Patent Application
20240144814
The present invention relates to a traffic signal control apparatus, a control method of the traffic signal machine and a program recording medium.
A traffic signal is known, which has a function that, when a vehicle traveling at a speed exceeding the legal speed limit is detected, by shortening a green signal time period or extending a red signal time period of a downstream traffic signal machine, stops the vehicle at a downstream intersection so as to prevent the vehicle from traveling at a speed exceeding a legal limit (high-speed sensitive control).
Patent Literature 1 (PTL 1) discloses a traffic signal control apparatus that may more reliably control the speed of an excess speed vehicle. The traffic signal control apparatus described in PTL 1 executes a first determination to determine whether or not it is possible to stop a target vehicle to be deterred from traveling at a downstream intersection thereof, and a second determination to determine whether or not it is possible to shorten green signal time period on a road where the target vehicle will enter at the intersection. If the first and second determinations at a certain intersection are negative, the traffic signal control apparatus executes the first and second determinations for a next intersection at downstream of the intersection in traveling direction of the target vehicle.
In addition, Patent Literature 2 and Patent Literature 3 are exemplified as related literatures.
The following analysis is provided by the present inventor. As described in PTL 1, there is a case where a traffic signal machine having a high-speed sensitive control function cannot stop the target vehicle. In this point, PTL 1 discloses a method in which the target vehicle may be stopped at a traffic signal machine located ahead. However, such determination is executed based on whether it is possible or not to stop the vehicle (the first determination) and whether it is possible or not to shorten green signal time period or whether it is possible or not to extend red signal time period (the second determination). Therefore, the method of PTL 1 has a possibility that shortening of green signal time period or extension of red signal time period is executed at an improper location or timing, resulting in deterioration of traffic congestion.
It is a purpose of the present invention to provide a traffic signal control apparatus, a control method of traffic signal machine and a program recording medium that may suppress occurrence of traffic congestion and the like by virtue of signal control for stopping a particular vehicle.
According to a first aspect, there is provided a traffic signal control apparatus, comprising means for determining whether or not to stop a vehicle based on behavior of the vehicle entering a predetermined intersection; and means for selecting a traffic signal machine or machines that perform signal control for stopping the vehicle from among control target traffic signal machines. The means for selecting the traffic signal machine of the traffic signal control apparatus selects a traffic signal machine or machines that is/are located in a traveling direction of the vehicle and traffic congestion has occurred at the intersection.
According to a second aspect, there is provided a control method of a traffic signal machine, comprising: determining whether or not to stop a vehicle based on behavior of the vehicle entering a predetermined intersection, and selecting a traffic signal machine(s) that is/are located in a traveling direction of the vehicle and that traffic jam has occurred at a site where the traffic signal machine is located from control target traffic signal machines as a traffic signal machine(s) that perform(s) the signal control for stopping the vehicle. The method is connected to a specific machine as a traffic signal control apparatus that controls the traffic signal machine(s).
According to a third aspect, there is provided a computer program (referred to as program, hereinafter) for realizing above functions of a computer. Herein, the computer program is input to a computer apparatus from an input apparatus or an external device via a communication interface, stored in a storage apparatus, and causes a processor to drive according to predetermined steps or processes. In addition, the program may display a processing result including intermediate states, step by step via a display device, if necessary, or may communicate with an external device via the communication interface. A computer device for this purpose is, as an example, typically comprises a processor, a storage device, an input device, a communication interface, and a display device, if necessary, that may be connected to one another via a bus. The program may also be recorded on a computer-readable (non-transitory) storage medium. That is, the present invention may also be realized as a computer program product.
According to the present invention, it is realized to suppress occurrence of traffic congestion and the like due to signal control for stopping a particular vehicle.
First, an outline of one example embodiment of the present invention is explained with reference to drawings. Herein, symbols appended to the outline are expediently appended to each element as one example for a purpose of easy understanding, thus are not intended to limit the present invention to an illustrated mode. In addition, connection lines between blocks in the drawings and the like, made reference in the following explanation, include both of bidirection and one directional. One way arrow schematically indicates flow of main signal (data), thus does not exclude bidirection. Further, input/output connection points of each block in the drawings have a port and an interface, although omitted in the drawings. A program is executed via a computer apparatus, and the computer apparatus comprises, for example, a processor, a storage device, an input device, a communication interface and a display device, as necessary. Further, the computer apparatus is configured in a manner capable of communicating with an internal equipment or an external equipment (including a computer) via the communication interface, irrespective of a cable communication or a radio communication.
As illustrated in
More concretely, the determination part 103a functions as means for determining whether or not to stop a vehicle based on behavior of the vehicle detected by a sensor 201a installed at a predetermined location.
The selection part 102a functions as means for selecting a traffic signal machine that performs signal control for stopping the vehicle from control target traffic signal machines 203-1, 203-2. Upon the selection of the traffic signal machine, the selection part 102a selects a traffic signal machine which is located in a traveling direction of the vehicle and may eliminate traffic jam in the cross direction by performing signal control for stopping the vehicle. Herein, whether or not performing signal control for stopping the vehicle may eliminate the traffic jam in the crossing direction may be determined by detecting vehicles and pedestrians waiting for a traffic signal with sensors 202-1 and 202-2 installed near (around) the control target traffic signal machines 203-1, 203-2. Herein, as the sensors 201a, 202-1, 202-2, various sensors using ultrasonic waves and optical beacon millimeter waves, as well as image-based sensors using cameras LiDAR (Light Detection and Ranging) may be used. Of course, it is not limited to install only one single sensor at one site, thus multiple sensors of one or more kinds may be installed in combination according to a detection target and parameters to be measured.
For example, as illustrated in
The selection part 102a selects a traffic signal machine that performs signal control for stopping the vehicle V1 from among the traffic signal machines 203-1, 203-2 located in the traveling direction of the vehicle V1. At that time, the selection part 102a selects the traffic signal machine 203-2 that has determined the presence of a vehicle V2 waiting for signal change by the sensor 202-2. In addition, the selection part 102a instructs the selected traffic signal machine 203-2 to perform the signal control for stopping the vehicle V1. As the signal control for stopping the vehicle, early termination of green signal time period, extension of red signal time period, and the like may be adopted.
When the instructed traffic signal machine 203-2 performs signal control for stopping the vehicle V1, the vehicle V2 waiting for signal change at the traffic signal machine 203-2 starts to travel according to (changed) signaling of the traffic signal machine 203-2. On the other hand, as illustrated in
As described above. according to the present exemplary embodiment, not only stopping the target vehicle V1, but it is realized to eliminate staying of the vehicle V2 in the cross direction. In addition, early termination of the green signal time period and the extension of red signal time period at the site where the vehicle V2 stays may provide more potent necessity of stopping or deceleration to a driver of the vehicle V1 due to signal control by the traffic signal machine 203-1 having no vehicles waiting for signal change.
Next, a first exemplary embodiment of the present invention is explained in detail with reference to the drawings, in which cameras are used for determination of vehicles to be targets for the stop control and detection of vehicles waiting for signal change.
The traffic signal control apparatus 100 comprises a signal control part 101, a control position selection part 102, a target vehicle determination part 103, a traffic signal machine position storing part 104 and a staying vehicle detection part 106. The traffic signal control apparatus 100 having such configuration may be a control apparatus installed in a traffic control center.
The signal control part 101 controls a traffic signal machine(s) 111 within a control target area. In addition, control content of the traffic signal machine(s) 111 by the signal control part 101 is also transmitted to the target vehicle determination part 103. Although only a single traffic signal machine is illustrated in
The target vehicle determination part 103 determines vehicle(s) to be target(s) for stop control based on control content of the traffic signal machine 111 by the signal control part 101 and image obtained from the camera 105-1. In the present exemplary embodiment, the following explanation is made under an assumption that a vehicle is determined, which has entered and passed through an intersection during signaling of yellow signal, and stop control over the vehicle is performed. Herein, determination of vehicle that has performed such particular behavior may be done using recognition technology such as that used in automated driving to recognize other vehicles, etc.
The control position selection part 102 selects position to stop a vehicle determined by the target vehicle determination part 103 based on position information of the traffic signal machine 111, which is stored in the traffic signal machine position storing part 104, and information obtained by the staying vehicle detection part 106.
The traffic signal machine position storing part 104 stores position information of the traffic signal machine 111 to be a control target by the traffic signal control apparatus 100.
The cameras 105-1, 105-2 are cameras installed in different intersections.
The staying vehicle detection part 106 measures the presence or absence of vehicle(s) or pedestrian(s) waiting for signal change based on image obtained from the camera 105-2.
The camera 105-2c at bottom left in
Next, operations by the present exemplary embodiment are explained in detail with reference to the drawings.
The traffic signal control apparatus 100 which has detected the vehicle to be the target of stop control determines a traveling direction of the vehicle (Step S002). Next, the traffic signal control apparatus 100 extracts traffic signal machines located in the traveling direction of the vehicle as candidates of the traffic signal machines 111 that are made to perform the stop control to the target vehicle (Step S003). For example, in a case where a vehicle traveling from the right side to the left side in
The traffic signal control apparatus 100 obtains surrounding image(s) of the traffic signal machines 111 installed at the intersections C22, C21, and detects the presence or absence of the vehicles and pedestrians waiting for signal change by the staying vehicle detection part 106 (Step S004). Herein, in a case where the vehicles and pedestrians waiting for signal change have been detected at a plurality of intersections, the traffic signal control apparatus 100 selects a traffic signal machine 111 of a larger number of the vehicles and pedestrians waiting for signal change from among the traffic signal machines 111 installed at the intersections C22, C21 (Step S005). For example, in a case of
The traffic signal control apparatus 100 instructs the traffic signal machine(s) 111 installed at the intersection C21 to perform signal control for stopping the target vehicle (Step S006). Accordingly, the traffic signal machine(s) 111 installed at the intersection C21 performs early switching over to green signal light and extension of red signal light. Thereby, traffic jam at the intersection C21 may be eliminated and it is realized to stop the target vehicle.
Although the above example is explained under an assumption that the presence or absence of vehicles and pedestrians waiting for signal change is detected and stop control to the target vehicle is performed by a traffic signal machine(s) at that site, “traffic” to be determination target that may eliminate traffic jam is not limited to the example. For example, as illustrated in
In addition, although the above example is explained under an assumption that a traffic signal machine(s) that performs signal control for stopping a target vehicle is selected from among the traffic signal machines 111 installed at intersections, there are traffic signal machines which are installed at a site where a crosswalk is provided, but not at intersections (see
In addition, although the above example is explained using with reference to an example under the assumption that a target vehicle goes straight through an intersection C22 and thus a traffic signal machine(s) installed at an intersection C21 is added to candidate, a possibility of turning left or right of the target vehicle at the intersection C22 may be also added to consideration. In such case, a control target traffic signal machine(s) may be selected by obtaining the travelling direction of the target vehicle at the intersection C22. As another method, in a case where a traffic classification by travelling directions of the intersection C22 at which a target vehicle is located and a tendency of statistical course of vehicles at the intersection C22 have been obtained, the traffic signal machines that performs signal control for stopping the target vehicle may be narrowed down using this information. For example, as illustrated in
In addition, in an example illustrated in
As described above, each of the exemplary embodiments of the present invention has been explained. However, the present invention is not limited to the above exemplary embodiments, thus further modifications, substitutions and adjustments may be added thereto within an ambit that they do not depart from the basic technical concept of the present invention. For example, apparatus configurations, configuration of each element, representation mode of data, etc., which are illustrated in each drawing, are an example to aid in understanding the present invention, thus not limited to those configurations illustrated in these drawings. For example, although the first exemplary embodiment is explained under an assumption that a vehicle failing to stop under yellow signal is defined as a target, the behavior of the vehicle to be defined as a control target is not limited thereto. For example, vehicles that exceed the speed limit, disregard other traffic signals, tailgating, change lanes recklessly, etc., may be defined as the target of stop control. In addition to other vehicle behaviors, of course, vehicles that are found to be in violation of vehicle maintenance or not wearing seat belts may also be defined as the target of stop control.
Although omitted from the description in the above exemplary embodiments, the vehicle and its owner may be identified using license plate recognition technology, facial recognition technology, etc., as necessary. Further, the information identified in such way may also be used to query a cloud side for the vehicle's route and destination, enabling more accurate prediction of the target vehicle's path.
Further, although omitted from the description in the above exemplary embodiments, upon selecting a traffic signal machine(s) that performs signal control for stopping the vehicle, it may be possible to determine whether it is possible to stop an intended vehicle by [early] switching over to green light signal or extending red light signal, like as in PTL 1.
Further, although in the exemplary embodiments, determination is performed whether a vehicle should be stopped or not based on behavior of the vehicle entering a predetermined intersection, a case would be prospected where the vehicle would disregard the traffic signal or travel at overspeed due to emergency evacuation action. In order to avoid stopping vehicles which have made such behavior, a configuration may be also adopted, in which past behavior of each vehicle is stored for a certain period of time and used for judgement. For example, the traffic signal control apparatus may store behavior of each vehicle at an intersection for a predetermined period, and determine whether or not to stop a vehicle based on the stored behavior. For example, the traffic signal control apparatus may determine to stop a vehicle which has made a predetermined or more times of disregard of traffic signals within a predetermined period of time. There are also two possible cases for the number of times of disregard of traffic signals: a case of counting the number of times of disregard of a traffic signal at a site where the same traffic signal machine is located; and a case of counting the number of times of disregard of a traffic signal within an area of a traffic signal control apparatus.
In addition, there is a case where a certain vehicle driver habitually makes dangerous driving. In such a case, there is a possibility that the vehicle would not stop and repeatedly disregard a traffic signal even if the signal control for stopping the vehicle is performed. In light of such aspect, the traffic signal control apparatus may have a function that, for example, the signal control for stopping the vehicle is stayed (terminated) if the speed of the target vehicle is a predetermined value or more.
In addition, emergency vehicles, etc., which possibly make a behavior to be defined as a control target in the course of their duties may be excluded from the target of the stop control. In such case, a traffic signal control apparatus 100 may be equipped with a function to remove such vehicles from a control target if the control target could be recognized as an emergency vehicle, etc. from mage captured by the camera.
In addition, although the exemplary embodiments have been explained under an assumption that the traffic signal control apparatus 100 directly controls the traffic signal machines, there are also cases where a relay apparatus for controlling traffic signal machines within an intersection is installed in the intersection and the like. In such case, the traffic signal control apparatus 100 is assumed to instruct a control apparatus that controls the traffic signal machines in the corresponding intersection to perform signal control for stopping a target vehicle.
Further, the operations described in the above example embodiments may be realized by a program that allows a computer (9000 in
That is, each part (processing mean and function) of the above described traffic signal control apparatus 100 can be realized by a computer program that causes a processor in these apparatuses to perform each of the above processes using its hardware.
At the last, preferable modes of the present invention are summarized.
[First Mode]
(See the traffic signal control apparatus according to the first aspect.)
[Second Mode]
The traffic signal control apparatus may adopt a configuration that when a vehicle waiting to turn right stays at an intersection where the traffic signal is installed, the traffic signal control apparatus selects the traffic signal machine at the intersection as the traffic signal machine that performs the signal control for stopping the vehicle.
[Third Mode]
The traffic signal control apparatus may adopt a configuration that, in case where there is a vehicle or pedestrian waiting for signal change at a location where the traffic signal is installed, the traffic signal control apparatus selects the traffic signal machine as the traffic signal machine that performs the signal control for stopping the vehicle.
[Fourth Mode]
The traffic signal control apparatus may adopt a configuration to select a traffic signal machine or machines located one or more ahead in the traveling direction of the vehicle as a candidate or candidates of the traffic signal machine that performs the signal control for stopping the vehicle.
[Fifth Mode]
The traffic signal control apparatus may adopt a configuration to select a vehicle that disregards a traffic signal or signals or exceeds a speed limit as a stop target.
[Sixth Mode]
The traffic signal control apparatus may adopt a configuration to select a vehicle entering an intersection during signaling of a yellow signal as a stop target.
[Seventh Mode]
The traffic signal control apparatus may adopt a configuration to determine whether or not to stop a vehicle based on past behavior of the vehicle detected by the sensor or sensors.
[Eighth Mode]
The traffic signal control apparatus may adopt a configuration to stay (terminate) the signal control for stopping the vehicle in a case where the vehicle has a speed of predetermined value or more.
[Ninth Mode]
(See the traffic signal machine control method according to the second aspect.)
[Tenth Mode]
(See the computer program according to the third aspect.)
Herein, the ninth to tenth modes may be developed to second to eighth modes, likewise as the first mode.
Herein, it is considered that each disclosure of the above Patent Literatures is incorporated herein by reference thereto, and the disclosures may be used as a base or a part of the present invention as necessary. Variations and adjustments of the example embodiments and examples are possible within the ambit of the entire disclosure (including the claims) of the present disclosure and based on the basic technical concept thereof. In addition, various combinations and selections (including non-selection) of various disclosed elements (including each element in each claim, each example embodiment, each drawing, etc.) are possible within the ambit of claims of the disclosure. Namely, the present disclosure of course includes various variations and modifications that could be made by those skilled in the art according to the overall disclosure including the claims and the technical concept. In particular, the numerical range described in the present application should be interpreted as specifically describing any numerical value or subrange that falls within that range, even if not explicitly stated. Further, each of the disclosed matters of the above cited literatures is regarded as included in the described matters in the present application, if required, on the basis of the concept of the present disclosure, as a part of the present disclosure, also that a part or entire thereof is used in combination with a described matter(s) in the present application.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/009624 | 3/10/2021 | WO |
