Traffic flow control system

Abstract

The purpose of the present invention is to efficiently allow vehicles to pass through an intersection by controlling the traffic flow at the intersection at the lane level. This traffic flow control system (1) has a server device (10) which controls the traffic flow of vehicles passing through an intersection at which roads having one or a plurality of lanes intersect. The server device (10) comprises: a zone division unit (101) that divides the intersection into a plurality of zones in accordance with the shape of the intersection and the arrangement of the entrance / exit of the intersection; a pass number calculation unit (102) that calculates, for each lane in each zone, the number of vehicles that can pass through the lanes in the respective zones at the same time; a key package management unit (104) that allocates, to each lane in each zone, a key that gives permission for vehicles (20) to enter the lanes in the respective zones, by the calculated number of vehicles; and a key distribution unit (109) that distributes the keys to the vehicles (20) in accordance with the travel route at the intersection planned by the vehicles (20). The vehicles (20) travel according to a travel route upon receiving the key distributed from the server device (10).

Description

[Technical Field]

[0001] The present invention relates to a traffic flow control system. [Background technology]

[0002] 2. Description of the Related Art Systems for controlling the flow of vehicles passing through intersections are known.

[0003] Patent Document 1 discloses a traffic flow control system for controlling the traffic flow of mobile objects traveling on a traffic route. The system disclosed in Patent Document 1 includes an area management device provided for each area obtained by virtually dividing the traffic route, and an exit route management device provided for each exit route of the traffic route. The exit route management device has an occupancy right management unit that manages the occupancy right of the exit route it is responsible for, and a communication unit that communicates with the mobile object or the area management device. The area management device has a destination acquisition unit that acquires the exit route that is the destination of the mobile object, an entry right management unit that manages the entry right of the area it is responsible for, and a communication unit that communicates with the mobile object, the exit route management device, or another area management device. When the mobile object requests entry right into the area it is responsible for, the entry right management unit of the area management device transmits the token with the entry right attached to it to the mobile object if the occupancy right management unit of the exit route management device that is responsible for the exit route that is the destination of the mobile object holds the occupancy right and holds the entry right and a token. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-14625 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the system disclosed in Patent Document 1, each area management device in principle holds only one token that is sent to a mobile object along with the right to enter the area. Therefore, in the system disclosed in Patent Document 1, it is difficult to control traffic flow at an intersection at the lane level, and there is room for improvement in terms of efficiently passing vehicles through intersections.

[0006] The present invention has been made in view of the above, and has as its object to control traffic flow at an intersection at the lane level to allow vehicles to pass through the intersection efficiently. [Means for solving the problem]

[0007] In order to solve the above problem, the traffic flow control system of the present invention is a traffic flow control system having a server device that controls the traffic flow of vehicles passing through an intersection where roads having one or more lanes intersect, and the server device is equipped with a zone division unit that divides the intersection into a plurality of zones according to the shape of the intersection and the arrangement of entrances and exits at the intersection, a passing number calculation unit that calculates the number of vehicles that can simultaneously pass through a lane in each zone for each lane in each zone, a key package management unit that assigns keys that allow the vehicles to enter the lane in each zone, equal to the calculated number of vehicles, to each lane in each zone, and a key distribution unit that distributes the keys to the vehicles according to the vehicle's planned driving route at the intersection, and the vehicle drives according to the driving route when it receives the keys distributed from the server device. [Effects of the Invention]

[0008] According to the present invention, traffic flow at an intersection can be controlled at the lane level to allow vehicles to pass through the intersection efficiently. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the configuration of a traffic flow control system according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram showing an intersection targeted by a traffic flow control system. [Figure 3] FIG. 10 is a diagram showing a key package table. [Figure 4] FIG. 2 is a diagram illustrating an example of the operation of the traffic flow control system. [Figure 5] FIG. 2 is a diagram illustrating an example of the operation of the traffic flow control system. [Figure 6] FIG. 2 is a diagram illustrating an example of the operation of the traffic flow control system. [Figure 7] FIG. 2 is a diagram illustrating an example of the operation of the traffic flow control system. [Figure 8] FIG. 2 is a diagram illustrating an example of the operation of the traffic flow control system. [Figure 9] FIG. 2 is a diagram illustrating an example of the operation of the traffic flow control system. [Figure 10] 10 is a flowchart showing the operation of the server device regarding key distribution. [Figure 11] 4 is a flowchart showing the operation of a vehicle entering an intersection. [Figure 12] FIG. 1 is a diagram showing an intersection targeted by a traffic flow control system. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that components with the same reference numerals in each embodiment have the same functions in each embodiment unless otherwise specified, and description thereof will be omitted.

[0011] Fig. 1 is a diagram showing the configuration of a traffic flow control system 1 according to this embodiment. Fig. 2 is a diagram showing an intersection X1 that is a target of the traffic flow control system 1. Fig. 3 is a diagram showing a key package table.

[0012] The traffic flow control system 1 is a system having a server device 10 that controls the traffic flow of vehicles 20 passing through an intersection where roads having one or more lanes intersect. The intersection X1 targeted by the traffic flow control system 1 may be a roundabout or rotary intersection as shown in FIG. 2. The intersection X1 shown in FIG. 2 is a four-way intersection where four roads intersect with left-hand traffic. The road within the intersection X1 shown in FIG. 2 has two lanes. A vehicle 20 can enter the intersection X1 from any of the entrances P11 to P41 and exit from any of the exits P12 to P42 by traveling clockwise within the intersection X1. The shape of the intersection X1 is not limited to the shape shown in FIG. 2.

[0013] The server device 10 is a so-called cloud server, and is configured to include a processor, a memory, and a program. The processor executes the program stored in the memory, thereby realizing various functions of the server device 10. The server device 10 is connected to a vehicle 20 passing through an intersection X1 so as to be able to communicate wirelessly. The communication between the server device 10 and the vehicle 20 is performed via wireless communication equipment F installed at the intersection X1.

[0014] As shown in FIG. 1, the server device 10 includes a zone division unit 101, a passage number calculation unit 102, an upper limit time calculation unit 103, a key package management unit 104, a diagnosis unit 105, a driving route receiving unit 106, a judgment unit 107, a judgment result transmission unit 108, a key distribution unit 109, a passage information receiving unit 110, and a map DB 120.

[0015] The map DB 120 is a database that stores map information of at least the intersection X1 and its surroundings. The map information stored in the map DB 120 is preferably map information of a high-precision map.

[0016] The zone dividing unit 101 virtually divides the intersection X1 into a plurality of zones according to the shape of the intersection X1 and the arrangement of the entrances and exits at the intersection X1. In the example of Fig. 2, the zone dividing unit 101 divides the intersection X1 into four zones A to D according to the shape of the intersection X1 and the arrangement of the entrances P11 to P41 and exits P12 to P42 at the intersection X1. Zone A has an outer lane A1 and an inner lane A2. The same applies to the other zones B to D.

[0017] The passing number calculation unit 102 calculates, for each lane in each zone divided by the zone dividing unit 101, the number of vehicles that can simultaneously pass through each lane. Specifically, the passing number calculation unit 102 can calculate the number of vehicles that can simultaneously pass through each lane by dividing the length of each lane in each zone by the typical vehicle length of the vehicle 20 plus a margin. In the example of FIG. 2, the number of vehicles that can simultaneously pass through lane A1 is three, and the number of vehicles that can simultaneously pass through lane A2 is two.

[0018] The upper limit time calculation unit 103 calculates, for each lane in each zone, an upper limit time that is allowed as the time required to pass through each lane in each zone. Specifically, the upper limit time calculation unit 103 first calculates the time required to travel through each lane safely and without congestion by dividing the length of each lane in each zone by the vehicle speed of the vehicle 20 that is appropriate for traveling through each lane safely and without congestion. The upper limit time calculation unit 103 then calculates the above upper limit time by adding a margin to the total time of this calculated time and the waiting time for traffic lights at the entrance and exit of intersection X1.

[0019] The key package management unit 104 assigns keys, which are electronic information permitting the vehicle 20 to enter each lane in each zone, to each lane in each zone, in the same number as the number of vehicles calculated by the passing number calculation unit 102. In the example of FIG. 2, the number of vehicles that can simultaneously pass through lane A1 is three, so the key package management unit 104 assigns three keys, "A11," "A12," and "A13," to lane A1. Similarly, the number of vehicles that can simultaneously pass through lane A2 is two, so the key package management unit 104 assigns two keys, "A21" and "A22," to lane A2. In this embodiment, as shown in FIG. 2, a collection of all keys (A11 to A22) assigned to each lane in each zone that constitutes intersection X1 is also referred to as the "key package" of intersection X1.

[0020] Each key has three states: "unused state," "in use state," and "reserved state." The unused state is a state in which the key has not been distributed to the vehicle 20. The in use state is a state in which the key has been distributed to the vehicle 20 and the vehicle 20 has entered the lane corresponding to the key. The reserved state is a state in which the key has been distributed to the vehicle 20 but the vehicle 20 has not entered the lane corresponding to the key. The initial state of each key is the unused state.

[0021] The key package management unit 104 has a timer that counts down the upper limit time calculated by the upper limit time calculation unit 103 according to the elapsed time since the vehicle 20 entered each lane in each zone. This timer is provided for each key. The upper limit time calculated for each lane is set as the initial value of each timer. When the vehicle 20 enters a certain lane, the countdown of the timer corresponding to the key distributed to permit the vehicle 20 to enter the certain lane into which the vehicle 20 entered starts. When the vehicle 20 exits a certain lane, the countdown of the timer corresponding to the key distributed to permit the vehicle 20 to enter the certain lane into which the vehicle 20 exited stops and is reset. As shown in FIG. 3 , the key package management unit 104 has a key package table that stores the timer value, each key, and the status of each key in association with each other. The key package management unit 104 updates the status of each key and the timer value stored in the key package table in real time according to the status of key distribution to the vehicle 20 and the status of the vehicle 20 passing through each lane.

[0022] The diagnosis unit 105 diagnoses the occurrence of congestion at intersection X1. Specifically, the diagnosis unit 105 diagnoses the occurrence of congestion for each lane in each zone based on whether the elapsed time since the vehicle 20 entered each lane in each zone has reached the upper limit time calculated by the upper limit time calculation unit 103. In more detail, if the state of the key in question is in use and the value of the timer corresponding to the key has reached zero, the diagnosis unit 105 diagnoses that congestion has occurred in the lane corresponding to the key. On the other hand, if the state of the key in question is not in use or the value of the timer corresponding to the key has not reached zero, the diagnosis unit 105 diagnoses that congestion has not occurred in the lane corresponding to the key.

[0023] The driving route receiving unit 106 receives the driving route at the intersection X1 that the vehicle 20 plans to take from the vehicle 20. The driving route receiving unit 106 receives a request for delivery of a key transmitted from the vehicle 20 together with the driving route.

[0024] The determination unit 107 determines whether the vehicle 20 can pass through the intersection X1 according to the travel route received by the travel route receiving unit 106, based on the diagnosis result of the diagnosis unit 105. Specifically, the determination unit 107 determines, among lanes in each zone on the received travel route that the diagnosis unit 105 has diagnosed as having congestion, that lane as an impassable lane. The determination unit 107 determines, among lanes in each zone on the received travel route that the diagnosis unit 105 has diagnosed as not having congestion, that lane as a passable lane. Then, if the determination unit 107 has determined that all lanes on the received travel route are passable lanes, the determination unit 107 determines that the vehicle 20 can pass through the intersection X1 according to the received travel route. If the determination unit 107 has determined that any lane on the received travel route is an impassable lane, the determination unit 107 determines that the vehicle 20 cannot pass through the intersection X1 according to the received travel route. Furthermore, when it is determined that all lanes in a certain zone are impassable, the determining unit 107 determines that the certain zone is impassable.

[0025] The determination result transmission unit 108 transmits the determination result of the determination unit 107 to the vehicle 20. At this time, the determination result transmission unit 108 transmits the determination result of the determination unit 107 to the vehicle 20, including information on impassable lanes or zones that exist on the received driving route.

[0026] The key distribution unit 109 distributes a key to the vehicle 20 according to the planned driving route at the intersection X1 of the vehicle 20. The key distribution unit 109 distributes the key based on the determination result of the determination unit 107. Specifically, if the determination unit 107 determines that the vehicle 20 cannot pass through the intersection based on the received driving route, the key distribution unit 109 does not distribute the key to the vehicle 20. If the determination unit 107 determines that the vehicle 20 can pass through the intersection based on the received driving route, the key distribution unit 109 determines whether an unused key exists (is available) for each lane on the driving route. If an unused key exists in each lane (i.e., is available), the key distribution unit 109 distributes the unused key to the vehicle 20. If an unused key does not exist in each lane, the key distribution unit 109 notifies the vehicle 20 of that fact.

[0027] The passing information receiving unit 110 receives passing information indicating that the vehicle 20 has passed through each lane in each zone. The passing information includes at least one of entry information indicating that the vehicle 20 has entered a lane corresponding to the key distributed by the key distribution unit 109, and exit information indicating that the vehicle 20 has exited a lane corresponding to the key distributed by the key distribution unit 109. The entry information or exit information includes information on the key corresponding to the lane that the vehicle 20 has entered or exited. The passing information receiving unit 110 of this embodiment receives the passing information from the vehicle 20, but the passing information receiving unit 110 may also receive the passing information from a sensor or the like provided at the intersection X1.

[0028] The vehicle 20 is a vehicle capable of so-called autonomous driving. The vehicle 20 includes an on-board device (e.g., ECU) 21 configured to include a processor, a memory, and a program. The on-board device 21 realizes various functions of the on-board device 21 by the processor executing the program stored in the memory. The on-board device 21 is connected to the server device 10 so as to be able to communicate wirelessly.

[0029] The on-board device 21 of the vehicle 20 includes a position acquisition unit 201, a driving route creation unit 202, a driving route transmission unit 203, a key request unit 204, a judgment result confirmation unit 205, a key receiving unit 206, a key management unit 207, a key storage unit 208, an automatic driving control unit 209, a passing information transmission unit 210, and a map DB 220.

[0030] The map DB 220 is a database that stores map information of at least the intersection X1 and its surroundings. The map information stored in the map DB 220 is preferably high-precision map information.

[0031] The position acquisition unit 201 acquires the self-position of the vehicle 20 by using position information from a GNSS receiver, dead reckoning using DMI and IMU, scan matching using LiDAR and cameras, and the like.

[0032] The travel route creation unit 202 creates a travel route at the intersection X1 where the vehicle 20 is scheduled to travel, based on the map information stored in the map DB 220, the current position of the vehicle 20 acquired by the position acquisition unit 201, and information on the destination of the vehicle 20 input to a navigation device, etc. In this case, the travel route creation unit 202 creates the travel route before the vehicle 20 enters the intersection X1.

[0033] The travel route transmission unit 203 transmits the travel route created by the travel route creation unit 202 to the server device 10. At this time, the travel route transmission unit 203 transmits the travel route created before the vehicle 20 enters the intersection X1.

[0034] The key request unit 204 requests the server device 10 to deliver keys corresponding to each lane on the travel route. At this time, the key request unit 204 requests the delivery of the keys before the vehicle 20 enters the intersection X1.

[0035] The determination result confirmation unit 205 receives the determination result of the determination unit 107 transmitted from the server device 10 in response to a request for key distribution, and confirms the determination result. If the determination result confirms that the vehicle 20 can pass through the intersection based on the driving route, the vehicle 20 travels according to the driving route after receiving the key. If the determination result confirms that the vehicle 20 cannot pass through the intersection based on the driving route, the vehicle 20 can wait until the key is received, or can re-create the driving route using the driving route creation unit 202.

[0036] In response to the request, the key receiving unit 206 receives the key distributed from the server device 10. At this time, the key receiving unit 206 receives the distributed key before the vehicle 20 enters the intersection X1.

[0037] The key management unit 207 manages the keys received by the key reception unit 206. The key storage unit 208 stores the keys managed by the key management unit 207 in a non-volatile memory.

[0038] When the key receiving unit 206 receives the key, the automatic driving control unit 209 controls the vehicle 20 to enter the intersection X1 and drive autonomously according to the driving route.

[0039] The passage information transmission unit 210 transmits passage information indicating that the vehicle 20 has passed through each lane in each zone to the server device 10. The passage information includes at least one of entry information indicating that the vehicle 20 has entered a lane corresponding to a key managed by the key management unit 207 and exit information indicating that the vehicle 20 has exited a lane corresponding to a key managed by the key management unit 207. The entry information or exit information includes information on the key corresponding to the lane that the vehicle 20 has entered or exited. The entry information or exit information is created based on map information stored in the map DB 220, the vehicle's own position acquired by the position acquisition unit 201, and key information managed by the key management unit 207. The passage information transmission unit 210 transmits the passage information in real time when the vehicle 20 enters or exits a lane corresponding to a key managed by the key management unit 207.

[0040] Fig. 4 is a diagram illustrating an example of the operation of the traffic flow control system 1. Fig. 5 is a diagram illustrating an example of the operation of the traffic flow control system 1. Figs. 4 and 5 illustrate an example of the operation of the traffic flow control system 1 before the vehicle V0 enters the intersection X1.

[0041] As described above, when the determination unit 107 determines that the vehicle 20 can pass through an intersection based on the driving route received by the driving route receiving unit 106, and when an unused key exists (is available) in the key corresponding to each lane on the driving route, the key distribution unit 109 of the server device 10 distributes the unused key to the vehicle 20.

[0042] When a key is delivered, the key package management unit 104 sets the state of the delivered key to reserved. Thereafter, when passage information including entry information is received, the key package management unit 104 sets the state of the key corresponding to the lane indicated by the entry information to in use. That is, the key package management unit 104 sets the state of the key to reserved from the time the key is delivered until passage information including entry information for the lane corresponding to the key is received. Thereafter, when passage information including exit information is received, the key package management unit 104 sets the state of the key corresponding to the lane indicated by the exit information to unused.

[0043] In the example of Fig. 4, the driving route creation unit 202 of vehicle V0 creates a driving route R0 that enters intersection X1 from entrance P31, passes through lane C1 in zone C, lane C2 in zone C, lane D2 in zone D, and lane A1 in zone A in that order, and exits intersection X1 from exit P22. The driving route transmission unit 203 of vehicle V0 transmits the created driving route R0 to server device 10. The key request unit 204 of vehicle V0 requests server device 10 to distribute a key.

[0044] When the travel route R0 and the key request are received, the determination unit 107 of the server device 10 determines whether the travel route R0 allows the vehicle V0 to pass through the intersection X1. If it is determined that the vehicle V0 can pass through the intersection X1, the key distribution unit 109 of the server device 10 determines whether an unused key exists for each of the keys C11 to C13, C21 to C22, D21 to D22, and A11 to A13 corresponding to the lanes C1, C2, D2, and A1 on the travel route R0. In the example of FIG. 4, the keys C11 to C22 corresponding to the lanes C1 and C2 are unused, and the keys D21 and D22 corresponding to the lane D2 are unused. On the other hand, none of the keys A11 to A13 corresponding to the lane A1 are unused. Therefore, the key distribution unit 109 of the server device 10 notifies the vehicle V0 that no keys are available. The vehicle V0 waits until it receives the key.

[0045] As shown in FIG. 5, when vehicle V1 in lane A1 in zone A exits lane A1, the key package management unit 104 of the server device 10 sets the status of key A12 to an unused state. Since keys C11, C21, D21, and A12 corresponding to lanes C1, C2, D2, and A1 on travel route R0 are in an unused state, the key distribution unit 109 of the server device 10 distributes the keys C11, C21, D21, and A12 to vehicle V0. The key package management unit 104 of the server device 10 sets the status of the distributed keys C11, C21, D21, and A12 to a reserved state. Upon receiving the keys C11, C21, D21, and A12, vehicle V0 enters intersection X1.

[0046] Fig. 6 is a diagram illustrating an example of the operation of the traffic flow control system 1. Fig. 7 is a diagram illustrating an example of the operation of the traffic flow control system 1. Figs. 6 and 7 illustrate an example of the operation of the traffic flow control system 1 when a vehicle V0 is passing through an intersection X1.

[0047] 6, when the vehicle V0 enters the lane C1 corresponding to the key C11, the passage information transmitting unit 210 of the vehicle V0 transmits passage information including entry information indicating that the vehicle V0 has entered the lane C1 corresponding to the key C11 to the server device 10. When the passage information including the entry information is received, the key package management unit 104 of the server device 10 sets the state of the key C11 to an in-use state and starts the countdown of the timer corresponding to the key C11.

[0048] As shown in FIG. 7, when the vehicle V0 exits the lane C1 corresponding to the key C11, the passage information transmission unit 210 of the vehicle V0 transmits passage information including exit information indicating that the vehicle V0 has exited the lane C1 corresponding to the key C11 to the server device 10. When the key package management unit 104 of the server device 10 receives the passage information including the exit information, the key package management unit 104 sets the state of the key C11 to an unused state, stops the countdown of the timer corresponding to the key C11, and resets the timer. Furthermore, when the vehicle V0 enters the lane C2 corresponding to the key C21, the passage information transmission unit 210 of the vehicle V0 transmits passage information including entry information indicating that the vehicle V0 has entered the lane C2 corresponding to the key C21 to the server device 10. When the key package management unit 104 of the server device 10 receives the passage information including the entry information, the key package management unit 104 sets the state of the key C21 to an in-use state and starts the countdown of the timer corresponding to the key C21.

[0049] Fig. 8 is a diagram illustrating an example of the operation of the traffic flow control system 1. Fig. 8 illustrates an example of the operation of the traffic flow control system 1 when congestion occurs at the intersection X1 due to a stopped vehicle V0.

[0050] 8, when vehicle V0 encounters an accident while passing through lane C2 corresponding to key C21 and stops, the value of the timer corresponding to key C21 reaches zero. The diagnosis unit 105 of the server device 10 diagnoses that congestion has occurred in lane C2 corresponding to key C21. The key package management unit 104 of the server device 10 changes the status of keys D21 and A12, which were distributed simultaneously with key C21, from reserved to unused, and notifies vehicle V0 that the keys D21 and A12 will be collected.

[0051] Fig. 9 is a diagram illustrating an example of the operation of the traffic flow control system 1. Fig. 9 illustrates an example of the operation of the traffic flow control system 1 when it is determined that the vehicles V5 and V6 cannot pass through the intersection X1 based on the travel routes created by the vehicles V5 and V6.

[0052] In the example of FIG. 9, an accident occurs to vehicle V4 while passing through lane A1, causing congestion in lane A1. In the example of FIG. 9, vehicle V5 is attempting to pass through intersection X1 according to travel route R5, which enters intersection X1 from entrance P31, passes through lanes C1, C2, D2, and A1 in that order, and exits intersection X1 through exit P22. In this case, the determination unit 107 of server device 10 determines that vehicle V5 cannot pass through intersection X1 due to travel route R5. The key distribution unit 109 of server device 10 does not distribute keys to vehicle V5 even if the statuses of keys C11-C13, C21-C22, D21-D22, and A12-A13 corresponding to lanes C1, C2, D2, and A1 on travel route R5 are unused. Vehicle V5 can wait without entering intersection X1.

[0053] In the example of FIG. 9 , vehicle V6 is attempting to pass through intersection X1 according to travel route R6, which enters intersection X1 from entrance P41, passes through lane D1, lane A1, and lane B1 in this order, and exits intersection X1 from exit P32. In this case, the determination unit 107 of the server device 10 determines that vehicle V6 cannot pass through intersection X1 due to travel route R6. The key distribution unit 109 of the server device 10 does not distribute keys to vehicle V6 even if the statuses of keys D11-D13, A12-A13, and B11-B13 corresponding to lanes D1, A1, and B1 on travel route R6 are unused. The determination result transmission unit 108 of the server device 10 can transmit the determination result of the determination unit 107 to vehicle V6, including information about impassable lane A1 on travel route R6. Vehicle V6 can regenerate travel route R61 that does not enter intersection X1 and avoids impassable lane A1.

[0054] In this way, even if congestion occurs within the intersection X1, the traffic flow control system 1 can prevent the vehicle V5 from entering the intersection X1, or can make the vehicle V6 travel along a travel route R61 that avoids the lane where the congestion has occurred. Therefore, the traffic flow control system 1 can control the traffic flow at the intersection X1 at the lane level, allowing the vehicle 20 to pass through the intersection X1 efficiently.

[0055] FIG. 10 is a flowchart showing the operation of the server device 10 regarding key distribution.

[0056] In step S11, the server device 10 receives the driving route from the vehicle 20.

[0057] In step S12, the server device 10 determines whether the received travel route allows the vehicle 20 to pass through the intersection X1. If it is determined that the received travel route allows the vehicle 20 to pass through the intersection X1, the server device 10 proceeds to step S14. If it is determined that the received travel route does not allow the vehicle 20 to pass through the intersection X1, the server device 10 proceeds to step S13.

[0058] In step S13, the server device 10 transmits to the vehicle 20 the determination result that the vehicle 20 cannot pass through the intersection X1 based on the received travel route, together with information about the impassable lane or zone.

[0059] In step S14, the server device 10 determines whether or not an unused key exists (is available) for each lane on the travel route. If an unused key exists (is available), the server device 10 proceeds to step S15. If an unused key does not exist (is not available), the server device 10 proceeds to step S17.

[0060] In step S15, the server device 10 transmits to the vehicle 20 a determination result that the vehicle 20 can pass through the intersection X1 according to the received driving route, and distributes to the vehicle 20 each key corresponding to each lane on the driving route.

[0061] In step S16, the server device 10 sets the state of each key distributed to the vehicle 20 to a reserved state. After that, the server device 10 ends the operation shown in FIG.

[0062] In step S17, the server device 10 registers the vehicles 20 in a distribution order table. This distribution order table is a table that indicates the order in which reserved keys are to be distributed to the vehicles 20. This distribution order table may be managed by the key distribution unit 109 or the key package management unit 104 of the server device 10.

[0063] FIG. 11 is a flowchart showing the operation of the vehicle 20 when it enters an intersection.

[0064] In step S21, the vehicle 20 creates a driving route for the intersection X1.

[0065] In step S22, the vehicle 20 transmits the created driving route to the server device 10 and requests the server device 10 to distribute a key.

[0066] In step S23, the vehicle 20 receives the determination result of whether the vehicle 20 can pass through the intersection X1 according to the transmitted driving route, and confirms the determination result. If the determination result is that the vehicle 20 can pass through the intersection X1 according to the transmitted driving route, the vehicle 20 proceeds to step S23. If the determination result is that the vehicle 20 cannot pass through the intersection X1 according to the transmitted driving route, the vehicle 20 proceeds to step S24.

[0067] In step S24, the vehicle 20 re-creates a travel route based on the information on the non-passable lanes or zones included in the determination result. After that, the vehicle 20 proceeds to S22.

[0068] In step S25, upon receiving the key distributed from the server device 10, the vehicle 20 enters the intersection X1 according to the transmitted travel route.

[0069] In step S26, the vehicle 20 passes through each lane on the transmitted travel route while transmitting passage information to the server device 10 when entering or exiting each lane.

[0070] FIG. 12 is a diagram showing an intersection X2 that is a target of the traffic flow control system 1. As shown in FIG.

[0071] The intersection targeted by the traffic flow control system 1 is not limited to the intersection X1 shown in FIG. 2, but may also be, for example, the intersection X2 shown in FIG. 12. The intersection X2 shown in FIG. 12 is a four-way intersection where four roads with left-hand traffic intersect in a crisscross pattern. The road in the intersection X2 shown in FIG. 12 has one lane. A vehicle 20 can enter the intersection X2 from any of the entrances P11 to P41 and exit from any of the exits P12 to P42 by traveling clockwise through the intersection X2. The configuration and operation of the traffic flow control system 1 described above with reference to FIGS. 1 to 11 can also be applied to the case where the target intersection is the intersection X2 shown in FIG. 12.

[0072] That is, the traffic flow control system 1 divides the intersection X2 into multiple zones using the zone dividing unit 101, and calculates the number of vehicles that can simultaneously pass through the lanes in each zone using the passing number calculation unit 102. The traffic flow control system 1 then assigns keys to the lanes in each zone using the key package management unit 104, and manages the status of the keys using a key package table. The traffic flow control system 1 then determines using the determination unit 107 whether the vehicle 20 can pass through the intersection X2 based on the travel route from the vehicle 20, and distributes the key to the vehicle 20 entering the intersection X2 using the key distribution unit 109. Other configurations and operations of the traffic flow control system 1 described using FIGS. 1 to 11 can also be applied to the case where the intersection X2 shown in FIG. 12 is the target.

[0073] In the above embodiment, the vehicle 20 has been described as a vehicle capable of so-called autonomous driving, but the vehicle 20 is not limited to a vehicle capable of fully autonomous driving, and may be a vehicle that provides driving assistance to the driver. In this case, the vehicle 20 may be provided with a driving assistance control unit that controls the vehicle to provide driving assistance, instead of the autonomous driving control unit 209, and the driving assistance control unit may control the vehicle 20 so that the vehicle 20 enters an intersection after receiving the key.

[0074] As described above, the traffic flow control system 1 of this embodiment is a traffic flow control system including a server device 10 that controls the traffic flow of vehicles passing through an intersection where roads having one or more lanes intersect. The server device 10 includes a zone dividing unit 101 that divides the intersection into multiple zones based on the shape of the intersection and the layout of entrances and exits at the intersection, a passing number calculation unit 102 that calculates the number of vehicles that can simultaneously pass through each lane in each zone, a key package management unit 104 that assigns keys to each lane in each zone, the number of vehicles that allow the vehicle 20 to enter the lane in each zone, and a key distribution unit 109 that distributes the keys to the vehicle 20 based on the planned driving route at the intersection. Upon receiving the keys distributed from the server device 10, the vehicle 20 drives along the driving route.

[0075] As a result, the traffic flow control system 1 of this embodiment can control the number of vehicles within the intersection so that vehicles 20 entering the intersection can pass through the lanes in each zone without congestion. Moreover, the traffic flow control system 1 of this embodiment can control the number of vehicles within the intersection at the lane level. Therefore, the traffic flow control system 1 of this embodiment can control the traffic flow at the intersection at the lane level, allowing vehicles 20 to pass through the intersection efficiently.

[0076] Furthermore, in the traffic flow control system 1 of this embodiment, the server device 10 further includes an upper limit time calculation unit 103 that calculates, for each lane in each zone, an upper limit time allowed as the time required to pass through the lane in each zone, and a diagnosis unit 105 that diagnoses the occurrence of congestion at intersections. The diagnosis unit 105 diagnoses the occurrence of congestion for each lane in each zone based on whether the elapsed time since the vehicle 20 entered the lane in each zone has reached the upper limit time.

[0077] As a result, the traffic flow control system 1 of this embodiment can accurately diagnose whether congestion has occurred in each lane within each zone. Therefore, the traffic flow control system 1 of this embodiment can accurately control the number of vehicles within the intersection so that vehicles 20 entering the intersection can pass through the lanes within each zone without congestion. Therefore, the traffic flow control system 1 of this embodiment can accurately control traffic flow at the intersection at the lane level, allowing vehicles 20 to pass through the intersection more efficiently.

[0078] Furthermore, in the traffic flow control system 1 of this embodiment, the server device 10 further includes a driving route receiving unit 106 that receives from the vehicle a driving route at an intersection that the vehicle 20 plans to take, and a determination unit 107 that determines whether the vehicle 20 can pass through the intersection along the received driving route based on the diagnosis result of the diagnosis unit 105. A key distribution unit 109 distributes a key based on the determination result of the determination unit 107.

[0079] As a result, the traffic flow control system 1 of this embodiment can distribute a key after diagnosing that there is no congestion on the planned driving route at the intersection of the vehicle 20. Therefore, the traffic flow control system 1 of this embodiment can reliably control the traffic flow at the intersection so that the vehicle 20 that has entered the intersection can pass through the intersection without congestion. Therefore, the traffic flow control system 1 of this embodiment can more appropriately control the traffic flow at the intersection at the lane level, allowing the vehicle 20 to pass through the intersection more efficiently.

[0080] Furthermore, in the traffic flow control system 1 of this embodiment, the key package management unit 104 manages keys, the value of a timer that counts down an upper limit time according to the elapsed time since the vehicle entered a lane in each zone, and the state of the key, in association with one another. The state of the key includes an unused state in which the key has not been distributed to the vehicle 20, and an in-use state in which the key has been distributed to the vehicle 20 and the vehicle 20 has entered the lane corresponding to the key. If the key state is in-use and the timer value reaches zero, the diagnosis unit 105 diagnoses that congestion has occurred in the lane corresponding to the key, and if the key state is not in-use or the timer value has not reached zero, the diagnosis unit 105 diagnoses that congestion has not occurred in the lane corresponding to the key.

[0081] As a result, the traffic flow control system 1 of this embodiment can diagnose in real time at the lane level whether congestion has occurred at the intersection using a server device 10 installed at a remote location from the intersection, even if the traffic flow at the intersection is not actually monitored. Therefore, the traffic flow control system 1 of this embodiment can easily and accurately control traffic flow at the intersection in real time so that vehicles 20 entering the intersection can pass through the lanes in each zone without congestion. Therefore, the traffic flow control system 1 of this embodiment can accurately and quickly control traffic flow at the intersection at the lane level, allowing vehicles 20 to pass through the intersection more efficiently.

[0082] Furthermore, in the traffic flow control system 1 of this embodiment, the server device 10 further includes a passage information receiving unit 110 that receives passage information including at least one of entry information indicating that the vehicle 20 has entered a lane corresponding to the distributed key and exit information indicating that the vehicle 20 has exited a lane corresponding to the distributed key. If the received passage information includes entry information, the key package management unit 104 sets the state of the key corresponding to the lane indicated by the entry information to an in-use state, and if the received passage information includes exit information, sets the state of the key corresponding to the lane indicated by the exit information to an unused state.

[0083] As a result, the traffic flow control system 1 of this embodiment can grasp the process of vehicles 20 passing through the intersection at the lane level in real time using the server device 10 installed at a remote location from the intersection, even if the traffic flow at the intersection is not actually monitored. Therefore, the traffic flow control system 1 of this embodiment can easily and accurately control the traffic flow at the intersection in real time so that vehicles 20 entering the intersection can pass through the lanes in each zone without congestion. Therefore, the traffic flow control system 1 of this embodiment can accurately and quickly control the traffic flow at the intersection at the lane level, allowing vehicles 20 to pass through the intersection more efficiently.

[0084] Furthermore, in the traffic flow control system 1 of this embodiment, the state of the key further includes a reserved state in which a key has been distributed to the vehicle 20 but the vehicle 20 has not entered the lane corresponding to the key. When the determination unit 107 determines that the vehicle 20 can pass through an intersection based on the travel route received from the vehicle 20 and there is an unused key corresponding to each lane on the travel route, the key distribution unit 109 distributes the unused key to the vehicle 20. The key package management unit 104 sets the state of the key to the reserved state from the time the key is distributed until passage information including entry information for the lane corresponding to the key is received.

[0085] As a result, the traffic flow control system 1 of this embodiment can prevent other vehicles 20 from cutting in and entering each lane on the travel route that has been determined to allow the vehicle 20 to pass through the intersection. Therefore, the traffic flow control system 1 of this embodiment can reliably control the traffic flow at the intersection so that the vehicle 20 that has entered the intersection can pass through the intersection without congestion. Therefore, the traffic flow control system 1 of this embodiment can more appropriately control the traffic flow at the intersection at the lane level, allowing the vehicle 20 to pass through the intersection more efficiently.

[0086] Furthermore, in the traffic flow control system 1 of this embodiment, the vehicle 20 is equipped with a driving route creation unit 202 that creates a driving route at an intersection where the vehicle 20 is scheduled to travel, a driving route transmission unit 203 that transmits the created driving route to the server device 10, a key request unit 204 that requests the server device 10 to distribute keys corresponding to lanes on the transmitted driving route, a key receiving unit 206 that receives the keys distributed from the server device 10 in response to the request, and an automatic driving control unit 209 that, when the keys are received, controls the vehicle 20 to travel autonomously according to the driving route.

[0087] As a result, the traffic flow control system 1 of this embodiment can reliably cause the vehicle 20 to travel along a travel route that has been determined to allow the vehicle 20 to pass through the intersection. Therefore, the traffic flow control system 1 of this embodiment can reliably control the traffic flow at the intersection so that the vehicle 20 that has entered the intersection can pass through the intersection without congestion. Therefore, the traffic flow control system 1 of this embodiment can more appropriately control the traffic flow at the intersection at the lane level, allowing the vehicle 20 to pass through the intersection more efficiently.

[0088] Furthermore, in the traffic flow control system 1 of this embodiment, the driving route transmission unit 203 transmits a driving route before the vehicle 20 enters an intersection, the key request unit 204 requests delivery of a key before the vehicle 20 enters the intersection, the key receiving unit 206 receives the key before the vehicle 20 enters the intersection, and the automatic driving control unit 209 controls the vehicle 20 to enter the intersection when the key is received.

[0089] As a result, the traffic flow control system 1 of this embodiment can prevent the vehicle 20 from entering the intersection before receiving the key. Therefore, the traffic flow control system 1 of this embodiment can reliably control the number of vehicles in the intersection to a number that allows vehicles 20 to pass through the intersection without congestion, and can reliably control the traffic flow at the intersection so that vehicles 20 that have entered the intersection can pass through the intersection without congestion. Therefore, the traffic flow control system 1 of this embodiment can more appropriately control the traffic flow at the intersection at the lane level, allowing vehicles 20 to pass through the intersection more efficiently.

[0090] Furthermore, in the traffic flow control system 1 of this embodiment, the vehicle 20 further includes a determination result confirmation unit 205 that confirms the determination result of the determination unit 107 transmitted in response to a request for key distribution. The travel route creation unit 202 recreates the travel route when the determination result confirms that the vehicle 20 cannot pass through the intersection due to the travel route.

[0091] As a result, the traffic flow control system 1 of this embodiment can recreate a driving route that can pass through an intersection, and if there are unused keys corresponding to each lane on the driving route, the vehicle 20 can immediately travel along the recreated driving route without having to wait for a while. Therefore, the traffic flow control system 1 of this embodiment can control the traffic flow at an intersection so that the vehicle 20 that has entered the intersection can pass through the intersection efficiently without congestion. Therefore, the traffic flow control system 1 of this embodiment can more appropriately control the traffic flow at the intersection at the lane level, allowing the vehicle 20 to pass through the intersection more efficiently.

[0092] Furthermore, in the traffic flow control system 1 of this embodiment, the vehicle 20 further includes a passage information transmitting unit 210 that transmits passage information to the server device 10, the passage information including at least one of entry information indicating that the vehicle 20 has entered the lane corresponding to the received key and exit information indicating that the vehicle 20 has exited the lane corresponding to the received key.

[0093] As a result, the traffic flow control system 1 of this embodiment can grasp the process of the vehicle 20 passing through the intersection at the lane level in real time. Therefore, the traffic flow control system 1 of this embodiment can easily and accurately control the traffic flow at the intersection in real time so that the vehicle 20 entering the intersection can pass through the lanes in each zone without congestion. Therefore, the traffic flow control system 1 of this embodiment can accurately and quickly control the traffic flow at the intersection at the lane level, allowing the vehicle 20 to pass through the intersection more efficiently.

[0094] The present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations.

[0095] Furthermore, the above-mentioned configurations, functions, processing units, processing means, etc. may be partly or entirely realized by hardware, for example, by designing them as integrated circuits. The above-mentioned configurations, functions, etc. may also be realized by software, in which a processor interprets and executes a program that realizes each function. Information such as programs, tapes, and files that realize each function may be stored in a memory, a hard disk, an SSD (solid state drive), etc. The image data can be stored in a recording device, or on a recording medium such as an IC card, SD card, or DVD.

[0096] In addition, the control lines and information lines shown are those that are considered necessary for the explanation, and do not necessarily show all the control lines and information lines in the product. In reality, it can be assumed that almost all components are interconnected. [Explanation of symbols]

[0097] 1...traffic flow control system, 10...server device, 101...zone division unit, 102...passing number calculation unit, 103...upper limit time calculation unit, 104...key package management unit, 105...diagnosis unit, 106...driving route receiving unit, 107...judgment unit, 109...key distribution unit, 110...passing information receiving unit, 20...vehicle, 202...driving route creation unit, 203...driving route transmission unit, 204...key request unit, 205...judgment result confirmation unit, 206...key receiving unit, 209...automatic driving control unit, 210...passing information transmission unit, A to D...zone, A1 to D2...lane, A11 to D22...key, P11 to P41...entrance, P12 to P42...exit, X1, X2...intersection

Claims

1. A traffic flow control system having a server device that controls traffic flow of vehicles passing through an intersection where roads having one or more lanes intersect, The server device a zone dividing unit that divides the intersection into a plurality of zones according to a shape of the intersection and an arrangement of entrances and exits at the intersection; a passing number calculation unit that calculates the number of vehicles that can simultaneously pass through a lane in each zone for each lane in the zone; a key package management unit that allocates keys that permit the vehicles to enter the lanes in each zone to the calculated number of vehicles, for each of the lanes in each of the zones; a key distribution unit that distributes the key to the vehicle in accordance with a planned driving route of the vehicle at the intersection; an upper limit time calculation unit that calculates an upper limit time that is allowed as a time required to pass through the lane in each of the zones, for each of the lanes in each of the zones; a diagnosis unit that diagnoses a congestion occurrence state at the intersection, the diagnosing unit diagnoses the congestion occurrence state at the intersection for each lane in each zone based on whether or not an elapsed time since the vehicle entered the lane in each zone has reached the upper limit time; When the vehicle receives the key distributed from the server device, the vehicle travels along the travel route. A traffic flow control system characterized by:

2. The server device a travel route receiving unit that receives from the vehicle the travel route at the intersection that the vehicle plans to travel; a determination unit that determines whether the vehicle can pass through the intersection along the received travel route based on a diagnosis result of the diagnosis unit, The key distribution unit distributes the key based on the determination result of the determination unit.

2. The traffic flow control system according to claim 1.

3. the key package management unit manages the key, a value of a timer that counts down the upper limit time in accordance with the elapsed time, and a state of the key in association with one another; The state of the key includes an unused state in which the key has not been distributed to the vehicle, and an in-use state in which the key has been distributed to the vehicle and the vehicle has entered the lane corresponding to the key; The diagnostic unit If the state of the key is the in-use state and the value of the timer reaches zero, it is diagnosed that the congestion has occurred in the lane corresponding to the key; If the state of the key is not in the in-use state or the value of the timer has not reached zero, it is diagnosed that the congestion has not occurred in the lane corresponding to the key.

3. The traffic flow control system according to claim 2.

4. the server device further includes a passage information receiving unit that receives passage information including at least one of entry information indicating that the vehicle has entered the lane corresponding to the distributed key and exit information indicating that the vehicle has exited the lane corresponding to the distributed key; The key package management unit If the received passing information includes entry information, setting the state of the key corresponding to the lane indicated by the entry information to the in-use state; If the received passage information includes exit information, the state of the key corresponding to the lane indicated by the exit information is set to the unused state.

4. The traffic flow control system according to claim 3.

5. The key status further includes a reserved status in which the key has been distributed to the vehicle but the vehicle has not entered the lane corresponding to the key; the key distribution unit distributes the unused key to the vehicle when the determination unit determines that the vehicle can pass through the intersection based on the travel route received from the vehicle and when an unused key exists in the key corresponding to each lane on the travel route; The key package management unit sets the state of the key to the reserved state from the time the key is distributed until the time the passage information including the entry information for the lane corresponding to the key is received.

5. The traffic flow control system according to claim 4.

6. The vehicle is a travel route creation unit that creates the travel route at the intersection where the vehicle is scheduled to travel; a travel route transmission unit that transmits the created travel route to the server device; a key request unit that requests the server device to distribute the key corresponding to the lane on the transmitted travel route; a key receiving unit that receives the key distributed from the server device in response to the request; an automatic driving control unit that, when the key is received, controls the vehicle to travel autonomously along the travel route.

3. The traffic flow control system according to claim 2.

7. the travel route transmission unit transmits the travel route before the vehicle enters the intersection; the key request unit requests delivery of the key before the vehicle enters the intersection; the key receiving unit receives the key before the vehicle enters the intersection; The automatic driving control unit controls the vehicle to enter the intersection when the key is received.

7. The traffic flow control system according to claim 6.

8. the vehicle further includes a determination result confirmation unit that confirms the determination result of the determination unit transmitted in response to the request, The travel route creation unit recreates the travel route when the determination result indicates that the vehicle cannot pass through the intersection according to the travel route.

7. The traffic flow control system according to claim 6.

9. The vehicle further includes a passage information transmitting unit that transmits passage information to the server device, the passage information including at least one of entry information indicating that the vehicle has entered the lane corresponding to the received key and exit information indicating that the vehicle has exited the lane corresponding to the received key.

7. The traffic flow control system according to claim 6.

Images