JP4935698B2 - Traffic information processing apparatus, computer program, and traffic information processing method - Google Patents

Description

  The present invention relates to a technique for detecting whether or not a traffic jam occurs on a road and detecting a traffic jam section. In particular, the present invention relates to a traffic information processing apparatus, a computer program, and a traffic information processing method that specify the head position of a traffic jam section in detail and enable high accuracy of traffic information and signal control.

  Systems that detect the occurrence of traffic jams on roads and disclose traffic jam information in real time via a network have become widespread. In such a system, the road is divided into sections called links, and whether or not the section is a congestion section is determined based on whether or not the vehicle speed in each section is lower than a predetermined value.

In Patent Document 1, a vehicle, which is a mobile station equipped with a function of communicating information with the outside, acquires its position information using GPS (Global Positioning System), and transmits it to a management center which is a base station. A technique is disclosed in which the management center receives vehicle position information, calculates the speed of the vehicle, and determines that the section in which the vehicle is traveling is a traffic jam section when the speed is lower than the reference speed.
Japanese Patent Laid-Open No. 9-35189

  FIG. 8 is a schematic diagram showing an example of a traffic jam section determined for each link by the prior art. In the content example shown in the schematic diagram of FIG. 8, the road is divided into links based on the intersections and approximately the midpoints of the sections between the intersections, and is identified by codes “01” to “15”, respectively. Further, in the content example shown in the schematic diagram of FIG. 8, the links “03”, “05”, “06”, “07”, and “14” are determined as the traffic jam sections, and are separated from other links by hatching. It is shown separately. In particular, in the links “03” and “05”, the speed of each of the vehicles traveling in the link is lower than the reference speed, so that it is determined that the road is a traffic jam section.

  When the cause of traffic jams is broadly divided, it can be divided into waiting for traffic lights at intersections and capacity reduction due to accidents, parking, construction, etc. on single roads. In the configuration for determining whether or not each link is a traffic jam section, the traffic jam head position is specified as being approximately the link head position. However, the head position of each link is not always the head of a traffic jam. When the link “03” in FIG. 8 is a traffic jam section due to signal waiting, the head position of the traffic jam is near the stop line corresponding to the traffic light, while the link “07” is a traffic jam due to a capacity decrease in a single road section. In the case of a section, the head position of the traffic jam is a position where an event causing a capacity reduction occurs.

  Therefore, if the head position of the traffic jam can be specified in detail, it is possible to automatically determine which is the cause of the traffic jam. And when there is a traffic jam due to signal waiting, there is a possibility that the traffic flow can be made smooth by the control that extends the green time of the traffic signal.

  However, it is not possible to specify that the head position of the traffic jam is a stop line only by determining whether or not it is a traffic jam zone by the speed of the vehicle traveling in that zone, as in the prior art. The cause cannot be determined. When the head position of the traffic jam is a stop line corresponding to a traffic light in the direction of travel, the vehicle that can transmit speed information to the outside is not necessarily the head of the queue waiting for the signal, but at a position before the stop line It is thought that it is often stopped. In this case, it is considered that the point where the vehicle passes through the vicinity of the stop line, which is the head position of the real traffic jam, at a speed sufficiently higher than the reference speed and the vehicle speed satisfies the reference speed or more is still before the stop line. . Therefore, when the stop line is the head position of true traffic jam, the head position cannot be specified accurately.

  The present invention has been made in view of such circumstances, and by using the information of traffic lights, the head position of a traffic jam section on the road can be accurately identified, and the traffic information and signal control can be made highly accurate. It is an object to provide a traffic information processing apparatus, a computer program, and a traffic information processing method.

  A traffic information processing apparatus according to a first aspect of the present invention is a traffic information processing apparatus comprising means for acquiring traffic congestion information on a road, and specifying a head position of the traffic congestion section. The traffic information processing apparatus is traveling on a road section including the traffic congestion section. Calculation means for calculating a leading position candidate of a traffic jam section based on positions at a plurality of points in time of the vehicle, and a start wave required for a start wave to propagate to the vehicle from the position of the stop line corresponding to the traffic signal in the traveling direction of the vehicle Means for determining the propagation time and the elapsed time required for the vehicle to pass the candidate for the start position from the start of the green signal at the traffic light, and the start position of the traffic jam section based on the start wave propagation time and the elapsed time And a specifying means for specifying.

  In the traffic information processing apparatus according to the second aspect of the present invention, the specifying unit includes a determining unit that determines whether or not a difference between the starting wave propagation time and the elapsed time is equal to or less than a predetermined value. When it is determined that the value is less than or equal to the value, the stop line corresponding to the traffic signal is specified as the traffic jam head position.

  The traffic information processing apparatus according to the third invention is characterized in that, when the judging means judges that a predetermined value is exceeded, a traffic jam head position is specified based on the calculated head position candidate. .

  A traffic information processing apparatus according to a fourth aspect of the present invention comprises means for calculating a temporal change in acceleration at a plurality of points in time of the vehicle. When the determination means determines that the vehicle exceeds a predetermined value, the vehicle determines the head position candidate. A traffic jam head position is specified based on a temporal change in acceleration of the vehicle within a predetermined time before or after the passing time.

  In the traffic information processing apparatus according to a fifth aspect of the invention, the calculating means sets the position of the vehicle as a leading position candidate based on a time point when the average speed within the past predetermined time of the vehicle changes to a predetermined speed or more. It is characterized by being.

  According to a sixth aspect of the present invention, there is provided a computer program for causing a computer to acquire traffic congestion information on a road and to specify a head position of the traffic congestion section. A calculation means for calculating a leading position candidate of a traffic jam section based on the position of the vehicle, a start wave propagation time required for a start wave to propagate to the vehicle from the position of a stop line corresponding to a traffic light in the traveling direction of the vehicle, and Means for determining an elapsed time required from when the green signal starts at a traffic light until the vehicle passes the head position candidate, and specifying means for specifying a head position of a traffic jam section based on the starting wave propagation time and the elapsed time It is made to function as.

  A traffic information processing method according to a seventh aspect of the present invention is the traffic information processing method for acquiring traffic congestion information on a road and identifying the head position of the traffic congestion section. Locations of vehicles traveling on a road section including the traffic congestion section at a plurality of points in time Based on the start position candidate of the traffic jam section, the start wave propagation time required for the start wave to propagate to the vehicle from the position of the stop line corresponding to the traffic signal in the traveling direction of the vehicle, and the blue signal at the traffic light An elapsed time required from the start time until the vehicle passes the candidate for the start position is obtained, and the start position of the traffic jam section is specified based on the start wave propagation time and the elapsed time.

  In the first invention, the sixth invention, and the seventh invention, when there is a traffic jam, the head position candidate is calculated based on the location of the vehicle traveling in the traffic jam section and its surroundings at a plurality of points in time. The leading position candidate is a position where the vehicle can escape the traffic jam section and increase the speed, such as when the speed exceeds a predetermined speed or the distance between the vehicle ahead and the vehicle exceeds a predetermined value. It corresponds to. When the speed of the vehicle is used, it may be calculated from the positions at a plurality of times, or information on the speed at each time may be acquired. In a traffic jam section that causes signal waiting, the time at which the vehicle can increase speed is the time required for the start wave to propagate and reach the vehicle after the green signal is displayed on the traffic light. There should be a relationship between

  The starting wave here means that there is a time difference between the start of the first vehicle in the vehicle queue and the start of the rear vehicle, and the start of the vehicle starts from the first vehicle to the rear vehicle one after another. Is defined as a wave that propagates. In the present invention, the start wave propagation time required for the start wave to propagate from the stop line to the start position candidate where the vehicle can increase the speed, and the vehicle from the start point when the green signal is actually started The elapsed time until the point where the position candidate passes, that is, the speed can be increased, is obtained, and the leading position candidate is related to the control of the traffic light based on the relationship between the start wave propagation time and the elapsed time. It becomes possible to specify whether or not it has.

  In the second invention, the difference between the start wave propagation time required for the start wave to propagate from the stop line to the head position candidate and the elapsed time required for the vehicle to pass the head position candidate after the start of the green signal is When the values are almost equal to or less than the predetermined value, it is possible to determine that the start wave has propagated one after another from the beginning in response to the start of the green signal display on the traffic light, and that the vehicle has been started and the speed can be increased. is there. In this case, the head position of the traffic jam section is not the position where the speed can be increased, but the position of the stop line corresponding to the traffic light.

  In the third invention, the difference between the start wave propagation time required for the start wave to propagate from the stop line to the head position candidate and the elapsed time required for the vehicle to pass the head position candidate after the start of the green signal is If it is not possible to determine that the values coincide with each other, the relationship between the start of the green signal display on the traffic light and the possibility of increasing the speed is low, and the vehicle can increase the speed. Since there is a high possibility that the leading position candidate corresponding to the position and the position in the vicinity thereof are actually the leading position of the traffic jam section, the leading position is specified based on the leading position candidate.

  In the fourth aspect of the present invention, particularly when there is a high possibility that the leading position candidate corresponding to the position at which the vehicle can increase the speed and the position in the vicinity thereof are actually the leading position of the traffic jam section, the vehicle is removed from the traffic jam. Since acceleration is possible at this point, it can be estimated that the time change of acceleration, that is, jerk (jump) increases. Therefore, the position of the vehicle corresponding to the period in which the time change of the acceleration is large is specified as the head position of the traffic jam section.

  In the fifth invention, acceleration is possible at a point corresponding to the head of the traffic jam section, that is, a point out of the traffic jam, and it is estimated that the vehicle travels at a sufficient speed. Based on the point in time when the vehicle speed exceeds the predetermined speed, the leading position candidate of the vehicle position is calculated.

  In the case of the present invention, using traffic light information, traffic jams caused by waiting for traffic lights due to the time relationship between the start of blue display of traffic lights and the speed increase of vehicles traveling in the traffic jam section, and other traffic jams And the head position of the traffic jam section is accurately identified according to each. By accurately identifying the head position, the traffic information can be made highly accurate, and in the case of traffic jams caused by waiting for traffic lights, traffic can be controlled by extending the green signal of the traffic signal that causes the traffic. It is also possible to make the flow smooth.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.

(Embodiment 1)
FIG. 1 is a schematic diagram showing an outline of processing by the traffic information processing apparatus in the first embodiment. The traffic information processing apparatus 1 is installed at the roadside shown in FIG. 1 or at a remote traffic control center. The communication devices 2, 2,... Are installed on the roadside and can acquire information transmitted from the in-vehicle devices 3, 3 (see FIG. 2) having a positioning function using GPS (Global Positioning System). . The signal control devices 4, 4,... Control signal display of the connected traffic light 5 such as red light, yellow light, blue light, and blue arrow. The communication devices 2, 2,... And the signal control devices 4, 4,. As shown by the broken line in the schematic diagram of FIG. 1, the connection form may be a wired connection, or may be configured to be able to communicate wirelessly when the traffic information processing apparatus 1 is installed in a traffic control center. Good. VA, VB, and VC in FIG. 1 are vehicles equipped with an in-vehicle device 3 having a positioning function using GPS. 1, the on-vehicle devices 3, 3,..., Some communication devices 2, 2,... And the signal control devices 4, 4,.

  The communication devices 2, 2,... Have vehicle identification information (ID), position information, and speed transmitted at regular intervals (for example, every 100 milliseconds) from the in-vehicle device 3 mounted in each of the vehicles VA, VB, and VC. Information is received, and each received information is transmitted to the traffic information processing apparatus 1. The speed information is not transmitted from the in-vehicle device 3, and the traffic information processing device 1 may calculate the vehicle speed based on the position information. Further, the signal control devices 4, 4,... Control each color display of the traffic light 5 and transmit the start time information to the traffic information processing device 1 each time each color display is started.

  The traffic information processing apparatus 1 determines whether or not there is a traffic jam for each road section. The determination as to whether or not a traffic jam has occurred is based on the vehicle identification information, the position information, and the speed information transmitted via the communication devices 2, 2,..., For example, the past predetermined time (for example, 1 minute) of the vehicle VA. If the average speed is less than the reference speed (10 km / h (hours)), it may be determined that the traffic jam has occurred in the section corresponding to the predetermined time, the section in which the vehicle VA is traveling. Alternatively, it may be configured to acquire and determine VICS (registered trademark) information for each section (link) dividing the road. Moreover, it is good also as a structure which measures the occupation rate of a road with the vehicle sensor installed on the road, and determines whether the traffic congestion has generate | occur | produced based on the measured occupation rate.

  And when the vehicle which mounts the vehicle-mounted apparatus 3 is drive | working the traffic information processing apparatus 1 in Embodiment 1 in the area where it is determined that the traffic congestion has occurred, each information and signal transmitted from the said vehicle Using the information of the green signal start time transmitted from the control device 4, the head position of the traffic jam is specified. In order to specify the head position of the traffic jam, the traffic information processing apparatus 1 first determines a traffic jam head position candidate, and determines whether or not the traffic jam head position determined as a candidate is actually the head position. Judgment is made using the information of the green signal start time transmitted from.

  For example, as shown in the schematic diagram of FIG. 1, in a section where the vehicle VB is traveling, there is a traffic jam due to a decrease in capacity due to the presence of a stopped vehicle on a single road portion. The cause of the capacity reduction is lane reduction, merging, etc., in addition to a stopped vehicle such as an accident vehicle or a broken vehicle. In these cases, the point where the vehicle VB can increase the speed can be said to be a point where the traffic jam is actually removed. Therefore, by setting the point at which the vehicle can increase the speed as the traffic jam head position, the head position can be specified in more detail than when the head position of the traffic jam section is used as the head of each link.

  On the other hand, as shown in the schematic diagram of FIG. 1, in the section where the vehicle VA is traveling, there is a traffic jam due to signal waiting. In this case, it cannot be said that the point at which the vehicle is able to increase the speed has actually escaped the traffic jam. This is because the head of a traffic jam section caused by waiting for a signal is the position of a stop line corresponding to the traffic light 5 in the traveling direction of the vehicle VA. In this case, the time point at which the vehicle VA can start should almost coincide with the time point at which the start wave reaches the position of the vehicle VA in the queue starting from the vicinity of the stop line.

  Here, the starting wave is defined as follows. When there is no traffic jam ahead and the running vehicle stops and forms a queue, the first vehicle in the queue starts to start and the rear vehicle starts to start There will be a time difference. In this case, a state where the start start is successively propagated from the head vehicle to the rear vehicle is regarded as a wave and defined as a start wave.

  Further, as shown in the schematic diagram of FIG. 1, a traffic jam occurs even in a section where the vehicle VC is traveling. However, this traffic jam is caused by a traffic jam in a section ahead of the traffic light 5 immediately after the traveling direction of the vehicle VC (a section where the vehicle VB is traveling), and the head position of the traffic jam should not exist in the section. is there.

  In this way, by setting the point at which the vehicle can increase the speed as the traffic jam head position, the head position can be specified in more detail than the head position of the traffic jam section as the head of each link. If the head position is specified in the same way in all traffic jam sections regardless of the cause, it may be specified erroneously.

  Therefore, the traffic information processing apparatus 1 according to the first embodiment sets the vehicle position at the time when the vehicle traveling in the traffic jam section can increase the speed as a traffic jam head position candidate, and starts a green signal display. The head position of the traffic jam is specified according to whether or not there is a relationship between the timing at which the vehicle is driven and the timing at which the vehicle can increase the speed. There is no relationship between these timings in a traffic jam caused by a capacity drop in a single road. The vehicle VB can start later by starting each vehicle in order from the head vehicle in the queue formed starting from the point where the event causing the capacity reduction occurs. This is because it is not necessarily related to the green signal display on the traffic light 5 in the traveling direction of the vehicle VB. On the other hand, in a traffic jam caused by waiting for a signal, there should be a relationship between these timings. The vehicle VA can start later by starting each vehicle in order from the first vehicle in the queue starting from the stop line, and the timing at which the first vehicle starts is the timing when the green signal display of the traffic light 5 is started. That's why.

  Therefore, if there is a relationship between the timing at which the green signal display is started and the timing at which the vehicle can increase the speed, it can be determined that the signal waiting is the cause, The stop line corresponding to the traffic light 5 is specified as the head position of the traffic jam. On the other hand, if there is no relationship between the timing at which the green signal display is started and the timing at which the vehicle can increase the speed, it can be determined that the cause of the traffic jam is not waiting for the signal. The vehicle position at the time when the speed can be increased is identified as the head position of the traffic jam. Thus, it becomes possible to specify the head position of the traffic jam in more detail and accurately.

  Hereinafter, details of the configuration of the traffic information processing apparatus 1 for realizing the detailed and accurate specification of the head position of the traffic jam as described above will be described. FIG. 2 is a block diagram illustrating the internal configuration of the traffic information processing apparatus 1, the communication apparatus 2, the in-vehicle apparatus 3, and the signal control apparatus 4 according to the first embodiment.

  The in-vehicle device 3 is mounted on a vehicle and includes a control unit 30, a storage unit 31, a GPS reception unit 32, and a transmission unit 33. The control unit 30 controls each component. The storage unit 31 stores identification information (ID) for identifying the vehicle. The GPS receiving unit 32 has a function of receiving time information from a GPS (Global Positioning System) satellite.

  The control unit 30 of the in-vehicle device 3 calculates vehicle position information based on the time information received by the GPS receiving unit 32. Moreover, the control part 30 is comprised so that speed information may be acquired from the speed detection apparatus mounted in the vehicle. Then, the control unit 30 transmits the time information received by the GPS receiving unit 32, the position information calculated based on the time information, and the acquired speed information together with the vehicle identification information read from the storage unit 31 by the transmission unit 33. 2 to send. At this time, the position information calculation timing and transmission timing are set to a constant cycle every 100 milliseconds. The time information transmitted from the in-vehicle device 3 may not be the time information received by the GPS receiving unit 32. The in-vehicle device 3 is configured to include a time measuring unit that measures time at a predetermined frequency, measures an elapsed time from a predetermined reference time, and the control unit 30 acquires time information corresponding to the calculated position information from the time measuring unit. May be transmitted.

  The communication device 2 includes a control unit 20, a reception unit 21, and a transmission unit 22. The control unit 20 of the communication device 2 controls each component unit. The receiving unit 21 has a function of receiving vehicle identification information, time information, position information, and speed information transmitted from the in-vehicle device 3. The transmission unit 22 has a function of realizing communication with the traffic information processing apparatus 1. The control unit 20 transmits the vehicle identification information, time information, position information, and speed information received by the reception unit 21 to the traffic information processing apparatus 1 by the transmission unit 22.

  The signal control device 4 includes a control unit 40, a storage unit 41, a timer unit 42, an output unit 43, and a communication unit 44. The control unit 40 controls each component unit. The storage unit 41 stores the signal display start timing of each color such as a blue light, a yellow light, a red light, and a blue arrow of the traffic light 5. The timer 42 measures time with a predetermined frequency, and the controller 40 can acquire the time measured from the timer 42. Note that the time acquired by the time measuring unit 42 may be an absolute time or an elapsed time from a predetermined reference time, which is a time synchronized with the time information transmitted from the in-vehicle device 3, and It only needs to represent a comparable time. The timer unit 42 may have a GPS reception function and transmit time information based on the received time information. Thereby, it is possible to transmit the time information synchronized with the time information transmitted from the in-vehicle device 3. The output unit 43 is configured to output a control signal to the traffic light 5 according to an instruction from the control unit 40. Further, the communication unit 44 has a function of realizing communication with the traffic information processing apparatus 1, transmits information on a green signal start time described later, and transmits information on a signal switching instruction from the traffic information processing apparatus 1. In some cases, this is received.

  When the time acquired from the time measuring unit 42 matches the display start timing stored in the storage unit 41 or when the communication unit 44 receives a signal switching instruction, the control unit 40 of the signal control device 4 The output unit 43 outputs a control signal for starting the display of the color signal. Moreover, when the control part 40 outputs the control signal which starts a blue signal display, it transmits the information of a green signal start time to the traffic information processing apparatus 1 by the communication part 44. FIG.

  The traffic information processing apparatus 1 includes a control unit 10, a storage unit 11, a temporary storage area 12, and a reception unit 13. The storage unit 11 stores a control program 1P that causes the computer to function as the traffic information processing apparatus 1 according to the present invention. The temporary storage area 12 is used for temporarily storing information generated by the processing of the control unit 10. The receiving unit 13 has a function of realizing communication with the communication device 2 and the signal control device 4 and receives various information transmitted from the communication device 2 and the signal control device 4. The control unit 10 reads out the control program 1P from the storage unit 11 to the temporary storage area and executes it, thereby performing processing for identifying the head position of the traffic jam using various information received by the reception unit 13.

  Next, the process in which the control unit 10 of the traffic information processing apparatus 1 specifies the head position of the traffic jam will be described in detail with reference to a flowchart. FIG. 3 is a flowchart illustrating an example of a processing procedure in which the control unit 10 of the traffic information processing apparatus 1 according to the first exemplary embodiment identifies the head position of a traffic jam.

  The control unit 10 determines whether the receiving unit 13 has received vehicle identification information, time information, position information, and speed information from the communication device 2 (step S101). When the control unit 10 determines that the vehicle identification information, time information, position information, and speed information are not received from the communication device 2 (S101: NO), the control unit 10 receives the green signal start time information from the signal control device 4. 13 determines whether or not it has been received (step S102). If the control unit 10 determines that the green signal start time information has not been received (S102: NO), the control unit 10 returns the process to step S101. If the control unit 10 determines that the green signal start time information has been received (S102: YES), the control unit 10 stores the green signal start time indicated by the received information in the temporary storage area (step S103), and returns the process to step S101.

  When it is determined that the vehicle identification information, time information, position information, and speed information have been received from the communication device 2 (S101: YES), the control unit 10 stores the received information in the storage unit 11 or the temporary storage area. (Step S104). Then, the control unit 10 determines whether or not the road on which the vehicle specified by the identification information is traveling is a traffic jam section based on the positional information in the received information (step S105). Judgment as to whether or not it is a traffic jam section may be made based on traffic jam information such as VICS (registered trademark) information acquired from other devices, and the average speed of the vehicle within a predetermined past time is a reference. You may judge based on whether it is less than speed.

  When the control unit 10 determines that the road on which the vehicle specified by the identification information is traveling is not a traffic jam section (S105: NO), the process returns to step S101.

When the control unit 10 determines that the road on which the vehicle specified by the identification information is traveling is a traffic jam section (S105: YES), the time indicated by the time information based on the received time information, position information, and speed information. It calculates the average speed of the vehicle in the past predetermined time (e.g., 1 minute) U (t _i) from t _i, stored in the storage unit 11 or the temporary storage area 12 (step S106). For example, the average speed is calculated by averaging the speed indicated by the speed information received at each time point within the past one minute. However, since the speed information from the in-vehicle device 3 is not essential and may be calculated from the position information, the average speed may be calculated based on the position information one minute before and the position information received this time.

Then, the control unit 10 determines that the average speed U (t _i ) calculated in step S106 is equal to or greater than the threshold value VJ stored in the storage unit 11 in advance, and the average speed U (t _i calculated and stored last time _{). −1} ) is less than the threshold value VJ (average speed U (t _i ) ≧ VJ and previous average speed U (t _i-1 ) <VJ) are determined (step S107). Note that t _i-1 is the time indicated by the previously received time information.

The control unit 10 determines whether the average speed U (t _i ) calculated in step S106 is less than the threshold value VJ stored in the storage unit 11 in advance, or the average speed U (t _i− calculated and stored last time). _{If 1} ) is equal to or greater than the threshold value VJ (S107: NO), the process returns to step S101, and then waits until each information transmitted from the communication device 2 is received.

Control unit 10, the average speed U calculated in step S106 (t _i) is, and the threshold value VJ or more that is stored in advance in the storage unit 11, the average speed and are calculated and stored previous U (t _{i- When} it is determined that ₁ ) is less than the threshold value VJ (S107: YES), the position of the vehicle at the time point t _i is determined as a traffic jam leading position candidate (step S108).

Next, the control unit 10 has a relationship between the start point of the green signal display and the time point t _i when the vehicle passes the traffic jam leading position candidate determined in step S108, that is, the timing at which the average speed U (t _i ) is increased. It is determined by the following formula (1) (step S109).

In addition, each variable in Formula (1) is the following numerical values.
L: distance between vehicle position information X (t _i ) at time t _i and stop line position information Y corresponding to the downstream traffic light 5;
Lj: average distance traveled from the start of the vehicle until the average speed becomes equal to or greater than the threshold value VJ
VS: preset starting wave speed,
t _i : Time indicated by the received time information,
tj: average required time from the start of starting until the average speed is equal to or higher than the threshold value VJ;
TS: Time indicated by the received green light start time information,
e: judgment value set in advance

Note that the starting wave velocity represented by VS in the equation (1) is a velocity at which the starting wave propagates. The starting wave velocity may be a value calculated in advance from past statistics or a value calculated by simulation. When the vehicle starts in response to the start of green signal display, the time required for the vehicle to start starting from the green signal start time and the start wave propagation required for the start wave to propagate from the stop line to the vehicle Time should almost match. At this time, it is presumed that the time point tj before the time point t _i when the vehicle speed becomes equal to or higher than the threshold value VJ is the time when the vehicle starts, and the position X (t _i ) at the time point t _i when the speed becomes equal to or higher than the threshold value VJ. This is because it is presumed that the position before Lj from the distance L from the previous stop line is the position where the vehicle started (accelerated). Therefore, when the time required for the vehicle to start starting and the starting wave propagation time substantially coincide with each other, the value on the left side of equation (1) should be sufficiently small and zero, and according to equation (1) It can be determined whether or not there is a relationship. The average required time tj from the start of starting until the speed becomes equal to or higher than VJ and the average distance Lj that travels during the required time tj are statistically obtained in advance by simulation or the like. In addition, when the vehicle is waiting for a signal on the stop line at the head of the train, the position X (t _i ) where the average speed U (t _i ) is equal to or greater than the threshold value VJ is ahead of the stop line. , L in the left side of equation (1) is calculated as a negative value. Further, the consideration of the required time tj and the distance Lj that travels between the required time tj is included in e on the right side of Equation (1),
| L / VS− (t _i −TS) | <e (2)
It is good also as a structure judged based on.

  When the control unit 10 determines that there is a relationship in step S109 (S109: YES), the control unit 10 specifies the position of the stop line corresponding to the traffic light 5 instead of the head position candidate determined in step S108 as the traffic jam head position. (Step S110), and the process ends. In this case, the speed increase is due to the departure from the queue for the traffic light 5, and therefore it can be determined that the cause of the traffic congestion is waiting for a signal.

  On the other hand, if the control unit 10 determines that there is no relationship in step S109 (S109: NO), the head position candidate determined in step S108 is identified as the head position of the traffic jam (step S111), and the process ends. . In this case, the speed increase is not due to the departure from the queue corresponding to the traffic light 5, but because it can be determined that the vehicle has passed a place where the cause of the traffic congestion has occurred.

  Next, processing by the traffic information processing apparatus 1 shown in the flowchart of FIG. 3 will be described by applying a specific example. 4 to 6 are schematic views for explaining the head position specified by the traffic information processing apparatus 1 according to the first embodiment.

  The schematic diagram of FIG. 4 shows the state of a congested vehicle train in a time series when there is a traffic jam caused by waiting for a signal. In the schematic diagram of FIG. 4, the vehicle train at each point in time from when the blue light is started by the corresponding traffic light 5 (not shown) is shown as time goes downward. Y in FIG. 4 indicates the position of the stop line, and in the vehicle train shown in the schematic diagram of FIG. 4, the vehicle VA shown to be distinguished from other vehicles by hatching includes the in-vehicle device 3. It is a vehicle.

  As shown in the flowchart of FIG. 3, the traffic information processing apparatus 1 receives the identification information, time information, position information, and speed information of the vehicle VA from the in-vehicle device 3 of the vehicle VA every 100 milliseconds via the communication device 2. Then, the data is stored in the storage unit 11 or the temporary storage area 12, and the process is executed. In addition, the traffic information processing apparatus 1 has received the information of the green light start time TS and stores it in the temporary storage area 12.

  At the time of the green signal start time TS, only the leading vehicle stopped near the stop line is starting. And, from the fact that the average speed of the vehicle VA within the past one minute is 10 (km / h) or less, or the occupation rate measured by the VICS (registered trademark) information or the vehicle detector, the section where the vehicle VA is traveling is There is a high possibility that the traffic information processing apparatus 1 determines that the section is a traffic jam. Therefore, the traffic information processing apparatus 1 calculates and stores the average speed of the vehicle VA at each time point within the past one minute. At the time of the green signal start time TS, the vehicle VA stops without starting, and the average speed U (TS) calculated by the traffic information processing apparatus 1 does not exceed the threshold value VJ, and the leading position candidate of the traffic jam is determined. Without any further processing, the process waits until the identification information, time information, position information, and speed information of the vehicle VA transmitted from the in-vehicle device 3 are received next. The threshold value VJ at this time is 10 (km / h).

  The start wave propagates at a speed of VS (m / s (seconds)) with respect to the start of the green signal. Specifically, it is about 5.5 (m / s). At the time one second after the green signal start time TS, the second vehicle from the head has started to start. At the time 2 seconds after the green signal start time TS, the third vehicle from the head has started to start. Similarly, the vehicle VA corresponding to the sixth vehicle from the head remains stopped until 5 seconds after the green signal start time TS, and the average speed does not exceed the threshold value VJ.

  At the time 6 seconds after the green light start time TS, the vehicle VA that has stopped 32.5 m before the stop line has started to start (starting wave propagation time = 5.9 seconds = 32.5 m / 5). .5 (m / s)). However, at this time, the average speed U (TS + 6) calculated by the control unit 10 of the traffic information processing apparatus 1 is an average speed for each time point within the past one minute, and thus does not exceed the threshold VJ and has stopped until then. Is almost equal to zero. Thereafter, it is assumed that the average speed U (TS + 22) becomes 10 (km / h) at the time point 22 seconds after the green light start time TS, and satisfies the threshold VJ or more. The control unit 10 of the traffic information processing apparatus 1 temporarily determines the position X (TS + 22) of the vehicle VA at a time point 22 seconds after the green signal start time TS as a traffic jam leading position candidate.

Then, the control unit 10 of the traffic information processing apparatus 1 determines whether or not the time (t _i = TS + 22) when the speed of the vehicle VA becomes equal to or higher than the threshold value VJ has a relationship with the start time of the green light. . The judgment value e is 3 (s (seconds)).

Assuming that the position X (TS + 22) at the time point (t _i = TS + 22) is 133 m ahead of the stop line position Y, the left side of the equation (1) is calculated as the following equation (3).

In Equation (1), it is assumed that the required time tj required for the average speed in one minute from the stop state to be equal to or higher than the threshold value 10 (km / h) is set to 16.1 seconds. The required time tj is obtained as follows. Assuming that the acceleration is 1.7 (m / s ² ), it takes 8.2 s to advance to 57 m from the stop state until the speed reaches 50 (km / h) or more. Considering that the vehicle was stopped, the average speed per minute must be 166.7 m per minute to reach 10 (km / h), so the remaining 109.7 m is 50 (km / h). When traveling, the time required for this is 7.9 s. Therefore, the total time (8.2 s + 7.9 s) is obtained as the required time tj. In this case, since the distance traveled during the required time tj is 166.7 m, Lj is obtained as 166.7 m.

  Since the left side satisfies the condition of the judgment value e = 3 or less, it is determined that the average speed of the vehicle VA is equal to or higher than the threshold value VJ is related to the start of the green light, and that it is a traffic jam causing the signal waiting, The stop line corresponding to the traffic light 5 is identified as the traffic jam head position. In this way, the exact start position of the traffic jam is specified.

  As a result, as shown in the schematic diagram of FIG. 1, the cause of the traffic jam is determined as waiting for the signal based on the information from the vehicle VA that is in the traffic jam section causing the signal waiting, and the head position of the traffic jam is set as the stop line. Can be identified. In this case, the information about the traffic jam situation can be made highly accurate. In addition, the control of the traffic light 5 causing the traffic jam in the traveling direction of the vehicle VA is extended to increase the signal control such as increasing the possibility of eliminating the traffic jam involving the vehicle VA. It is possible to improve the accuracy and smooth the traffic flow.

  The schematic diagram of FIG. 5 shows the state of a congested vehicle train in a time series when there is a congested traffic due to a decrease in capacity due to the presence of a stopped vehicle such as an accident vehicle on a single road. ing. The configuration of the schematic diagram of FIG. 5 is the same as the schematic diagram of FIG. In the schematic diagram of FIG. 5 as well, the vehicle train at each point in time from when the blue light is started by the corresponding traffic signal 5 (not shown) is shown as time goes downward. In addition, Y in FIG. 5 indicates the position of the stop line, and in the vehicle train shown in the schematic diagram of FIG. Vehicle.

  As shown in the flowchart of FIG. 3, the traffic information processing device 1 receives the vehicle VB identification information, time information, position information, and speed information every 100 milliseconds from the in-vehicle device 3 of the vehicle VB via the communication device 2. Receive and execute processing. In the traffic information processing apparatus 1, information on the green signal start time TS is received and stored in the temporary storage area 12.

  At the time of the green signal start time TS, the leading vehicle stopped near the stop line is starting. The vehicle VB is in a slow speed state (10 km / h or less) due to the presence of a stopped vehicle in front, and the average speed of the vehicle VB within the past one minute is 10 (km / h) or less, or VICS (registered trademark). ) From the information or the occupation rate measured by the vehicle detector, it is highly likely that the traffic information processing apparatus 1 determines that the section in which the vehicle VB is traveling is a traffic jam section. Therefore, the traffic information processing apparatus 1 calculates and stores an average of the speed of the vehicle VB at each time point within the past one minute. At the time of the green signal start time TS, it is estimated that the vehicle VB cannot be accelerated and is traveling at less than 10 (km / h), and the average speed U (TS) calculated by the traffic information processing apparatus 1 is equal to or greater than the threshold value VJ. The process waits until the next vehicle VB identification information, time information, position information, and speed information transmitted from the in-vehicle device 3 is received without determining the leading position candidate of the traffic jam. .

  The second vehicle from the beginning starts at the time 1 second after the green signal start time TS, and the third vehicle starts at the time 2 seconds later. The vehicle VB cannot be accelerated due to the presence of the stopped vehicle even at a point 17 seconds after the green signal start time TS, and the average speed U (TS + 17) is still calculated to be less than 10 (km / h).

  At a time point 18 seconds after the green signal start time TS, the vehicle in front of the vehicle VB has overtaken the stopped vehicle and started accelerating, so that the vehicle VB can also be accelerated. However, since the average speed calculated by the control unit 10 of the traffic information processing apparatus 1 at this time is an average speed for each time point within the past one minute, the average speed does not exceed the threshold value VJ at this time point. Thereafter, it is assumed that the average speed U (TS + 21) is 10.2 (km / h) at a time point 21 seconds after the green signal start time TS, and satisfies the threshold VJ or more. Therefore, the average speed is equal to or higher than the threshold value VJ (= 10 (km / h)) from the time point 20 seconds after the green signal start time TS to the time point 21 seconds later, and the previously calculated average speed is the threshold value VJ. There should be a point in time that is less than. For example, it is assumed that this condition is satisfied 20.8 seconds after the green light start time TS. The control unit 10 of the traffic information processing apparatus 1 temporarily determines the position X (TS + 20.8) of the vehicle VB at the time 20.8 seconds after the green signal start time TS as a traffic jam leading position candidate.

Then, the control unit 10 of the traffic information processing apparatus 1 determines whether or not the point in time (t _i = TS + 20.8) when the speed of the vehicle VB becomes equal to or higher than the threshold value VJ has a relationship with the start of the green light. To do.

Assuming that the position X (TS + 20.8) at the time point (t _i = TS + 20.8) is 11.5 m before the stop line position Y, the left side of the expression (1) is as shown in the following expression (4): Calculated.

  Since the left side does not satisfy the condition of the judgment value e = 3 or less, the fact that the average speed of the vehicle VB is equal to or higher than the threshold value VJ is not related to the start of the green light and is judged not to be a traffic jam caused by waiting for a signal. Here, the traffic jam head position candidate that is temporarily determined, and the position X (TS + 20.8) of the vehicle VB at the time point (TS + 20.8) in the schematic diagram of FIG. 5 is almost specified as the traffic jam head position. In this way, it is possible to accurately identify the head position of the traffic jam by determining the cause of the traffic jam.

  As a result, as shown in the schematic diagram of FIG. 1, the cause of the traffic congestion is determined as the capacity decrease by the information from the vehicle VB in the traffic congestion section that causes the capacity decrease due to the presence of the stopped vehicle, and the head of the traffic congestion The position can be specified, and the information on the traffic jam situation can be made highly accurate. Further, in this case, the traffic condition information can be detailed without a person confirming and notifying the presence or absence of a stopped vehicle such as an accident vehicle or a broken vehicle. In addition, it is also possible to determine that the cause of traffic congestion is due to lane reduction or merging if it corresponds to a lane decreasing point or merging point with reference to map information near the point specified as the head position of the traffic jam . In this case, it is possible to determine that the traffic jam cannot be resolved even if the green time of the traffic light 5 in the traveling direction of the vehicle VB is extended. Therefore, useless signal control can be avoided.

  The schematic diagram of FIG. 6 shows the state of a congested vehicle train in a time series when there is a traffic jam caused by an event downstream. The configuration of the schematic diagram of FIG. 6 is the same as that of the schematic diagram of FIG. In the schematic diagram of FIG. 6 as well, the vehicle train at each point in time from when the blue light is started by the corresponding traffic signal 5 (not shown) as time progresses downward. In addition, Y in FIG. 6 indicates the position of the stop line, and in the vehicle train shown in the schematic diagram of FIG. Vehicle.

  As shown in the flowchart of FIG. 3, the traffic information processing device 1 receives the vehicle VB identification information, time information, position information, and speed information every 100 milliseconds from the in-vehicle device 3 of the vehicle VB via the communication device 2. Receive and execute processing. In the traffic information processing apparatus 1, information on the green signal start time TS is received and stored in the temporary storage area 12.

  In the case of the example shown in the schematic diagram of FIG. 6, each vehicle cannot start even if the traffic light 5 corresponding to the stop line indicated by Y indicates a green signal because the traffic is still further downstream. At the time, only the first vehicle in the train is starting. The vehicle VC remains stopped because each vehicle ahead cannot start, and the speed of the vehicle VC within the past minute is 10 (km / h) or VICS (registered trademark) information or a vehicle detector. From the measured occupancy rate, it is highly likely that the section in which the vehicle VC is traveling in the traffic information processing apparatus 1 is determined to be a traffic jam section. Therefore, the traffic information processing apparatus 1 calculates and stores the average speed of the vehicle VC at each time point within the past one minute. Since the vehicle VC cannot start and stops at the time of the green signal start time TS, the average speed U (TS) calculated by the traffic information processing apparatus 1 is equal to or higher than the threshold value VJ (= 10 (km / h)). First, the process waits until the next vehicle VC identification information, time information, position information, and speed information are transmitted from the in-vehicle device 3 without determining the leading position candidate of the traffic jam.

  In the case of the example shown in the schematic diagram of FIG. 6, each vehicle starts after 4, 5, 6,... Seconds after the green signal start time TS while the traffic light 5 indicates a green signal, and even 21 seconds have passed. Therefore, it is considered that the average speed of the vehicle VC calculated by the traffic information processing apparatus 1 within the past one minute does not exceed the threshold value VJ until the vehicle VC passes through a point that becomes a bottleneck of the downstream traffic jam. Therefore, the traffic information processing apparatus 1 does not perform the processing after step S107 in the processing procedure shown in the flowchart of FIG. 3, and the head position is not specified in the traffic jam section. In fact, there should be no traffic jam head in the section, and there should be a traffic jam factor downstream. As described above, when the traffic information processing apparatus 1 executes the processing procedure shown in the flowchart of FIG. 3, the possibility that the leading position of the traffic jam is erroneously specified is also reduced.

  As a result, as shown in the schematic diagram of FIG. 1, the cause of the traffic jam is not determined based on the information from the vehicle VC in the traffic jam section, and the stop line ahead of the vehicle VC is specified as the head position of the traffic jam. There is no. The head position of the traffic jam section is identified and identified as being caused by a capacity drop in the downstream bottleneck, that is, in front of the vehicle VB. Even when the vehicle VB is not equipped with the in-vehicle device 3, the head position of the traffic jam is specified again when the vehicle VC is positioned behind the stopped vehicle. Thus, the head position of the traffic jam section can be specified with high accuracy, and the information about the traffic jam status can be made highly accurate.

(Embodiment 2)
In the first embodiment, as shown in the flowchart of FIG. 3, there is a relationship between the start of signal display in the process of specifying the head position and the increase of the average speed at the time when the vehicle passes the traffic jam head position candidate. When it is determined that the first position candidate is not included, the determined first position candidate is specified as the first position. In the second embodiment, when it is determined that there is no relationship, it is in the vicinity of the time point corresponding to the determined leading position candidate, and the time change of acceleration (jerk acceleration, jerk) becomes maximum. The position of the vehicle at that time is specified as the head position of the traffic jam. As a result, the head position of the traffic jam can be specified with higher accuracy.

  The traffic information processing apparatus 1, the communication apparatus 2, the in-vehicle apparatus 3, the signal control apparatus 4, and the traffic light 5 according to the second embodiment are other than a part of the processing for specifying the head position of the traffic jam by the control unit 10 of the traffic information processing apparatus 1. The configuration is the same as in the first embodiment. Hereinafter, the same reference numerals as those in the first embodiment are given, and the process for identifying the head position of the traffic jam will be described.

  FIG. 7 is a flowchart illustrating another example of a processing procedure in which the control unit 10 of the traffic information processing device 1 according to the second exemplary embodiment identifies the head position of a traffic jam. Of the processing procedures shown in the flowchart of FIG. 7, the steps common to the processing procedure shown in the flowchart of FIG. 3 are assigned the same step numbers, and detailed description thereof is omitted.

When the control unit 10 determines that the road on which the vehicle specified by the identification information is traveling is a traffic jam section (S105: YES), the time indicated by the time information based on the received time information, position information, and speed information. calculating with obtaining the average speed U (t _i) at t _i, the time t velocity V (t _i) at _i (speed information itself) from the acceleration a (t _i), the time variation B of the acceleration a (t _i) And memorize it (step S21). The acceleration A (t _i ) is A (t _i ) = {V (t _i ) −V (t _i−1 )} / (t _i −t _i−1 ), and acceleration time change B (t _i ) Is calculated by B (t _i ) = {A (t _i ) −A (t _i−1 )} / (t _i −t _i−1 ).

Then, the control unit 10 has a relationship between the start of the green signal display in step S109 and the increase of the average speed U (t _i ) at the time point t _i when the vehicle passes the traffic jam leading position candidate determined in step S108. Whether or not it is determined is determined by equation (1) (S109). When the control unit 10 determines that there is no relationship (S109: NO), the acceleration time change B (t ₁ ), B (t ₂ ),..., B (t _i ), the acceleration time change B (t _j ) that is maximum within the past one minute is specified, and the position X (t _j ) at that time t _j is specified as the congestion start position (step S22). The process ends. Although identifies becomes maximum acceleration time variation B (t _j) at step S22, it may be the second largest time variation B (t _j). In addition, the position X (t _j ) at the time point t _j at which the time change B (t _j ) of acceleration is the maximum is not limited, and a point around 1 to several meters from X (t _j ) is specified as the head position. May be.

  This makes it possible to specify the traffic jam head position with higher accuracy when the traffic jam head position is not a stop line. In the first embodiment, with respect to the example shown in the schematic diagram of FIG. 5, the position at the time 20.8 seconds after the green signal start time TS is specified as the traffic jam head position. On the other hand, in the second embodiment, the point at which the vehicle VC starts accelerating around the position specified as the congestion start position by the method in the first embodiment by the specifying process in step S22 described above is the traffic jam. It is specified as the head position.

  At the head position of the traffic jam, it can be estimated that the speed can be increased relatively rapidly because the factor that blocks the speed increase is eliminated. Therefore, it is possible to specify the head position more accurately by specifying the position of the vehicle at the time when the time change of the acceleration is maximum as the head position of the traffic jam. In this case, since the position at the time when the time change of the acceleration is maximum is specified as the head position of the traffic jam, not the position at the time when the threshold VJ changes to the threshold value VJ or more, the traffic jam head position is not affected by the threshold value VJ. Can be specified.

  In the first and second embodiments, the determination of the congestion start position candidate is performed in the procedure of the process for specifying the congestion start position by the control unit 10 of the traffic information processing apparatus 1 shown in the flowcharts of FIGS. 3 and 7. The position at the time point when the average speed within the past one minute is equal to or higher than the threshold value VJ is determined as the head position candidate. However, the present invention is not limited to this, and a point where it is estimated that the vehicle has passed the leading position of the traffic jam, that is, a point where the speed can be increased can be determined by another method. You may calculate as a position candidate. As another method, for example, the process in step S107 may be replaced with a determination process as to whether or not the distance between the vehicle and the vehicle ahead is a predetermined value or more.

  The disclosed embodiments should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

3 is a schematic diagram illustrating an outline of processing by the traffic information processing apparatus in Embodiment 1. FIG. 2 is a block diagram illustrating an internal configuration of a traffic information processing device, a communication device, an in-vehicle device, and a signal control device according to Embodiment 1. FIG. 6 is a flowchart illustrating an example of a processing procedure in which the control unit of the traffic information processing device according to the first exemplary embodiment specifies the head position of a traffic jam. 6 is a schematic diagram for explaining a head position specified by the traffic information processing apparatus according to Embodiment 1. FIG. 6 is a schematic diagram for explaining a head position specified by the traffic information processing apparatus according to Embodiment 1. FIG. 6 is a schematic diagram for explaining a head position specified by the traffic information processing apparatus according to Embodiment 1. FIG. 12 is a flowchart illustrating another example of a processing procedure in which the control unit of the traffic information processing device according to the second exemplary embodiment identifies the head position of a traffic jam. It is a schematic diagram which shows the example of the traffic congestion area determined for every link by the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traffic information processing apparatus 10 Control part 1P Control program 5 Traffic light

Claims (7)

In the traffic information processing apparatus provided with a means for acquiring road traffic jam information and adapted to identify the head position of the traffic jam section,
A calculation means for calculating a head position candidate of a traffic jam section based on positions at a plurality of times of a vehicle traveling on a road section including the traffic jam section;
The start wave propagation time required for the start wave to propagate to the vehicle from the position of the stop line corresponding to the traffic signal in the traveling direction of the vehicle, and the vehicle passes the leading position candidate from the start of the blue signal at the signal A means of determining the elapsed time required to
A traffic information processing apparatus comprising: a specifying unit that specifies a head position of a traffic jam section based on the starting wave propagation time and the elapsed time. The specifying means is:
A determination means for determining whether a difference between the starting wave propagation time and the elapsed time is a predetermined value or less;
The traffic information processing apparatus according to claim 1, wherein when the determination unit determines that the value is equal to or less than a predetermined value, the stop line corresponding to the traffic light is specified as a congestion start position. 2. The traffic information processing apparatus according to claim 1, wherein when the determination unit determines that the value exceeds a predetermined value, a traffic jam head position is specified based on the calculated head position candidate. Means for calculating the time change of acceleration at a plurality of points in time of the vehicle;
When it is determined that the determination means exceeds a predetermined value,
The traffic jam head position is specified based on a temporal change in acceleration of the vehicle within a predetermined time before or after the vehicle passes the head position candidate. Traffic information processing equipment. 5. The calculation means is configured such that the position of the vehicle is set as a leading position candidate based on a time point when the average speed within the past predetermined time of the vehicle changes to a predetermined speed or more. The traffic information processing apparatus according to any one of the above. In a computer program that causes a computer to acquire traffic congestion information on a road and identify the start position of a traffic congestion section,
Computer
A calculation means for calculating a head position candidate of a traffic jam section based on positions at a plurality of times of a vehicle traveling on a road section including the traffic jam section;
The start wave propagation time required for the start wave to propagate to the vehicle from the position of the stop line corresponding to the traffic signal in the traveling direction of the vehicle, and the vehicle passes the leading position candidate from the start of the blue signal at the signal A means for determining the elapsed time required to
A computer program that functions as specifying means for specifying a head position of a traffic jam section based on the starting wave propagation time and elapsed time. In the traffic information processing method of acquiring traffic congestion information on the road and identifying the head position of the traffic congestion section,
Based on the position of the vehicle running on the road section including the traffic jam section at multiple points in time, the head position candidate of the traffic jam section is calculated,
The start wave propagation time required for the start wave to propagate to the vehicle from the position of the stop line corresponding to the traffic signal in the traveling direction of the vehicle, and the vehicle passes the leading position candidate from the start of the blue signal at the signal Find the elapsed time required to
A traffic information processing method characterized by identifying a head position of a traffic jam section based on the starting wave propagation time and the elapsed time.

Images