JP2012118028A - Road node position management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce inconvenience in various types of processing caused by a deviation between a position of a merging/outgoing node read from road information and a point of actually starting a merging/outgoing travel.SOLUTION: A road node position management system: acquires vehicle driving conditions including at least one of information on a driving control process that has a possibility of being performed in a prescribed zone after passing a merging/outgoing node as an intersection between a merging/outgoing link and a main road link in road information, a traveling history of the vehicle in the merging/outgoing node, and shape characteristics of the merging/outgoing node; and selects any one of a first correction process that corrects the merging/outgoing node to a position suited to a vehicle route guide process based on the vehicle driving condition, and a second correction process that corrects the merging/outgoing node to a position suited to a map matching process.

Description

  The present invention relates to a road node position management system that manages road nodes included in road information. This road node position management system uses route transition, map matching, vehicle control, and other processing as a reference point for the transition area between the main road and merging / exiting roads that exist on the travel route to reach the destination. The present invention can be applied to a vehicle navigation apparatus that performs the above.

  For example, Patent Document 1 describes a vehicle navigation system that provides travel guidance for a branch road in a special section having a branch point with an introduction lane that extends from a main lane such as an expressway or a main road to the branch road via the introduction lane. Has been. In this system, vehicle position information acquisition means for detecting a vehicle position, guide route calculation means for calculating a guide route from the vehicle position and a set destination, and an introduction lane that branches from the main line to a branch road through the introduction lane Special section detecting means for detecting a special section having an attached branch point from the guide route ahead of the vehicle position, introduction lane transition detecting means for detecting that the vehicle has shifted from the main line to the introduction lane of the special section, and A branch guidance unit that performs branch guidance for a branch point with an introduction lane, and that performs travel guidance for the branch road in response to the introduction lane shift detection unit detecting a shift of the vehicle to the introduction lane. ing. Therefore, in response to detecting the transition of the vehicle to the actual introduction lane, it is possible to provide travel guidance for the branch road before actually passing through the subsequent branch point with the introduction lane. The correct driving guidance for the vehicle can be given to the driver with a sufficient margin. However, in this technique, the next processing to be performed is performed appropriately based on the fact that the introduction lane transition detection means has detected the transition of the vehicle to the introduction lane, so that the next processing to be performed is appropriately performed. However, it does not serve as a starting criterion for processing to be performed before the vehicle moves to the introduction lane.

  Further, in an intersection area or the like, a marking line peculiar to an intersection exists as feature information, and a vehicle position recognition device that appropriately corrects the vehicle position using this is described in Patent Document 2. In this apparatus, vehicle position information acquisition means for acquiring vehicle position information representing the current position of the vehicle, road information acquisition means for acquiring road information, and target features included in the acquired image information around the vehicle. Image recognition means for performing image recognition processing, course change learning information storage means for storing course change learning information, and vehicle position correction means for correcting the vehicle position information based on the course change learning information are provided. . In the course change learning information, course change information that is generated by learning a past course change operation of the vehicle and that can identify a course change intersection that is an intersection where the course change operation of the vehicle has been performed, and the course change operation Information on distances from the recognition position of the target feature to the position where the vehicle's course change operation has been performed is included for the target feature that has been image-recognized earlier. Specifically, when the target feature is recognized by the image recognition unit, the vehicle position correcting unit is configured to detect the target based on the vehicle position information based on the course change learning information about the target feature. The vehicle position information is corrected so that a position that has traveled a distance indicated by the distance information from a recognized position of the feature coincides with a position in the road information of the course change intersection specified by the course change information. That is, it is possible to appropriately correct the vehicle position information using information obtained by learning the detection result of the past course changing operation of the vehicle and the image recognition result of the target feature before the detection. However, with this device, correction of the vehicle position information at the route change intersection is possible, but the node position included in the road information does not change. For this reason, for example, even if the start timing of the course changing operation at the intersection differs depending on the driver, guidance and control associated with the course changing operation are performed at the same timing. That is, the node position in the road information is used as being universally correct.

  In addition, when there is a nearby intersection, it was extracted from the road information in order to solve the problem that proper route guidance cannot be performed due to the error between the distance between the intersections obtained from the road information and the distance between the actual intersections. When the distance between the proximity guidance points is calculated and the calculated distance is less than the predetermined distance, the distance between the proximity guidance points in the road information is corrected to the distance between the actual proximity guidance points, and the corrected distance is used for guidance. A navigation device that creates information and performs guidance guidance is described in Patent Document 3. The correction in this device is a correction that eliminates the error between the distance between the intersections obtained from the road information and the actual distance between the intersections. Therefore, the correction is appropriate for each vehicle that travels with various traveling tracks depending on circumstances. It is difficult to make correct corrections.

JP 2009-109340 A (paragraph number 0005-0014, FIG. 1 and FIG. 2) JP 2009-8591 A (paragraph number 0008-0029, FIG. 1) JP 2008-286750 A (paragraph number 0004-0015, FIG. 3)

  For example, guidance control for merging / leaving driving and merging / leaving nodes related to merging / leaving nodes provided in the area between the main lane and the merging / leaving lane, and subsequent map matching control, etc. The exit trajectory is important. That is, in the guidance control for merging / leaving traveling, the point where the merging / leaving traveling is actually started is more important than the position of the merging / leaving node in the road information. For example, in the case of exit travel, for a vehicle (driver) who tends to exit toward the exit lane at a position ahead of the exit node position in the road information, exit based on the exit node position in the road information If guidance is given, the guidance timing will be too early. On the other hand, if a vehicle (driver) who tends to exit toward the exit lane at a position before the exit node position is provided with exit guidance based on the location of the exit node in the road information, the guidance timing is It will be too late.

  In addition, the travel locus calculated from the direction sensor, the distance sensor, and the like is compared with the road shape (specified by the link and the node) indicated by the road information, and the best matching road link and the position on the link are obtained. Also in map matching, the relationship between the actual travel locus and the road shape is important. However, in the area between the main lane and the merging / leaving lane, the running trajectory when merging / leaving is performed also varies depending on the road shape and the driving tendency of the driver. The position of the exit node and the extension direction of the joining / exiting link may be greatly different from the actual travel path of joining / exiting. For example, if a vehicle has joined and exited at a crossing angle that is significantly different from the intersection angle between the joining and leaving link extending from the joining and leaving node in the road information and the main line link, the vehicle is running along the joining and leaving link. The map matching process may be prolonged or not performed at all.

  Therefore, there is a demand for a technique for reducing inconveniences in various processes caused by the deviation between the position of the joining / leaving node and the extension direction of the joining / leaving link read from the road information and the travel locus in the actual joining / leaving travel. .

  The characteristic configuration of the road node position management system according to the present invention is a vehicle position information acquisition unit that acquires vehicle position information that represents the current position of a vehicle, and road information that represents a road by a connection relationship of a plurality of links and nodes. Information on driving control processing that may be executed within a predetermined section after passing through a junction / exit node as an intersection of a junction / exit link and a main line link in the road information acquisition unit, the junction Based on the vehicle driving condition acquisition unit that acquires a vehicle driving condition including at least one of the travel history of the vehicle at the leaving node and the geometric characteristic of the joining / leaving node, and the acquired vehicle driving condition, A first correction process for correcting the junction / exit node to a position suitable for the route guidance process of the vehicle, and a position suitable for the map matching process of the current position; A second determination process that corrects the flow / exit node, and a selection determination unit that selects which one to execute, and the position of the merge / exit node by the selected first correction process or the second correction process. And a node position correction unit for correction.

  The subject of the present invention is to correct the position of the joining / leaving node included in the road information to an appropriate position according to the vehicle driving conditions. At that time, there are node positions suitable for vehicle route guidance processing and node positions suitable for map matching processing as correction positions, and either correction node position is selected according to the contents of vehicle driving conditions at the junction / exit nodes. Is done. Such vehicle driving conditions include information on driving control processing that may be executed within a predetermined section after passing through the joining / leaving node, the travel history of the vehicle at the joining / leaving node, and the joining / leaving At least one of the geometric properties of the node is included. Based on these vehicle driving conditions, if it is determined that the priority of the route guidance process is high, it is corrected to a node position suitable for the route guidance process, and if it is determined that the priority of the map matching process is high, the map matching process Is corrected to a node position suitable for. This reduces the inconvenience of route guidance processing and map matching processing due to the deviation of the position of the merge / exit node and the extension direction of the merge / exit link read from the road information and the travel locus in the actual merge / exit travel can do.

The route guidance process uses the merge / exit node as a reference point for processing control timing, and the map matching process is performed based on the shape of the main link and the merge / exit link that intersect at the merge / exit node. In addition, the vehicle travel trajectory when traveling in the connecting section between the merge / exit lane and the main lane is important. Therefore, it is convenient to set a node position suitable for the route guidance process and a node position suitable for the map matching process from the actual vehicle travel locus. The transition point between the merging / leaving lane and the main lane and the merging / leaving angle at the time of the transition are the reference for such processing, and thus are particularly important information in the vehicle travel locus. Therefore, in one preferred embodiment of the present invention, the vehicle or other vehicle is based on the actual vehicle travel locus in the connection section between the junction / exit lane of the road corresponding to the junction / exit node and the main lane. Transition information for acquiring information on the position of a transition point between the merge / exit lane and the main lane and information on a merge / exit angle at the time of transition between the merge / exit lane and the main lane In the first correction process, the node position correction unit corrects the joining / exiting node so as to coincide with the position of the transition point, and an intersection angle with the main line link is the joining / leaving node. The merging / leaving node is corrected to the position of the intersection of the virtual merging / leaving link and the main line link that match the exit angle.
The merge / exit angle here refers to the angle formed by the extension direction of the vehicle's travel trajectory with respect to the extension direction of the main lane or the main link at the time of transition between the merge / exit lane and the main lane. It is. For example, the inclination angle with respect to the main link of the vehicle travel locus at the position of the transition point where the vehicle has shifted to the lane is an example of the merge / exit angle, and the vehicle detected by the image recognition processing of the lane marking of the main lane The angle formed by the vehicle traveling direction and the lane marking of the main lane at the position of the transition point where the lane transition is performed is also an example.

  When the operation control process is executed within a predetermined section after passing through the joining / leaving node, the accuracy and speed of the map matching process after passing through the joining / leaving node is important. In addition, route guidance in advance is often unnecessary at a junction / exit node that has traveled many times. In addition, route guidance in advance is often unnecessary even when the shape of the joining / leaving node, that is, the road shape corresponding to the joining / leaving node is simple. From such a point of view, in one of the preferred embodiments of the present invention, the selection determination unit is configured to determine whether the selection determination unit has passed the merging / leaving node based on the vehicle driving condition acquired by the vehicle driving condition acquiring unit. When there is a possibility that the operation control process is executed within a predetermined section, when there is a travel history that has passed through the joining / leaving node in the past, and the geometric characteristics of the joining / leaving node are classified into simple shapes The second correction process is selected, and in the other cases, the first correction process is selected.

  As described above, according to the present invention, the actual vehicle after passing through the joining / leaving node based on the information of the operation control processing that may be executed within the predetermined section after passing through the joining / leaving node. The position of the joining / exiting node can be corrected to a position adapted to the travel locus. In order to make effective use of this feature, in one preferred embodiment of the present invention, the driving control process includes a vehicle control for controlling a running state of the vehicle and a guidance process associated with the vehicle control. It is configured. As a result, the vehicle control after passing through the joining / leaving node and the accompanying guidance processing can be performed with high reliability.

Furthermore, the present invention reduces inconveniences in various processes caused by the deviation between the position of the joining / leaving node and the extending direction of the joining / leaving link read from the road information and the travel locus in the actual joining / leaving travel. The road node position management method and road node position management program are also subject to rights. For example, such a road node position management method includes a step of obtaining vehicle position information representing a current position of a vehicle, a step of obtaining road information representing a road by a connection relation of a plurality of links and nodes, and the road information Information of driving control processing that may be executed within a predetermined section after passing through the junction / exit node as the intersection of the junction / exit link and the main link in the middle, the travel history of the vehicle at the junction / exit node A vehicle driving condition including at least one of the geometric characteristics of the merging / leaving node, and the merging at a position suitable for a route guidance process of the vehicle based on the acquired vehicle driving condition. A first correction process for correcting the exit node and a second correction for correcting the merge / exit node at a position suitable for the map matching process of the current position. Comprising a step of selecting whether to perform the management, any, and correcting the position of the merging and exit nodes by the selected first correction processing or the second correction processing.
In addition, such a road node position management program includes a function of acquiring vehicle position information indicating the current position of the vehicle, a function of acquiring road information indicating a road by a connection relation of a plurality of links and nodes, and the road information. Information of driving control processing that may be executed within a predetermined section after passing through the junction / exit node as the intersection of the junction / exit link and the main link in the middle, the travel history of the vehicle at the junction / exit node , A function for acquiring a vehicle driving condition including at least one of the geometric characteristics of the merging / leaving node, and the merging at a position suitable for route guidance processing of the vehicle based on the acquired vehicle driving condition A first correction process for correcting the exit node, and a second correction process for correcting the merge / exit node at a position suitable for the map matching process of the current position; A function of selecting whether to perform one, to perform the function of correcting the position of the merging and exit nodes by the selected first correction processing or the second correction processing in the computer. Naturally, such a road node position management method and a road node position management program can also obtain the effects described in the facility exit guidance system described above, and some additional techniques described as preferred embodiments thereof. Can also be incorporated.

It is explanatory drawing which has shown typically the learning process which acquires the information for node correction used with the road node position management system by this invention. It is explanatory drawing which has shown typically the learning node position calculation algorithm for route guidance utilized in the learning process by FIG. It is explanatory drawing which has shown typically the learning node position calculation algorithm for map matching utilized in the learning process by FIG. It is the schematic diagram which modeled an example of the road information handled with the road node position management system by this invention. It is explanatory drawing which has shown typically the basic principle of the road node position management system by this invention. It is a functional block diagram of the navigation device for vehicles concerning one embodiment of the present invention. It is a flowchart which shows an example of a joining / leaving node learning routine. -A chart. It is a flowchart which shows an example of a straddle detection routine. -A chart. It is a flowchart which shows an example of a joining / exit node position learning routine. -A chart. It is a flowchart which shows an example of a learning node position utilization process. It is explanatory drawing which has shown typically the learning process in another embodiment. It is explanatory drawing which has shown typically the road node position management using the information acquired by the learning process by FIG.

Before describing a specific embodiment of a road node position management system according to the present invention, its basic principle will be described with reference to FIGS. In this road node position management system, it is necessary to prepare a correction node position used for correcting the joining / exiting node in advance. FIG. 1 schematically shows an example of a process for generating such a correction node position. FIG. 2 schematically shows a route guidance learning node position calculation algorithm employed in the correction node position generation process of FIG. FIG. 3 schematically shows a map matching learning node position calculation algorithm employed in the correction node position generation process shown in FIG. FIG. 4 is a schematic diagram schematically showing an example of road information handled by the road node position management system according to the present invention. FIG. 5 schematically shows the basic principle of the road node position management system according to the present invention.
In this explanation of the basic principle, as an example of merging / leaving running between the main lane and the merging / leaving lane, exit traveling that branches from the main road such as a highway or main road to the exit lane through the introduction lane The flow of various information (data) handled by the road node position management system according to the present invention in this leaving traveling is illustrated in FIGS.

FIG. 4 schematically shows road information of the road region used in FIG. 1 and FIG. 5, and such road information is usually made into a database and in a form according to the specifications of the map database. Stored. Here, as an example, the road network layer m1, the road shape layer m2, and the road attribute layer m3 are divided into three layers and stored.
The road network layer m1 is a layer indicating connection information between roads. Specifically, information on a large number of nodes N having position information on a map expressed by latitude and longitude, and information on a number of links K constituting a route corresponding to a road by connecting the two nodes N, Is recorded. Each link K records information such as road type (type of highway, toll road, national road, prefectural road, etc.) and link length as link information. Note that the node N connected to the branching link K is called a branch node. However, since this branch node is a reference point for joining and leaving the vehicle, it is also called a joining / leaving node here. In addition, a link that is connected to a main link that is a link representing a main lane (main road) by a branch node is referred to as a merge link / exit link.

The road shape layer m2 is a layer that is stored in association with the road network layer m1 and indicates the shape of the road. Specifically, information on the shape interpolation point s that is arranged between two nodes N (on the link K) and represents the detailed shape of the link K, and at each shape interpolation point s that represents the detailed shape of the road. Information on road width is recorded.
The road attribute layer m3 is configured in association with the road network layer m1 and the road shape layer m2, and is a layer in which detailed information regarding the road is recorded. Information recorded in the road attribute layer m3 includes, for example, information related to branch nodes, lane information of each road, and the like. Here, the lane information includes information such as the number of lanes of each road, the lane width of each lane, and the lane length. The lane information also includes information such as the positional relationship and connection relationship (link angle, etc.) of each lane between a plurality of roads that are branched and connected at a branch node. Here, the road information is a general term for information stored in each of the layers m1 to m3, and means any information included in the information.

[Obtain learning node position]
First, the basic principle of a learning process for acquiring node correction information through actual traveling will be described with reference to FIGS. 1, 2, and 3. FIG.
FIG. 1 shows a merging / exit node (simply referred to as “exit node” in the following description of the basic principle) N2, a link connected thereto, and an exit travel route as an exit travel route for shifting from the main lane to the exit lane. A vehicle trajectory of a vehicle traveling on the road is illustrated. Further, in order to explain the leaving travel with time, a time point indicating the passage of time, t1 to t5, is set, and the situation at that point will be described below. In the drawing, the leaving node N2 is indicated by a black dot, and each link connected to the leaving node is indicated by a bold solid line.

(1) Time point: t1
At this time: the vehicle is still traveling on the main lane in the time zone indicated by t1. Time point: t1 is a time (time stamp) when the vehicle position: P1 is generated.
(2) Time point: t2
At this time: t2 is a time (time stamp) when the steering operation is performed to move to the exit lane from the main lane to the exit lane. At this time: vehicle position P2 at t2 is acquired. The steering operation is indicated by a change in the steering angle. At this time point: t2, if a steering angle: θ indicating a predetermined steering operation occurs, steering operation information including the steering angle: θ is generated. Further, as an event of the steering operation history, the vehicle position: P2 at the time point: t2 and the steering operation information: θ are associated. Steering operation represented by this steering operation information: θ is used as a trigger to start a vehicle travel locus acquisition process for determining the position of the transition point between the main lane and the exit lane in this exit travel. In this example, the vehicle travel locus acquisition process includes an image recognition process that is performed based on a road surface image captured by the in-vehicle camera. With the detection of the steering operation represented by this steering operation information: θ as a trigger, the image recognition processing of the white thick broken line as the area identification line drawn on the road surface between the main lane and the exit lane starts. In the image recognition process, the position of the transition point can be determined by detecting the crossing of the white thick broken line as the area identification line drawn on the road surface between the main lane and the exit lane. Therefore, in the description of this basic principle, the position of the transition point is the vehicle straddling position with respect to the white thick broken line.

(3) Time point: t3
At this time point: t3, the vehicle travels across the area identification line drawn in white on the road surface by a white thick broken line in this embodiment. In the image recognition process for the road surface image taken by the in-vehicle camera, the area identification line is recognized, and the straddle recognition information X indicating this is issued. At this time: t3 is the start timing, and the following acquisition process of learning node positions that are candidates for corrected node positions starts.

(3-1)
Crossing recognition information: When X is issued: Vehicle position: P3 acquired at t3 is regarded as the position of the transition point (crossing travel position): Px. Based on this transition point position (crossing travel position): Px and the vehicle travel locus at this position: Px, a route guidance learning node position for performing node position correction suitable for route guidance processing (this example) Then, this is called a point matching position) and a map matching learning node position (in this example, this is called an angle matching position) for performing node position correction suitable for the map matching processing is obtained.

(A) Route guidance learning node position (point coincidence position) calculation algorithm Transition point position: For learning separately from the basic leaving node N2 which is a node in the road information, with Px as the learning leaving position which is an input parameter The point coincidence position that is the position on the main link of the exit position is calculated. In this calculation algorithm (a), as shown in FIG. 2, a perpendicular is drawn from the learning exit position: Px to the main link, and the intersection of the perpendicular and the main link is set as a point coincidence position: Nx.

(B) Map Matching Learning Node Position (Angle Matching Position) Calculation Algorithm As shown in FIG. 3, the calculation of the angle matching position as the map matching learning node position is performed by the following steps as an example. It can be carried out.
(1) The vehicle travel locus (indicated by K in the figure) is obtained at least near the transition point from the point where the steering operation is first performed for this leaving travel: P2 to the transition point: Px (P3). . The vehicle travel locus can be acquired by image recognition processing of a captured image by an in-vehicle camera, vehicle position detection processing using an orientation sensor or a distance sensor, and the like. This vehicle travel locus is the first learning information for map matching.
(2) When the vehicle travel locus is acquired, an intersection angle (indicated by αx in the figure) formed by the vehicle travel locus and the main line link can be calculated. Conversely, the vehicle travel locus can be assumed at least approximately from the intersection angle and the position of the transition point. That is, the map matching learning node position (angle matching position) can be derived from the intersection angle, that is, the merging / leaving angle. Therefore, this joining / leaving angle is the second learning information for map matching.
(3) When the joining / leaving angle is obtained, as is apparent from FIG. 3, this joining / leaving angle passes through the exit first node Nb which is the first node on the exit link extending from the exit node N2. By hypothesizing a straight line with an inclination angle, an angle coincidence position (indicated by Nαx in the figure) that is the intersection of the virtual straight line and the main line link can be calculated. This virtual straight line corresponds to the virtual joining / leaving link in the present invention. Therefore, this angle coincidence position is the third map matching learning information. The link connecting the angle coincidence position and the leaving first node Nb is a corrected link of the original link K3, and has good coincidence with the actual traveling locus of the vehicle. Therefore, in this example, this angle coincidence position is set as a learning node position for map matching.

(4) Time point: t4
At this time point: at t4, the transition of the vehicle to the exit lane is completed, and the vehicle is traveling in the exit lane.
(5) Time point: t5
At this time point: t5, the vehicle moves to the exit lane, and the vehicle position is set to a predetermined position on the link set in the exit lane by map matching for the link set in the exit lane.

[Use of learning node position]
When a learning node position that is a candidate for correcting the position of the joining / leaving node obtained from the road information is prepared, the position of the joining / leaving node can be corrected using the learning node position during actual traveling. An example of the basic principle of this correction process will be described with reference to FIG.
If the most recent scheduled route determined by map matching includes a join / leave node, the route guidance node correction candidate (point match position) that is the learning node position and the map matching learning are included in the join / leave node. It is checked whether the node position (angle matching position) is recorded in association with it. At the same time, the vehicle driving conditions at that time (indicated by D in the figure, the subscript corresponds to the number of the corresponding joining / leaving node) are acquired. The vehicle driving conditions include information on driving control processing that may be executed within a predetermined section after passing through the joining / leaving node, the travel history of the vehicle at the joining / leaving node, and the shape of the joining / leaving node. Characteristics, etc. Each vehicle driving condition further includes several vehicle driving condition factors (indicated by d1, d2,... In the figure). Here, the driving control process includes various driving controls performed by the vehicle side to assist the driver's operation. For example, the shift control for selecting the gear position according to the road shape, the vehicle speed, etc., the road shape Brake control that decelerates to an appropriate vehicle speed according to road conditions, etc., information acquisition processing and communication processing for performing vehicle control such as shift control and brake control, and notification that prompts the driver to perform brake operation and shift operation Processing, etc. The vehicle driving condition factors that are the factors for executing these driving control processes include, for example, vehicle speed, current position, road shape (node and link shapes), current gear position, congestion degree, and road surface condition. Road conditions, etc. are included. It is preferable that the travel history includes information such as the past travel date and time and the number of travels of the joining / leaving node, and further includes information on the annual or monthly travel frequency. The shape characteristics of the joining / leaving node include various types of information indicating the road shape near the joining / leaving node. For example, the number, shape, and mutual position of branch links existing in the joining / leaving node and its vicinity. It includes the relationship, the length of the link connected to the junction / exit node, the length of the connection section between the main lane and the junction / exit lane, and the road width of the main lane and the junction / exit lane. For example, information that can be directly extracted from a sensor signal, a map database, various data tables, or the like is used as a vehicle driving condition factor, and the vehicle driving condition is obtained from these vehicle driving condition factor groups. When obtaining the vehicle operating conditions from the vehicle operating condition factor group, it is convenient to set a function (denoted by D () in the figure) like a determination table in advance. Based on one or more vehicle driving conditions obtained in this way, correction processing of the node position using the route guidance learning node position (point matching position corresponding to the position on the link of the transition point); Either the correction processing of the node position using the learning node position for map matching (angle matching position) is selected, and the position of the latest joining / leaving node is corrected. Also in this selection process, it is convenient to set a function (denoted by J () in the figure) such as a determination table that outputs the selection result with the vehicle operating condition as an input.

  In the above description, the calculation of the learning node position with respect to the leaving node using the leaving travel is taken as an example. However, the learning node position with respect to the joining node can be calculated using the same procedure using the joining traveling. Therefore, here, the exit node and the join node are regarded as substantially the same, and are treated as the exit / join node.

〔Example〕
FIG. 6 is a functional block diagram showing an example of a vehicle navigation apparatus that employs a road node position management system that operates based on the basic principle described above. In this road node position management system, the process for correcting the merge / exit node to a position suitable for the vehicle route guidance process is called the first correction process, and the merge / exit node is corrected to a position suitable for the map matching process. This is referred to as a second correction process. As the route guidance processing learning node position used in the first correction process, a point coincidence position corresponding to the position of the transition point is employed. An angle coincidence position is adopted as a map matching learning node position used in the second correction processing.

  This navigation apparatus includes a navigation electronic control unit (hereinafter simply referred to as a navigation ECU) 3 as a core element, a dead reckoning navigation unit 5, a GPS unit 6, an image processing unit 7, a vehicle state detection management unit 8, and an in-vehicle camera 11. , A monitor 12 with a touch panel 13, a speaker 14, and the like.

  Signals from the distance sensor 8a and the azimuth sensor 8b are input to the dead reckoning unit 5 via the vehicle state detection management unit 8. The distance sensor 8a and the direction sensor 8b send detection signals to the dead reckoning unit 5 via the vehicle state detection management unit 8. The dead reckoning navigation unit 5 calculates dead reckoning position coordinates based on the signals related to the movement distance and the signals relating to the azimuth, which are sent every moment, and sends them to the navigation ECU 3 as vehicle position information by dead reckoning.

  The GPS unit 6 includes a GPS measurement unit that receives GPS signals from GPS satellites. The GPS unit 6 analyzes the signal from the GPS satellite received by the GPS measurement unit, calculates the current position (latitude and longitude) of the vehicle, and sends it to the navigation ECU 3 as vehicle position information based on the GPS position coordinates.

The image processing unit 7 includes a captured image acquisition unit 7a and an identification line straddling detection unit 70.
The captured image acquisition unit 7a acquires a captured image output by the camera 11 and performs necessary preprocessing such as distortion correction and density correction. The camera 11 includes a lens optical system and an image pickup device, and is at least a section line of a road around the vehicle, for example, a roadway center line, a lane boundary line, or an area provided between a main lane and a merge / exit lane An identification line (in this example, a white thick broken line) is provided at a position where photographing is possible. As such a camera 11, for example, a back camera or the like that is standard or optional on the vehicle is preferably used. The captured image acquisition unit 7a captures captured images from the camera 11 at a predetermined time interval, for example, about 10 to 50 ms.

  The identification line straddling detection unit 70 starts to operate in response to a command from the navigation ECU 3, and detects that the vehicle has entered the exit lane across the area identification line from the main lane. In this embodiment, the identification line straddling detection unit 70 detects the vehicle identification line stride based on the recognition of the area identification line obtained through the image recognition processing of the captured image from the camera 11. For this purpose, the identification line crossing detection unit 70 includes an identification line extraction unit 71, an identification line image buffer 72, an identification line crossing determination unit 73, and a crossing angle detection unit 74. The identification line extraction unit 71 performs binarization processing, edge detection processing, and the like on the captured image captured from the captured image acquisition unit 7a, and indicates a partition line indicating the outline of the area identification line included in the captured image. Extract images. The identification line image buffer 72 temporarily stores the generated lane marking images in order over time. The identification line straddling determination unit 73 compares the lane line images stored in the identification line image buffer 72 over time, obtains a motion vector from the lane line image, for example, and finally the vehicle straddles the area identification line. Judge that. When traveling across the area identification line of the vehicle is detected, the identification line straddling detection unit 70 sends identification line straddling detection information to the navigation ECU 3. The stride angle detection unit 74 detects an angle between the vehicle traveling direction and the region identification line from the lane marking image when the discrimination line straddling determination unit 73 detects the travel of the vehicle over the region identification line. The angle is included in the travel locus information sent to the navigation ECU 3, and can be used as information on the merging / leaving angle in the present invention. In this embodiment, the identification line straddling detection unit 70 determines the vehicle travel locus in the road area between the merge / exit lane and the main lane from the lane marking images stored in the identification line image buffer 72 over time. It has a function of generating travel locus information including it and sending it to the navigation ECU 3.

  The navigation ECU 3 includes a map database 30, a vehicle position information acquisition unit 31, a road information acquisition unit 32, and a navigation processing unit 4 as basic navigation function units. The vehicle position information acquisition unit 31 reads the current position of the vehicle from the vehicle position information sent from the dead reckoning navigation unit 5 or the GPS unit 6. The road information acquisition unit 32 acquires road information including necessary map information from the map database 30 based on the current position of the vehicle read by the vehicle position information acquisition unit 31. The road information acquisition part 32 gives the acquired road information to the function part of other navigation ECU3. Further, the road information acquisition unit 32 acquires the map information of the area requested for execution of the navigation processing in the navigation processing unit 4 from the map database 30 and transfers it to the navigation processing unit 4. As schematically shown in FIG. 3, the map database 30 includes data in a format divided into layers such as a road network layer m1, a road shape layer m2, a road attribute layer m3, and data in a list format. Various road information is stored.

  The navigation processing unit 4 operates in accordance with various installed application programs for executing navigation functions such as vehicle position display, route search from a departure point to a destination, route guidance to a destination, and destination search. An arithmetic processing function unit is included. For example, the navigation processing unit 4 displays a map image included in the road information around the current vehicle position acquired by the road information acquisition unit 32 on the monitor 12 and, on the map image, based on the vehicle position information. A process of displaying the vehicle position mark (symbol) in an overlapping manner is performed. Furthermore, the navigation processing unit 4 uses the monitor 12 and / or the speaker 14 based on the guidance route from the departure point to the destination calculated by a known method and the vehicle position information, and the route including the branch guidance. Give guidance. Further, when the vehicle position sent from the vehicle position information acquisition unit 31 includes a measurement error or the like and deviates from the road, the navigation processing unit 4 sets the vehicle position on the road indicated on the road map. It also has a map matching function unit that performs correction. The vehicle position corrected through the map matching process is given to the vehicle position information acquisition unit 31.

  The navigation ECU 3 includes a communication interface 20, a display control unit 21, and a sound processing unit 22. The communication interface 20 connects other modules or ECUs connected via the in-vehicle LAN and the navigation ECU 3 so that data can be transmitted. The display control unit 21 controls the display of route guidance images and captured images on the monitor 12. The voice processing unit 22 generates a voice signal obtained by converting the route guidance information and the like into voice, and outputs the voice signal to the speaker 14.

The navigation ECU 3 further includes a vehicle driving condition acquisition unit 33 that also has a travel locus acquisition function, a transition information acquisition unit 34, a steering operation history management unit 35, and a merger in order to realize the road node position management system described above. A leaving node position learning unit 36, a selection determining unit 37, and a node position correcting unit 38 are provided, and the function is substantially realized by executing a computer program. The vehicle driving condition acquisition unit 33 is configured so that the current position acquired by the vehicle position information acquisition unit 31 is a junction / exit as an intersection of the merge / exit link and the main line link in the road information acquired by the road information acquisition unit 32. Vehicle driving conditions are acquired when approaching a node within a predetermined distance. As described above, this vehicle driving condition includes information on driving control processing that may be executed in a predetermined section after passing through the joining / leaving node, vehicle travel history at the joining / leaving node, and the joining / leaving At least one of the geometrical properties of the node.
Further, the travel trajectory acquisition function of the vehicle driving condition acquisition unit 33 is based on the travel trajectory information sent from the identification line crossing detection unit 70 of the image processing unit 7 and the merge / exit lanes and main lines belonging to the merge / exit node. The vehicle travel locus in the connection section with the lane is acquired. In addition to the traveling track information sent from the identification line straddling detection unit 70, signals from the distance sensor 8a and the azimuth sensor 8b are received as traveling track information, and the vehicle traveling track is acquired from the traveling track information. Is possible.

  The transition information acquisition unit 34 determines whether the transition between the merge / exit lane and the main lane is based on the actual vehicle travel trajectory of the vehicle in the connection section between the merge / exit lane of the road corresponding to the merge / exit node and the main lane. Information on the position of the transition point and information on the merge / exit angle at the time of transition between the merge / exit lane and the main lane are acquired. Therefore, the transition information acquisition unit 34 includes a merging / leaving position acquiring unit 34a and a merging / leaving angle acquiring unit 34b.

  In this embodiment, the junction / exit position acquisition unit 34a calculates the transition point between the junction / exit lane and the main lane calculated based on the stored vehicle travel locus and the identification line straddling detection information. The position is acquired as the learning joining / exiting position. The merge / leave angle acquisition unit 34b calculates a merge / leave angle at the time of transition between the merge / leave lane and the main lane based on the stored vehicle travel locus. As the merging / leaving angle, either the angle of the traveling direction of the vehicle with respect to the main lane or the average inclination angle of the vehicle traveling locus with respect to the main lane can be used as the learning merging / leaving angle. That is, first, the vehicle travel locus based on the image recognition of the area identification line provided between the main lane and the merge / exit lane is acquired by the travel locus acquisition function of the vehicle driving condition acquisition unit 33. Next, based on the acquired vehicle travel locus, the merging / leaving position acquisition unit 34a acquires a point where the vehicle crosses the area identification line as a learning merging / leaving position, that is, a transition point, and acquires a merging / leaving angle. The unit 34b acquires the angle between the traveling direction of the vehicle and the area identification line when straddling the area identification line as the learning merging / leaving angle, that is, the intersection angle between the merging / leaving link and the main line link.

  The steering operation history management unit 35 performs steering at a predetermined timing, for example, when a merging / leaving node as an intersection of the merging link / leaving link and the main line link is present in the traveling front as a node where the vehicle merges or leaves. The recording of the operation history is started, and it is possible to grasp the point or point at which the steering operation is performed in order to join or leave the vehicle.

The merging / leaving node position learning unit 36 obtains road information based on the merging / leaving learning position acquired by the merging / leaving position acquiring unit 34a and the merging / leaving learning angle acquired by the merging / leaving angle acquiring unit 34b. In addition to the merging / leaving nodes recorded inside, the point of coincidence position that is the position of the learning merging / leaving position on the main link, and the intersection angle between the merging / leaving link and the main link are the learning merging / leaving angle An angle coincidence position which is a position coincident with is calculated. Since the method for calculating the point coincidence position and the learning merging / leaving angle has been described in detail with reference to FIGS. 2 and 3, the description thereof is omitted here.
In this embodiment, the joining / leaving node position learning unit 36 also performs execution condition control of processing by the joining / leaving position acquisition unit 34a and the joining / leaving angle acquisition unit 34b. First, the merge / exit node position learning unit 36 includes a merge / exit node scheduled to travel from the confluence lane to the main lane or from the main lane to the exit lane in the extracted planned travel route. Make sure. When the vehicle enters within a predetermined distance from the confirmed joining / leaving node, the image processing unit 7 is requested to detect the identification line straddling. As a result, the identification line crossing detection unit 70 of the image processing unit 7 operates and sends the travel locus information to the vehicle driving condition acquisition unit 33. Using the vehicle travel locus generated by the vehicle driving condition acquisition unit 33, the position of the transition point is acquired by the merging / leaving position acquiring unit 34a, and the merging / leaving angle acquiring unit 34b acquires the merging / leaving angle. . The learning merging / leaving position and the learning merging / leaving angle are calculated from the acquired transition point position and merging / leaving angle under the control management of the merging / leaving node position learning unit 36. The point matching position obtained as described above based on the calculated learning merging / leaving position is recorded as a route guidance learning node position that is a node correction candidate suitable for the route guidance process, and is calculated. The angle matching position obtained as described above based on the exit angle is recorded as a map matching learning node position that is a node correction candidate suitable for the map matching process.

  Based on the vehicle driving conditions acquired by the vehicle driving condition acquisition unit 33, the selection determining unit 37 corrects the joining / leaving node to a position suitable for the route guidance processing of the vehicle, and a map of the current position It is selected which of the second correction processing for correcting the joining / leaving node at a position suitable for the matching processing is executed. More specifically, when there is a possibility that the driving control process is executed within a predetermined section after passing through the joining / leaving node based on the acquired vehicle driving conditions, the joining / leaving node has been passed in the past. When there is a travel history, and when the geometric characteristics of the merge / exit node are classified into simple shapes, the second correction process is selected to prioritize the map matching process, and in other cases, the route guidance process The first correction process is selected to give priority to the above. Further, the operation control processing to be executed includes vehicle control for controlling the running state of the vehicle and guidance processing associated with the vehicle control. The vehicle control includes, for example, brake control, accelerator control, shift control, and the like. The guidance process accompanying the vehicle control includes, for example, guidance (notification) of the execution state of these vehicle controls, guidance (notification) for requesting the vehicle operation for the driver, and the like. Furthermore, the vehicle control includes communication for acquiring vehicle control information, which is a process associated with the vehicle control.

The selection between the first correction process (node correction process suitable for route guidance) and the second correction process (node correction process suitable for map matching) based on the vehicle driving conditions will be described more specifically.
As described above, the vehicle operation condition referred to when the selection determination unit 37 selects the correction process includes the first vehicle operation condition: operation control that may be executed within a predetermined section after passing through the merge / exit node. It includes at least one of processing information, second vehicle driving condition: vehicle travel history at the joining / leaving node, and third vehicle driving condition: geometric characteristic of the joining / leaving node. Based on these vehicle driving conditions, the selection determining unit 37 selects the first correction process to prioritize the route guidance process in a situation where it is highly necessary to perform route guidance for the driver, and the current position of the vehicle is accurately determined. In a situation where there is a high need for identification, the second correction process is selected to give priority to the map matching process. As described above, the driving control process includes various driving controls such as a shift control and a brake control performed by the vehicle side to assist the driver's operation. Such driving control on the vehicle side is often performed based on the current position of the vehicle on the road. Therefore, when there is a possibility that the operation control process is executed within a predetermined section after passing through the junction / exit node, the map matching process is prioritized in order to enable the appropriate execution of the operation control. It is desirable to select two correction processes. On the other hand, when there is no possibility that such a driving control process is executed or when the possibility is low, the route from the viewpoint of the convenience of the driver unless there is a need to perform another map matching process. It is desirable to select the first correction process by giving priority to the guidance process. Further, the necessity of route guidance for the joining / leaving node also varies depending on the driving experience of the joining / leaving node by the driver and the degree of complexity of the road shape branched at the joining / leaving node. That is, when the driver has never traveled the junction / exit node in the past, or when the shape of the branching road is complicated and there is a high possibility that the route is wrong, the route guidance process is given priority. It is desirable to select a correction process. On the other hand, when the driver is driving the merging / exiting node many times, or when the shape of the branching road is simple and there is a low possibility that the route will be wrong even without performing route guidance, the route guidance Therefore, the second correction process can be selected with priority given to the map matching process. The selection determination unit 37 performs a process of selecting an appropriate one of the first correction process and the second correction process in consideration of these vehicle driving conditions.

Therefore, in the present embodiment, as an example, the selection determination unit 37 performs the following determinations (1) to (3) with respect to the first to third vehicle operating conditions.
(1) Regarding the first vehicle driving condition, is there a possibility that the driving control process may be executed within a predetermined section after passing through the joining / leaving node, for example, within 200 m after passing through the joining / leaving node? Determine if there is any. Here, the possibility that the driving control process is executed is based on the vehicle speed, the current shift speed, the link shape within the predetermined section after passing through the merge / exit node, the road condition such as the degree of congestion and the road surface condition, etc. Determined. For example, when a curved road exists after passing through a merge / exit node, or when there is a traffic jam, there is a possibility that an operation control process such as brake control or shift down control is executed. As a result of this determination, the selection determination unit 37 selects the second correction process when the operation control process is likely to be executed, and selects the first correction process when the operation control process is not likely to be executed. To do.
(2) With respect to the second vehicle operating condition, it is determined whether or not there is a travel history that has passed through the joining / leaving node within a past predetermined period starting from the present, for example, within the past year. As a result of this determination, the selection determination unit 37 selects the second correction process when there is a travel history, and selects the first correction process when there is no travel history.
(3) With respect to the third vehicle driving condition, based on various information indicating the road shape near the merge / exit node, for example, the number and shape of the links connected to the merge / exit node and the mutual positional relationship, A determination is made to classify the geometric characteristics of the leaving node into a plurality of stages according to the complexity of the shape. Here, various types of information representing the road shape near the junction / exit node are acquired from the map database 30. Here, the selection determination unit 37 classifies the shape characteristics of the joining / leaving node into two types, a simple shape and a complex shape. As a result of this determination, the selection determination unit 37 selects the second correction process when the simple shape is classified, and selects the first correction process when the simple shape is classified.

  Then, the selection determination unit 37 weights and adds the determination results (1) to (3), and selects either the first correction process or the second correction process based on the result. At this time, since the execution of the operation control process such as the shift control and the brake control is highly important, it is preferable that the weight of the determination in (1) is larger than those in the other determinations (2) and (3). In addition, it is suitable also as a structure which performs selection by the selection determination part 37 based only on any one of said (1)-(3), or only two determination results. In addition to the first to third vehicle driving conditions, vehicle driving conditions that affect the necessity of route guidance processing and map matching processing, such as weather and ambient brightness, may be considered. Is preferred.

  The node position correction unit 38 corrects the position of the joining / leaving node by the first correction process or the second correction process selected by the selection determination unit 37. At that time, in the first correction process, the merge / exit node is corrected so as to coincide with the position of the transition point acquired by the transition information acquisition unit 34, and in the second correction process, the merge / exit link and the main line link are corrected. The merge / leave node is corrected to a position where the intersection angle matches the merge / leave angle acquired by the transition information acquisition unit 34. More specifically, in the first correction process, the position of the joining / leaving node is corrected to the point coincidence position as the route guidance learning node position, and in the second correction process, the position of the joining / leaving node is corrected to the map matching learning node. It corrects to the angle coincidence position as the position.

A flow of control for acquiring a learning node position as a node correction candidate for correcting a joining / leaving node in the road node position management system configured as described above will be described with reference to a flowchart of FIG.
When a guide route to the destination input through the touch panel 13 is calculated and travel is started, a joining / exit node learning routine is performed for the latest planned travel route sequentially taken from the guide route along with the travel. Done. Therefore, first, the road information acquisition unit 32 takes out the latest planned travel route (# 01). Whether the merge / exit node position learning unit 36 includes the merge / exit node scheduled to travel from the confluence lane to the main lane or from the main lane to the exit lane in the extracted planned travel route Is checked (# 02). If such a joining / leaving node is not included (# 02 No branch), it waits for the next latest travel planned route to be taken out. If such a joining / leaving node is included (# 02 Yes branch), the joining / leaving node position learning unit 36 further checks whether the joining / leaving node exists within a predetermined distance ( # 03). The vehicle waits until the vehicle enters within a predetermined distance from the joining / leaving node, and when the vehicle enters within the predetermined distance from the joining / leaving node (# 03 Yes branch), the joining / leaving node position learning unit 36 sends the image processing unit 7 The detection of the identification line crossing is requested (# 04). The image processing unit 7 receives the request for detection of the identification line crossing and executes a crossing detection routine (# 05).

When the straddle detection routine shown in FIG. 8 is executed, the captured image acquisition unit 7a sequentially captures the captured images of the in-vehicle camera 11, performs necessary preprocessing, and develops them in the memory (# 51). The identification line straddling detection unit 70 performs the following straddle detection processing on the captured image developed in the memory. First, the identification line extraction unit 71 extracts an area identification line that is a thick broken line between the main lane and the merge / exit lane using an edge detection filter or the like (# 52). When the area identification line is not extracted (# 53 No branch), the process proceeds to the next photographed image. When the area identification line is extracted (Yes in # 53), the extracted area identification line is marked and the identification line image is temporarily stored in the identification line image buffer 72 (# 54). The identification line straddling determination unit 73 determines the timing at which the vehicle straddles the area identification line from the identification line images stored in the identification line image buffer 72 in the order of time (# 55). If it is not determined that the vehicle crosses the area identification line (# 56 No branch), the elapsed time of the crossing detection process is checked (# 57). If the elapsed time is within the predetermined time (# 57 No branch), the crossing detection process is further continued. When the elapsed time exceeds the predetermined time (# 57 Yes branch), the identification line straddling detection unit 70 sends straddle detection information whose content is “non-detection” to the navigation ECU 3 (# 58), and ends this routine. When it is determined in step # 55 that the vehicle has crossed the area identification line (Yes in # 56), the identification line crossing detection unit 70 sends the crossing detection information including “detection” to the navigation ECU 3 (# 59). End the routine.
The identification line straddling detection unit 70 stores the identification line images in the identification line image buffer 72 in the order of time during the execution of the straddle detection routine and until the vehicle travels a predetermined distance after the straddle detection. Then, travel locus information including the vehicle travel locus is generated from the identification line image. Then, the identification line straddling detection unit 70 sends the generated travel locus information to the vehicle driving condition acquisition unit 33.

  When the straddle detection routine ends, the joining / leaving node position learning unit 36 confirms straddle detection from the straddle detection information sent from the image processing unit 7 (# 6). If it is confirmed that the identification line crossing is not detected (# 6 No branch), the process of step # 7 is jumped and the process proceeds to step # 8. When the identification line crossing is confirmed (# 6 Yes branch), the joining / leaving node position learning unit 36 detects the time (time stamp) when the identification line crossing is detected, the vehicle position information at that time, Using the information of the joining / leaving node that is the target of the leaving node learning process as an input parameter, the travel locus necessary for the processing stored in the vehicle operating condition obtaining unit 33 is read, and the joining / leaving position obtaining unit 34a is read out. And the merging / leaving angle acquisition unit 34b. Thus, the control shifts to a join / leave node position learning routine executed by the join / leave position acquisition unit 34a and the join / leave angle acquisition unit 34b under the control of the join / leave node position learning unit 36 ( # 7).

This joining / leaving node position learning routine is shown in FIG. 9, and explanatory diagrams schematically showing the explanation are shown in FIG. 2 and FIG.
First, the algorithm (a) described with reference to FIG. 2 is used for the travel locus information acquired by the vehicle operating condition acquisition unit 33, specifically, the vehicle travel locus including the transition point position by the joining / exiting position acquisition unit 34a. Is applied to calculate the learning joining / leaving position (# 71). A point coincidence position is calculated from the calculated learning joining / exiting position (# 72), and the calculated point coincidence position is recorded as a route guidance learning node position which becomes a route guidance node correction candidate (# 73).

  Next, the algorithm (b) described with reference to FIG. 3 is applied to the travel locus information acquired by the vehicle operating condition acquisition unit 33, specifically, the vehicle travel locus including the transition point position by the joining / exiting angle obtaining unit 34b. ) Is applied to calculate the learning merging / leaving angle (# 76). An angle coincidence position is calculated from the calculated learning merging / leaving angle (# 77), and the calculated angle coincidence position is recorded as a map matching learning node position to be a map matching node correction candidate (# 78).

When the navigation ECU 3 returns from the joining / leaving node position learning routine, it is checked whether or not the termination of the navigation processing is instructed (# 8), and unless the termination is instructed (# 8 No branch), this joining / leaving node When the learning routine is repeated and the termination is instructed (# 8 Yes branch), the navigation process is terminated.
The navigation process ends.

  The point coincidence position as the route guidance learning node position and the angle coincidence position as the map matching learning node position, which are generated and recorded through the merging / leaving node position learning routine described above, are selected by the selection determining unit 37. Is used to correct the corresponding merge / exit node.

Next, an example of the merging / leaving node correction process will be described with reference to the flowchart of FIG. In this example, the joining / leaving node is corrected to the point coincidence position or the angle coincidence position based on the vehicle operation condition acquired at that time. This junction / exit node correction process is substantially performed by the vehicle operating condition acquisition unit 33, the selection determination unit 37, and the node position correction unit 38.
First, the vehicle position information acquisition unit 31 takes in the vehicle position (# 80), and the road information acquisition unit 32 takes in the latest node information on the road route scheduled to travel (# 81). It is checked whether or not the node read from the fetched node information is a joining / leaving node (# 82). If it is not a joining / exiting node (# 82 No branch), this processing routine is terminated because it is not a processing target. If the read node is a joining / leaving node (# 82 Yes branch), it is further checked whether the joining / leaving node is unprocessed in this processing routine (# 83). If the process has been completed (# 83 No branch), the process returns to step # 80 to continue this process from the beginning. If not processed (# 83 Yes branch), the vehicle driving condition acquisition unit 33 acquires the vehicle driving condition factor (# 84). Further, the vehicle driving condition acquisition unit 33 determines the vehicle driving condition from the acquired vehicle driving condition factor. The vehicle driving conditions treated here are information on driving control processing that may be executed within a predetermined section after passing through the joining / leaving node, traveling history of the vehicle at the joining / leaving node, joining / leaving node The one or more vehicle operating conditions are determined and given to the selection determination unit 37. Based on the given vehicle driving conditions, the selection determining unit 37 corrects the joining / leaving node to a position suitable for the vehicle route guidance process, and the joining / leaving node to a position suitable for the map matching process. Which one of the second correction processes to correct is performed is selected (# 86). The vehicle driving condition determination process and the correction process selection process are described with reference to FIG.

  When the first correction process is selected in step # 86, it is checked whether or not the route guidance learning node position is recorded in the joining / leaving node to be processed (# 87). If the route learning node position is recorded in this joining / leaving node (# 87 Yes branch), the difference between this joining / leaving node and the route guidance learning node position assigned to this joining / leaving node ( It is checked whether or not (positional difference) exceeds a preset position threshold value (# 88). If the position difference exceeds the position threshold value (# 88 Yes branch), the merging / leaving node to be processed is rewritten and corrected with the route guidance learning node position recorded in association with the merging / leaving node. (# 89). That is, correction is performed so that the joining / exiting node matches the point matching position. If the position difference does not exceed the position threshold value (# 86 No branch), the correction process is terminated without correcting the joining / exiting node this time. If the route guidance learning node position is not recorded in this joining / leaving node in step # 87 (# 87 No branch), this correction process is terminated as it is.

  When the second correction process is selected in step # 86, it is checked whether or not the map matching learning node position is recorded in the joining / leaving node to be processed (# 90). If the map matching learning node position is recorded in the joining / leaving node (# 90 Yes branch), the intersection angle is checked (# 91). In this intersection angle check, the merging calculated based on the intersection angle between the merging / leaving link and the main link intersecting at the merging / leaving node and the learning node position for map matching assigned to the merging / leaving node. Check whether the difference (angle difference) between the exit link and the main line crossing angle exceeds a preset angle threshold. If the angle difference exceeds the angle threshold value (# 91 Yes branch), the merge / leave node to be processed is rewritten and corrected with the map matching learning node position recorded in association with the merge / leave node. (# 92) That is, correction is performed so that the joining / leaving node matches the angle matching position. If the angle difference does not exceed the angle threshold value (# 91 No branch), this correction process is terminated without correcting the merge / exit node this time. Further, if the route guidance learning node position is not assigned to this joining / leaving node in step # 90 (# 90 No branch), this correction processing is terminated as it is.

[Another embodiment]
In the previous embodiment, the two types of node correction candidates for correcting the joining / leaving node are acquired by learning through actual driving of the vehicle, and the selection of the node correction candidate to be used is acquired at the time of selection. The vehicle driving conditions were the criterion. In another embodiment described below, a vehicle driving condition is also learned and stored when traveling through the joining / leaving node, and is used as a vehicle driving condition when selecting a node correction candidate to be used. The basic principle at the time of learning of such another embodiment is shown in FIG. 11, and the basic principle at the time of use is shown in FIG.

  Furthermore, in the basic principle shown in FIGS. 11 and 12, the angle matching position is used as learning information for determining a node correction candidate used when correcting the joining / leaving node to a position suitable for the map matching process. In addition, the crossing angle (confluence / exit angle: indicated by αx in the figure) and the traveling locus (indicated by K in the figure) are recorded and can be used. This is because the angle coincidence position can be derived from the travel locus and the intersection angle, as is clear from the explanation using FIG.

  The basic principle of learning is shown in FIG. 11, which is similar to FIG. The most different point from the previous example is that a plurality of vehicle driving condition factors (indicated by d1 to d5 in the figure) are sequentially detected during this learning process. One or more vehicle driving conditions at this merging / leaving node based on a predetermined decision rule (indicated by J in the figure) from the detected vehicle driving condition factors (indicated by simply D2 in the figure) Is derived. The derived vehicle driving conditions are stored in the vehicle driving condition database in association with the joining / leaving node. The vehicle driving condition factors include vehicle travel speed data, vehicle operation data (shift operation, brake operation, etc.), road conditions (road width, traffic congestion etc.), weather conditions, vehicle map coordinate position, and the like. As vehicle driving conditions derived from such vehicle driving condition factors, information on driving control processing executed in a predetermined section after passing through this joining / leaving node, traveling history of the vehicle at this joining / leaving node The shape characteristic of the joining / leaving node, the driving operation information by the driver in the vicinity of the joining / leaving node, and the like. Therefore, in this alternative embodiment, each time the vehicle travels on the same junction / exit node, the point coincidence position as the route guidance node correction candidate and the angle coincidence position or merge / exit angle as the map matching node correction candidate Since the travel locus is recorded and the vehicle driving conditions acquired at that time are accumulated in the vehicle driving condition database, the accuracy can be improved through averaging of learning data and detailed sorting.

  The basic principle for use in this alternative embodiment is shown in FIG. 12, which is similar to FIG. The difference from the usage form based on FIG. 5 is that not only the current vehicle operating conditions at the joining / exiting node are acquired when attempting to travel, but also the past vehicle operating conditions at the time of traveling at the joining / exiting node It is obtained from the condition database. Then, based on the past and current vehicle driving conditions, a method for correcting the junction / exit node is selected based on a predetermined decision rule (indicated by L in the figure). In other words, in consideration of past vehicle driving conditions, the current vehicle driving conditions determine whether route guidance processing or map matching processing should be prioritized at this merging / leaving node, and are suitable for the priority processing. A correction method for the joining / leaving node is selected. When the route guidance process has priority, the joining / leaving node is corrected to the point matching position, and when the map matching process has priority, the joining / leaving node is corrected to the angle matching position. In the correction process to the angle coincidence position, if the recorded learning information is the merging / exiting angle: αx, the angle coincidence position: Nαx is derived from αx, and the recorded learning information is the travel locus: K. Then, αx is derived from K, and the angle coincidence position: Nαx is derived from αx.

[Other Embodiments]
(1) In the above-described embodiment, a configuration is adopted in which learning for calculating a node correction candidate and use of the node correction candidate are performed in the same vehicle. However, the learning for calculating the node correction candidate and the use of the node correction candidate may be performed in different vehicles. For example, learning for calculating node correction candidates can be performed by a probe car, that is, a plurality of vehicles including the own vehicle or a vehicle that specializes in the learning process, and the acquired data can be recorded in the database of the management center. . A general vehicle using the node correction candidate can use the learning node position as the node correction candidate by downloading the data recorded in the database of the management center.

(2) In the embodiment described above, associating the learning node position with the road information means that the learning node position is associated with the corresponding joining / leaving node included in the road information. For example, the link may be associated with a link. It may be associated with a link included in other road information, or a specific feature or symbol.

(3) In the above-described embodiment, the node correction candidate is the learning node position acquired through the learning process, but the node correction candidate derived without the learning process may be used. For example, a table or the like constructed by associating various vehicle driving conditions with the correction amount of the node position can be used. In this case, the first correction process or the second correction process is selected according to the acquired vehicle driving condition, and the node position is set with the correction amount read from the table based on the vehicle driving condition in each correction process. It is possible to employ a configuration for correcting.

  The road node position management system according to the present invention can be applied not only to car navigation but also to a system that executes various controls based on nodes included in road information.

3: Navigation ECU
31: Vehicle position information acquisition unit 32: Road information acquisition unit 33: Vehicle driving condition acquisition unit 34: Transition information acquisition unit 34a: Junction / exit position acquisition unit 34b: Junction / exit angle acquisition unit 35: Steering operation history management unit 36 : Joining / leaving node position learning unit 37: Selection determining unit 38: Node position correcting unit 4: Navigation processing unit 5: Dead reckoning unit 6: GPS unit 7: Image processing unit 7a: Captured image acquisition unit 70: Detection of crossing identification line Unit 71: Identification line extraction unit 72: Identification line image buffer 73: Identification line crossing determination unit 74: Crossing angle detection unit 8: Vehicle state detection management unit

Claims (6)

A vehicle position information acquisition unit for acquiring vehicle position information representing the current position of the vehicle;
A road information acquisition unit that acquires road information representing a road by a connection relationship of a plurality of links and nodes;
Information on driving control processing that may be executed within a predetermined section after passing through the junction / exit node as the intersection of the junction / exit link and the main link in the road information, the vehicle at the junction / exit node Vehicle driving condition acquisition unit for acquiring a vehicle driving condition including at least one of the travel history of the vehicle, and the geometric characteristic of the junction / exit node,
Based on the acquired vehicle driving conditions, a first correction process for correcting the joining / leaving node to a position suitable for the route guidance process of the vehicle, and the joining to a position suitable for the map matching process of the current position A second determination process for correcting the exit node, and a selection determination unit that selects which one to execute;
A node position correction unit that corrects the position of the joining / leaving node by the selected first correction process or the second correction process;
A road node position management system comprising: Based on the actual vehicle travel trajectory of the vehicle or other vehicle in the connecting section between the merging / leaving lane and the main lane of the road corresponding to the merging / leaving node, between the merging / leaving lane and the main lane It further includes a transition information acquisition unit that acquires information on the position of the transition point, and information on the merge / exit angle at the time of transition between the merge / exit lane and the main lane,
In the first correction process, the node position correction unit corrects the merging / leaving node to coincide with the position of the transition point, and in the second correction process, the intersection angle with the main line link is the merging point. 2. The road node position management system according to claim 1, wherein the junction / exit node is corrected to a position of an intersection of a virtual junction / exit link that matches the exit angle and the main line link.   When the selection determination unit is likely to execute the operation control process within a predetermined section after passing through the junction / exit node based on the vehicle operation condition acquired by the vehicle operation condition acquisition unit, When there is a travel history that has passed through the joining / leaving node in the past, and when the geometric characteristics of the joining / leaving node are classified into simple shapes, the second correction process is selected, and in other cases The road node position management system according to claim 1 or 2, wherein the first correction process is selected.   The road node position management system according to any one of claims 1 to 3, wherein the driving control process includes a vehicle control for controlling a traveling state of the vehicle and a guidance process accompanying the vehicle control. Obtaining vehicle position information representing the current position of the vehicle;
Acquiring road information representing a road by a connection relationship of a plurality of links and nodes;
Information on driving control processing that may be executed within a predetermined section after passing through the junction / exit node as the intersection of the junction / exit link and the main link in the road information, the vehicle at the junction / exit node Obtaining a vehicle driving condition including at least one of the following driving history and the geometric characteristic of the joining / leaving node;
Based on the acquired vehicle driving conditions, a first correction process for correcting the joining / leaving node to a position suitable for the route guidance process of the vehicle, and the joining to a position suitable for the map matching process of the current position Selecting a second correction process for correcting the exit node, and
Correcting the position of the joining / leaving node by the selected first correction process or the second correction process;
A road node position management method comprising: A function of acquiring vehicle position information representing the current position of the vehicle;
A function of acquiring road information representing a road by a connection relation of a plurality of links and nodes;
Information on driving control processing that may be executed within a predetermined section after passing through the junction / exit node as the intersection of the junction / exit link and the main link in the road information, the vehicle at the junction / exit node A vehicle driving condition including at least one of the following driving history and the geometric characteristics of the merge / exit node;
Based on the acquired vehicle driving conditions, a first correction process for correcting the joining / leaving node to a position suitable for the route guidance process of the vehicle, and the joining to a position suitable for the map matching process of the current position A function for selecting which of the second correction processing for correcting the leaving node,
A function of correcting the position of the joining / leaving node by the selected first correction process or the second correction process;
Road node position management program that causes a computer to execute.

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