JP5381808B2 - Traffic information processing apparatus and method for detecting traffic jam information using the same - Google Patents

Description

  The present invention relates to a traffic information processing apparatus that uses vehicle event information included in probe information for detection processing of traffic jam information (for example, a bottleneck intersection), and a traffic jam information detection method executed by this device. .

In the central sensitive control performed by the traffic control center, program selection control is generally adopted, but this requires a lot of labor for parameter design, and redesign when the situation changes due to aging of traffic conditions. There are drawbacks such as the need for an evaluation index (weighted sum of traffic volume and occupation rate) is ambiguous.
Therefore, program formation control for automatically updating signal control parameters in accordance with traffic conditions may be performed as central sensitive control. This control method is called MODERATO (Management by Origin-Destination Related Adaptation for Traffic Optimization) control (see Non-Patent Document 1).

In the central sensitive control, system control is performed in which a road is divided into sub-areas including a plurality of intersections, and signal control parameters such as cycle length and offset are adjusted so that the vehicle can travel appropriately in each sub-area.
In such system control, in general, a vehicle detector installed near an intersection is used to measure the traffic volume by measuring the number of passing vehicles, for example, every 5 minutes. Determine the length of the green time of the traffic signal.

However, for example, at an intersection that becomes a bottleneck in a traffic jam, there is a problem that a vehicle cannot travel easily even if it becomes a green light only by performing the above-described system control, and a wasteful green light time occurs. .
Therefore, an intersection where a bottleneck has occurred (hereinafter sometimes referred to as a “bottleneck intersection”) is detected based on the traffic volume measured by a vehicle sensor provided at each intersection, and this intersection is detected as a sub-area. A traffic control system has been proposed that eliminates traffic congestion by controlling separately from the control (see Patent Document 1).

"Revised Traffic Signal Guide" Editorial and publication Traffic Engineering Research Group (16-18, 83-87)

Japanese Patent Laid-Open No. 2002-230686

In the above-mentioned conventional traffic control system, in order to detect a bottleneck intersection with high accuracy, it is necessary to install a vehicle detector for measuring traffic at each intersection. There are drawbacks.
Therefore, for example, from a probe vehicle traveling on a road, traveling locus information (probe information) including the position and time of the vehicle is uplink transmitted by an optical beacon or the like, and the vehicle is stopped from the position and time included in the probe information. It may be possible to determine the bottleneck intersection and the end of the traffic jam by obtaining the position and stop time.

However, if the position and time generated in the traveling vehicle are uniformly included in the probe information, the amount of data becomes enormous, the efficiency of data storage and transmission in the communication system becomes worse, and the cost increases.
In particular, when uplink information is transmitted to an optical beacon, the amount of transmission data on the uplink side (for example, 59 bytes per frame) is limited in the first place. There is a possibility that it cannot be transmitted by means of inclusion.

On the other hand, paying attention to the stop event that occurs in the running vehicle, the stop event is a single stop that is a stop from a non-congested driving state, and repeated stop and start while driving in a traffic jam section (Stop & go) It can be roughly divided into repeated stop, which is a stop from the running state.
And if you use this stop event, you can estimate the possibility of traffic jam if you can detect the stop position of single stop and the number of repeated stops between them, and even if the stop position of repeat stop is not recorded, Since it can be identified, it is considered efficient.

  In view of such circumstances, an object of the present invention is to enable detection of traffic jam information such as a bottleneck intersection from probe information of an event recording method including a stop event that occurs in a traveling vehicle.

  (1) The first traffic information processing apparatus of the present invention (hereinafter referred to as “first apparatus invention”) uses the event recording type probe information including the stop event generated in the traveling vehicle to detect the congestion information. The probe information in which the stop position of a single stop, which is a stop from a non-congested running state, and the number of repeated stops, which is a stop from a congested running state, is acquired. A plurality of pieces of probe information obtained by acquiring probe data in which there is the repeated stop in the road section between the acquisition means and the two stop positions of the single stop and there is no repeated stop downstream of the road section; And a data collecting means for collecting from the above.

In the first device invention described above, “single stop” recorded in the probe information acquired by the acquisition means is a stop from the non-congested running state, and “repetitive stop” is a stop from the congested running state. If there are repeated stops in the road section between the single stop positions, it can be estimated that the road section is included in the traffic jam section.
In the field of traffic control, “bottleneck” usually means a state on the road or its position where the upstream side is congested and the downstream side is not congested.

For this reason, when there is a road section where traffic congestion is estimated and there is no repeated stop on the downstream side, the next intersection at the downstream end of the road section is a bottleneck intersection. Presumed.
Therefore, in the first device invention, since the data collection means is used for the bottleneck intersection detection process, the data collection means has the repeated stop in the road section between the two single stop positions, and the road section Probe data with no repeated stops on the downstream side is collected from the plurality of acquired probe information.

  (2) Accordingly, in the first device invention, the most downstream end of the plurality of road sections respectively extracted from the probe data having the number of data equal to or greater than a predetermined threshold is obtained, and the nearest intersection on the downstream side of the most downstream end If it is further provided with a determination means for determining as a bottleneck intersection, the bottleneck intersection can be detected from the probe information of the event recording method including the stop event that occurs in the traveling vehicle.

  (3) Further, if the determination means obtains the most upstream end of the plurality of road sections and determines that the most upstream end is the end of the traffic jam, the traffic congestion end can also be determined from the probe information of the event recording method. Can be detected.

  (4) The second traffic information processing apparatus of the present invention (hereinafter referred to as “second apparatus invention”) uses the event recording type probe information including the stop event generated in the traveling vehicle to detect the congestion information. Acquisition means for acquiring the probe information in which an uplink event including the occurrence position of the current event and having the number of repeated stops from the previous event to the current event as incidental information is recorded And probe data including a first event that is a single stop event having the number of repeated stops of 1 or more and a second event that is the next uplink event and has the number of repeat stops of zero. And a data collecting means for collecting from the plurality of probe information.

In the second device invention, the “uplink event” recorded in the probe information acquired by the acquisition means includes the number of repeated stops from the previous event to the current event as accompanying information in addition to the occurrence position of the event. include.
Therefore, when an uplink event (first event) is a single stop event with a number of repeated stops of 1 or more, and the next uplink event (second event) has a number of repeated stops of zero. It is estimated that the next intersection of the first event is a bottleneck intersection.

  Therefore, in the second device invention, the data collection means is used for the bottleneck intersection detection process, and the data collection means includes the first event that is the single stop event whose number of repeated stops is one or more, and the next uplink. Probe data including a second event that is an event and the number of times of repeated stop is zero is collected from a plurality of acquired probe information.

  (5) Therefore, in the second device invention, the most downstream point of the stop positions of the plurality of first events respectively extracted from the probe data having the number of data equal to or greater than a predetermined threshold is obtained, and If a determination means for determining the nearest downstream intersection as the bottleneck intersection is further provided, the bottleneck intersection can be detected from the probe information of the event recording method including the stop event that occurs in the traveling vehicle. .

(6) Further, in the second device invention, the probe data includes a third event that is located on the upstream side of the first event and is the single stop event in which the number of repeated stops is zero. Is preferred.
In this case, the determination means obtains the most upstream point of the stop positions of the plurality of third events respectively extracted from the probe data of the number of data, and determines that the most upstream point is the end of the congestion. The end position can also be detected from the probe information of the event recording method.

  (7) If the section from the end of the traffic jam to the bottleneck intersection is determined as the traffic jam section in the determination means, the length of the traffic jam generated at the bottleneck intersection can also be specified. .

  (8) (9) The first detection method of the present invention is a method for detecting traffic jam information (bottleneck intersection and traffic jam tail) performed by the first device invention, and has the same effect as the first device invention. Play.

  (10) (11) The second detection method of the present invention is a method of detecting traffic jam information (bottleneck intersection and traffic jam tail) performed by the second device invention, and has the same function as the first device 2 invention. There is an effect.

  As described above, according to the present invention, traffic jam information such as a bottleneck intersection can be detected from probe information of an event recording method including a stop event that occurs in a traveling vehicle. Information can be detected accurately.

It is a road top view which shows the traffic information communication system which concerns on embodiment of this invention. It is a table | surface which shows the relationship of the application of the traffic control which a central apparatus performs, a traffic parameter | index, and probe information. It is a functional block diagram which shows the internal structure of a central apparatus. It is a functional block diagram which shows the internal structure of a vehicle-mounted apparatus. It is a graph which shows the determination method of a stop event. It is a road top view which shows the example of a direction change event. It is a table | surface which shows the frame format of probe information. It is a table | surface which shows bit allocation of the various information described in probe information. It is a flowchart which shows the data collection process which the control part of a central apparatus performs, and the determination process of traffic congestion information. It is explanatory drawing which shows the event content of the collected probe data. It is explanatory drawing of the detection process of traffic congestion information.

[Overall system configuration]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a road plan view showing an example of a traffic control system to which the present invention can be applied.
As shown in FIG. 1, the traffic control system of the present embodiment includes a traffic signal 1, a vehicle-mounted device 2, a roadside sensor 3 including a vehicle detector, a central device 4, and a probe vehicle 5 (hereinafter referred to as a vehicle-mounted device 2). It may be simply referred to as a vehicle 5), and an optical beacon 6 or the like.

Among these, the traffic signal machine 1 includes four signal lamps 1b installed on the main roads RM1 and RM2 and the secondary roads RS1 and RS2, and a traffic signal controller connected to the signal lamp unit 1b via a lamp line. 1a.
The traffic signal controller 1a is connected to a central device 4 in the traffic control center via a communication line such as a telephone line, and the central device 4 is a traffic signal controller at each intersection C in its own jurisdiction area. 1a and a local area network (LAN).

  Accordingly, the central device 4 can perform bidirectional communication with the traffic signal controller 1a, and the traffic signal controller 1a can also perform bidirectional communication with the controller 1a at other intersections. The central device 4 may be installed on the road instead of the traffic control center.

The traffic signal controller 1a receives a signal control command S1 which is an output of a result of MODERATO (Management by Origin-Destination Related Adaptation for Traffic Optimization) control or the like from the central device 4, and based on the signal control command S1, The lighting, extinguishing and blinking of the signal lamps included in each signal lamp 1b are controlled.
The traffic signal controller 1a is also connected to an optical beacon 6 which is a kind of a narrow-area wireless communication device through a communication line, and the traffic information S2 including traffic information and travel time received from the central device 4 is transmitted to the optical beacon. 6 to send.

The optical beacon 6 can perform two-way communication with the probe vehicle 5 on which the in-vehicle device 2 is mounted using an optical signal, and transmits the traffic information S2 including the downlink information DL. Further, the uplink information UL transmitted from the in-vehicle device 2 to the optical beacon 6 includes probe information S3 including the travel position and time of the probe vehicle 5.
This information UL is transferred to the central device 4 via the traffic signal controller 1a or directly from the optical beacon 6.

  The central device 4 identifies the optical beacon 6 that has transmitted the uplink information UL to the central device 4 based on the identification number of the communication connection provided between each of the optical beacons 6 and the reception time. Or the approximate reception time when the optical beacon 6 receives the uplink information UL can be specified.

The roadside sensor 3 is, for example, a vehicle detector that senses the vehicle 5 passing directly below by an ultrasonic method, a loop coil that senses the vehicle 5 by an inductance change, or an image of a camera image to process traffic volume or vehicle It consists of an image sensor that measures the speed, and is installed on some roads in the jurisdiction area for the purpose of measuring the number of vehicles flowing into the intersection C and the vehicle speed.
The roadside measurement information S4 detected by the roadside sensor 3 is relayed by the traffic signal controller 1a or transmitted directly from the roadside sensor 3 to the central device 4 via a communication line.

[Central equipment (traffic information processing equipment)]
FIG. 3 is a functional block diagram showing the internal configuration of the central device 4.
As illustrated in FIG. 3, the central device 4 that functions as a traffic information processing device includes a control unit 401, a display unit 402, a communication unit 403, a storage unit 404, and an operation unit 405.
The control unit 401 of the central device 4 includes a workstation (WS), a personal computer (PC), etc., and collects / processes (calculates) / records various traffic information from the traffic signal controller 1a, controls signals, and provides information. Is performed in an integrated manner. Note that the control unit 401 of the central device 4 is connected to the hardware units via an internal bus, and also controls the operations of these units.

The control unit 401 of the central device 4 controls the traffic signal controller 1a belonging to its own jurisdiction area by adjusting the traffic signal group 1 on the same road, or wide-area control that extends this system control to the road network. (Surface control) can be executed.
That is, the control unit 401 of the central device 4 sets signal control parameters (split, cycle length, offset, etc.) according to traffic conditions. The control performed by the control unit 401 includes, for example, the MODERATO control and the Multiple types including profile control and the like are included.

The communication unit 403 of the central device 4 is a communication interface connected to the LAN side via a communication line, and includes a signal control command S1 relating to the timing of switching the color of the signal lamp 1b every predetermined time, and the travel time of the road link. Traffic information S2 including traffic information and traffic information is transmitted to the optical beacon 6 or directly to the optical beacon 6 via each traffic signal 1.
The signal control command S1 is transmitted every signal control parameter calculation cycle (for example, 1.0 to 2.5 minutes), and the traffic information S2 is transmitted every five minutes, for example.

  Further, the communication unit 403 of the central device 4 includes the uplink information UL having probe information S3 that is movement measurement information including the travel position and time (trajectory) measured by the probe vehicle 5 and the vehicle ID, and the roadside sensor 3. The measured roadside measurement information S4 is received from the traffic signal controller 1a, the optical beacon 6, or the like.

The display unit 402 of the central device 4 includes a road map of an area managed by the central device 4 and a display screen on which the position of the traffic signal 1, the roadside sensor 3, and the optical beacon 6 on the road map is displayed. Informs traffic conditions such as traffic jams and accidents.
The operation unit 405 of the central device 4 includes an input interface such as a keyboard and a mouse. The operation unit 405 allows the central operator to perform a display switching operation on the display unit 402.

The storage unit 404 of the central device 4 includes a hard disk, a semiconductor memory, and the like, and stores a control program for the traffic signal control and a traffic index calculation program used for the traffic signal control. It also has a temporary storage area for the signal control command S1 and traffic information S2 generated by the unit 401.
The storage unit 404 of the central device 4 includes a probe database DB1, a roadside database DB2, and a map database DB3.

The probe database DB1 includes various measurement values (passage position and time of the probe vehicle 5 and the event type thereof) included in the probe information S3 of the uplink information UL, and passage at the link start and end estimated from the measurement values. Time etc. are accumulated.
In the roadside database DB2, various measurement values of the roadside measurement information S4 (the number of passing vehicles with respect to the vehicle link, etc.) are accumulated.

The road map data in the map database DB3 is associated with the intersection data in which the intersection ID and the position of the intersection are associated, and the beacon ID and the installation position of the optical beacon 6 (or may be a road-to-vehicle communication position). And beacon data.
The road map data includes the link ID, the link start point / end point / interpolation point (corresponding to the point where the road bends), the link ID of the link connected to the link start point, and the link end point. Link data that associates the link ID of the link to be connected is also included.

Based on the roadside measurement information S4 accumulated in the roadside database DB2, the control unit 401 of the central device 4 calculates the estimated travel time of each link for every predetermined time, and records this estimated value in the map database DB3.
Instead of the central device 4 itself estimating the estimated travel time of each link based on the roadside measurement information S4 from the roadside sensor 3, each link from a traffic information distribution center such as a VICS center ("VICS" is a registered trademark) is used. The estimated travel time (ie, “VICS travel time”) may be acquired.

  In addition, the estimated travel time of each link is usually a past estimated value that is updated every 5 minutes based on the latest roadside measurement information S4. It may be a predicted value of travel time of each link for the future obtained using a prediction algorithm.

The control unit 401 of the central device 4 collects probe data used for detection processing of traffic jam information from the probe information S3 of each vehicle 5 included in the uplink information UL acquired from the optical beacon 6; Then, the “congestion information detection process” is executed to detect the bottleneck intersection and the end of the traffic jam using the collected probe data.
The details of the “data collection process” and “congestion information detection process” will be described later.

[Types of traffic control by central equipment]
FIG. 2 is a table showing the relationship between the traffic control application executed by the control unit 401 of the central apparatus 4, the traffic index that is input information necessary for the application, and the probe information necessary for calculating the traffic index. It is.
For example, the traffic indicators (input information for traffic control) necessary for MODERATO control and profile control implemented for the advancement of signal control are the number of queues and saturated traffic flow rate, which are necessary for detour priority control. Traffic indicators are travel time and travel route.

The traffic index necessary for detecting the bottleneck position, which is implemented for the traffic flow analysis, is the number of stops of the vehicle 5 that is running.
Furthermore, the estimation of CO2 emissions performed by MOCS requires the number of stops of vehicle 5 (in this case, it is necessary to distinguish between repeated stop and single stop described later). The traffic index necessary for management is the travel route of the vehicle 5.

[In-vehicle device (mobile terminal device)]
FIG. 4 is a functional block diagram showing the internal configuration of the in-vehicle device 2 of the probe vehicle 5.
The in-vehicle device 2 that is a mobile terminal device mounted on the probe vehicle 5 has a road-to-vehicle communication function that performs bidirectional optical communication with the optical beacon 6 and a navigation function that guides the destination set by the passenger. Have.
As shown in FIG. 4, the in-vehicle device 2 includes a GPS processing unit 201, a direction sensor 202, a vehicle speed acquisition unit 203, an optical communication unit 204, a storage unit 205, an operation unit 206, a display unit 207, an audio output unit 208, and a control unit. 209 etc.

The GPS processing unit 201 receives a GPS signal from a GPS satellite, and based on time information included in the GPS signal, an orbit of the GPS satellite, positioning correction information, and the like, the probe vehicle 5 that is traveling in the reference coordinate system The absolute position latitude, longitude and altitude can be measured in real time.
The direction sensor 202 is constituted by an optical fiber gyro or the like, and measures the direction and angular velocity of the probe vehicle 5. The vehicle speed acquisition unit 203 acquires speed data of the probe vehicle 5 measured by a vehicle speed sensor (not shown) detecting the angular speed of the wheels.

The optical communication unit 204 of the in-vehicle device 2 transmits and receives the uplink information UL and the downlink information DL in the communication area of the optical beacon 6 set at a predetermined position on the road. That is, when the probe vehicle 5 that has flowed out of the intersection C enters the communication area of the optical beacon 6, the optical communication unit 204 of the in-vehicle device 2 receives the downlink information DL including the traffic information S <b> 2 and receives its own probe information S <b> 3. The included uplink information UL is transmitted to the optical beacon 6.
The storage unit 205 of the in-vehicle device 2 includes a hard disk, a semiconductor memory, and the like, and a storage area for storing various information such as traffic information S2 included in the downlink information DL and probe information S3 included in the uplink information UL. Have

The storage unit 205 also stores road map data. This road map data includes intersection data in which intersection IDs are associated with intersection positions.
The road map data includes the link ID, the link start point, end point, and interpolation point (corresponding to the points where the road bends), the link ID of the link connected to the link start point, and the link connected to the link end point. Link data in which the link ID is associated with the link cost used for specifying the optimum route is also included.

For example, the number of link costs is the same as the number of links and links connected to the end point, and after entering the start point of the link, the end point of the link is exited, and the start point of the next link to be connected is entered. The time required to do is set.
That is, the link cost includes the cost (time) required to travel from the start point to the end point of the link and the cost (time) required to travel from the end point of the link to the start point of the next link, that is, the intersection. The cost required to pass is included.

The operation unit 206 of the in-vehicle device 2 includes a touch panel, buttons, and the like, and a passenger of the vehicle 5 including a driver can set a destination.
The display unit 207 of the in-vehicle device 2 includes a monitor device (not shown) attached to the dashboard portion of the vehicle 5, and displays image data created by the control unit 209 in the sensitivity request process described later to the passenger. The audio output unit 208 outputs the audio data created by the control unit 209 from a speaker (not shown).

The control unit 209 of the in-vehicle device 2 includes a microcomputer or the like, and includes a GPS processing unit 201, a direction sensor 202, a vehicle speed acquisition unit 203, an optical communication unit 204, a storage unit 205, an operation unit 206, a display unit 207, and an audio output unit. Each process in 208 is controlled.
Further, the control unit 209 of the in-vehicle device 2 includes the absolute position (latitude and longitude) of the vehicle 5 measured by the GPS processing unit 201, the azimuth and angular velocity of the vehicle 5 measured by the azimuth sensor 202, and the vehicle 5 acquired by the vehicle speed acquisition unit 203. The position of the probe vehicle 5 on the road link can be calculated by performing the map matching process based on the speed data and the road map data stored in the storage unit 205.

  Furthermore, in the storage unit 205 of the in-vehicle device 2, “event determination processing” for determining the occurrence of various events that occur during the traveling of the probe vehicle 5, and the event and its relation according to the nature of the various events. A computer program for determining which of the information to include in the probe information S3 and causing the control unit 209 to execute an “information generation process” for generating the probe information S3 for each event is stored.

The control unit 209 of the in-vehicle device 2 executes the “event determination process” and the “information generation process” by reading the program from the storage unit 205 and executing the program. Hereinafter, these processes which the control part 209 of the vehicle-mounted apparatus 2 performs are demonstrated.
In the present embodiment, since the optical beacon 6 is used as a means for transmitting the probe information S3 to the infrastructure side, the control unit 209 of the in-vehicle device 2 causes the optical beacon 6 to pass next to the optical beacon 6. Probe information S3 describing various events that occurred during traveling on the route between the two and related information is generated.

[Content of processing related to stop event]
The stop events determined by the control unit 209 of the present embodiment include “independent stop” and “repetitive stop”.
FIG. 5 is a graph showing a method for determining whether to stop alone or repeatedly. In the graph of FIG. 5, the horizontal axis is the travel distance of the vehicle 5, and the vertical axis is the speed.
Further, the first threshold value V1 in FIG. 5 is a threshold value for determining whether the stop of the vehicle 5 is repeated stop or single stop, and is set to 30 km / h, for example. The second threshold value V2 is a value that can be regarded as a substantial stop when the speed is less than this, and is set to, for example, 5 km / h.

Here, “independent stop” refers to a stop from a non-congested traveling state, and corresponds to a signal waiting stop at a non-congested intersection or an initial stop at a congested intersection. The “repetitive stop” is a stop from the traffic running state, and is an event assuming a case where the vehicle 5 repeatedly stops and starts due to the traffic jam (Stop & Go).
For example, as indicated by points A and B in FIG. 5, the speed of the vehicle 5 decreases from a state where it exceeds the first threshold value (speed threshold value for determining traffic congestion) V1, and the speed is reduced to the second threshold value (for determining stoppage). Speed threshold) V2 and the vehicle 5 stops, it is determined as “independent stop”.

On the other hand, when the speed of the vehicle 5 increases or decreases within the range less than the first threshold value V1, and the speed of the vehicle 5 falls below the second threshold value V2 and stops as shown in FIG. , “Repetition stop” is determined. Under the above determination conditions, the control unit 209 of the in-vehicle device 2 executes the following processes (1) to (6).
(1) First, the control unit 209 clears all of the number of repeated stops, the number of independent stops, the restart time and stop position, and the high-speed traveling flag at the time of activation.

(2) Next, the control unit 209 monitors the speed of the vehicle 5 every predetermined time (for example, 1 second) set in advance, and if this speed is equal to or higher than the first threshold value V1, the high-speed running flag Set to on.
(3) Next, the control unit 209 determines that the vehicle 5 has stopped when the state where the speed is less than the second threshold value V2 continues for a certain number of seconds (constant setting: for example, 5 seconds).

In this case, when the high-speed traveling flag is on, the vehicle 5 can be regarded as being in the state of point A or point B in FIG. 5, so the number of independent stops is incremented, and when the high-speed flag is off, Since the point C can be regarded as being in a state, the number of repeated stops is incremented.
(4) Further, after determining that the vehicle 5 is stopped, the control unit 209 determines that the vehicle 5 has restarted when the speed exceeds the second threshold value V2. At this time, if the high-speed running flag is on, it corresponds to the case of single stop, so that the restart time, stop position and stop time are stored in the storage unit 205.

However, the control unit 209 previously sets a limited number (constant setting: for example, 5 times) that can be included in the probe information S3 for the single stop event with a stop position.
Therefore, when the number of single stops from the previous uplink information UL exceeds the above-mentioned limited number, the control unit 209 overwrites the oldest data, for example, and restarts the single stop, stop position, and stop time. Update. In addition, the control unit 209 finally sets the high speed travel flag to OFF.

(5) The control unit 209 repeats the processes (2) to (4) until communication with the next optical beacon 6 occurs.
(6) Further, the control unit 209 performs generation processing of probe information S3 including the following event information (a) until communication with the next optical beacon 6 occurs, and at the time of passing, the probe information S3 Is included in the uplink information UL and transmitted to the optical communication unit 204.

(A) Single stop event information-Stop position, restart time and stop time-Number of repeated stops that occurred before the single stop from the previous uplink event-Before the single stop from the previous uplink event Number of independent stops that occurred and are no longer uplink events due to data updates

In this specification, the “uplink event” is an event included in the probe information S3 as an event having at least position information, and will be described later in addition to the single stop event (a) having a stop position. This includes a direction change event or a constant distance event.
Note that after the transmission of the uplink information UL to the optical beacon 6, the control unit 209 clears all the stop position, the restart time, and the stop time that constitute the single stop event information as the uplink event.

As described above, when the stop event is a single stop, the control unit 209 includes the stop position, the restart time, and the stop time in the probe information S3 for those within a predetermined limited number (for example, five times). However, the stop position, the restart time, and the stop time are not included in the probe information S3 for the single stop whose data has been updated because the limit number has been exceeded and for all repeated stops.
However, the number of single stop and repeated stop is included in the probe information S3 as event information associated with the next uplink event.

  According to the in-vehicle device 2 of the present embodiment, the control unit 209 determines a single stop caused by waiting for a signal or the like and a repeated stop that repeats the stop and start as separate events, and the number of queues and the saturated traffic flow rate For the single stop required for the calculation of the number of events, the information below the predetermined limited number includes the stop position, restart time and stop time as event information. Included in the information.

Accordingly, it is possible to generate the probe information S3 that can calculate the traffic index such as the number of queues and the saturated traffic flow rate while efficiently using the data amount for storing and transmitting the probe information S3.
In addition, since the number of stops is included in the event information of each uplink event so that it is possible to distinguish between a single stop and a repeated stop, the central device 4 that has acquired the probe information S3 from the in-vehicle device 2 Using the number of stops included in the link event, it is possible to estimate the CO2 emission amount by MOCS.

[Content of processing related to direction change events]
FIG. 6 is a road plan view showing an example of a direction change event.
FIG. 6A shows a direction change event that occurs on a right turn at an intersection (however, a left turn may be used), and FIG. 6B shows a direction change event that occurs on a relatively sharply curved single road. .
The control unit 209 of the in-vehicle device 2 extracts “direction fluctuation” having a small curvature radius and a large change in the traveling direction of the vehicle 5 as an event as shown in FIG. 6, and generates probe information S3 related thereto. The following processes (1) to (5) are executed.

(1) First, the control unit 209 monitors the traveling locus of the vehicle 2 every certain time (constant setting: for example 1 second), and the vehicle 5 is constant from the previous locus stored in the storage unit 205 last time. If the vehicle travels more than a distance (constant setting: 10 m, for example), the storage unit 205 stores the position (latitude and longitude) and direction (if not found from the relative position with respect to the previous time) as the current locus.
(2) Next, if the azimuth difference between the previous trajectory and the current trajectory is equal to or greater than a certain value (constant setting: 5 degrees, for example), the control unit 209 regards that the azimuth change has started.

(3) Furthermore, the control unit 209 determines that the azimuth difference between the previous trajectory and the current trajectory is less than a certain value (constant setting: for example, 5 degrees) and the number of times is constant (constant setting: for example, twice). The direction change is considered complete.
(4) Next, if the difference between the azimuth at the start of the azimuth change and the azimuth at the end of the azimuth change is equal to or greater than a certain value (constant setting: 30 degrees, for example), the control unit 209 It is considered that an event has occurred, and the storage unit 205 stores the time, position, and direction at the end of the direction change.

However, the control unit 209 previously sets a limited number (constant setting: for example, twice) that can be included in the probe information S3 for the direction change event and the fixed distance travel event described later, separately from the single stop. doing.
Therefore, when the total number of these events from the previous uplink information UL exceeds the limited number, the control unit 209 overwrites the oldest data, and ends the direction change end time, end position, and absolute Clear the bearing.

(5) The control unit 209 repeats the processes (1) to (4) until communication with the next optical beacon 6 occurs.
(6) Further, the control unit 209 performs generation processing of the probe information S3 including the following event information (b) until communication with the next optical beacon 6 occurs, and when passing, the probe information S3 Is included in the uplink information UL and transmitted to the optical communication unit 204.

(B) Direction change event information-Direction change end time, end position and absolute direction-Number of repetitive stops that occurred before the direction change from the previous uplink event-Direction change change from the previous uplink event Number of previous single outages that were no longer uplink events due to data updates

  In addition, after transmitting the uplink information UL to the optical beacon 6, the control unit 209 clears all of the azimuth change end time, end position, and absolute azimuth constituting the direction change event information as the uplink event. .

[Contents of processing related to fixed-distance driving events]
The control unit 209 of the in-vehicle device 2 determines whether or not the vehicle 5 has traveled for a sufficiently long constant distance (determined distance travel) as an event, and generates probe information S3 related to this, so Execute (4).

(1) First, the control unit 209 clears the accumulated travel distance when either the stop event (single stop or repeated stop) or the direction change event occurs. The control unit 209 also clears the cumulative travel distance even when a direction change event occurs before the cumulative travel distance exceeds a certain distance (constant setting: for example, 500 m).
(2) Next, the control unit 209 monitors the travel locus every predetermined time (constant setting: for example, 1 second), and integrates the travel distance from the previous event.

(3) If the cumulative travel distance exceeds a certain distance (constant setting: 500 m, for example), the control unit 209 considers that a certain distance travel event has occurred and stores the time, position, and direction in the storage unit 205.
However, as described above, a limited number (constant setting: for example, 2 times) is set for the total number of directional fluctuations and constant distance travel, so the total number of those events from the previous uplink information UL is limited. If the number is exceeded, the oldest data is overwritten and the accumulated mileage is cleared.

(4) The control unit 209 repeats the processes (1) to (3) until communication with the next optical beacon 6 occurs.
(5) Further, the control unit 209 performs generation processing of probe information S3 including the following event information (c) until communication with the next optical beacon 6 occurs. Is included in the uplink information UL and transmitted to the optical communication unit 204.

(C) Event information of constant distance travel ・ End time, position and cumulative travel distance of constant distance travel ・ Number of repeated stops that occurred before the predetermined distance travel from the previous uplink event ・ From the previous uplink event Number of independent stops that occurred before a certain distance and were no longer an uplink event due to data update

  Note that after the transmission of the uplink information UL to the optical beacon 6, the control unit 209 clears all the travel end time, position, and cumulative travel distance that constitute the event information of a fixed distance travel as an uplink event. To do.

[Exception handling for stop events]
By the way, the point P of Fig.6 (a) has shown the stop position in the intersection at the time of a right turn. Here, when there is no preceding vehicle on the right turn lane, the traveling vehicle 5 decelerates to a point P that is less than the second threshold value V2, and a single stop or a repeated stop may occur at the point P.
However, the point P in the intersection is irrelevant to signal waiting, and is not necessary for calculating the number of queues and the saturated traffic flow rate. If this is adopted as a stop event, useless probe information S3 is included. Uplink information UL is sent to the infrastructure side.

Therefore, the control unit 209 of the in-vehicle device 2 refers to the road map data included in the storage unit 205, and based on which position in the road map data the traveling position of the vehicle 5 is changing the direction. It is determined whether or not the stop event of the vehicle 5 is a right turn stop that is a stop within an intersection at the time of a right turn as indicated by a point P in FIG. 6 (a). It is not adopted as a single stop or repeated stop.
In other words, the control unit 209 processes the right turn stop as a stop event that is not included in the probe information S3 without being an uplink event.

On the other hand, a point Q in FIG. 6B indicates the stop position of the vehicle 5 during the direction change on a relatively sharp single road. Here, when the signal at the intersection on the downstream side of the single road is red, the traveling vehicle 5 decelerates to a value less than the second threshold value V2 at the point Q, and stops alone or repeatedly at the point Q. May occur.
Therefore, it is considered that the stop at the point Q during the direction change on a single road is necessary for calculating the number of queues and the saturated traffic flow rate, unlike the case of the right turn in FIG. The stop event should be included in the probe information S3.

Therefore, the control unit 209 of the in-vehicle device 2 refers to the road map data included in the storage unit 205, and based on which position in the road map data the traveling position of the vehicle 5 is changing the direction. It is determined whether or not the stop event of the vehicle 5 is a single road stop that is a stop during a change of direction on a single road, as indicated by a point Q in FIG. 6B. This is adopted as a single stop or repeated stop.
That is, the control unit 209 processes the single path stop as a stop event included in the probe information S3.

[Frame contents of probe information]
FIG. 7 is a table showing a frame format of the probe information S3 generated by the control unit 209 of the in-vehicle device 2.
As shown in FIG. 7, the data area of the probe information S3 includes a header, basic items, and attribute types, and the header can describe the number of independent stops and the number of repeated stops.

In addition, the basic item includes a position and measurement time description area, the position is described in latitude and longitude, and the measurement time is described in hours, minutes, and seconds.
Further, the attribute item includes an event type and event value description area. In the event type, the type or flag is described, and in the event value, at least one of direction, stop time, and travel distance is described as a value corresponding to the event type.

[Probe information bit assignment]
FIG. 8 is a table showing bit allocation of various information described in the probe information S3.
As shown in FIG. 8, the stop time in the case of a single stop is represented by 8 bits, divided into the case of second and minute by the initial bit value, and the time is represented by the remaining 7 bits. For this reason, the time from 0x01 (1 second) to 0xff (127 minutes) can be allocated in hexadecimal with 1 second as the minimum unit.

Further, the absolute direction in the case of the direction change is assigned as 16 units in the clockwise direction with “1” in the north.
Furthermore, 8 bits are assigned to the travel distance from the previous event in the case of constant distance travel or direction change, and is in units of 5 m. In this case, a travel distance from 0x01 (5 m) to 0xff (1275 m) can be assigned in hexadecimal.

[Data collection processing by central unit]
As described above, in the present embodiment, the control unit 401 of the central device 4 collects probe data used for detection processing of traffic jam information from the probe information S3 generated by each probe vehicle 5; The “congestion information detection process” is performed using the probe data.
FIG. 9 is a flowchart showing the above processes. Hereinafter, the contents of each process will be described with reference to FIG.

In FIG. 9, n is the “number of repeated stops”, the triangle indicates “independent stop event”, and the circle indicates “uplink event” (independent stop, direction change, and fixed distance travel event). Good).
As shown in FIG. 9, the control unit 401 of the central device 4 first repeats the number n of repeated stops from a plurality of probe information S3 acquired by the communication unit 401 every predetermined time span (for example, 10 minutes). Collects probe data including one or more single stop events (hereinafter referred to as “first event E1”) (step ST1 in FIG. 9).

  Further, the control unit 401 selects an uplink event (hereinafter referred to as “second event E2”) in which the number n of repeated stops is zero on the downstream side of the first event E1 from the data collected in step ST1. Probe data is collected (step ST2 in FIG. 9), and further, the single stop event (hereinafter referred to as “the first stop event) that is located upstream of the first event E1 and has the number of repeated stops n of zero. Probe data including 3 events E3 ”) (step ST3 in FIG. 9).

Here, since all of the probe data collected as described above has repeated stops in the road section between the event E3 and the event E1, it is estimated that traffic congestion has occurred in the road section. Can do.
The reason for this is that, as described above, “independent stop” is a stop from a non-congested driving state, such as a signal waiting stop at a non-congested intersection or the first stop at a congested intersection, The “repetitive stop” is a stop from the traffic running state, and is an event that assumes the case where the vehicle 5 repeatedly stops and starts due to the traffic jam (Stop & Go).

  On the other hand, the “bottleneck” is a state or a position on a road where the upstream side is congested and the downstream side is not congested, and therefore the downstream of the road section from the event E3 to the event E1 where the congestion is estimated. When the repeated stop is not recognized on the side, that is, on the downstream side of the first event E1, it is estimated that the next intersection at the downstream end of the road section is a “bottleneck intersection”.

  The reason is that in order to pass through the bottleneck intersection during traffic jams, multiple signal stoppages usually occur, but at the intersection upstream of the bottleneck intersection, even if the signal is green, the signal waiting vehicle at the downstream intersection Since a phenomenon called so-called “clogging” occurs, in which the vehicle 5 cannot start because the vehicle 5 extends immediately downstream of the intersection, there is a possibility that the time during which the vehicle 5 can actually travel is shortened and the traveling speed of the vehicle 5 does not increase. On the other hand, at the bottleneck intersection, this kind of clogging does not occur, so there is a signal waiting, but there is a high possibility that the traveling speed of the vehicle 5 will increase, so the number of repeated stops before the bottleneck intersection It is highly probable that a single stop event (first event) with n equal to or greater than 1 will occur, and the congestion will be resolved after the bottleneck intersection. n is it is considered that one or more uplink event is very small or no to be present.

Therefore, when the data collection of the probe data including the events E1 to E3 is completed, the control unit 401 of the central device 4 performs a statistical process on the collected probe data to detect the bottleneck intersection and the traffic jam end. .
Specifically, the control unit 401 determines whether or not the number of data is equal to or greater than a predetermined threshold p (step ST4 in FIG. 9), and if the number of data equal to or greater than the threshold p is collected, A neck intersection detection process (step ST5 in FIG. 9) and a congestion end detection process (step ST6 in FIG. 9) are executed.

FIG. 10 is an explanatory diagram showing event contents of collected probe data.
D1, d2, d3... Dk−1, dk in FIG. 10 are the collected probe data, and the probe data di (i = 1 to k) is obtained from the result of the map matching process performed by the control unit 401. It is assumed that both are traveling trajectories passing through the intersections C1 to C8.
The probe data di includes the first to third events E1 to E3, but there is a possibility of traffic jam from the third event E3 to the first event E1 in the section between the events E1 to E3. “Road section” is indicated by a bold line.

[Congestion information detection processing by the central unit]
FIG. 11 is an explanatory diagram showing the traffic jam information detection process when the probe data di of FIG. 10 is obtained.
As shown in FIG. 11, the control unit 401 of the central device 4 extracts the first events E1 from the probe data di having the number of data equal to or greater than a predetermined threshold value p, and the first event having the number of data equal to or greater than p. A most downstream point Md located on the most downstream side is determined from E1. In the example of FIG. 11, the first event E1 of the probe data d2 is the most downstream point Md.

In the process of obtaining the most downstream point Md, road sections (thick line sections in FIG. 11) each having a possibility of traffic congestion are extracted from the probe data di having the number of data equal to or greater than the threshold value p, and the p or more data It may be a process of obtaining the most downstream end (the same position as the most downstream point Md) located on the most downstream side from among the downstream ends of a number of road sections.
Then, after obtaining the most downstream point Md, the control unit 401 determines that the nearest intersection (intersection C6 in FIG. 11) on the downstream side of the most downstream point Md is a bottleneck intersection.

  Further, the control unit 401 of the central device 4 extracts the third events E3 from the probe data di having the number of data equal to or greater than the predetermined threshold p, and from among the third events E1 having the number of data equal to or greater than p, The most upstream point Mu located on the most upstream side is obtained, and this most upstream point Mu is determined to be the end of the traffic jam. In the example of FIG. 11, the third event E3 of the probe data dk is the most upstream point Mu.

In the process for obtaining the most upstream point Mu, a road section (thick line section in FIG. 11) with a possibility of traffic jam extracted from the probe data di having the number of data equal to or greater than the threshold value p is extracted, and the p or more are extracted. The processing may be to obtain the most upstream end (the same position as the most upstream point Mu) located on the most upstream side from the upstream ends of the road section having the number of data.
Then, the control unit 401 of the central device 4 determines the section (hatched section in FIG. 11) from the tail of the traffic jam (the most upstream point Mu) detected as described above to the bottleneck intersection C6 as the traffic jam section, and this traffic jam. Traffic information S2 including links and total extensions belonging to the section is generated.

In the collected probe data di (i = 1 to k), as shown by the data dk−1 in FIG. 10, the vehicle 5 in which the first event E1 occurs considerably upstream of the intersection C5, that is, The vehicle 5 may include a vehicle 5 that sufficiently increases in speed before the bottleneck intersection C6 and does not repeatedly stop before the bottleneck intersection C6.
In this regard, in the present embodiment, the most downstream point Md is determined from the first event E1 having the number of data equal to or greater than the predetermined threshold value p. Therefore, even if such rare case probe data dk-1 is included, the most downstream point Md is included. The downstream point Md can be accurately determined.

When the bottleneck intersection C6 is found, the control unit 401 of the central device 4 separates from the normal system control, and extends the green signal time for giving the right of passage to the bottleneck intersection C6 by a certain period. Is transmitted to the traffic signal controller 1a at the intersection C6.
Thereby, the passage of the vehicle 5 from the bottleneck intersection C6 becomes smoother, and it can be expected that the congestion section is eliminated or alleviated.

  As described above, according to the central device (traffic signal processing device) 4 of the present embodiment, probe information S3 having an uplink event accompanied by the number of times of repeated stop is acquired, and repeated stop is performed from the probe information S3. Since the probe data di including the single stop event (first event E1) in which the number of times n is 1 or more and the uplink event (second event E2) in which the number n of the next repeated stop is zero, By performing statistical processing on the probe data di, it is possible to determine which intersections C1 to C8 are bottleneck intersections.

Further, in the present embodiment, the probe data di collected by the central device 4 includes a single stop event (third event E3) that is located upstream of the first event E1 and the number of repeated stops n is zero. Therefore, by performing statistical processing on the collected probe data di, it is possible to identify the end point of the traffic jam.
As described above, the central device 4 of the present embodiment can detect the bottleneck intersection and the end of the traffic jam using the probe information S3 of the event recording method including the stop event that occurs in the traveling vehicle 5, so that the vehicle detector 3 It is possible to request traffic information without adding more.

[Other variations]
The above embodiment is merely an example, and does not limit the scope of rights of the present invention. The scope of the present invention is defined by the terms of the claims, and all modifications within the scope and equivalents of the claims are included in the present invention.

For example, in the above-described embodiment, the optical beacon 6 is employed as a means for transmitting the probe information S3 in the uplink, but for example, other narrow-area wireless communication means such as ETC, and a wide-area such as a mobile phone and WiMAX. The probe information S3 may be uplink transmitted by wireless communication means.
Furthermore, the present invention is not limited to the case where the central device 4 performs information processing on the probe information S3, and a plurality of traffic signal controllers 1a and other information relay devices included in the LAN perform the information processing. You may do it.

DESCRIPTION OF SYMBOLS 1 Traffic signal device 1a Traffic signal control device 2 In-vehicle device 3 Roadside sensor 4 Central device (traffic information processing device)
5 Probe vehicle 6 Optical beacon 401 Control unit (data collection means, determination means)
403 communication unit (acquisition means)
404 storage)
S1 Signal control command S2 Traffic information S3 Probe information S4 Roadside measurement information di Probe data UL Uplink information DL Downlink information

Claims (11)

A traffic information processing apparatus that uses probe information of an event recording method including a stop event that occurs in a traveling vehicle for detection processing of traffic jam information,
An acquisition means for acquiring the probe information in which the stop position of a single stop that is a stop from a non-congested running state and the number of repeated stops that are a stop from a congested running state are recorded;
Collect probe data from a plurality of the acquired probe information in which the repeated stop exists in the road section between the two stop positions of the single stop and the repeated stop does not exist on the downstream side of the road section. Data collection means to
A traffic information processing apparatus comprising:   Determination means for obtaining the most downstream end of the plurality of road sections respectively extracted from the probe data having a number of data equal to or greater than a predetermined threshold, and determining the nearest intersection on the downstream side of the most downstream end as a bottleneck intersection; The traffic information processing apparatus according to claim 1 provided.   The traffic information processing apparatus according to claim 2, wherein the determination unit obtains the most upstream end of the plurality of road sections, and determines the most upstream end as a traffic jam end. A traffic information processing apparatus that uses probe information of an event recording method including a stop event that occurs in a traveling vehicle for detection processing of traffic jam information,
An acquisition means for acquiring the probe information in which an uplink event including the occurrence position of the current event and having the number of repeated stops from the previous event to the current event as incidental information is recorded;
Probe data including a first event that is a single stop event with the number of repeated stops of 1 or more and a second event that is the next uplink event and has the number of repeated stops of zero is acquired. Data collection means for collecting from a plurality of the probe information;
A traffic information processing apparatus comprising:   The most downstream point among the stop positions of the plurality of first events respectively extracted from the probe data having a data number equal to or greater than a predetermined threshold is obtained, and the closest intersection downstream of the most downstream point is determined as the bottleneck intersection. The traffic information processing apparatus according to claim 4, further comprising determination means for performing. The probe data includes a third event that is located on the upstream side of the first event and is the single stop event with the number of repeated stops being zero,
The said determination means calculates | requires the most upstream point among the stop positions of the said 3rd event each extracted from the said probe data of the said number of data, and determines this upstream point as the congestion end. Traffic information processing equipment.   The traffic information processing apparatus according to claim 3 or 6, wherein the determination unit determines a section from the end of the traffic jam to the bottleneck intersection as a traffic jam section. Obtaining probe information capable of recording a stop position of a single stop, which is a stop from a non-congested running state, and a repeated stop, which is a stop from the time of traffic running, occurring between the stop positions;
Collecting probe data from among the plurality of acquired probe information, in which the repeated stop exists in a road section between the two single stops and the repeated stop is not present downstream of the road section; ,
Determining the most downstream points of the plurality of road sections respectively extracted from the probe data having a number of data equal to or greater than a predetermined threshold, and determining the nearest intersection on the downstream side of the most downstream end as a bottleneck intersection;
A method for detecting traffic jam information, comprising:   The method for detecting traffic jam information according to claim 8, further comprising the step of obtaining the most upstream edge of the plurality of road sections and determining the upstreammost stream edge as a traffic jam end. Acquiring the probe information in which an uplink event including the occurrence position of the current event and having the number of repeated stops from the previous event to the current event as incidental information is recorded;
The probe data including a first event that is a single stop event with the number of repeated stops equal to or greater than 1 and a second event that is the next uplink event and the number of repeat stops is zero. Collecting from a plurality of said probe information;
The most downstream point among the stop positions of the plurality of first events respectively extracted from the probe data having a data number equal to or greater than a predetermined threshold is obtained, and the closest intersection downstream of the most downstream point is determined as the bottleneck intersection. And steps to
A method for detecting traffic jam information, comprising: The probe data includes a pre-third event that is located on the upstream side of the first event and is the single stop event with the number of repeated stops being zero,
11. The method according to claim 10, further comprising: obtaining a most upstream point among a plurality of stop positions of the third events respectively extracted from the probe data of the number of data, and determining the most upstream point as a traffic jam end. To detect traffic jam information.

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