Traffic flow control device, traffic flow control method, and program

Abstract

To provide a technique for efficiently controlling a traffic flow on a road.SOLUTION: A traffic flow control device includes: a traffic density calculation part for calculating a traffic density in respective sections based on a statistic amount of at least a vehicle speed in each one of the sections on a road; a determination part for performing a simulation of a change of the traffic density in each section for each one of a plurality of speed control patterns based on the traffic density and the plurality of speed control patterns in each section, and determining the speed control pattern, which is based on a performance result of the simulation and where a statistic amount of at least a vehicle acceleration is the smallest, as a determination pattern; and a transmission control part for controlling transmission of speed control information corresponding to the determination pattern.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a traffic flow control device, a traffic flow control method, and a program.

Background Art

[0002] In recent years, various technologies have been known as technologies for controlling traffic flow on roads.

[0003] For example, Patent Document 1 discloses that a roadside unit transmits prediction information representing the probability of the presence of a moving object to an automatic driving device mounted on a vehicle (see paragraph 0026 of the same document). Further, Patent Document 1 discloses setting a target acceleration at each time so as to reduce the probability of a vehicle colliding with a moving object (see paragraph 0071 of the same document). Furthermore, Patent Document 1 discloses calculating, as one of cost calculations, the sum of the absolute values of the target accelerations of a vehicle at each time during the period in which a travel pattern is set (see paragraph 0077 of the same document).

[0004] Patent Document 2 discloses that a target speed is set in advance on a travel route, and the travel speed of a vehicle is automatically controlled to follow the target speed (see, for example, paragraph 0015 of the same document). Further, Patent Document 2 discloses that the target speed set on the travel route may be changed when a sudden event such as construction or an accident occurs in a section of the travel route (see paragraph 0025 of the same document).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, it would be desirable to provide techniques that would allow for more efficient control of traffic flow on roads. [Means for solving the problem]

[0007] In order to solve the above problem, according to one aspect of the present invention, a traffic density calculation unit calculates a traffic density in each section on a road based on at least a statistical quantity of vehicle speed in the section, and a traffic density calculation unit executes a simulation of a change in traffic density in each section for each of a plurality of speed control patterns based on the traffic density in each section and a plurality of speed control patterns. As a result, for each of the plurality of speed control patterns, the traffic density at a later time in each of the sections is obtained as the execution result of the simulation. A traffic flow control device is provided, which includes a determination unit that determines, as a determination pattern, a speed control pattern that has the smallest statistical quantity of at least vehicle acceleration based on the results of executing the simulation, and a transmission control unit that controls the transmission of speed control information according to the determination pattern.

[0008] Each of the plurality of speed control patterns may be constituted by a combination of a control range on the road in which the vehicle speed is controlled to a predetermined control speed in the simulation and the control speed.

[0009] The determination unit may determine the control range based on a position of a congested flow section where the statistics of the vehicle speed is equal to or lower than a threshold, or a congested flow section where the traffic density is equal to or higher than a threshold.

[0010] The determination unit may execute the simulation when a length of the congested flow section or the congested flow section is equal to or longer than a predetermined length.

[0011] The traffic density calculation unit may calculate the traffic density in the first section on the road based on a statistical amount of vehicle speed in the first section and a relational expression indicating a relationship between the traffic density and the vehicle speed.

[0012] The first section may be a section in which a statistical quantity of vehicle speed is equal to or less than a threshold value.

[0013] The traffic flow control device may include a parameter creation unit that creates parameters for the relational expression through machine learning.

[0014] The traffic flow control device may include a traffic volume calculation unit that calculates the traffic volume at a specified measurement point on the road based on detection results of vehicles traveling at the specified measurement point, and the traffic density calculation unit may calculate the traffic volume in the second section based on the traffic volume at the specified measurement point and statistics of vehicle speeds for each section from the specified measurement point to a second section on the road, and calculate the traffic density in the second section based on the traffic volume in the second section and the statistics of vehicle speeds in the second section.

[0015] The second section may be a section in which a vehicle speed statistic exceeds a threshold value.

[0016] The determination unit may determine, as the determination pattern, a speed control pattern that has the smallest statistics of vehicle acceleration and vehicle deceleration based on a result of execution of the simulation.

[0017] The transmission control unit may control transmission of the speed control information to a first vehicle-mounted device.

[0018] The first vehicle-mounted device may include a receiving unit that receives the speed control information, and a speed control unit that controls an ACC module or an autonomous driving module so that the vehicle travels at a speed corresponding to the speed control information received by the receiving unit.

[0019] The first vehicle-mounted device may include a receiving unit that receives the speed control information, and a driver presentation unit that presents presentation information based on the reception of the speed control information by the receiving unit to a driver of the vehicle.

[0020] The first in-vehicle device may include a receiving unit that receives the speed control information, and a following vehicle presentation unit that presents presentation information based on the reception of the speed control information by the receiving unit to the driver of a following vehicle.

[0021] The transmission control unit controls the transmission of the speed control information to the first in-vehicle device by the first transmission unit, and outputs the speed control information to a second transmission unit different from the first transmission unit. The second transmission unit converts the protocol of the speed control information according to a second communication protocol different from the first communication protocol used by the first in-vehicle device, and transmits the speed control information after the protocol conversion to a second in-vehicle device that uses the second communication protocol.

[0022] The transmission control unit may control the transmission of the speed control information to an electric signboard installed on the road.

[0023] According to another aspect of the present invention, calculating a traffic density in each section based on at least a statistical amount of vehicle speeds in each section on a road, and performing a simulation of a change in traffic density in each section for each of the plurality of speed control patterns based on the traffic density in each section and the plurality of speed control patterns As a result, for each of the plurality of speed control patterns, the traffic density at a later time in each of the sections is obtained as the execution result of the simulation. determining, as a determination pattern, a speed control pattern in which at least a statistical amount of vehicle acceleration based on the execution result of the simulation is the smallest, and controlling the transmission of speed control information according to the determination pattern. A traffic flow control method is provided.

[0024] According to another aspect of the present invention, a computer is configured to calculate a traffic density in each section based on at least a statistical amount of vehicle speeds in each section on a road, and perform a simulation of a change in traffic density in each section for each of the plurality of speed control patterns based on the traffic density in each section and the plurality of speed control patterns As a result, for each of the plurality of speed control patterns, the traffic density at a later time in each of the sections is obtained as the execution result of the simulation. A program is provided that functions as a traffic flow control device, comprising a determination unit that determines as a determination pattern a speed control pattern that has at least the smallest statistical quantity of vehicle acceleration based on the results of executing the simulation, and a transmission control unit that controls the transmission of speed control information according to the determination pattern. Effect of the Invention

[0025] As described above, according to the present invention, a technique is provided that enables more efficient control of traffic flow on roads. [Brief description of the drawings]

[0026]

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[0027] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals, and duplicated explanations will be omitted.

[0028] In addition, in this specification and drawings, multiple components having substantially the same functional configuration may be distinguished by adding different numbers after the same reference symbol. However, if there is no particular need to distinguish between multiple components having substantially the same functional configuration, only the same reference symbol is used. Furthermore, similar components in different embodiments may be distinguished by adding different alphabets after the same reference symbol. However, if there is no particular need to distinguish between similar components in different embodiments, only the same reference symbol is used.

[0029] (0. Overview) First, an overview of the embodiment of the present invention will be described.

[0030] In recent years, various methods have been known for controlling traffic flow on roads, such as the technique disclosed in Patent Document 1 and the technique disclosed in Patent Document 2, as described above.

[0031] The technology disclosed in Patent Document 1 is expected to enable efficient control of a single vehicle, and to have the effect of, for example, reducing unnecessary acceleration and deceleration. However, when there are multiple vehicles on the road, the influence of the vehicle in front extends to the vehicle behind, and therefore, the technology disclosed in Patent Document 1 is highly unlikely to be able to control each vehicle in an integrated manner.

[0032] For example, the technique disclosed in Patent Document 1 cannot avoid the so-called accordion phenomenon, which occurs when vehicles accelerate and decelerate repeatedly in a congested traffic flow.

[0033] Figure 1 is a diagram to explain the accordion phenomenon. For example, in a traffic flow simulation (Reference: Yuta Imaeda, Akira Watanabe, Kensaku Asahi. Study on the effect of CACC on traffic congestion improvement by simulation. Proceedings of the 78th National Conference. 2016 Mar 10; 2016(1):373-4.), as shown in Figure 1, when the first vehicle decelerates from 90km / h to 75km / h, the speed of the second and subsequent vehicles decreases significantly, and the 10th vehicle repeats deceleration and acceleration. This phenomenon of repeated deceleration and acceleration is also seen in actual observation values ​​("Observation Value" in Figure 13).

[0034] Furthermore, the technology disclosed in Patent Document 2 is a technology for controlling vehicles relative to a set target speed, and is not a technology for determining how to set a target speed for efficient traffic flow.

[0035] This specification mainly describes a technology that enables more efficient control of the overall traffic flow on a road. More specifically, this specification describes a technology that enables reduction in unnecessary acceleration and deceleration, and reduces rear-end collisions at the end of a traffic jam.

[0036] The outline of the embodiment of the present invention has been described above.

[0037] 1. DETAILED DESCRIPTION OF THE EMBODIMENTS First, the details of the embodiments of the present invention will be described.

[0038] (1-1. Configuration of Traffic Flow Control Device) First, a configuration example of the traffic flow control device 1 according to an embodiment of the present invention will be described. FIG. 2 is a diagram showing a functional configuration example of the traffic flow control device 1 according to an embodiment of the present invention.

[0039] Referring to FIG. 2, as examples of vehicles traveling on the road, vehicles M1 to M3 are shown. Further, referring to FIG. 2, in the rear lane, vehicles M1 and M2 are traveling (vehicle M1 is traveling following vehicle M2), and in the front lane, vehicle M3 is traveling in the opposite direction to vehicles M1 and M2 in the rear lane. Thus, in the embodiment of the present invention, the case where the road is composed of multiple lanes is mainly assumed, but the road may be composed of a single lane. Each of vehicles M1 to M3 is equipped with an in-vehicle device 160.

[0040] The traffic flow control device 1 according to an embodiment of the present invention includes a travel history data storage unit 121, a probe data storage unit 122, a free flow data storage unit 123, a traffic volume data storage unit 124, a KV parameter storage unit 126, and a common parameter storage unit 127. Further, the traffic flow control device 1 according to an embodiment of the present invention includes a statistical processing unit 131, a traffic volume calculation unit 133, a traffic flow optimization unit 140, and a KV parameter creation unit 150.

[0041] The travel history data storage unit 121 is connected to a probe antenna 112, and the free flow data storage unit 123 is connected to a free flow antenna 114. Further, the traffic flow optimization unit 140 is connected to an information distribution antenna 116.

[0042] The statistical processing unit 131, the traffic volume calculation unit 133, the traffic flow optimization unit 140, and the KV parameter creation unit 150 include an arithmetic device such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), and their functions can be realized by a program stored in a ROM (Read Only Memory) being expanded and executed in a RAM by the arithmetic device. At this time, a computer-readable recording medium storing the program may also be provided.

[0043] Alternatively, the statistical processing unit 131, the traffic volume calculation unit 133, the traffic flow optimization unit 140, and the KV parameter creation unit 150 may be configured by dedicated hardware or may be configured by a combination of a plurality of hardware. Data necessary for arithmetic operations by the arithmetic device is appropriately stored by a storage unit (not shown).

[0044] The driving history data storage unit 121, the probe data storage unit 122, the free flow data storage unit 123, the traffic volume data storage unit 124, the KV parameter storage unit 126, and the common parameter storage unit 127 are stored by a storage unit (not shown). Such a storage unit may be configured by a memory such as a RAM (Random Access Memory), a hard disk drive, or a flash memory.

[0045] (Common parameter storage unit 127) The common parameter storage unit 127 stores various common parameters in advance. Here, examples of the common parameters will be described with reference to FIG. 3.

[0046] FIG. 3 is a diagram showing examples of various common parameters stored by the common parameter storage unit 127.

[0047] As shown in FIG. 3, the common parameter storage unit 127 stores the time width 71, the travel history point width 72, and the optimization execution time interval 73, respectively, as examples of common parameters. Further, the common parameter storage unit 127 stores the traffic jam determination speed 741 and the traffic jam determination distance 742, respectively, as examples of common parameters. Also, the common parameter storage unit 127 stores the speed control upstream maximum range 751, the speed control minimum speed 752, the speed control maximum speed 753, and the speed control width 754, respectively, as examples of common parameters.

[0048] (Free Flow Antenna 114) The free flow antenna 114 functions as an example of a vehicle detection unit that detects vehicles traveling at each position on the road. That is, in the embodiment of the present invention, the case where the vehicle detection unit includes the free flow antenna 114 is mainly assumed. Thereby, since the ETC free flow antenna of the already constructed ETC (Electronic Toll Collection) system can be used as the vehicle detection unit, it is not necessary to newly provide a vehicle detection unit. However, instead of the free flow antenna 114, other vehicle detection units (for example, vehicle sensors, infrared sensors, ultrasonic sensors, etc.) may be used.

[0049] More specifically, the free flow antenna 114 detects a vehicle in real time by receiving vehicle identification information (vehicle ID) from the vehicle through communication with an in-vehicle unit 160 mounted on the vehicle. In the embodiment of the present invention, the case where an ETC in-vehicle unit is used as an example of the in-vehicle unit 160 is mainly assumed. Note that while the free flow antenna 114 is assumed to be compatible with multiple versions of ETC in-vehicle units, the probe antenna 112 described later is assumed to be compatible with only a specific version of ETC in-vehicle unit. That is, the free flow antenna 114 can detect more vehicles than the probe antenna 112.

[0050] Note that the "each position" on the road where the vehicle is detected is not particularly limited as long as it is a position of the vehicle that can be detected by the vehicle detection unit. Hereinafter, each position on the road where the vehicle can be detected by the free flow antenna 114 may be simply referred to as the "free flow antenna position".

[0051] When the free flow antenna 114 detects a vehicle in real time by receiving a vehicle ID through communication with an in-vehicle device mounted on the vehicle, the detection result of the vehicle (hereinafter, also referred to as "free flow data") is output to the free flow data storage unit 123 in real time. Then, the detection result of the vehicle output from the free flow antenna 114 to the free flow data storage unit 123 in real time can be used in real time by the traffic volume calculation unit 133.

[0052] Here, "real time" may mean any timing within a short period from when the vehicle reaches the free flow antenna position until the traffic state on the road changes. If the vehicle is detected at this timing, some measures can be taken according to the traffic state at the time when the vehicle is detected before the traffic state on the road changes.

[0053] FIG. 4 is a diagram showing an example of free flow data stored by the free flow data storage unit 123. As shown in FIG. 4, the free flow data has a "vehicle ID" and a "passing time" associated with each other. The "vehicle ID" is identification information of the vehicle received from the vehicle through communication between the free flow antenna 114 and the in-vehicle device 160 mounted on the vehicle. The "passing time" is the time when the vehicle ID is received from the vehicle by the free flow antenna 114, and may correspond to the time when the vehicle passes the free flow antenna position.

[0054] (Traffic volume calculation unit 133) The traffic volume calculation unit 133 acquires the detection results (free flow data) of vehicles traveling at the free flow antenna position from the free flow data storage unit 123 (Fig. 4). Then, based on the free flow data (vehicle ID and passing time), the traffic volume calculation unit 133 calculates the number of vehicles passing through the free flow antenna position per unit time set in advance (the number of vehicle IDs detected per unit time by the free flow antenna 114) as the traffic volume at the free flow antenna position. The calculation of the traffic volume by the traffic volume calculation unit 133 may be repeated for each unit time.

[0055] Note that not all vehicles passing through the free flow antenna position are necessarily equipped with the in-vehicle device 160 capable of communicating with the free flow antenna 114. That is, not all vehicles passing through the free flow antenna position are detected by the free flow antenna 114. Therefore, when the ratio of the vehicles equipped with the in-vehicle device 160 capable of communicating with the free flow antenna 114 to the entire vehicle population (including vehicles not equipped with the in-vehicle device 160 capable of communicating with the free flow antenna 114) is set in advance as the "in-vehicle device installation ratio" and the number of vehicles detected by the free flow antenna 114 is defined as the "number of detected vehicles", it is desirable for the traffic volume calculation unit 133 to estimate the traffic volume at the free flow antenna position with higher accuracy using the following formula (1).

[0056] (Estimated traffic volume) = (Number of detected vehicles) ÷ (In-vehicle device installation ratio) ··· (1)

[0057] However, in cases where the in-vehicle device 160 capable of communicating with the free flow antenna 114 is sufficiently popular, such estimation may be omitted. The traffic volume estimated by the traffic volume calculation unit 133 and the unit time corresponding to the traffic volume are output to the traffic volume data storage unit 124 each time the traffic volume is estimated as traffic volume data.

[0058] (Probe antenna 112) The probe antenna 112 functions as an example of a driving history data acquisition unit that acquires driving history data of a vehicle. That is, in the embodiment of the present invention, it is mainly assumed that the driving history data acquisition unit includes the probe antenna 112. As a result, since the ETC probe antenna of the already constructed ETC system can be used as the driving history data acquisition unit, there is no need to newly provide a driving history data acquisition unit. However, instead of the probe antenna 112, other driving history data acquisition units (for example, mobile base stations, etc.) may be used.

[0059] More specifically, when the probe antenna 112 acquires driving history data from a vehicle through communication with an in-vehicle unit mounted on the vehicle, the acquired driving history data is output to the driving history data storage unit 121. Then, the driving history data output from the probe antenna 112 to the driving history data storage unit 121 can be utilized by the statistical processing unit 131.

[0060] Note that the driving history data includes the speed of each vehicle traveling in each section (between kilometer posts) on the road for each driving history point width 72 (for example, 100 m) and the collection time, which is the time when the speed was collected by the probe antenna 112.

[0061] (Statistical processing unit 131) The statistical processing unit 131 acquires driving history data from the driving history data storage unit 121, performs statistical processing on the driving history data, and outputs the driving history data after statistical processing as probe data to the probe data storage unit 122. Then, the probe data output from the statistical processing unit 131 to the probe data storage unit 122 can be utilized by the KV parameter creation unit 150.

[0062] For example, the statistical processing unit 131 performs predetermined statistical processing (for example, averaging processing, etc.) on the speeds of one or more vehicles that have traveled through each section (between kilometer posts) on the road for each driving history point width 72 at each time width 71. As a result, a statistical quantity of the vehicle speed per unit time in each section on the road is obtained. Note that examples of the averaging processing include processing for taking the harmonic mean.

[0063] FIG. 5 is a diagram showing an example of probe data stored by the probe data storage unit 122. As shown in FIG. 5, the probe data has "passing time", "kilometer post", "vehicle speed", and "collection time" associated with each other.

[0064] The "passing time" is the time when the vehicle passes the distance marker (kilometer post) from the starting point of the road. The "kilometer post" is the distance marker from the starting point of the road.

[0065] The "speed" is a statistical quantity (for example, average speed) of the speeds of one or more vehicles that have traveled through each section (between kilometer posts) on the road at each time width 71 (between passing times). For example, "speed: 80 km / h" is a statistical quantity of the speeds of one or more vehicles that have traveled from "kilometer post: 100" to "kilometer post: 100.1" from "passing time: 10:23 on January 1, 2019" to "10:24 on January 1, 2019".

[0066] The "collection time" is the time when the vehicle speed is collected by the probe antenna 112.

[0067] (KV parameter creation unit 150) The KV parameter creation unit 150 acquires the speed and unit time for a predetermined period for each free flow antenna position from the probe data storage unit 122. Further, the KV parameter creation unit 150 acquires traffic volume data (traffic volume and unit time) for a predetermined period for each free flow antenna position from the traffic volume data storage unit 124.

[0068] The KV parameter creation unit 150 creates, for each free-flow antenna position, parameters indicating the correspondence relationship (in the following example, an approximate formula) between traffic density (K) and speed (V) by machine learning based on the traffic volume and unit time for a predetermined period and the speed and unit time for the same predetermined period.

[0069] More specifically, the KV parameter creation unit 150 associates the traffic volume (Q) and speed (V) corresponding to the same unit time and the same free-flow antenna position. Then, the KV parameter creation unit 150 calculates the traffic density (K) for each associated traffic volume (Q) and speed (V) according to the following formula (2).

[0070] K = Q × 1 / (V × 60) ··· (2)

[0071] However, K represents the traffic density (vehicles / km), Q represents the traffic volume (vehicles / minute), and V represents the speed (km / hour). The KV parameter creation unit 150 approximates the set of corresponding traffic density (K) and speed (V) in a predetermined relationship, and creates the parameters of the approximate formula (KV relational formula) obtained by the approximation as KV parameters.

[0072] Here, it is assumed that the KV parameter creation unit 150 creates the parameters of the approximate formula corresponding to the congested flow. More specifically, it is assumed that the KV parameter creation unit 150 creates the parameters of the KV relational formula corresponding to the congested flow by approximating the set of speeds (V) below the congestion determination speed 741 (for example, 40 km / h on a highway etc.) and the traffic density (K) corresponding to that speed (V) in a predetermined relationship. For example, the KV relational formula may be an exponential function expressed by the following formula (3).

[0073] V = a × exp(-b × K) ··· (3)

[0074] However, K represents the traffic density (vehicles / km), V represents the speed (km / hour), and a and b are KV parameters.

[0075] FIG. 6 is a diagram showing a set of traffic density (K) and speed (V) and a KV relational expression. In the example shown in FIG. 6, the horizontal axis represents the traffic density (K), and the vertical axis represents the speed (V). In such a KV diagram, each set in which the traffic density (K) and the speed (V) are associated is plotted as each point. Further, referring to FIG. 6, an exponential function showing the KV relational expression obtained by approximating these sets is shown.

[0076] The KV parameter creation unit 150 stores the created KV parameters in the KV parameter storage unit 126. Typically, the predetermined period may be one month. However, the predetermined period is not limited to one month. For example, the predetermined period may be one day.

[0077] FIG. 7 is a flowchart showing an example of the KV parameter creation process executed by the KV parameter creation unit 150. First, the KV parameter creation unit 150 acquires the speed and unit time for a predetermined period for each free flow antenna position from the probe data storage unit 122 (S11). Further, the KV parameter creation unit 150 acquires the traffic volume data (traffic volume and unit time) for a predetermined period for each free flow antenna position from the traffic volume data storage unit 124 (S12).

[0078] The KV parameter creation unit 150 associates the traffic volume (Q) and the speed (V) corresponding to the same unit time and the same free flow antenna position. Then, the KV parameter creation unit 150 calculates the traffic density (K) for each of the associated traffic volume (Q) and speed (V) (S13).

[0079] The KV parameter creation unit 150 creates parameters of a KV relational expression indicating the relationship between traffic density (K) and speed (V) by machine learning (S14). More specifically, the KV parameter creation unit 150 approximates a set of corresponding traffic density (K) and speed (V) with a predetermined relationship (for example, an exponential function, etc.), and creates the parameters of the KV relational expression obtained by the approximation as KV parameters. Here, it is assumed that the KV parameter creation unit 150 creates parameters of an approximation formula corresponding to congested flow.

[0080] The KV parameter creation unit 150 stores the created KV parameters in the KV parameter storage unit 126 (S15).

[0081] (Traffic density calculation unit 141) The traffic density calculation unit 141 acquires, from the probe data storage unit 122, the speed and unit time for each section from the current time to a predetermined set time before (for example, one hour before, etc.) at a preset optimization execution time interval 73 (for example, a 5-minute interval, etc.). Also, the traffic density calculation unit 141 acquires, from the traffic volume data storage unit 124, the traffic volume data (traffic volume and unit time) for each free flow antenna position from the current time to a predetermined set time before at the optimization execution time interval 73.

[0082] The traffic density calculation unit 141 calculates the traffic density for each section based on at least the speed in each section. Here, the calculation of the traffic density for each section may be specifically calculated in any manner.

[0083] For example, the traffic density calculation unit 141 may acquire KV parameters from the KV parameter storage unit 126, and calculate the traffic density in a target section (the first section) on the road based on the speed in the target section and the KV relational expression defined by the KV parameters.

[0084] More specifically, the traffic density calculation unit 141 may calculate the traffic density in a section where traffic is congested, that is, a target section where the speed is equal to or lower than the congestion determination speed 741 (threshold value), based on the speed in the target section and the KV relational expression.

[0085] Further, the traffic density calculation unit 141 may use the free flow antenna position based on a certain target section (second section) on the road as the measurement position, the point corresponding to the target section as the estimated point, and calculate the traffic density in the target section based on the traffic volume at the estimated point and the speed in the target section. For example, the measurement position may be the free flow antenna position upstream from the target section (for example, the free flow antenna position closest to the target section upstream). Also, the estimated point may be the starting point of the target section or the like.

[0086] More specifically, the traffic density calculation unit 141 may calculate the traffic density in a target section where the speed exceeds the congestion determination speed 741 (threshold value), based on the traffic volume at the estimated point and the speed in the target section. For example, the traffic density calculation unit 141 may calculate the traffic volume at the estimated point based on the traffic volume at the measurement point calculated by the traffic volume calculation unit 133 and the speed for each section from the measurement point to the target section.

[0087] An example of a method for calculating the traffic density in a target section based on the traffic volume at the estimated point and the speed in the target section will be described with reference to FIGS. 8 and 9.

[0088] FIG. 8 is a diagram for explaining an example of calculating the passing time at the measurement point of a vehicle that has reached the estimated point. In the example shown in FIG. 8, the horizontal axis represents the distance on the road (the right direction is the downstream direction of the road), and the vertical axis represents the time (the downward direction is the direction of time elapse). The speed corresponding to the section (between kilometer posts) and the unit time (between passing times) in the travel history data is indicated by the darkness of the color within the rectangle (space-time range) corresponding to the section and the unit time. In this example, the darker the color within the rectangle, the lower the speed.

[0089] Based on the speeds corresponding to each section and time, the traffic density calculation unit 141 calculates the trajectories from the estimated point and the time at the estimated point to the measurement points upstream and towards the past. More specifically, the traffic density calculation unit 141 moves within the rectangle along a straight line with a slope corresponding to the speed corresponding to each section and time from the estimated point and the time at the estimated point, and calculates the trajectory so as to move between adjacent rectangles at the boundaries of the rectangle.

[0090] Thereby, the traffic density calculation unit 141 can obtain the time at the measurement point reached by the trajectory as the passing time at the measurement point. Referring to FIG. 8, the trajectories of two vehicles are drawn. Here, it can be considered that the traffic volume between the arrival times of the two vehicles at the estimated point is the same as the traffic volume between the passing times of the two vehicles at the measurement point.

[0091] FIG. 9 is a diagram for explaining an example of calculating the traffic volume at the estimated point from the traffic volume at the measurement point. Referring to FIG. 9, the traffic volume Q between the arrival times at the estimated point and the traffic volume Q between the passing times at the measurement point are shown. Here, the traffic volume between the passing times at the measurement point is stored in the traffic volume data storage unit 124. Therefore, the traffic density calculation unit 141 can acquire the traffic volume Q between the passing times at the measurement point from the traffic volume data storage unit 124.

[0092] The traffic density calculation unit 141 can calculate the traffic volume at the estimated point from the traffic volume Q between the passing times at the measurement point by the ratio of the difference in arrival times at the estimated point to the difference in passing times at the measurement point. For example, if the difference in passing times at the measurement point is t1 and the difference in arrival times at the estimated point is t2, the traffic density calculation unit 141 can calculate the traffic volume at the estimated point by multiplying the traffic volume Q between the passing times at the measurement point by t1 / t2.

[0093] FIG. 10 is a flowchart showing an example of traffic density calculation processing executed by the traffic density calculation unit 141. First, the traffic density calculation unit 141 acquires, from the probe data storage unit 122, the speed and unit time for each section from the current time to a predetermined set time before, at a preset optimization execution time interval 73 (S21).

[0094] Also, the traffic density calculation unit 141 acquires, from the traffic volume data storage unit 124, the traffic volume data (traffic volume and unit time) for each free flow antenna position from the current time to a predetermined set time before, at the optimization execution time interval 73 (S22). The traffic density calculation unit 141 determines whether the speed of the target section is the speed of a congested flow, that is, a speed equal to or lower than the congestion determination speed 741 (threshold value) (S23).

[0095] If the speed of the target section is the speed of a congested flow (\"YES\" in S23), the traffic density calculation unit 141 calculates the traffic density in the target section based on the speed in the target section and the KV relational expression (S24). On the other hand, if the speed of the target section is the speed of a free flow (\"NO\" in S23), the traffic density calculation unit 141 calculates the traffic volume at the measurement point by vehicle tracking, and calculates the traffic density in the target section based on the calculated traffic volume at the measurement point and the speed for each section from the measurement point to the target section (S25).

[0096] (Traffic flow simulation unit 142) The traffic flow simulation unit 142 functions as an example of a determination unit.

[0097] (Generation of speed control pattern) The traffic flow simulation unit 142 generates a plurality of speed control patterns. Here, each of the plurality of speed control patterns is constituted by a combination of a control range and a control speed on a road where the vehicle speed is controlled to a predetermined control speed in the simulation. For example, the traffic flow simulation unit 142 determines the control range based on the position of a congestion flow point where the speed is equal to or lower than the congestion determination speed 741, or a congestion flow point where the traffic density is equal to or higher than the congestion determination traffic density (for example, 20 vehicles / km·lane on a highway). Thereby, it can be expected that the congestion flow is reduced or the occurrence of congestion is suppressed. Note that the congestion determination traffic density may correspond to an example of a threshold value.

[0098] With reference to FIG. 11, an example of generating a speed control pattern will be described. FIG. 11 is a diagram for explaining an example of generating a speed control pattern. Referring to FIG. 11, the measurement start point and the measurement end point of the speed are shown. The traffic density based on the speed (observed value) in each section from the measurement start point to the measurement end point at time t has been calculated. At this time, consider generating a speed control pattern at time t + 1.

[0099] FIG. 11 shows a "congestion flow point". The traffic flow simulation unit 142 detects the position of a section where the speed is equal to or lower than the congestion determination speed 741 at time t as the position of the congestion flow point. Note that the traffic flow simulation unit 142 may detect the position of a section where the traffic density is equal to or higher than the congestion determination traffic density at time t as the position of the congestion flow point. Hereinafter, the case where the congestion flow point is detected by the traffic flow simulation unit 142 will be described. However, in the following description, the congestion flow point may be replaced with a congestion flow point.

[0100] At this time, the traffic flow simulation unit 142 may always execute the simulation when the position of the traffic jam point is detected, or may execute the simulation when the length of the traffic jam point is equal to or greater than the traffic jam determination distance 742 (predetermined length). When the road to be measured is a general road, the traffic jam determination distance 742 may be 100 m or the like. Alternatively, when the road to be measured is an expressway, the traffic jam determination distance 742 may be 500 m or the like.

[0101] The traffic flow simulation unit 142 determines the control range based on the position of the traffic jam point at this time t. More specifically, the traffic flow simulation unit 142 calculates each position obtained by moving the starting point of the position of the traffic jam point upstream by the speed control width 754 (for example, 1 km) at a time up to the speed control upstream maximum range 751 (for example, 5 km) as the starting points P1 to P5 of the control range. Further, the traffic flow simulation unit 142 calculates each position obtained by moving the starting points P1 to P5 of the control range downstream by the speed control width 754 (for example, 1 km) as the end points R1 to R5 of the control range.

[0102] In addition, the traffic flow simulation unit 142 calculates each speed increased from the speed control minimum speed 752 by the speed control width 754 up to the speed control maximum speed 753 as the control speeds V1 to V6 (20 km / h to 70 km / h).

[0103] The traffic flow simulation unit 142 uses the combination of (starting point, end point, speed) calculated in this way as a speed control pattern and generates a plurality of speed control patterns. In the example shown in FIG. 11, 15 combinations (number of combinations of starting point and end point) × 6 patterns (number of speed patterns) = 90 speed control patterns are generated. However, the example of generating the speed control pattern shown in FIG. 11 is only an example. Therefore, the generation of the speed control pattern is not limited to the example shown in FIG. 11.

[0104] (Execution of Simulation) The traffic flow simulation unit 142 executes a simulation of the change in traffic density in each section for each speed control pattern based on the plurality of speed control patterns generated in this way and the traffic density in each section calculated by the traffic density calculation unit 141. The execution of the simulation will be described with reference to FIGS. 12 and 13.

[0105] FIG. 12 is a diagram showing an example of the traffic density used in the execution of the simulation. As described above, a simulation is executed for each of the plurality of speed control patterns (in the example shown in FIG. 11, 90 speed control patterns). In the example shown in FIG. 12, it is assumed that a simulation is executed for one speed control pattern (starting point, ending point, speed) = (P5, R5, V4) among the 90 speed control patterns.

[0106] Referring to FIG. 12, the traffic density K m (t) in each section m (1 ≦ m ≦ n) at time t calculated by the traffic density calculation unit 141 is shown. These are the observed values of the traffic density. Further, based on the KV relational expression, the traffic flow simulation unit 142 converts the speed V4 (= 50 km / h) included in the speed control pattern into the traffic density K V4 (t + 1). As shown in FIG. 12, the traffic density K V4 (t + 1) is used as the traffic density K V4 (t + 1) at time t + 1 from the starting point P5 to the ending point R5 included in the speed control pattern.

[0107] As an example, the traffic flow simulation unit 142 causes the simulation to be executed with the traffic density K m (t) in each section m (1 ≦ m ≦ n) at time t and the traffic density K V4 (t + 1) at time t + 1 as inputs to the simulation. Then, based on these inputs, the traffic density in the sections other than the section from the starting point P5 to the ending point R5 at time t + 1 and the traffic density in each section at time t + 2 are output as the execution results of the simulation.

[0108] Note that, as simulations, for example, ADVENTURE_Mates developed by the University of Tokyo (Reference: Yoshiyuki Iida, Hideki Fujii, and Shinobu Yoshimura. "Development and Evaluation of a Remote Execution Environment for Traffic Flow Simulation." Proceedings of the Computational Mechanics Symposium 2016.29. The Japan Society of Mechanical Engineers, 2016.) or SUMO (Simulation of Urban Mobility; URL: https: / / kudzuyu.github.io / SUMO-wiki-ja / ) mainly developed by the Institute of Transportation Systems at the German Aerospace Center can be used.

[0109] (Determination of Control Pattern) The traffic flow simulation unit 142 determines, as the determination pattern (optimal speed control pattern), the speed control pattern with the smallest statistical quantity (for example, median, average value, or trimmed average value, etc.) of at least vehicle acceleration based on the execution result of the simulation. For example, the speed control pattern with the smallest statistical quantity of vehicle acceleration can contribute to the reduction of carbon dioxide emissions from vehicles.

[0110] More specifically, for each of the plurality of speed control patterns, the traffic flow simulation unit 142 converts the traffic density in each section at time t + 2 into speed based on the KV relational expression. Then, the traffic flow simulation unit 142 determines, as the determination pattern, the speed control pattern with the smallest statistical quantity of at least vehicle acceleration based on the speed in each section from the measurement start point to the measurement end point at time t + 2.

[0111] The traffic flow simulation unit 142 may determine the determination pattern taking into account vehicle deceleration in addition to vehicle acceleration. That is, the traffic flow simulation unit 142 may determine, as the determination pattern, the speed control pattern with the smallest statistical quantity of vehicle acceleration and vehicle deceleration (for example, median, average value, or trimmed average value, etc.) based on the execution result of the simulation. For example, the speed control pattern with the smallest statistical quantity of vehicle deceleration can contribute to the reduction of the driving burden on the driver of the vehicle.

[0112] More specifically, for each of a plurality of speed control patterns, the traffic flow simulation unit 142 converts the traffic density in each section at time t + 2 into speed based on the KV relational expression. Then, the traffic flow simulation unit 142 may determine, as a determination pattern, the speed control pattern with the smallest statistical amounts of vehicle acceleration and vehicle deceleration based on the speeds in each section from the measurement start point to the measurement end point at time t + 2.

[0113] FIG. 13 is a diagram for explaining an example of an optimal speed control pattern. The horizontal axis of the graph in FIG. 13 indicates the position of each measurement range from the measurement start point to the measurement end point, and the vertical axis of the graph indicates the vehicle speed.

[0114] Here, the "observed value" is the speed for each actually measured section, and there is a traffic jam point where the speed has dropped to 40 km / h or less. On the other hand, the "simulation optimal value" indicates the vehicle speed based on the execution result of the simulation when a speed control pattern for controlling the speed to 50 km / h from 5 km upstream to 4 km upstream of the traffic jam point is determined, and a state where the vehicle speed is higher than 40 km / h is maintained.

[0115] (Information distribution antenna 116) The information distribution antenna 116 communicates with an in-vehicle device 160 mounted on the vehicle. As an example, the information distribution antenna 116 transmits speed control information corresponding to the determination pattern to the in-vehicle device 160 according to the control by the transmission control unit 143. Note that the information distribution antenna 116 may be integrated with the probe antenna 112 or may exist separately from the probe antenna 112. For example, the information distribution antenna 116 may be a mobile base station.

[0116] (Transmission control unit 143) The transmission control unit 143 controls the transmission by the information distribution antenna 116 of speed control information according to the determined pattern determined from a plurality of speed control patterns by the traffic flow simulation unit 142. For example, the transmission control unit 143 controls the transmission by the information distribution antenna 116 of speed control information to the in-vehicle device 160 (first in-vehicle device) mounted on the vehicle.

[0117] Note that the transmission control unit 143 may include the speed included in the determined pattern in the speed control information. Further, the transmission control unit 143 may include the start point and the end point included in the determined pattern in the speed control information. However, when the transmission control unit 143 outputs transmission control information to the information distribution antenna 116 at a position corresponding to the start point or the end point included in the determined pattern (for example, the information distribution antenna 116 closest to the start point or the end point), the speed control information does not have to include the start point and the end point included in the determined pattern.

[0118] (In-vehicle device 160) The in-vehicle device 160 includes a receiving unit that receives the speed control information transmitted by the information distribution antenna 116. Further, the in-vehicle device 160 includes a speed control unit that controls an ACC (Adaptive Cruise Control) module or an automatic driving module so that the vehicle travels at a speed corresponding to the speed control information received by the receiving unit.

[0119] For example, the speed control unit controls the ACC module or the automatic driving module so that the vehicle travels at the speed included in the speed control information. At this time, the ACC module or the automatic driving module controls the speed of the vehicle according to the control by the speed control unit. However, the ACC module or the automatic driving module gives priority to the control of the vehicle speed for accident avoidance based on the information acquired by an in-vehicle camera or a sensor or the like.

[0120] For example, when the starting point is included in the speed control information, if it is detected that the current position of the vehicle has reached a point a predetermined distance ahead of the starting point included in the speed control information, the ACC module or the automatic driving module may be controlled so that the vehicle travels at the speed included in the speed control information.

[0121] The configuration example of the traffic flow control device 1 according to the embodiment of the present invention has been described above.

[0122] (1-2. Effects) As described above, the traffic flow control device 1 according to the embodiment of the present invention executes a simulation of the change in traffic density in each section for each speed control pattern based on the traffic density in each section on the road and a plurality of speed control patterns, and determines, as a determination pattern, the speed control pattern in which at least the statistical amount of vehicle acceleration based on the execution result of the simulation is the smallest. The traffic flow control device 1 also includes a transmission control unit that controls the transmission of speed control information according to the determination pattern.

[0123] According to such a configuration, it becomes possible to control the traffic flow on the road more efficiently. Furthermore, according to such a configuration, since the acceleration of the vehicle is reduced, the amount of carbon dioxide emissions from the vehicle can also be reduced. Also, if a speed control pattern that decelerates more gently is determined, the effect of preventing rear-end collisions at the end of traffic jams can also be achieved.

[0124] The effects exhibited by the traffic flow control device 1 according to the embodiment of the present invention have been described above.

[0125] (2. Various Modification Examples) Subsequently, various modification examples will be described. As described above, the in-vehicle device 160 includes a receiving unit that receives the speed control information transmitted by the information distribution antenna 116. Furthermore, the in-vehicle device 160 may include a driver presentation unit that presents presentation information based on the reception of the speed control information transmitted by the information distribution antenna 116 to the driver of the vehicle.

[0126] As a result, even in the in-vehicle device 160 that is not connected to the ACC module or the automatic driving module, it is possible to notify the driver of the presentation information based on the received speed control information. Therefore, when the driver drives the vehicle according to the presentation information, similar to the above-described embodiment, the amount of carbon dioxide emissions from the vehicle can be reduced, and the effect of preventing a rear-end collision at the end of traffic congestion can be achieved.

[0127] For example, the driver presentation unit may be configured by a presentation device such as a display or a speaker.

[0128] FIG. 14 is a diagram showing an example of presenting presentation information. As shown in FIG. 14, the presentation information may include display information G10 displayed by the display 161 and voice information D10 output by the speaker. When the speed control information includes a speed control instruction, as shown in FIG. 14, the presentation information may be information such as "Traffic jam ahead, beware of rear-end collision" indicating simply limiting the speed.

[0129] Alternatively, when the speed control information includes a speed, the presentation information may include information indicating that speed. For example, the voice information D10 may include information indicating the speed such as "Please reduce the speed to 50 km / h". Alternatively, the display information G10 may include a blinking display of information indicating the speed such as "50".

[0130] Alternatively, when the speed control information includes a starting point, the presentation information may include information indicating that starting point such as "There is a traffic jam 1 km ahead". Alternatively, when the speed control information includes a starting point, the driving presentation unit may present the presentation information at the timing when it is detected that the current position of the vehicle has reached a point a predetermined distance before the starting point included in the speed control information.

[0131] As another modification, the transmission control unit 143 may control the transmission of the speed control information to the electronic display board installed on the road.

[0132] Accordingly, even for a driver of a vehicle equipped with the in-vehicle device 160 that is not connected to the ACC module or the automatic driving module, it is possible to notify the presentation information based on the received speed control information. Therefore, when the driver drives the vehicle according to the presentation information, similar to the above-described embodiment, the amount of carbon dioxide emissions from the vehicle can be reduced, and the effect of preventing a rear-end collision at the end of traffic congestion can be achieved.

[0133] Also, as another modification, the in-vehicle device 160 may include a following vehicle presentation unit that presents presentation information based on the received speed control information transmitted by the information distribution antenna 116 to the driver of the following vehicle. The location where the presentation information is presented by the following vehicle presentation unit may be a display screen of the rear window or the like.

[0134] Accordingly, even for a driver of a following vehicle equipped with the in-vehicle device 160 that is not connected to the ACC module or the automatic driving module, it is possible to notify the presentation information based on the received speed control information. Therefore, when the driver of the following vehicle drives the vehicle according to the presentation information, similar to the above-described embodiment, the amount of carbon dioxide emissions from the following vehicle can be reduced, and the effect of preventing a rear-end collision at the end of traffic congestion can be achieved.

[0135] Furthermore, as another modification, the transmission control unit 143 may control the transmission of the speed control information to the first in-vehicle device by the first transmission unit (for example, the information distribution antenna 116, etc.) of the speed control information, and output the speed control information to a second transmission unit different from the first transmission unit (for example, an information distribution antenna different from the information distribution antenna 116). At this time, the second transmission unit may convert the protocol of the speed control information according to a second communication protocol different from the first communication protocol used by the first in-vehicle device, and transmit the speed control information after the protocol conversion to the second in-vehicle device using the second communication protocol.

[0136] This makes it possible to transmit speed control information even to a second vehicle-mounted device that uses a second communication protocol different from the first communication protocol used by the first vehicle-mounted device. Therefore, presentation information based on the speed control information can be presented to the driver of the vehicle equipped with the second vehicle-mounted device or to a following vehicle of the said vehicle.

[0137] (3. Hardware Configuration Example) Next, a hardware configuration example of the traffic flow control device 1 according to an embodiment of the present invention will be described.

[0138] Hereinafter, as a hardware configuration example of the traffic flow control device 1 according to an embodiment of the present invention, a hardware configuration example of an information processing device 900 will be described. Note that the hardware configuration example of the information processing device 900 described below is merely an example of the hardware configuration of the traffic flow control device 1. Therefore, the hardware configuration of the traffic flow control device 1 may have unnecessary configurations deleted from the hardware configuration of the information processing device 900 described below, or new configurations may be added.

[0139] FIG. 15 is a diagram showing a hardware configuration of an information processing device 900 as an example of the traffic flow control device 1 according to an embodiment of the present invention. The information processing device 900 includes a CPU (Central Processing Unit) 901, a ROM (Read Only Memory) 902, a RAM (Random Access Memory) 903, a host bus 904, a bridge 905, an external bus 906, an interface 907, an input device 908, an output device 909, a storage device 910, and a communication device 911.

[0140] The CPU 901 functions as an arithmetic processing unit and a control unit, and controls the overall operations within the information processing apparatus 900 according to various programs. Also, the CPU 901 may be a microprocessor. The ROM 902 stores programs, arithmetic parameters, etc. used by the CPU 901. The RAM 903 temporarily stores programs used in the execution of the CPU 901 and parameters that change as appropriate during the execution. These are interconnected by a host bus 904 composed of a CPU bus or the like.

[0141] The host bus 904 is connected to an external bus 906 such as a PCI (Peripheral Component Interconnect / Interface) bus via a bridge 905. Note that it is not necessarily required to separately configure the host bus 904, the bridge 905, and the external bus 906, and these functions may be implemented on a single bus.

[0142] The input device 908 is composed of input means such as a mouse, keyboard, touch panel, button, microphone, switch, and lever for the user to input information, and an input control circuit that generates an input signal based on the user's input and outputs it to the CPU 901. The user who operates the information processing apparatus 900 can input various data to the information processing apparatus 900 or instruct processing operations by operating this input device 908.

[0143] The output device 909 includes, for example, a display device such as a CRT (Cathode Ray Tube) display device, a liquid crystal display (LCD) device, an OLED (Organic Light Emitting Diode) device, a lamp, and an audio output device such as a speaker.

[0144] The storage device 910 is a device for storing data. The storage device 910 may include a storage medium, a recording device for recording data on the storage medium, a reading device for reading data from the storage medium, a deleting device for deleting data recorded on the storage medium, and the like. The storage device 910 is configured by, for example, an HDD (Hard Disk Drive). This storage device 910 drives a hard disk and stores programs executed by the CPU 901 and various data.

[0145] The communication device 911 is a communication interface configured by, for example, a communication device for connecting to a network. Further, the communication device 911 may support either wireless communication or wired communication.

[0146] The hardware configuration example of the traffic flow control device 1 according to the embodiment of the present invention has been described above.

[0147] (4. Summary) The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that those having ordinary knowledge in the technical field to which the present invention pertains can conceive of various modification examples or correction examples within the scope of the technical idea described in the claims, and it is naturally understood that these also belong to the technical scope of the present invention.

[0148] In the above, the term "location" is used, but this term "location" can represent not only a single point but also a place having a certain range. Therefore, this term "location" can also be paraphrased as the term "section".

Explanation of Reference Numerals

[0149] 1 Traffic flow control device 112 Probe antenna 114 Free flow antenna 116 Information distribution antenna 121 Travel history data storage unit 122 Probe Data Storage Unit 123 Free Flow Data Storage Unit 124 Traffic Volume Data Storage Unit 126 KV Parameter Storage Unit 127 Common Parameter Storage Unit 131 Statistical Processing Unit 133 Traffic Volume Calculation Unit 140 Traffic Flow Optimization Unit 141 Traffic Density Calculation Unit 142 Traffic Flow Simulation Unit 143 Transmission Control Unit 150 KV Parameter Creation Unit 160 On-vehicle Device 161 Display

Claims

1. A traffic density calculation unit that calculates the traffic density in each section based on at least the statistical quantity of the vehicle speed in each section on the road; Based on the traffic density in each section and a plurality of speed control patterns, by simulating the change in traffic density in each section for each of the plurality of speed control patterns, for each of the plurality of speed control patterns, the traffic density at a later time in each section is obtained as the result of the simulation execution, and a determination unit that determines the speed control pattern with the smallest statistical quantity of at least vehicle acceleration based on the result of the simulation execution as the determination pattern; A transmission control unit that controls the transmission of speed control information according to the determination pattern; A traffic flow control device comprising:

2. Each of the plurality of speed control patterns is constituted by a combination of a control range on the road where the vehicle speed is controlled to a predetermined control speed in the simulation and the control speed; The traffic flow control device according to Claim 1.

3. The determination unit determines the control range based on the position of a traffic jam section where the statistical quantity of the vehicle speed is equal to or less than a threshold value, or a congested flow section where the traffic density is equal to or greater than a threshold value; The traffic flow control device according to Claim 2.

4. The determination unit executes the simulation when the length of the traffic jam section or the congested flow section is equal to or greater than a predetermined length; The traffic flow control device according to Claim 3.

5. The traffic density calculation unit calculates the traffic density in the first section based on the statistical quantity of the vehicle speed in the first section on the road and a relational expression indicating the relationship between traffic density and vehicle speed; The traffic flow control device according to any one of Claims 1 to 4.

6. The first section is a section where the statistical quantity of the vehicle speed is equal to or less than a threshold value; The traffic flow control device according to Claim 5.

7. The traffic flow control device includes a parameter creation unit that creates parameters of the relational expression by machine learning; The traffic flow control device according to Claim 5 or 6.

8. The traffic flow control device includes a traffic volume calculation unit that calculates the traffic volume at a predetermined measurement point on the road based on the detection result of a vehicle traveling at the predetermined measurement point on the road. The traffic density calculation unit calculates the traffic volume in the second section based on the traffic volume at the predetermined measurement point and the statistical quantity of the vehicle speed for each section from the predetermined measurement point to the second section on the road, and calculates the traffic density in the second section based on the traffic volume in the second section and the statistical quantity of the vehicle speed in the second section. The traffic flow control device according to any one of claims 1 to 7.

9. The second section is a section where the statistical quantity of the vehicle speed exceeds a threshold value. The traffic flow control device according to claim 8.

10. The determination unit determines, as the determination pattern, the speed control pattern in which the statistical quantities of the vehicle acceleration and the vehicle deceleration based on the execution result of the simulation are the smallest. The traffic flow control device according to any one of claims 1 to 9.

11. The transmission control unit controls the transmission of the speed control information to the first in-vehicle device. The traffic flow control device according to any one of claims 1 to 10.

12. The first in-vehicle device includes a receiving unit that receives the speed control information, and a speed control unit that controls an ACC module or an automatic driving module so that the vehicle travels at a speed corresponding to the speed control information received by the receiving unit. The traffic flow control device according to claim 11.

13. The first in-vehicle device includes a receiving unit that receives the speed control information, and a driver presentation unit that presents presentation information based on the reception of the speed control information by the receiving unit to the driver of the vehicle. The traffic flow control device according to claim 11.

14. The first in-vehicle device includes a receiving unit that receives the speed control information, and a following vehicle presentation unit that presents presentation information based on the reception of the speed control information by the receiving unit to the driver of the following vehicle. The traffic flow control device according to claim 11.

15. The transmission control unit controls the transmission of the speed control information to the first in-vehicle device by the first transmission unit, and outputs the speed control information to a second transmission unit different from the first transmission unit. The second transmission unit converts the protocol of the speed control information according to a second communication protocol different from the first communication protocol used by the first in-vehicle device, and transmits the speed control information after the protocol conversion to a second in-vehicle device that uses the second communication protocol. The traffic flow control device according to claim 11.

16. The transmission control unit controls the transmission of the speed control information to the electronic display board installed on the road. The traffic flow control device according to any one of claims 1 to 10.

17. Calculating the traffic density in each section based on at least the statistical quantity of the vehicle speeds in each section on the road; Based on the traffic density in each section and a plurality of speed control patterns, by performing a simulation of the change in traffic density in each section for each of the plurality of speed control patterns, for each of the plurality of speed control patterns, obtaining the traffic density at a later time in each section as the result of the simulation execution, and determining, as a determination pattern, the speed control pattern in which at least the statistical quantity of vehicle acceleration based on the simulation execution result is the smallest; Controlling the transmission of speed control information according to the determination pattern; A traffic flow control method including the above.

18. A computer, A traffic density calculation unit that calculates the traffic density in each section based on at least the statistical quantity of the vehicle speeds in each section on the road; Based on the traffic density in each section and a plurality of speed control patterns, by performing a simulation of the change in traffic density in each section for each of the plurality of speed control patterns, for each of the plurality of speed control patterns, obtaining the traffic density at a later time in each section as the result of the simulation execution, and a determination unit that determines, as a determination pattern, the speed control pattern in which at least the statistical quantity of vehicle acceleration based on the simulation execution result is the smallest; A transmission control unit that controls the transmission of speed control information according to the determination pattern; A program for causing the computer to function as a traffic flow control device including the above.

Images