Signal control system

Abstract

To provide a new method on signal control of an intersection on which an automatic operation automobile travels.SOLUTION: A signal control system 1 for performing signal control of a predetermined intersection in a road network on which an automatic operation automobile 10 travels performs: determining by each approach lane, a vehicle group 20 consisting of one or more automobiles intending to approach the intersection from the same approach lane based on travel information 32 received from the automobile 10; determining an arrival schedule time of the vehicle group 20 at the intersection; setting an only one permitted approach lane and approach permission period by which an approach to the intersection is permitted on a given time axis for each vehicle group 20; managing a signal corresponding to a time passage by treating the whole approach lanes as a stop signal during a period other than the approach permission period; and generating signal management information 34 based on the management contents so as to notify the automobile 10 of the information.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a signal control system for an intersection. [Background technology]

[0002] At intersections, traffic signal control is performed to control the operation of traffic lights in order to ensure smooth traffic flow. As one type of traffic signal control, priority control is known, which changes signal control parameters to give priority to specific vehicles, such as public vehicles such as route buses (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-115123 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, technological developments have been made for autonomous vehicles that can travel autonomously. At intersections where autonomous vehicles travel, it is desirable to have a means of notifying the vehicle of traffic signal information in addition to the traffic lights installed at conventional intersections so that the vehicle can recognize traffic signal information related to the intersection. In addition, autonomous vehicles have the characteristic of being able to control the direction and speed of travel without human intervention. If all vehicles passing through an intersection are autonomous, it would be convenient to realize a new signal control that allows vehicles to pass through the intersection more smoothly and efficiently than before, and this would also be meaningful for the spread of autonomous vehicles.

[0005] The problem that the present invention aims to solve is to provide a new method for signal control at intersections where autonomous vehicles pass through. [Means for solving the problem]

[0006] The first invention for solving the above problem is: A signal control system that controls signals at a predetermined intersection where an autonomous vehicle runs, the vehicle is equipped with a communication control device that communicates with the signal control system, and an entrance control device that controls entrance to the intersection based on given signal management information received from the signal control system; A driving information acquisition means (for example, the driving information acquisition unit 202 in FIG. 11) for acquiring driving information from the vehicle; A determination means (e.g., the determination unit 204 in FIG. 11 ) that determines a vehicle group consisting of one or more vehicles that are scheduled to enter the intersection from the same entrance road based on the travel information, and determines an expected arrival time of the vehicle group at the intersection, for each entrance road; a signal management means (e.g., the signal management unit 206 in FIG. 11 ) for managing signals according to the passage of time by setting, for each vehicle group, a unique permitted approach direction and an approach permission period for permitting entry into the intersection on a given time axis based on a determination result of the determination means, and treating all approach directions as stop signals during periods other than the relevant approach permission period; A notification control means (for example, the notification control unit 208 in FIG. 11) that generates the signal management information based on the management contents by the signal management means and controls to notify the vehicle of the information; The signal control system is provided with the following.

[0007] According to the first invention, a new method of signal control at an intersection where autonomous vehicles run can be provided. In other words, a unique permitted approach and an approach permission period that permits entry for each group of vehicles that are scheduled to enter the intersection from the same approach are set on a given time axis, and all approach directions are treated as stop signals during periods other than the approach permission period, thereby performing a completely new intersection signal control that is completely different from the conventional one. Since the route permitted to enter the intersection is set to a maximum of one route, and vehicles are allowed to enter the intersection in groups of vehicles, it is possible to avoid crossing of driving directions between vehicles at the intersection, suppress congestion, and realize smooth and efficient traffic flow. Furthermore, signal management information based on the management contents of the signal at the intersection is notified to each vehicle, so that autonomous vehicles can control their entry into the intersection according to the set permitted approach and approach permission period.

[0008] The second invention is the above-mentioned invention, the signal management means sets the entry permission period by setting an entry route through which the vehicle group enters as the permitted entry route so that the entry permission periods for the vehicle group do not overlap, The notification control means notifies the vehicle group by including information on the entry permission period set for the vehicle group in the signal management information. It is a signal control system.

[0009] According to the second aspect of the present invention, the entry permission periods for each vehicle group are set so as not to overlap, which makes it possible to perform signal control such that each vehicle group has exclusive access to the intersection.

[0010] The third invention is the above-mentioned invention, the signal management means sets the entry permission period on the time axis by allocating the entry permission period in order from the vehicle group having the earliest scheduled arrival time. It is a signal control system.

[0011] According to the third aspect of the present invention, the entry permission period is set by allocating the period in order of the vehicles that are scheduled to arrive at the intersection first. This allows the entry permission period to be allocated in order of the vehicles that arrive at the intersection first, thereby shortening the time that each vehicle is stopped after arriving at the intersection and unable to enter, thereby enabling signal control that suppresses congestion at the intersection.

[0012] The fourth aspect of the present invention is the above-mentioned invention, The determination means determines, for each of the vehicle groups, an ideal passing period through the intersection starting from the estimated arrival time based on the travel information, the signal management means sets the entry permission period for each vehicle group based on the ideal passing period. It is a signal control system.

[0013] According to the fourth aspect of the present invention, an ideal passing period starting from the estimated arrival time is determined, and an entry permission period is set based on this ideal passing period. The ideal passing period can be set as a period during which the vehicle group can enter and pass the intersection without stopping before the intersection. This enables signal control based on the ideal passing period to reduce the time that each vehicle is stopped after arriving at the intersection and unable to enter, thereby suppressing congestion at the intersection.

[0014] The fifth invention is the above-mentioned invention, the signal management means, when there are vehicle groups whose ideal passing periods overlap, divides the ideal passing periods of one or both of the overlapping vehicle groups, and sets the entry permission periods corresponding to the divided ideal passing periods, respectively. It is a signal control system.

[0015] According to the fifth aspect of the invention, the ideal passing period of one or both of the overlapping vehicle groups is divided, and an entry permission period corresponding to each divided ideal passing period is set. When the number of vehicles constituting the vehicle group is large and the length of the ideal passing period is long, the time that the other vehicle groups with the overlapping ideal passing periods have to stop without being able to enter the intersection after arriving at the intersection will be long. In such a case, by dividing the ideal passing period that overlaps between the vehicle groups, it is possible to set the entry permission period to be allocated alternately between the vehicle groups, which reduces the bias between the vehicle groups in the time that the vehicle groups have to stop without being able to enter the intersection after arriving at the intersection, thereby reducing the sense of unfairness, and enables signal control that suppresses congestion at the intersection.

[0016] The sixth aspect of the present invention is the above-mentioned invention, the signal management means sets the ideal passing period or the entry permission period after division to be equal to or longer than a predetermined minimum time length; It is a signal control system.

[0017] According to the sixth aspect of the present invention, the ideal passing period or the entry permission period is set to a predetermined minimum time length or more. This ensures that the time required for a group of vehicles to enter and pass through an intersection is at least the minimum time, thereby enabling signal control that ensures safety at the intersection. [Brief description of the drawings]

[0018] [Figure 1] An example of a signal control system application. [Diagram 2] An explanatory diagram of intersection signal control. [Diagram 3] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 4] FIG. 13 is an explanatory diagram of the setting of entry permission. [Diagram 5] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 6] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 7] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 8] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 9] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 10] FIG. 13 is an explanatory diagram of the setting of entry permission. [Figure 11] An example of the functional configuration of a signal control system. [Figure 12] An example of data on a group of vehicles scheduled to enter. [Figure 13] 13 is an example of entry permission setting data. [Figure 14] 4 is a flowchart of a signal control process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Note that the form to which the present invention can be applied is not limited to the following embodiments. In addition, in the description of the drawings, the same elements are given the same reference numerals.

[0020] [Signal Control System] 1 is a diagram showing an application example of a signal control system 1 according to the present embodiment. The signal control system 1 according to the present embodiment is a system that performs signal control at a predetermined intersection in a road network on which autonomously driven automobiles travel. The signal control system 1 performs signal control at the intersection by communicating with automobiles 10 traveling on the roads via wireless base stations 3 installed at various locations so that the communication range includes the entire road network to be controlled.

[0021] Specifically, the signal control system 1 receives driving information 32 from each automobile 10. The driving information 32 is information related to the driving of the automobile 10, and includes the driving position, driving speed, driving direction, etc., associated with the automobile ID of the automobile 10. The latest information on this driving information 32 is generated by the automobile 10 and transmitted at a predetermined time interval.

[0022] The signal control system 1 manages the intersection's signals by setting a unique permitted approach route and an approach permission period that permits entry into the intersection based on the received travel information 32 of each automobile 10, and treating all approach routes as stop signals during periods other than the approach permission period. Then, signal management information 34 based on the management contents of the signals is generated and notified to each automobile 10. The signal management information 34 is information regarding the entry permission of the automobile 10 into the intersection that is generated for each automobile 10, and includes the intersection ID of the intersection, the permitted approach route that is the route that is permitted to enter the intersection, and the progress permission period that is the period, in association with the automobile ID of the automobile 10.

[0023] The automobile 10 is equipped with a communication control device 12 that performs wireless communication with the signal control system 1 via a wireless base station 3, and a driving control device 14 that has a driving control function by automatic driving. The functions of the driving control device 14 include a function of controlling entry into an intersection based on signal management information 34 received from the signal control system 1. Specifically, as the entry control, when the driving direction of the vehicle matches the permitted entry route and is within the entry permission period, the driving is controlled so that the vehicle enters the intersection from the permitted entry route. When the driving direction does not match the permitted entry route or is outside the entry permission period, the driving is controlled so that the vehicle does not enter the intersection. In other words, the driving control device 14 can be said to be an entry control device that performs entry control into an intersection based on the signal management information 34 received from the signal control system 1. In addition, in this embodiment, the driving control function of the driving control device 14 is described as including a known function that realizes driving control such as collision prevention and vehicle distance maintenance by image recognition of other traveling vehicles based on images captured by an on-board camera, etc. In this embodiment, a planned driving route is set in advance in the driving control device 14, and the driving control device 14 controls the driving of the vehicle (the automobile 30) along the planned driving route.

[0024] [Intersection signal control] FIG. 2 is a diagram illustrating signal control of an intersection by the signal control system 1. FIG. 2 shows an example of a cross intersection having four entry routes A to D. The signal control system 1 assigns entry permission (corresponding to a green light) to automobiles 10 that are scheduled to enter the intersection for each vehicle group 20. That is, for each vehicle group 20, an allowed entry route that is a route that the vehicle group 20 is permitted to enter and an entry permission period that is a period during which entry is permitted are set. In addition, the entry permission periods for each vehicle group 20 are set on the same time axis so that they do not overlap with each other. Then, the intersection signals are managed by treating all entry routes as stop signals during periods other than the entry permission period.

[0025] A "vehicle group 20" is a collection of one or more automobiles 10 that are scheduled to enter an intersection from the same entrance route. "Scheduled to enter an intersection" means that the vehicle group 20 is traveling in the direction of entering the intersection and the distance from the vehicle group 20 to the intersection is within a predetermined distance. In FIG. 2, the distance that is considered to be scheduled to enter an intersection is shown as a target range in the shape of a dashed circle centered on the intersection. A vehicle group 20 whose leading automobile is located within this target range is determined to be "scheduled to enter an intersection." In the example of FIG. 2, vehicle groups 20a to 20d are scheduled to enter from four routes A to D, respectively.

[0026] 3 to 7 are diagrams for explaining the setting of entry permission to an intersection by the signal control system 1. As shown in Fig. 3, the signal control system 1 first determines a group of vehicles 20 that are scheduled to enter the intersection for each entry route of the intersection, based on the travel information 32 received from each automobile 10. In the example of Fig. 3, groups of vehicles 20a to 20d are scheduled to enter the intersection from four routes A to D, respectively.

[0027] Next, as shown in Fig. 4, for each vehicle group 20, an estimated arrival time at the intersection is calculated from the distance to the intersection. The "distance" to the intersection can be, for example, the distance from the front position of the front vehicle of the vehicle group 20 to a predetermined position at the intersection (for example, the position of the stop line). Then, a required time to reach the intersection is calculated from the distance to the intersection and the traveling speed of the vehicle group, and the time after the required time has elapsed from the reference time corresponding to the calculated timing is set as the estimated arrival time at the intersection. The traveling speed of the vehicle group 20 may be, for example, a speed included in the traveling information 32, or may be a speed that is determined in advance because the automobile 10 is autonomous.

[0028] Furthermore, the signal control system 1 determines an ideal passing period for the intersection from the length of each vehicle group 20. The "vehicle group length" may be determined, for example, by adding a predetermined margin distance to the distance from the leading position of the leading vehicle in the vehicle group 20 to the rearmost position of the rearmost vehicle in the vehicle group 20, or may be determined according to the number of vehicles constituting the vehicle group 20. In other words, the ideal passing period is set to a period of time that begins with the scheduled arrival time of the vehicle group 20 at the intersection and has a length according to the vehicle group length. Note that it is desirable for the ideal passing period to be equal to or longer than a predetermined minimum time length that allows the vehicle 30 to safely enter and pass through the intersection.

[0029] Then, the signal control system 1 sets an entry permission period for the intersection based on the ideal passing period for each vehicle group 20. At this time, the entry permission periods are set so that the entry permission periods of the vehicle groups 20 do not overlap and are allocated in order of the earliest scheduled arrival time at the intersection.

[0030] Specifically, as shown in FIG. 5, when the ideal passing periods of the vehicle groups 20 do not overlap with each other, the signal control system 1 sets the ideal passing periods as the entry permitted periods. FIG. 5 shows an example of a case where the ideal passing periods of the vehicle groups do not overlap. In the example of FIG. 5, two vehicle groups 20e, 20f are scheduled to enter an intersection, and their ideal passing periods Ie, If do not overlap. Therefore, the ideal passing periods Ie, If of the vehicle groups 20e, 20f are set as the entry permitted periods Te, Tf starting from the estimated arrival times te, tf as they are. Note that periods other than the entry permitted periods are set as periods (entry prohibited periods) in which entry is not permitted (stop signal) for all entry routes.

[0031] On the other hand, when the ideal passing periods of the vehicle groups 20 overlap, as shown in FIG. 6, the signal control system 1 sets the entry permission period of the same time length as the ideal passing period in the order of the earliest scheduled arrival time at the intersection. FIG. 6 shows an example of the case where the ideal passing periods of the vehicle groups 20 overlap. In the example of FIG. 6, two vehicle groups 20g and 20h are scheduled to enter the intersection, and their ideal passing periods Ig and Ih overlap. Therefore, first, the ideal passing period Ig of the vehicle group 20g with the earlier scheduled arrival time tg or th is set as the entry permission period Tg with the scheduled arrival time tg as the start time. After that, an entry non-permission period in which all entry routes are set as a stop signal is set, and an entry permission period Th with the same time length as the ideal passing period Ih of the vehicle group 20h with the later scheduled arrival time tg or th is set.

[0032] In addition, when the ideal passing periods of the vehicle groups 20 overlap each other and the time length of the overlapping ideal passing periods is relatively "long", as shown in FIG. 7, the signal control system 1 divides the ideal passing period and sets the entry permission period based on the divided period. FIG. 7 shows an example of a case where the ideal passing periods of the vehicle groups 20 overlap each other and the ideal passing period is divided. When dividing the ideal passing period of the vehicle group 20, the period is divided so that the time length of the divided period (divided period) is equal to or longer than a predetermined minimum time length. In other words, it can be said that the ideal passing period is divisible when the time length (divisible time length) is equal to or longer than twice the minimum time length. This minimum time length can be set to, for example, a time length that allows the automobile 30 to safely enter and pass through the intersection. Then, the entry permission period is set based on the ideal passing period of each vehicle group 20 or a period (divided period) obtained by dividing the ideal passing period so that the vehicles travel in order of their scheduled arrival time at the intersection.

[0033] If the ideal passing period of a certain vehicle group 20 is long, other vehicle groups 20 with overlapping ideal passing periods cannot enter the intersection for a long time, which creates a sense of unfairness. The ideal passing period is divided to reduce this sense of unfairness. However, if the ideal passing period is divided, the corresponding vehicle groups 20 are cut off midway by passing through the intersection, so in order to prevent the vehicle groups 20 from being cut off more than necessary, the divided period is set to be equal to or longer than a predetermined minimum time length.

[0034] In the example of FIG. 7, two vehicle groups 20m and 20n are scheduled to enter the intersection, and their ideal passing periods overlap. In addition, the ideal passing periods Im and In of the vehicle groups 20m and 20n are both equal to or greater than the divisible time length and can be divided. Therefore, the ideal passing periods Im and In of the vehicle groups 20m and 20n are both divided into two periods. Since the expected arrival times tm and tn of the vehicle groups 20m and 20n are earlier in that order, the entry permission periods are set in the following order: the entry permission period Tm1 based on the first divided period Im1 of the vehicle group 20m, the entry permission period Tn1 based on the first divided period In1 of the vehicle group 20n, the entry permission period Tm2 based on the second divided period Im2 of the vehicle group 20m, and the entry permission period Tn2 based on the second divided period In2 of the vehicle group 20n. Except for the entry permission periods, an entry non-permission period is set.

[0035] 7, the entry permission period is set to have the same time length as the period (divided period) into which the ideal passing period is divided, but the entry permission period may be set to be longer than the time length of the divided period. This is because, since the vehicle group is divided to pass through the intersection by dividing the ideal passing period, it is taken into consideration that the latter half of the vehicle group 10 will stop before the intersection.

[0036] Since the position and speed of the automobile 10 change from moment to moment, the signal control system 1 repeats the determination of the vehicle group 20 and the setting of the entry permission period at a predetermined cycle. The entry permission period may be set (reset) for all vehicle groups 20 scheduled to enter the intersection each time. However, since the automobile 10 is an autonomous driving automobile and the traveling speed is stably controlled, and from the viewpoint of safety, the entry permission period already set for the vehicle group 20 may not be reset (updated) in principle, and an entry permission period may be additionally set for a vehicle group 20 determined to be newly scheduled to enter the intersection. In this case, the entry permission period is reset as necessary for the vehicle group 20 that overlaps with the ideal passing period of the new vehicle group 20.

[0037] 8 to 10 are diagrams for explaining the setting of the entry permission period for a vehicle group 20 that is scheduled to newly enter an intersection. Like FIG. 3, FIG. 8 shows an example of a cross intersection having four entry routes A to D. In the previous setting (reference time t0), the planned entry periods were set for vehicle groups 20p to 20s that are scheduled to enter the intersection from each of the entry routes A to D. Then, in the current setting (reference time t1), a new vehicle group 20t is scheduled to enter the intersection from the entry route A, and an entry permission period is set for this vehicle group 20t.

[0038] First, as shown in Fig. 9, for a new vehicle group 20t, an estimated arrival time is calculated from the distance to the intersection. Also, an ideal passing period for the intersection is calculated from the length of the vehicle group. Then, based on this ideal passing period, the entry permission period of the new vehicle group 20t is set so as not to overlap with the entry permission periods of the other vehicle groups 20p to 20s that have already been set.

[0039] That is, if the ideal passing period of the new vehicle group 20t does not overlap with any of the already set entry permission periods of the other vehicle groups 20p to 20s, the ideal passing period of the vehicle group 20t is set as the entry permission period as is.

[0040] On the other hand, if the ideal passing period of the new vehicle group 20t overlaps with any of the entry permission periods of the other vehicle groups 20, the divisible ideal passing periods of the new vehicle group 20t and the overlapping other vehicle groups 20 are divided to set (reset) the entry permission periods of each of these vehicle groups 20. Then, the entry permission periods are set (reset) based on the ideal passing period of each vehicle group 20 or a period obtained by dividing the ideal passing period, so that the vehicle groups 20 move around in order of the earliest scheduled arrival time at the intersection.

[0041] In the example of Fig. 9, the ideal passing period of the new vehicle group 20t overlaps with the entry permission periods of the other vehicle groups 20r and 20s that have already been set. As shown in Fig. 10, the ideal passing period Ir of the vehicle group 20r is less than the divisible time length and cannot be divided. On the other hand, the ideal passing period Is of the vehicle group 20s is equal to or greater than the divisible time length and is divided into two periods Is1 and Is2. The ideal passing period It of the vehicle group 20t is also equal to or greater than the divisible time length and is divided into two periods It1 and It2.

[0042] Since the vehicle groups 20c, 20d, and 20e have the earliest scheduled arrival times at the intersection, the entry permission periods are set in the following order: entry permission period Tr based on ideal passing period Ir of vehicle group 20r, entry permission period Ts1 based on the first divided period Is1 of vehicle group 20s, entry permission period Tt1 based on the first divided period It1 of vehicle group 20t, entry permission period Ts2 based on the second divided period Is2 of vehicle group 20s, and entry permission period Tt2 based on the second divided period It2 of vehicle group 20t. Although not shown in Fig. 10, entry non-permission periods are set other than the entry permission periods.

[0043] [Function configuration] Fig. 11 is a diagram showing an example of a functional configuration of the signal control system 1. According to Fig. 11, the signal control system 1 includes, as functional units, an operation unit 102, a display unit 104, a sound output unit 106, a communication unit 108, a processing unit 200, and a storage unit 300, and is configured as a type of computer system.

[0044] The operation unit 102 is realized by an input device such as a button switch, a touch panel, or a keyboard, and outputs an operation signal corresponding to the operation performed to the processing unit 200. The display unit 104 is realized by a display device such as an LCD (Liquid Crystal Display) or a touch panel, and performs various displays corresponding to a display signal from the processing unit 200. The sound output unit 106 is realized by a speaker, and outputs sound based on a sound signal such as an alarm sound input from the processing unit 200. The communication unit 108 is realized by a wired or wireless communication device, and communicates with an external device such as a communication control device 12 mounted on the automobile 30 via a wireless base station 3 connected to the communication network N.

[0045] The processing unit 200 is realized by an arithmetic device such as a CPU (Central Processing Unit), and issues instructions and transfers data to each unit constituting the signal control system 1 based on programs, data, etc. stored in the storage unit 300, thereby controlling the entire signal control system 1. The processing unit 200 also has, as functional units according to this embodiment, a traveling information acquisition unit 202, a determination unit 204, a signal management unit 206, and a notification control unit 208. However, these functional units can also be configured as independent arithmetic circuits using an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), etc.

[0046] The travel information acquisition unit 202 acquires travel information from the automobile 10. Specifically, the travel information is acquired by receiving the travel information from the automobile 10 through communication via the communication unit 108. The travel information acquisition unit 202 updates the automobile management information 310 of the corresponding automobile 10 based on the acquired travel information 32. The automobile management information 310 is information about the automobile 10 traveling on the road network that is the object of control by the signal control system 1, and stores the travel position, travel speed, travel direction, etc. obtained from the travel information 32 for each automobile 10 in association with the automobile ID of the automobile 10.

[0047] The determination unit 204 determines, based on the travel information 32, vehicle groups 20 each consisting of one or more automobiles 10 that are scheduled to enter an intersection from the same entrance direction, by entrance direction, and determines the estimated arrival time at the intersection for the vehicle groups 20. In addition, based on the travel information 32, the determination unit 204 determines, for each vehicle group 20, an ideal passing period for the intersection starting from the estimated arrival time.

[0048] Specifically, by referring to the vehicle management information 310, a group of vehicles that have the same approach route to the intersection and are spaced apart by a predetermined distance or less is determined as a vehicle group 20. Then, for the determined vehicle group 20, for example, the distance from the leading position of the leading vehicle of the vehicle group 20 to a predetermined position at the intersection (for example, the position of the stop line) is calculated, and the required time to reach the intersection is calculated from this distance and the traveling speed of the vehicle group 20. The time after the required time has elapsed from the reference time corresponding to the calculated timing is set as the scheduled time to reach the intersection. The traveling speed of the vehicle group may be, for example, a speed included in the traveling information 32, or may be a speed that is determined in advance because the vehicle 10 is autonomous.

[0049] Also, the length of the vehicle group 20 is calculated by, for example, adding a predetermined margin distance to the distance from the leading position of the leading vehicle in the vehicle group 20 to the rearmost position of the rearmost vehicle, or by setting the distance to a predetermined distance according to the number of vehicles constituting the vehicle group 20. Then, the ideal passing period is set to a period of time according to the length of the vehicle group, starting from the scheduled arrival time of the vehicle group at the intersection.

[0050] The data on the vehicle group 20 determined by the determination unit 204 is stored as entering vehicle group data 321 in the intersection management information 320 related to the relevant intersection. Fig. 12 is a diagram showing an example of the entering vehicle group data 321. As shown in Fig. 12, the entering vehicle group data 321 stores vehicle group data for each vehicle group 20 in association with a reference time. The vehicle group data stores a vehicle group ID, a constituent vehicle list which is a list of the vehicles 10 (vehicle IDs) that constitute the vehicle group 20, an approach route to the intersection, a distance to the intersection, an expected time of arrival at the intersection, a vehicle group length, and an ideal passing period for the intersection in association with each other.

[0051] Based on the determination result of the determination unit 204, the signal management unit 206 sets a single permitted approach route and an approach permission period for each vehicle group 20 that permits entry into the intersection on a given time axis, and treats all approach routes as stop signals during periods other than the permitted approach period, thereby managing signals according to the passage of time. Also, the signal management unit 206 sets the approach permission period as the permitted approach route for the approach route into which the vehicle group 20 enters, so that the permitted approach periods for each vehicle group 20 do not overlap. Also, the signal management unit 206 sets the permitted approach period on the time axis by allocating the permitted approach period in order from the vehicle group 20 with the earliest estimated arrival time. Also, the signal management unit 206 sets the permitted approach period for each vehicle group 20 based on the ideal passing period. Also, when there are vehicle groups 20 with overlapping ideal passing periods, the signal management unit 206 divides the ideal passing period of one or both of the overlapping vehicle groups 20, and sets the permitted approach period corresponding to each divided ideal passing period. In this case, the divided ideal passing period or entry permission period is set to a predetermined minimum time length or longer (see Figs. 4 to 7).

[0052] Data related to signals managed by the signal management unit 206 is stored as entry permission setting data 322 in the intersection management information 320 related to the corresponding intersection. Fig. 13 is a diagram showing an example of the entry permission setting data 322. As shown in Fig. 13, the entry permission setting data 322 stores, in association with a reference time, whether entry to the intersection is permitted (permitted / not permitted), an entry-permitted route which is a route for which entry is permitted, and a vehicle group permitted to enter (vehicle group ID) for each consecutive period starting from the reference time.

[0053] The notification control unit 208 generates signal management information 34 based on the management contents by the signal management unit 206 and controls notification of the signal management information 34 to the automobile 10. In addition, the notification control unit 208 includes information on the entry permission period set for the vehicle group 20 in the signal management information 34 and notifies the vehicle 10.

[0054] Specifically, the notification control unit 208 periodically refers to the intersection management information 320 corresponding to each intersection to be controlled, and generates signal management information 34 including the permitted entry route and entry permission period set for each vehicle group 20 scheduled to enter the intersection. Then, the notification control unit 208 notifies the automobiles 10 constituting the vehicle group 20 by transmitting the signal management information 34 via the communication unit 108. The vehicle group 20 scheduled to enter the intersection can be determined from the scheduled entry vehicle group data 321, and the permitted entry route and entry permission period set for the vehicle group 20 can be determined from the entry permission setting data 322. The intersection management information 320 is generated for each intersection to be controlled by the signal control system 1, and stores route information related to the configuration of the route, the scheduled entry vehicle group data 321, and the entry permission setting data 322 in association with the intersection ID of the intersection.

[0055] The storage unit 300 is realized by a storage device such as a hard disk, a ROM (Read Only Memory), or a RAM (Random Access Memory), and stores programs, data, and the like for the processing unit 200 to comprehensively control the signal control system 1. The storage unit 300 is also used as a working area for the processing unit 200, and temporarily stores results of calculations executed by the processing unit 200 in accordance with various programs, input data via the operation unit 102 and the communication unit 108, and the like. In this embodiment, the storage unit 300 stores a signal control program 302, automobile management information 310, and intersection management information 320.

[0056] The signal control program 302, when executed by the processing unit 200, realizes a function of controlling signals at predetermined intersections in a road network on which autonomously driven automobiles travel.

[0057] [Processing flow] 14 is a flowchart illustrating the flow of signal control processing performed by the signal control system 1. The signal control system 1 performs this processing in parallel for each intersection that is the subject of control.

[0058] First, the determination unit 204 determines the vehicle groups 20 that are scheduled to enter the intersection (step S1). Next, it is determined whether entry permission has been set for each of the determined vehicle groups 20 that are scheduled to enter. If entry permission has been set for all of the vehicle groups 20 (step S3: NO), the process proceeds to step S19.

[0059] If there is an unset vehicle group 20 for which entry permission has not been set (step S3: YES), the determination unit 204 calculates the estimated time of arrival at the intersection and the ideal period for passing through the intersection for each of the unset vehicle groups 20 (step S5). Next, the signal management unit 206 selects the vehicle group 20 with the earliest estimated time of arrival at the intersection from among the vehicle groups 20 for which entry permission has not been set (step S7).

[0060] Next, it is determined whether the ideal passing period of the target vehicle group overlaps with the entry permission period of the other vehicle groups 20. If they do not overlap (step S9: NO), the ideal passing period of the target vehicle group is set as the entry permission period (step S11). On the other hand, if the ideal passing period of the target vehicle group overlaps with the entry permission period of the other vehicle groups 20 (step S9: YES), the divisible periods of the ideal passing period of the target vehicle group and the other vehicle groups 20 that overlap are divided (step S13). Then, for each of these vehicle groups 20, an entry permission period based on the ideal passing period or a period (divided) obtained by dividing the ideal passing period is set so that the vehicles travel in order of the earliest scheduled arrival time at the intersection (step S15). After that, it is determined whether the advance permission is set for all vehicle groups 20. If there is a vehicle group 20 for which the advance permission is not set (step S17: NO), the process returns to step S7.

[0061] If entry permission is set for all vehicle groups 20 (step S17: YES), the notification control unit 208 then generates signal management information 34 including the permitted entry route and entry permission period for each vehicle group 20 scheduled to enter the intersection, and notifies each automobile 10 constituting the vehicle group 20 (step S19). After that, the process returns to step S1 and the same process is repeated.

[0062] [Effects] According to this embodiment, a new method of signal control at an intersection where an autonomous vehicle 10 travels can be provided. In other words, the signal control system 1 performs a completely new signal control at an intersection that is completely different from the conventional one, by setting, on a given time axis, a unique permitted approach direction and an approach permission period that permits entry for each vehicle group 20 that is scheduled to enter the intersection from the same approach direction, and treating all approach directions as stop signals during periods other than the approach permission period. In addition, since the approach permission periods for each vehicle group 20 are set so as not to overlap, the signal control is such that each vehicle group 20 occupies the entrance to the intersection, so to speak.

[0063] In this way, the number of routes permitted to enter the intersection is at most one, and vehicles 10 are allowed to enter the intersection in groups of vehicles 20, which prevents vehicles 10 from crossing paths at the intersection in terms of driving direction, and reduces congestion, enabling smooth and efficient traffic flow. Signal management information 34 based on the management of signals at the intersection is notified to each vehicle 10, so that autonomous vehicles 10 can enter the intersection in accordance with the set permitted entry route and permitted entry period.

[0064] Incidentally, the applicable embodiments of the present invention are not limited to the above-described embodiments, and can of course be modified as appropriate without departing from the spirit of the present invention. [Explanation of symbols]

[0065] 1. Signal control system 200... Processing section 202…Driving information acquisition unit 204...Judgment section 206…Signal management department 208...Notification control unit 300...Storage section 302…Signal control program 310…Car management information 320…Intersection management information 3...Radio base station 10. Automobiles 12...Wireless device 14...Drive control device 20…Vehicle group 32...Driving information 34…Signal management information

Claims

1. A signal control system that controls signals at a predetermined intersection where an autonomous vehicle runs, the vehicle is equipped with a communication control device that communicates with the signal control system, and an entrance control device that controls entrance to the intersection based on given signal management information received from the signal control system; A driving information acquisition means for acquiring driving information from the vehicle; a determination means for determining, based on the travel information, a vehicle group consisting of one or more vehicles that are scheduled to enter the intersection from the same entrance road, by the entrance road, and determining an expected arrival time of the vehicle group at the intersection; a signal management means for managing signals according to the passage of time by setting, for each vehicle group, a unique permitted approach direction and an approach permission period for permitting entry into the intersection on a given time axis based on a determination result of the determination means, and treating all approach directions as stop signals during periods other than the permitted approach period; a notification control means for generating the signal management information based on the management contents by the signal management means and controlling the generation of the signal management information and notifying the vehicle of the information; A signal control system comprising:

2. the signal management means sets the entry permission period by setting an entry route through which the vehicle group enters as the permitted entry route so that the entry permission periods for the vehicle group do not overlap, The notification control means notifies the vehicle group by including information on the entry permission period set for the vehicle group in the signal management information. The signal control system according to claim 1 .

3. the signal management means sets the entry permission period on the time axis by allocating the entry permission period in order from the vehicle group having the earliest scheduled arrival time.

3. A signal control system according to claim 1 or 2.

4. The determination means determines, for each of the vehicle groups, an ideal passing period through the intersection starting from the estimated arrival time based on the travel information, the signal management means sets the entry permission period for each vehicle group based on the ideal passing period.

3. A signal control system according to claim 1 or 2.

5. the signal management means, when there are vehicle groups whose ideal passing periods overlap, divides the ideal passing periods of one or both of the overlapping vehicle groups, and sets the entry permission periods corresponding to the divided ideal passing periods, respectively. The signal control system according to claim 4.

6. the signal management means sets the ideal passing period or the entry permission period after division to be equal to or longer than a predetermined minimum time length; The signal control system according to claim 5.

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