JP2006133014A - Road state estimation device and road state estimation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To estimate the optimum road state in accordance with a traffic state. <P>SOLUTION: A section passage time recording part 71 records a passing time of each prescribed road section, and a road state estimation part 72 selects the passing time of each prescribed road section pertinent to traffic information from the recorded passing times, extracts a passing time corresponding to a traffic flow included in the traffic information from the selected passing time of each prescribed road section, and estimates the passing time of each prescribed road section from the extracted passing time. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a road situation estimation apparatus and a road situation estimation method that estimate a road situation by using only past passage times of predetermined road sections that match a speed range of a traffic flow.

  Conventionally, a route guidance device that guides a route from a departure point to a destination and an arrival time to the destination is known. According to such a route guidance device, the driver can reach the destination by driving according to the guidance of the route guidance device.

  By the way, some of such route guidance devices use traffic information such as VICS to judge the traffic congestion status of the route to the destination and reflect the judgment result in the route guidance. However, in the conventional route guidance devices, for example, in order to determine the traffic jam situation based only on the traffic jam distance, for example, the traffic jam distance is the same 300 m, but the transit time is also 5 minutes and 20 minutes, two different cases By determining that the traffic conditions are the same, it may not be possible to guide the optimum route according to the actual traffic conditions.

Against this background, recently, route guidance that records the time required for a vehicle to pass through a predetermined road section and performs optimum route guidance according to traffic conditions in consideration of the average passage time of the predetermined road section An apparatus has been proposed (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2003-4466

  However, the above conventional route guidance devices calculate the average value of all the recorded transit times, in order to calculate the average transit time of the predetermined road section, in addition to the transit time at the time of traffic jam, The transit time when there is no traffic jam is also used in the calculation, and the road condition cannot be estimated with high accuracy.

  The present invention has been made to solve the above-described problem, and provides a road condition estimation apparatus and a road condition estimation method capable of estimating a road condition with high accuracy.

  In order to solve the above-described problems, a road condition estimation apparatus and a road condition estimation method according to the present invention record a passing time for each predetermined road section, and for each predetermined road section corresponding to traffic information from the recorded passing time. The passage time corresponding to the traffic flow included in the traffic information is extracted from the passage time for each selected predetermined road section, and the passage time for each predetermined road section is calculated from the extracted passage time. presume.

  According to the road situation estimation apparatus and the road situation estimation method according to the present invention, only the passage time corresponding to the traffic flow included in the traffic information is extracted from the passage times recorded in the past, and the extracted passage time is used. Since the passage time for each predetermined road section is estimated, the road condition can be estimated with high accuracy.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Overall configuration of in-vehicle route guidance system]
First, with reference to FIG. 1, the structure of the vehicle-mounted route guidance apparatus which becomes the 1st Embodiment of this invention is demonstrated.

  As shown in FIG. 1, the in-vehicle route guidance device 1 according to the first embodiment of the present invention mainly includes a vehicle current position detection unit 2, a traffic information reception unit 3, a map database 4, and a section passage time. A database 5, a display device 6, and a control unit 7 that controls the vehicle-mounted route guidance device 1 including these units are provided.

[Details of each component]
The vehicle current position detector 2 detects the current position of the vehicle using a vehicle current position detector such as GPS (Global Positioning System). Then, the vehicle current position detection unit 2 inputs the detected information to the control unit 7.

  The traffic information receiving unit 3 functions as a traffic information acquisition unit according to the present invention, receives traffic information from a VICS (Vehicle Information and Communication System) or the like, and inputs the received information to the control unit 7 To do.

  The map database 4 includes a recording medium (for example, HD or DVD-ROM) for recording data necessary for guiding the route from the departure point to the destination set by the vehicle occupant, and a controller that reads information from the recording medium. 7 to an encoder for transmission to the network.

  On this recording medium, as necessary data, road data related to road connections, map screen data for displaying a map screen consisting of roads, buildings, parks, rivers, etc. on the display screen, vehicle position during traveling Map data composed of map matching data for identifying the image on the map screen is recorded.

  Each road included in the road data is divided into a plurality of road sections (hereinafter referred to as links), and each link is connected to an adjacent link by a node. The road data includes information on links (hereinafter abbreviated as link information), information on nodes (hereinafter abbreviated as node information), and information on connections between links (hereinafter abbreviated as link connection information). As the link information, a “link identification number” that is a unique number for identifying a link, a “link class” that indicates a road type such as an expressway, a toll road, a national road, a prefectural road, or a link map In the map database 4, “start point coordinates” and “end point coordinates” representing coordinates, “link length” representing the link length, “link cost” used in route guidance processing, and information relating to the link itself are recorded. On the other hand, as the node information, “node identification number”, which is a unique number of nodes connecting the links, is also recorded in the map database 4.

  The section passage time database 5 functions as a recording unit according to the present invention, and records a passage time for each predetermined road section generated by a database generation process described later. A specific configuration of the section passage time database 5 will be described in a database generation process described later.

  The display device 6 displays map information and route guidance information output from the control unit 7.

  The control unit 7 is configured by a known information processing device, and when an internal CPU (Central Processing Unit) executes a program, the section passage time calculation means, the section passage time selection means according to the present invention, It functions as a section passage time extraction unit and a section passage time estimation unit, and realizes the operations of the section passage time recording unit 71, the road condition estimation unit 72, the route calculation unit 73, and the presentation unit 74. The functions of the section passage time recording unit 71, the road condition estimation unit 72, the route calculation unit 73, and the presentation unit 74 will be described later.

  The vehicle-mounted route guidance device 1 having such a configuration performs optimum route guidance according to road conditions by executing the following database generation processing and route guidance processing. Hereinafter, the operation of the route guidance device 1 when executing the database generation processing and the route guidance processing will be described.

[Database creation processing]
First, the operation of the control unit 7 when generating the section passage time database 5 and the configuration of the section passage time database 5 generated by the database generation processing will be described with reference to the flowchart shown in FIG.

  The flowchart shown in FIG. 2 starts when the engine of the vehicle is started or the power of the vehicle-mounted route guidance apparatus is turned on, and the process proceeds to step S1.

  In step S <b> 1, the vehicle current position detection unit 2 acquires vehicle current position information and inputs it to the control unit 7.

  In step S2, the section passage time recording unit 71 acquires a link corresponding to the current position of the vehicle from the map database 4 based on the input current location information, and the time when the vehicle passes near the start point of the link. The time required to pass through the link is obtained by subtracting the time passed near the start point from the time passed near the end point from the time passed near the end point (hereinafter referred to as the transit time). (Abbreviation) is calculated. Then, the section passage time recording unit 71 classifies the calculated passage times for each day of the week and time zone and records them in the section passage time database 5. Here, the recording method in the section passage time database 5 will be specifically described with reference to FIG.

  In this embodiment, the passage time calculated by the section passage time recording unit 71 is recorded in the section passage time database 5 for each table divided into the link identification number, day of the week, and time zone. For convenience of description, it is assumed that there are p (p> 0) link identification numbers.

  Each table is divided into 48 sections from Monday to Sunday for each link identification number. In the example of FIG. 3, if the vehicle passes the link corresponding to the link identification number 1 between 8:00 and 8:30 on Monday, the passing time is the hatched portion of the section passing time database 5. Recorded in the section. The hatched section is specifically configured as shown in FIG. 4. For example, on Monday in the first week of August, the passing time of the link corresponding to the link identification information 1 is 20 seconds. Yes, the information indicating that the passing time was 68 seconds is recorded on Monday of the third week of August, which is the next driving time. In this section, accompanying information such as the passing vehicle speed is also recorded. Each section can record up to N pieces of transit time and accompanying information. When the N + 1st data is recorded, the oldest data is erased and recorded.

  In this way, the section passage time recording unit 71 always obtains the passage time information of the link on which the vehicle has traveled and records it in the section passage time database 5 even in a situation where traffic information is not obtained.

  In step S3, the control unit 7 determines whether or not the vehicle engine is stopped or the vehicle-mounted route guidance device is turned off. If the vehicle engine is stopped or the vehicle-mounted route guidance device is turned off, The database generation process ends. Otherwise, the process proceeds to step S1, and the database generation process is repeatedly executed.

[Route guidance setting process]
Next, the operation of the route guidance apparatus 1 when performing route guidance setting processing will be described with reference to the flowchart shown in FIG.

  In the process of step S11, the road condition estimation unit 72 determines whether the traffic information receiving unit 3 has received traffic information from VICS or the like. If the traffic information is received by the traffic information receiving unit 3, route setting is performed. The guidance process proceeds to step S12. On the other hand, when the traffic information receiving unit 3 has not received the traffic information, the route guidance setting process proceeds to the process of step S19. Here, the traffic information includes a traffic flow for each of a plurality of predetermined road sections and link and node information corresponding to each road section. Note that the number of links corresponding to a predetermined road section is not necessarily one.

  In the processing of steps S12 to S15, the road situation estimation unit 72 estimates the road situation for each road section based on the acquired traffic information. Hereinafter, it demonstrates in order.

  In the process of step S12, the road condition estimation unit 72 acquires the link information included in the traffic information and the table corresponding to the current day of the week from the section passage database 5, and proceeds to the next step S13.

  In the process of step S13, the road condition estimation unit 72 selects a section corresponding to the current time zone from the previously acquired table, and the past transit time for each road section included in the traffic information (hereinafter, Abbreviated as past passage time.) And proceeds to the next step S14.

  In the process of step S14, the road condition estimation unit 72 derives a conditional expression from the speed range of the traffic flow for each road section and the past passage time, and converts the conditional expression from the past passage times extracted in the process of step S13. The matching past passage time is acquired, and the process proceeds to the next step S15.

In this embodiment, the road condition estimation unit 72 classifies the traffic flow into three according to the speed and the traffic condition, as shown in the following formulas 1, 2, and 3, and traffic jams in each speed range, Allocate congestion and good road conditions.

And the road condition estimation part 72 converts the unit of the said Numerical formula 1, 2, 3 from speed to time by using Numerical formula 4 shown below, and traffic congestion as shown to the following Numerical formula 5, 6, 7 is shown. The passage time in each of the road conditions of congestion and smoothness is calculated as a conditional expression. In Equations 1, 2, and 3, V is the traffic flow speed, D _{vics in} Equation 4 is the link distance based on traffic information, S _max is the maximum speed in the traffic flow speed range, and S _min is the traffic flow. The minimum speed in the speed range, T, is the estimated vehicle transit time.

  In general, when setting the route, when considering the balance between the route length, which is the distance from the departure point to the arrival point, and the arrival time, selecting a road where chronic congestion occurs as a route is Not correct. Therefore, in the process of step S16, roads that can be passed in an appropriate time and roads that cannot be passed are classified as link costs according to the transit time, and the actual cost is calculated by referring to this link cost when performing route calculation. Route guidance considering road conditions is made possible.

  To give a specific example, in the conventional route setting, it was judged that “300m traffic jam due to stop waiting for traffic lights” and “300m traffic jam due to waiting for a level crossing without opening” were similar traffic jams. In some cases, optimal route setting could not be performed. Therefore, the present invention does not calculate the transit time based on the distance, but changes the current traffic situation from the recorded transit time of the predetermined road section based on the speed range of the traffic flow classified for each traffic situation. Since only the transit time that matches the speed range of the relevant traffic flow is extracted and the current transit time is estimated from the extracted transit time, it is possible to obtain a more accurate transit time according to the actual traffic situation. It is possible to set an appropriate route.

  In the process of step S17, the presentation unit 74 acquires map data around the vehicle from the map database 4, and creates map image data in consideration of road conditions. The created map image data is output to the display device 6 and proceeds to the next step S18. Specifically, as shown in FIG. 6, the presentation unit 74 displays arrows that are color-coded according to traffic conditions such as congestion and congestion on the map screen. As shown in FIG. 7, the presentation unit 74 may divide the road situation into four stages of heavy traffic jam, traffic jam, congestion, and smoothness, and display a more detailed road situation on the map screen.

  In the process of step S18, the display device 6 displays the map image data output from the presentation unit 74, and proceeds to the next step S19 after the display.

  In the process of step S19, the control unit 7 determines whether or not there is an instruction to perform route guidance calculation from the passenger. If there is an instruction, the route setting guidance process proceeds to step S20. On the other hand, if there is no instruction from the passenger to execute the route guidance calculation, the route guidance setting process proceeds to step S22.

  In step S20, the route calculation unit 73 calculates a route to the destination set using the map database 4, and proceeds to the next step S21.

  In the process of step S21, the presentation unit 74 reads map data including the route calculated from the map database 4, and the display device 6 displays the map data as a map screen, and proceeds to the next step S22.

  In the process of step S22, the control unit 7 determines whether or not the vehicle engine is stopped or the power of the in-vehicle route guidance device is turned off, and the vehicle engine is stopped or the power of the in-vehicle route guidance device is turned off. If there is, the route guidance setting process ends. If not, the process proceeds to step S11, and the route guidance setting process is repeatedly executed.

  As is apparent from the above description, according to the route guidance device 1 according to the first embodiment of the present invention, the section passage time recording unit 71 records the passage time for each predetermined road section, and the road condition estimation unit. 72 selects the passage time for each predetermined road section corresponding to the traffic information from the recorded passage time, and the passage time corresponding to the traffic flow included in the traffic information among the selected passage time for each predetermined road section Is extracted, the passage time for each predetermined road section is estimated from the extracted passage time, and the route calculation unit 73 performs route calculation using the estimated passage time. That is, the route guidance device 1 according to the first embodiment of the present invention extracts only the passage time corresponding to the traffic flow included in the traffic information from the passage times recorded in the past, and the extracted passage time. Since route guidance is performed based on the route information, optimum route guidance according to traffic conditions can be performed.

[Overall configuration of route guidance device]
Next, with reference to FIG. 8, the structure of the route guidance apparatus which becomes the 2nd Embodiment of this invention is demonstrated.

  As shown in FIG. 8, the route guidance device according to the second embodiment of the present invention is capable of information communication with the in-vehicle route guidance device A (hereinafter abbreviated as device A) and the device A provided on the vehicle side. It is composed of a route guidance device B outside the vehicle (hereinafter abbreviated as device B). The device A mainly includes a vehicle current position detection unit 2, a map database 4, a display device 6, a communication unit 9a, and a control unit 7a that performs overall control of the device A including these units. On the other hand, the apparatus B mainly includes a traffic information receiving unit 3, a map database 4, a section passing time database 5, a communication unit 8b, and a control unit 7b that performs overall control thereof.

[Details of each component of in-vehicle route guidance device A]
In the device A, the configuration of the vehicle current position detection unit 2, the map database 4, and the display device 6 includes the vehicle current position detection unit 2, the map database 4, and the display device 6 in the route guidance device according to the first embodiment of the present invention. Since the section passing time recording unit 71, the route calculation unit 73, and the presentation unit 74 included in the control unit 7a have the same configuration, the description thereof will be omitted below, and the configuration of the control unit 7a and the communication unit 9a will be described. .

  The control unit 7a is configured by a well-known information processing device, and an internal CPU (Central Processing Unit) executes a program so that the section passing time recording unit 71, the route calculation unit 73, and the presentation unit 74 Realize operation.

  The communication unit 9a transmits and receives necessary data to and from the communication unit 9b that is a component of the device B.

[Details of each component of the exterior route guidance device B]
In the device B, the configuration of the traffic information receiving unit 3 and the section passing database 5 is included in the traffic information receiving unit 3, the section passing time database 5 and the control unit 7b in the route guidance device according to the first embodiment of the present invention. Since the road condition estimation unit 72 has the same configuration, the description thereof will be omitted below, and the configuration of the control unit 7b, the reception information recording unit 8 and the communication unit 9b included in the control unit 7b will be described.

  The control unit 7b is configured by a known information processing device, and the operation of the reception information recording unit 8 and the road condition estimation unit 72 is realized by an internal CPU (Central Processing Unit) executing a program. .

  The reception information recording unit 8 acquires the link passage time data corresponding to the predetermined road section transmitted from the communication unit 9 a from the communication unit 9 b and records it in the section passage time database 5.

  The devices A and B having such a configuration perform optimum database guidance settings according to road conditions by executing the following database generation processing and route guidance processing. Hereinafter, operations of the devices A and B when executing the database generation processing and the route guidance setting will be described.

[Database creation processing]
Next, with reference to the flowcharts shown in FIGS. 9 and 10, the operations of the devices A and B when generating the section passage time database 5 will be described.

  The flowchart shown in FIG. 9 starts in apparatus A when the engine of the vehicle is started or when the power of apparatus A is turned on, and the process proceeds to step S31.

  In step S31, the vehicle current position detection unit 2 acquires current position information and inputs it to the section passage time recording unit 71.

  In step S32, the section passing time recording unit 71 acquires link information corresponding to the current position of the vehicle from the map database 4 based on the input current location information, and the time when the link has passed near the start point of the link; The time required for the vehicle to pass through the link is calculated by obtaining the time passed near the end point and subtracting the time passed near the start point from the time passed near the end point. Then, the section passage time recording unit 71 classifies the calculated passage time for each day of the week and time zone, and outputs data relating to those passage times (passage time data) to the communication unit 9a. The communication unit 9a transmits the output transit time data to the device B, and proceeds to the next step S33 after transmission.

  In step S33, the control unit 7a determines whether or not the vehicle engine is stopped or the apparatus A is turned off. If the vehicle engine is stopped or the apparatus A is turned off, the process is terminated. If not, the process returns to step S31 and the database generation process is repeatedly executed. The above is the database generation process performed by apparatus A.

  Next, database generation processing performed by the device B will be described.

  The flowchart shown in FIG. 10 starts when the communication unit 9b of the apparatus B receives the passage time data transmitted from the communication unit 9a.

  In step S41, the reception information recording unit 8 records the passage time data output from the communication unit 9b in the section passage time database 5. Here, the recording method in the section passage time database 5 is the same as that in the first embodiment, and the reception information recording unit 8 always acquires the passage time information of the road on which the vehicle is actually traveling. The transit time data is transmitted from the communication unit 9a to the device B. In the device B, the passage time data received by the reception information recording unit 8 is recorded in the section passage time database 5.

  In the case of a vehicle equipped with the device A, the passage time data of a predetermined section road from not only the own vehicle but also other vehicles is similarly transmitted to the device B, and the database generation process is performed. By doing so, the passage time database recorded in the database of a predetermined section road increases, and passage time can be estimated more accurately. When the process in step S41 ends, the process proceeds to step S42.

  In step S42, the control unit 7b determines whether to end the database generation process. If the database generation process is to be ended, the database generation process is ended. If not, the process returns to step S41, and the transit time data This is repeated until there is no more reception.

[Route guidance setting process]
Next, with reference to the flowchart shown in FIG. 11, a case where the route guidance setting process is performed will be described.

  In the process of step S51, the road condition estimation unit 72 determines whether or not the traffic information receiving unit 3 has received traffic information from VICS or the like, and if the traffic information is received by the traffic information receiving unit 3, route guidance The setting process proceeds to step S52. On the other hand, when the traffic information receiving unit 3 has not received the traffic information, the route guidance setting process proceeds to the process of step S57.

  Next, the route guidance setting process proceeds to step S52. The route guidance setting process from step S52 to step S56 is performed from step S12 to step S16 of the route guidance setting process in the first embodiment of the present invention. Since this is the same as above, only the processing after step S57 will be described.

  In the process of step S57, the road condition estimation unit 72 outputs the predetermined road section data and the estimated transit time necessary for the route calculation unit 73 on the device A side to calculate the route to the communication unit 9b. The data is transmitted to the communication unit 9a, and the process proceeds to the next step S58.

  In the process of step S58, the control unit 7b determines whether or not to end the route guidance setting process. If the route guidance process is ended, the control unit 7b ends. If not, the process returns to step S51 to return to the route guidance setting process. I do.

  Based on the data transmitted in step S57, route guidance calculation is performed through the same processing as in the first embodiment.

  As is clear from the above description, according to the route guidance device according to the second embodiment of the present invention, the vehicle current position detection unit 2, the section passage time recording unit 71, and the route calculation unit 73 are configured as the in-vehicle route guidance device A. Since the section passing time database 5, the traffic information receiving unit 3, and the road condition estimating unit 72 are provided on the side of the route guidance device B outside the vehicle, the number of parts of the route guidance device mounted on the vehicle side is determined. Can be reduced. In addition, the storage capacity of the section passage time database 5 can be increased.

  As mentioned above, although the embodiment to which the invention made by the present inventor is applied has been described, the present invention is not limited by the description and the drawings that form part of the disclosure of the present invention according to this embodiment. That is, it should be added that other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the above embodiments are all included in the scope of the present invention.

1 is a block diagram of an in-vehicle route guidance apparatus according to a first embodiment of the present invention. It is a flowchart figure which shows the database production | generation process process in the vehicle-mounted route guidance apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the internal structure of the area passage time database used as one Embodiment of this invention. It is a figure which shows the structure of the section in the section passage database shown in FIG. It is a flowchart figure which shows the route guidance setting process in the 1st Embodiment of this invention. It is a figure which shows an example of the map screen at the time of dividing a road condition into three steps. It is a figure which shows an example of the map screen at the time of dividing a road condition into four steps. It is an in-vehicle route guidance device figure and a vehicle outside route guidance device figure concerning a 2nd embodiment of the present invention. It is a flowchart figure which shows the database production | generation process process in the vehicle-mounted route guidance apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart figure which shows the process process of the database production | generation in the route guidance apparatus B outside a vehicle which concerns on the 2nd Embodiment of this invention. It is a flowchart figure which shows the route guidance setting process in the 2nd Embodiment of this invention.

Explanation of symbols

1: vehicle-mounted route guidance device 2: vehicle current position detection unit 3: traffic information reception unit 4: map database 5: section passage time database 6: display device 71: section passage time recording unit 72: road condition estimation unit 73: route Calculation unit 74: presentation unit 7a, 7b: control unit 8: received information recording unit 9a, 9b: communication unit
A: In-vehicle route guidance device
B: Outside route guidance device

Claims (4)

Section passing time calculating means for calculating the passing time for each of a plurality of predetermined road sections, with the time required for the vehicle to pass through the predetermined road section as a passing time;
Recording means for recording the passing time for each predetermined road section;
Traffic information acquisition means for acquiring traffic information including at least information on traffic flow for each predetermined road section around the current position of the vehicle;
Section passage time selection means for selecting a passage time corresponding to a predetermined road section included in the traffic information from the recording means;
Section passage time extraction means for extracting, for each predetermined road section, a passage time corresponding to the traffic flow included in the traffic information among the passage times for each predetermined road section selected by the section passage time selection means;
A section passage time estimation means for calculating an average value of the passage time extracted by the section passage time extraction means for each predetermined road section and estimating a passage time for each predetermined road section included in the traffic information. A characteristic road condition estimation device.   The information on the traffic flow indicates an average speed for each predetermined road section around the current position of the vehicle, the section passage time extracting means stores a passage time range for each of a plurality of speed ranges, and the information on the traffic flow is The speed range including the average speed is determined, the passing time range corresponding to the determined speed range is selected, and the passing time included in the selected passing time range is extracted. Road condition estimation device.   The section passage time calculation means is provided on the vehicle side, and the recording means, traffic information acquisition means, section passage time selection means, section passage time extraction means, and section passage time estimation means are on the processing device side outside the vehicle that can communicate with the vehicle. The road condition estimation apparatus according to claim 1, wherein the road condition estimation apparatus is provided. Calculating a passing time for each of a plurality of predetermined road sections, with a time required for passing the predetermined road section as a passing time;
Recording the passing time for each predetermined road section;
Obtaining traffic information including at least information on traffic flow for each predetermined section road around the current vehicle location;
Selecting a transit time corresponding to a predetermined road section included in the traffic information from the recorded transit time;
Extracting the passage time corresponding to the traffic flow included in the traffic information among the selected passage times for each predetermined road section;
Calculating an average of the extracted passage times for each predetermined road section, and estimating a passage time for each road section included in the traffic information;
The road condition estimation method characterized by having.

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