICS information “congestion”, “congestion”,
The goodness of fit is detected by associating "smooth" with "high speed", "medium speed", and "low speed" of the vehicle speed. As shown in FIG. 7, for example, VICS information “congestion” and vehicle speed “low speed”, VIC
If the combination of “congestion” of the S information and “medium speed” of the vehicle speed, and “successful” of the VICS information and “high speed” of the vehicle speed, the matching degree is high and the evaluation score 3 is given. Also, VICS information “congestion” and vehicle speed “low speed”, VICS information “congestion” and vehicle speed “high speed”, VICS information “smooth” and vehicle speed “medium speed”, VICS information “congestion” and vehicle speed In the case of the combination of "medium speed", the compatibility is medium and the evaluation point 2 is given.
In addition, VICS information “congestion” and vehicle speed “high speed”, VI
If the combination of "successful" in the CS information and "low speed" in the vehicle speed is low, the degree of conformity is low, and an evaluation score of 1 is given. “Low speed” means less than 20 km / h on general roads and 30 k on highways.
less than m / h), "medium speed" means 20 km / h on a general road
Above 40 km / h, above 30 km / h on expressways and below 60 km / h, “high speed” means 40 km on general roads
/ H or more and 60 km / h or more for highways, and the threshold values are changed between highways and ordinary roads.

In step S37, the fitness evaluation value K1 is calculated for the first candidate road, and the process proceeds to step S38.
That is, the fitness evaluation value K1 is calculated from the evaluation points assigned according to the VICS information and the fitness of the vehicle speed, using the equation (3).

Goodness-of-fit evaluation value K1 = k × P1 (3) where k: constant P1: score given by the goodness of fit on the first candidate road (1 to 3 points) The compatibility of the VICS information and the vehicle speed is detected for the second candidate road, and the process proceeds to step S39. That is, it is determined that the vehicle is currently on the second candidate road, and the compatibility of the VICS information and the vehicle speed is detected. The detection method is the same as that in step S36, and therefore its description is omitted.

In step S39, the fitness evaluation value K2 is calculated for the second candidate road, and the process proceeds to step S40.
That is, the fitness evaluation value K2 is calculated from the evaluation points assigned according to the VICS information and the fitness of the vehicle speed, using the equation (4).

Goodness-of-fit evaluation value K2 = k × P2 (4) where k: constant P2: score given by the goodness of fit on the second candidate road (1 to 3 points) The cumulative evaluation value difference Σ (E2-E1) is determined whether or not the cumulative evaluation value difference Σ (E2-E1) is equal to or more than a predetermined value.
2-E1) is greater than or equal to the predetermined value, the process proceeds to step S42, and if the cumulative evaluation value difference Σ (E2-E1) is less than the predetermined value, the process proceeds to step S41. In other words, the cumulative evaluation value difference ΣE2 of the second candidate road from the start of the evaluation (including map matching and the VICS information and the matching degree of the vehicle speed) is a predetermined value (clearly the difference is larger than the cumulative evaluation value difference ΣE1 of the first candidate road. It is to judge whether or not the value has become greater than or equal to the value considered to be).

In step S41, it is judged whether or not the vehicle has traveled a predetermined distance, and if the vehicle has traveled a predetermined distance, step S3
Return to 1 and stand by if the vehicle does not travel a predetermined distance. That is,
As shown in FIG. 6, the map matching evaluation and the fitness evaluation are performed multiple times each time the vehicle travels a predetermined distance. Instead of performing the fitness evaluation each time the vehicle travels a predetermined distance, it may be performed each time a predetermined time elapses.

In step S42, the process of changing the vehicle position from the matching road (first candidate road) to the second candidate road is completed. That is, considering not only the map matching evaluation values A1 and A2 corresponding to the position of the vehicle but also the fitness evaluation values K1 and K2 determined by the fitness of the VICS information and the vehicle speed, the cumulative evaluation value E1 of the first candidate road is higher than the cumulative evaluation value E1. The cumulative evaluation value E2 of the second candidate road is higher than a predetermined value (a value that is considered to be obviously different). Therefore, as shown in FIG. 7 (corresponding to the n-th evaluation), the matching road is replaced with the second candidate road. When two roads are running in close proximity to each other, the map matching evaluation values A1 and A2 are similar to each other. Therefore, the matching results of the first candidate road and the second candidate road are detected, and each time the both candidate roads are detected. The larger the evaluation point differences k1 and k2 are, the shorter the cumulative evaluation value difference Σ will be (or the shorter mileage).
(E2-E1) becomes larger than a predetermined value, and the time is short (the number of times of repeating steps S31 to S41 is small).
It is replaced with the second candidate road. The position of the vehicle is the second
When the candidate road is replaced, in the subsequent processing, the second candidate road is regarded as the first candidate road, and this processing is continuously executed.

As described above, in the present embodiment, when one road is specified from a plurality of matching candidate roads, the matching degree between the VICS information and the vehicle speed is detected on each matching candidate road, and the matching degree which is the detection result is detected. Since the road on which the vehicle exists is determined based on the comprehensive evaluation value obtained by adding the evaluation value to the vehicle position information and the map matching evaluation value based on the map information, the reliability of identifying the road is improved.

[0051]

As described above, according to the present invention, the road on which the vehicle exists is specified based on both the map matching and the matching detection of the VICS information and the vehicle speed.
It is possible to provide a navigation device with improved reliability for identifying a road on which a vehicle exists.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a navigation device according to a first embodiment of the present invention.

FIG. 2 is a flowchart of a process for determining a road on which a vehicle is present, which is performed by the control unit 2 of the navigation device according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining a method of detecting a compatibility between VICS information and a vehicle speed and a method of determining a road on which a vehicle exists.

FIG. 4 is an explanatory diagram of fitness detection and a detection section.

FIG. 5 is a flowchart of matching candidate evaluation processing performed by the control unit 2 of the navigation device according to the second embodiment of the present invention.

FIG. 6 is an explanatory diagram of a matching candidate evaluation method.

FIG. 7 is an explanatory diagram of a plurality of levels (adaptation levels) evaluation criteria of the adequacy.

[Explanation of symbols]

11 ... ・ GPS receiver, 31 ... Input section, 12 ... Direction sensor, 41 ...
..Display units, 13 ... Distance sensors, 4
2 ... Voice output unit, 14 ... Map database, 5 ... VICS receiver, 2 ...
Control unit.

Claims (13)

[Claims] 1. A navigation device having map matching means for identifying a matching road on which the vehicle is present based on vehicle position information and map information, and a road condition for receiving road condition information indicating a road congestion condition. Information receiving means, speed detecting means for detecting the traveling speed of the vehicle, and adaptation for detecting the degree of conformity between the road condition information received by the road condition information receiving means and the traveling speed of the vehicle detected by the speed detecting means. And a road determining means for determining a road on which the vehicle is present based on the compatibility of the road condition information detected by the compatibility detecting means and the traveling speed of the vehicle. Navigation device. 2. The road judging means, when the conformity detecting means detects that the conformity between the road condition information and the traveling speed of the vehicle is high, the vehicle corresponds to the information corresponding to the road condition information. When the vehicle is present on the road and the adaptation degree detection means detects that the adaptation degree of the road condition information and the traveling speed of the vehicle is low, the vehicle does not exist on the corresponding information road to which the road situation information corresponds. The navigation device according to claim 1, wherein the navigation device is determined to be. 3. The navigation device according to claim 1, wherein the road determination means determines the road on which the vehicle exists only when there is a parallel road that runs in parallel with the matching road. 4. The road judging means judges the road on which the vehicle exists only when the road condition information receiving means can receive the road condition information on both the matching road and the parallel road. The navigation device according to claim 3, wherein: 5. The road judging means, when the parallel road is present, has a low matching degree between the road condition information and the traveling speed of the vehicle on the matching road by the matching degree detecting means, and the matching degree. 4. The vehicle according to claim 3, wherein when the detection means detects that the road condition information on the parallel road and the traveling speed of the vehicle are highly compatible, it is determined that the vehicle is present on the parallel road. Item 4. The navigation device according to item 4. 6. The road judging means, based on a plurality of detection results by the conformity detecting means,
The navigation device according to claim 2 or 5, wherein it is determined whether the vehicle is on the matching road or the parallel road. 7. The conformity detecting means detects the conformity between the road condition information and the traveling speed of the vehicle each time the vehicle travels a predetermined distance. Navigation device. 8. The adaptability detecting means detects the adaptability of the road condition information and the traveling speed of the vehicle every time a predetermined time elapses.
7. The navigation device according to claim 6. 9. A vehicle position correcting means for correcting the position of the vehicle on the matching road to a position parallelly translated on the parallel road when the road judging means judges that the vehicle is present on the parallel road. The navigation device according to claim 3, further comprising: 10. If the road condition information received by the road condition information receiving unit is road condition information older than a current time by a predetermined time or more, the suitability detecting unit detects the road condition information and the vehicle. 2. The navigation device according to claim 1, wherein the fitness of the traveling speed of the vehicle is not detected. 11. Based on vehicle position information and map information,
In a navigation device equipped with a map matching means for specifying a matching road on which the vehicle exists, a road condition information receiving means for receiving road condition information indicating a congestion state of the road, and a speed detecting means for detecting a traveling speed of the vehicle. The map matching unit includes a fitness detection unit that detects the fitness of the road condition information received by the road condition information receiving unit and the traveling speed of the vehicle detected by the speed detecting unit. A navigation device, characterized in that the road on which the vehicle is present is specified based on the compatibility between the road condition information detected by the means and the traveling speed of the vehicle. 12. The map matching means, for each matching candidate road among a plurality of matching candidate roads estimated to have a vehicle based on the vehicle position information and the map information, the vehicle position information and the map information. Based on the map matching evaluation value A evaluated based on the above, and the matching degree between the road condition information and the traveling speed of the vehicle by the matching degree detecting means in the plurality of matching candidate roads, each matching candidate road is evaluated. 12. The navigation device according to claim 11, wherein the road on which the vehicle is located is specified based on a comprehensive evaluation value E together with the conformity evaluation value K thus obtained. 13. The goodness-of-fit evaluation value K is a cumulative goodness-of-fit evaluation value ΣK of the goodness-of-fit evaluation values K of a plurality of stages corresponding to the goodness-of-fit detected a plurality of times by the goodness-of-fit detection means.
13. The navigation device according to claim 12, wherein the navigation device is determined by