Traffic signal control device, sensing control method, and computer program

Abstract

To provide a traffic signal controller capable of improving safety for pedestrians, etc., crossing an intersection where traffic lights are installed.SOLUTION: The present invention relates to a traffic signal controller comprising a control unit for acquiring an arrival time of a vehicle, which travels an approach path to an intersection, at the intersection and executing traffic actuated control to change indication times of signal lamps based on the acquired arrival time. The signal lamps include a lamp for vehicles which indicates the presence / absence of a right of passage to the vehicle traveling the approach path. The traffic actuated control includes first traffic actuated control in which, in a case where the arrival time is included in a total red time of the lamp for vehicles, the total red time is extended just for a predetermined time.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a traffic signal controller, a sensing control method, and a computer program.

Background Art

[0002] Patent Document 1 describes a signal control method for preventing a rear-end collision accident at an intersection that occurs when there is a vehicle attempting to pass through the intersection beyond the stop line from the approach side of the intersection within a predetermined time after the traffic signal has switched to a red signal. Patent Document 2 describes a driving support device that can prevent a driver's momentary sense of fear and delay in braking operation even when there are vehicles turning right at an intersection or the like during the determination of passing through or stopping at an intersection.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the technologies described in Patent Documents 1 and 2 are both technologies related to alerting or assisting the driver of a vehicle, they are effective only when the driver himself / herself is in a normal state. Therefore, in Patent Documents 1 and 2, for example, in the case where a vehicle (hereinafter referred to as a "dangerous vehicle") occupied by a driver in a non-normal state, such as a driver under the influence of alcohol, drowsy, distracted, using drugs, or having a speeding addiction, occurs, no measures are assumed to ensure the safety of pedestrians.

[0005] In view of such conventional problems, an object of the present disclosure is to provide a traffic signal controller or the like that can improve the safety for pedestrians and the like crossing an intersection where a traffic signal is installed.

Means for Solving the Problems

[0006] An apparatus according to an aspect of the present disclosure is a traffic signal controller including a control unit that acquires an arrival time of a vehicle passing through an inflow road to an intersection at the intersection and executes a sensitive control for changing a display time of a signal lamp based on the acquired arrival time, wherein the signal lamp includes a vehicle lamp that indicates whether the vehicle passing through the inflow road has the right of way, and the sensitive control includes a first sensitive control for extending the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp.

[0007] A method according to an aspect of the present disclosure is a sensitive control method executed by a traffic signal controller, including steps of acquiring an arrival time of a vehicle passing through an inflow road to an intersection at the intersection and executing a sensitive control for changing a display time of a signal lamp based on the acquired arrival time, wherein the signal lamp includes a vehicle lamp that indicates whether the vehicle passing through the inflow road has the right of way, and the sensitive control includes a first sensitive control for extending the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp.

[0008] A computer program according to an aspect of the present disclosure is a computer program that causes a computer to function as a traffic signal controller including a control unit that acquires an arrival time of a vehicle passing through an inflow road to an intersection at the intersection and executes a sensitive control for changing a display time of a signal lamp based on the acquired arrival time, wherein the signal lamp includes a vehicle lamp that indicates whether the vehicle passing through the inflow road has the right of way, and the sensitive control includes a first sensitive control for extending the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp.

[0009] The present disclosure can be realized not only as a system and apparatus having the characteristic configuration as described above, but also as a program for causing a computer to execute such a characteristic configuration. Further, the present disclosure can be realized as a semiconductor integrated circuit that realizes part or all of the system and apparatus.

Advantages of the Invention

[0010] According to the present disclosure, it is possible to improve the safety for pedestrians and the like crossing an intersection where a traffic signal is installed.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0012] <Outline of Embodiment of the Present Invention> Hereinafter, the outline of the embodiment of the present invention will be listed and described. (1) The traffic signal controller of this embodiment is a traffic signal controller including a control unit that acquires the arrival time of vehicles passing through the inflow roads to the intersection at the intersection, and performs a sensitive control to change the display time of the signal lamp based on the acquired arrival time. The signal lamp includes a vehicle lamp that displays the presence or absence of the right of way for the vehicles passing through the inflow road, and the sensitive control includes a first sensitive control that extends the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp.

[0013] According to the traffic signal controller of this embodiment, since the control unit executes the first sensitive control to extend the all-red time by a predetermined time when the arrival time of the vehicle at the intersection is included in the all-red time of the vehicle lamp, it is possible to suppress the pedestrians from crossing or the vehicles from entering the intersection from the intersecting road due to the delay in the start of the pedestrian green. Therefore, when the vehicle that enters the intersection during the all-red time is, for example, a dangerous vehicle, the safety for the pedestrians trying to cross or the vehicles trying to start from the intersecting road can be improved.

[0014] In the traffic signal controller of this embodiment, when executing the first sensitive control, the control unit may output a control command for operating a device that prompts the pedestrians to attract their attention in order to prevent so-called jaywalking. At the same time, a device that prompts the vehicles to attract their attention may also be activated.

[0015] (2) In the traffic signal controller of this embodiment, the signal lamp includes a pedestrian lamp that displays the right of way for the pedestrians crossing the inflow road, and the sensitive control may include a second sensitive control that cuts off the green time and starts the pedestrian green flashing when the arrival time is included in the green time of the pedestrian lamp. Here, for the increased green flashing time, the green flashing may be performed at different time intervals or methods from the normal green flashing.

[0016] According to the traffic signal controller of the present embodiment, when the arrival time of a vehicle at an intersection is included in the green time of the pedestrian signal lamp, the control unit executes a second responsive control to cut off the green time and start the pedestrian green flashing, so that the display of the pedestrian green flashing can be advanced to suppress the crossing of pedestrians. Therefore, when a vehicle that has entered the intersection during the green time of the pedestrian signal lamp is, for example, a dangerous vehicle, the safety for pedestrians can be improved.

[0017] (3) In the traffic signal controller of the present embodiment, when executing the first responsive control or the second responsive control, the control unit may output a control command for operating a device that prompts at least one of the pedestrians and the vehicles to pay attention.

[0018] In this way, the occurrence of a vehicle entering the intersection during the all-red time of the vehicle signal lamp or the occurrence of a vehicle entering the intersection during the green time of the pedestrian signal lamp can be brought to the attention of the vehicles and pedestrians waiting for the signal. Therefore, compared with the case where only the first responsive control or the second responsive control is executed, the safety for vehicles and pedestrians can be further improved.

[0019] (4) In the traffic signal controller of the present embodiment, at least one of dilemma responsive control, bus responsive control, gap responsive control, recall control, high-speed responsive control, and FAST responsive control may be processed in parallel with at least one of the first responsive control and the second responsive control.

[0020] In this way, for the intersection where the above terminal responsive control is executed, at least one of the first responsive control and the second responsive control can also be executed.

[0021] (5) In the traffic signal controller of the present embodiment, when executing the first responsive control or the second responsive control, the control unit may transmit the executed control content to the central device of the traffic control center.

[0022] In this way, since the control results of the first and second sensitivity controls become the management targets of the central device, the control results can be used for cause analysis in the event of a traffic accident.

[0023] (6) The sensitivity control method of the present embodiment is the sensitivity control method executed by the traffic signal controllers (1) to (5) described above. Therefore, the sensitivity control method of the present embodiment has the same operational effects as the traffic signal controllers (1) to (5) described above.

[0024] (7) The computer program of the present embodiment is a computer program for causing a computer to function as the traffic signal controllers (1) to (5) described above. Therefore, the computer program of the present embodiment has the same operational effects as the traffic signal controllers (1) to (5) described above.

[0025] <Details of Embodiments of the Present Invention> Hereinafter, details of embodiments of the present invention will be described with reference to the drawings. Note that at least a part of the embodiments described below may be arbitrarily combined.

[0026] [Overall Configuration of the System] FIG. 1 is a perspective view showing a configuration example of a signal control system 100 according to the present embodiment. As shown in FIG. 1, the signal control system 100 includes a plurality of signal lights 1 and 2 installed at an intersection J, a traffic signal controller 3, and a roadside sensor 4. In the present embodiment, one of the directions intersecting at the intersection J is referred to as the "main direction", and the other is referred to as the "subordinate direction". Also, the road in the main direction is referred to as the "main road", the road in the subordinate direction is referred to as the "subordinate road", and the road in the direction toward the intersection J is referred to as the "inflow road".

[0027] In FIG. 1, for example, the road extending in the east-west direction is the main road R1, and the road extending in the north-south direction is the subordinate road R2. The main road R1 includes an inflow road L1 that travels eastward toward the intersection J and an inflow road L2 that travels westward toward the intersection J. The secondary road R1 includes an inflow road L3 that travels southward toward the intersection J and an inflow road L4 that travels northward toward the intersection J.

[0028] The vehicle signal device 1 is a vehicle lamp device that indicates the presence or absence of the right of way for vehicles passing through the inflow roads L1 to L4. The vehicle lamp device 1 is installed on the outflow side of the intersection J. The vehicle lamp device 1 has at least red, blue, and yellow round lamps, and may include arrow signal lamps such as a right-turn arrow lamp. The pedestrian signal device 2 is a pedestrian lamp device that indicates the presence or absence of the right of way for pedestrians passing through the crosswalk. The pedestrian lamp device 2 is installed near the entrance and exit of the crosswalk. Hereinafter, when the vehicle lamp device 1 and the pedestrian lamp device 2 are collectively referred to, they are described as "signal devices 1, 2".

[0029] The traffic signal controller 3 is a device that controls the operation of the signal devices 1, 2, that is, a power control device that controls the lighting and extinguishing of a plurality of signal lamps included in the signal devices 1, 2. The traffic signal controller 3 is installed near the intersection J. The traffic signal controller 3 may be either a "standalone type" that is not connected to a dedicated line (such as a telephone line) leading to a central device (not shown) of the traffic control center or a "centralized type" that is connected to the dedicated line.

[0030] The roadside sensor 4 is a sensor that detects an object passing through a predetermined monitoring area A1 located in front of the intersection J on the inflow roads L1 and L2. The roadside sensor 4 is installed at an appropriate position beside the road so that the monitoring area A1 is within the detectable range of the sensor at a depression angle. The roadside sensor 4 may be any sensor that can detect the type (such as a vehicle or a pedestrian) and position of an object. For example, a digital camera capable of video shooting and a device including a radar sensor using a millimeter-wave method or a LiDAR method may be adopted.

[0031] The monitoring area A1 is set in a section where the downstream point and the upstream point are, for example, the following points. Downstream location: A point 10 m upstream from the stop lines of inflow roads L1 and L2 Upstream location: A point 50 m upstream from the stop lines of inflow roads L1 and L2 When detecting the presence or absence of pedestrians crossing the crosswalk, the monitoring area A2 including the crosswalk on the main road R1 may be included in the monitoring area of the roadside sensor 4.

[0032] The signal control system 100 of the present embodiment detects the positions and speeds of vehicles passing through the inflow roads L1 and L2 to the intersection J with the roadside sensor 4, and according to the arrival time of the vehicles at the intersection J estimated from the detection results, the traffic signal controller 3 performs sensitive control such as extending the all-red time of the inflow roads L1 and L2 or cutting off the green time in the transverse direction of the inflow roads L1 and L2. In the following, sensitive control with the inflow roads L1 and L2 as the control targets will be described, but similar sensitive control may be applied to the inflow roads L3 and L4.

[0033] 〔Internal configuration of traffic signal controller〕 FIG. 2 is a block diagram showing an example of the internal configuration of the traffic signal controller 3. As shown in FIG. 2, the traffic signal controller 3 includes a control unit 31, a storage unit 32, a communication unit 33, and a lamp driver unit 34. The control unit 31 is connected to the storage unit 32, the communication unit 33, and the lamp driver unit 34 via an internal bus. The control unit 31 controls the operations of these hardware components.

[0034] The control unit 31 is an arithmetic processing device including a CPU (Central Processing Unit) and a main memory. The control unit 31 reads the computer program 35 stored in the storage unit 32 into the main memory and performs various information processes according to the read program 35. The storage unit 32 is composed of a hard disk or other non-volatile memory and stores various computer programs 35 and data such as signal control parameters.

[0035] The communication unit 33 includes a communication module that executes communication with the roadside sensor 4. The communication method with the roadside sensor 4 may be either wireless or wired. In the case of the centralized traffic signal controller 3, the communication unit 33 also includes a communication module having a communication function with the central device.

[0036] The computer program 35 stored in the storage unit 32 includes a program for determining the lighting and extinguishing timings of the signal lights 1 and 2. For example, based on predetermined signal control parameters, the control unit 31 determines the on / off switching timing (hereinafter referred to as "light color switching timing") for each signal light in one cycle. When the local time of the own device reaches the determined light color switching timing, the control unit 31 outputs a switching signal to the lamp driving unit 34.

[0037] The lamp driving unit 34 includes a semiconductor relay (not shown). The semiconductor relay of the lamp driving unit 34 turns on or off the power supply to each signal light of the signal lights 1 and 2 according to the switching signal input from the control unit 31. In the case of the centralized traffic signal controller 3, the control unit 31 generates signal control execution information every time a cycle ends, and temporarily records the generated signal control execution information in the storage unit 32.

[0038] When a cycle ends, the control unit 31 inputs the signal control execution information for the most recent cycle to the communication unit 33. Alternatively, the control unit 31 may input the signal control execution information for a plurality of past cycles (for example, three cycles) including the most recent cycle to the communication unit 33. The communication unit 33 generates a communication frame including the input signal control execution information, and transmits the generated communication frame to the central device.

[0039] 〔Internal Configuration of Roadside Sensor〕 FIG. 3 is a block diagram showing an example of the internal configuration of the roadside sensor 4. As shown in FIG. 3, the roadside sensor 4 includes a control unit 41, a storage unit 42, a communication unit 43, a roadside camera 44, and a radar sensor 45. The control unit 41 is connected to the storage unit 42, the communication unit 43, the roadside camera 44, and the radar sensor 45 via an internal bus. The control unit 41 controls the operations of these respective hardware components.

[0040] The control unit 41 is an arithmetic processing unit including a CPU and a main memory. The control unit 41 reads the computer program 46 stored in the storage unit 42 into the main memory and performs various information processes according to the read program 46. The storage unit 42 is composed of a hard disk or other non-volatile memory and stores various computer programs 46 and data such as parameters for image processing.

[0041] The communication unit 43 includes a communication module that executes communication with the traffic signal controller 3. The communication method with the traffic signal controller 3 may be either wireless or wired. When the roadside sensor 4 directly communicates with the central device of the traffic control center, the communication unit 43 also includes a communication module having a communication function with the central device.

[0042] The roadside camera 44 is an image sensor that captures images of a predetermined shooting area. The roadside camera 44 may be either a monocular or a multiocular camera. The radar sensor 45 is a sensor that detects objects by means of millimeter-wave radar, LiDAR method, or the like.

[0043] The computer program 46 stored in the storage unit 42 includes programs for causing the control unit 41 to execute the following respective processes. 1) Object recognition: A process of recognizing the type of an object within the monitoring area A1 based on the measurement data of at least one of the roadside camera 44 and the radar sensor 45 2) Position measurement: A process of measuring the position information of the recognized object 3) Speed measurement: A process of measuring the speed of the recognized object

[0044] Object recognition is performed by comparing, for example, a polygon connecting predetermined feature points extracted from image data with a predetermined object shape (e.g., the shape of a vehicle) stored in advance. Position measurement is a process of calculating the position of an object from, for example, the distance and azimuth to the object obtained by a millimeter-wave radar using the FMCW (Frequency Modulated Continuous Wave) method and its own position information. Speed measurement is performed using, for example, the reflected chirp of a millimeter-wave radar of the FMCW (Frequency Modulated Continuous Wave) method.

[0045] The computer program 46 stored in the storage unit 42 also includes a program for causing the control unit 41 to execute the following respective processes. 4) Target detection: A process of detecting a target vehicle existing in the monitoring area A1 5) Calculation of arrival timing: A process of calculating the time when the target vehicle arrives at a predetermined position (e.g., the stop lines of the inflow roads L1 and L2) of the intersection J (hereinafter referred to as the "arrival time"), or the time length from the current time until the target vehicle arrives at the predetermined position of the intersection J (hereinafter referred to as the "arrival time").

[0046] (Specific example of target detection) Here, the "target vehicle" refers to a vehicle among the vehicles passing through the inflow roads L1 and L2 that is estimated to enter the intersection JL without stopping at a predetermined point such as a stop line. When the control unit 41 sets the actual distance as "RD" and the safe stop distance as "SD", the control unit 41 determines a vehicle for which RD < SD holds as the target vehicle. Therefore, the control unit 41 does not determine a vehicle for which RD ≧ SD holds as the target vehicle.

[0047] RD is the actual distance from the current position of the vehicle to a predetermined point that can be regarded as entering the intersection, and is calculated from the position information of the predetermined point and the position information of the vehicle. Here, the predetermined point is set as the stop line position of the inflow roads L1 and L2, but a position slightly shifted forward or backward from the stop line may also be used. SD is the distance at which the vehicle can stop safely and is calculated by the following formula. SD = τ × V + V 2 / (2 × De) However, τ is the reaction time of the driver, and De is the deceleration of the vehicle, both of which are preset in the roadside sensor 4.

[0048] (Specific example of arrival timing calculation) Assuming the arrival time of the target vehicle is "ta", the control unit 41 calculates ta according to the following formula. ta = tc + (RD / V) - Td However, tc is the current time, V is the speed of the vehicle at the current time, and Td is the delay time considering delays such as communication and information processing.

[0049] Assuming the arrival time of the target vehicle is "Ta", the control unit 41 calculates Ta according to the following formula. Ta = (RD / V) - Td However, V is the speed of the vehicle at the current time, and Td is the delay time considering delays such as communication and information processing.

[0050] The control unit 41 of the roadside sensor 4 generates a communication frame including the generation information of the target vehicle, and stores the data value of the arrival timing (ta or Ta) in the generated communication frame. Thereby, it is notified to the traffic signal controller 3 that the target vehicle has occurred and the arrival timing of the target vehicle at the intersection J.

[0051] [Ladder diagram of intersection display] FIG. 4 is a ladder diagram showing an example of signal display applicable to the intersection J. In FIG. 4, "-" means blue, "=" means red, "Y" means vehicle yellow, and "F" means pedestrian blue blinking. The ladder diagram of FIG. 4 is defined such that the signal display 1φ giving the right of way to the traffic (vehicles and pedestrians) on the main road R1 and the signal display 2φ giving the right of way to the traffic (vehicles and pedestrians) on the secondary road R2 are alternately displayed.

[0052] Specifically, the display 1φ of the main road R1 consists of five steps: main-direction pedestrian green (step 1), main-direction pedestrian green flashing (step 2), main-direction pedestrian red (step 3), main-direction vehicle yellow (step 4), and all-red (step 5). The display 2φ of the secondary road R2 consists of five steps: secondary-direction vehicle green (step 6), secondary-direction pedestrian green flashing (step 7), secondary-direction pedestrian red (step 8), secondary-direction vehicle yellow (step 9), and all-red (step 10).

[0053] 〔Sensing control by traffic signal controller〕 Figure 5 is a flowchart showing an example of the sensing control executed by the control unit 31 of the traffic signal controller 3. As shown in Figure 5, the control unit 31 monitors whether it has received the generation information of the target vehicle (step ST11). If it has received the generation information, it determines which step of the display ladder diagram (for example, Figure 4) the arrival time of the target vehicle is included in (step ST12).

[0054] In this case, when the arrival timing included in the received generation information is "ta" (the arrival time of the target vehicle), the control unit 31 executes the determination in step ST12 using the notified time value of ta. Also, when the arrival timing included in the received generation information is "Ta" (the arrival time of the target vehicle), the control unit 31 calculates the arrival time by adding Ta to the current time tc measured locally by itself, and executes the determination in step ST12 using the calculated time value.

[0055] When the determination result in step ST12 is "step 5" (main-direction all-red), the control unit 31 executes "first sensing control" to extend the all-red time of step 5 by a predetermined time. When the predetermined time is a set value, for example, it is from 1 to several seconds, and it is considered that an extension of the number of seconds of the originally intended red time of about up to 5 seconds is sufficient. The predetermined time may be dynamically changed according to the speed of the target vehicle, such as a calculated value obtained by dividing the distance from the stop line of the inflow path L1 to the crosswalk on the outflow side by the speed of the vehicle. In this case, the predetermined time is preferably changed in units of 0.1 second or even shorter time.

[0056] When the control unit 31 executes the first sensing control, it outputs a control command for operating a device that prompts a warning to prevent pedestrians from dashing across or vehicles from starting without waiting. As the device in this case, for example, the following devices can be considered. 1) A directional speaker that emits a sound such as danger 2) A rotating light (so-called patrol light ( "Patrol Light" is a registered trademark.)) 3) A light that flashes and blinks, attached to a pedestrian light or the like 4) An electromagnetic notification to a smartphone or the like 5) Electromagnetic communication to a vehicle by road-vehicle communication

[0057] When the determination result of step ST12 is "step 6" (pedestrian green in the following direction), the control unit 31 executes "second sensing control" to cancel the pedestrian green in the following direction in step 6 and switch to the flashing pedestrian green in the following direction in the next step 7. For example, in the ladder diagram of FIG. 4, when the arrival time of the target vehicle coincides with the time when 4 seconds have elapsed from the start of step 4, the remaining seconds 13 seconds (= 17 - 4) of step 4 are distributed to step 7. As a result, step 7 (flashing pedestrian green in the following direction) increases from 5 seconds to 18 seconds.

[0058] When the control unit 31 executes the second sensing control, it outputs a control command for operating a device that prompts a warning. As the device in this case, for example, the following devices can be considered. 1) A directional speaker that emits a sound such as danger 2) A rotating light (so-called patrol light) 3) A light that flashes and blinks, attached to a pedestrian light or the like 4) Electromagnetic notification to smartphones and the like 5) Electromagnetic communication with vehicles via road-vehicle communication

[0059] FIG. 6 is a time chart showing changes in signal display before and after execution of the first sensing control. As shown in FIG. 6, when the arrival time ta of the target vehicle is included in the all-red time in the main direction, the control unit 31 extends the all-red time in the main direction by a predetermined time ΔT. As a result, the start of the pedestrian green and vehicle green in the sub-direction is delayed by the predetermined time ΔT.

[0060] FIG. 7 is a time chart showing changes in signal display before and after execution of the second sensing control. As shown in FIG. 7, when the arrival time ta of the target vehicle is included in the pedestrian green time in the sub-direction, the control unit 31 cuts off the pedestrian green in the sub-direction and switches to pedestrian green blinking. In this case, the total time of the pedestrian green and pedestrian green blinking in the sub-direction is fixed, and the pedestrian green blinking time increases by the amount by which the pedestrian green time decreases.

[0061] 〔Types of terminal sensing control, etc.〕 “Terminal sensing control” refers to control that expands and contracts the green time, etc., in response to traffic fluctuations for each cycle based on sensing signals obtained from various sensors (such as non-image type or image type vehicle sensors) connected to the traffic signal controller 3. Examples of the types of terminal sensing control include dilemma zone sensing control, gap sensing control, bus sensing control, recall control, high-speed sensing control, and FAST sensing control.

[0062] In addition to the first sensing control and the second sensing control, the control unit 31 of the traffic signal controller 3 is capable of executing at least one of the above-described terminal sensing controls. Further, when performing the above-described terminal sensing control, the control unit 31 can also execute parallel processing with the first sensing control and the second sensing control. Hereinafter, specific examples of parallel processing with terminal sensing control will be described.

[0063] 〔Parallel processing with dilemma zone sensing control〕 "Dilemma sensing control" is a control aimed at reducing the risk of accidents by avoiding the area (dilemma zone) where the driver is confused about whether to stop or pass when a yellow signal is displayed for a vehicle about to enter an intersection. It is applied at intersections with many rear-end collisions and head-on collisions. As a control method, for example, when the vehicle is in the dilemma zone, the current green signal is continued, and when it is not, the green signal is cut off.

[0064] In the ladder diagram of Fig. 4, when performing dilemma sensing control in step 1, the remaining seconds from the next step (step 2) to step 4, which is one step before the all-red step 5 (hereinafter referred to as "RT"), is 12 seconds. The above RT value (= 12 seconds) is usually much larger than the time when the vehicle can safely stop (hereinafter referred to as "ST"). Therefore, there is no conflict with the dilemma sensing control.

[0065] In the ladder diagram of Fig. 4, when performing dilemma sensing control in step 3, RT is only 3 seconds in step 4. The above RT value (= 3 seconds) may be smaller than ST. Therefore, the execution of the first sensing control may be determined according to the comparison result between the arrival time Ta of the target vehicle and RT. In this case, when Ta > RT, that is, when the extension limit by the dilemma sensing control is exceeded, the first sensing control may be executed.

[0066] [Parallel processing with bus sensing control] "Bus sensing control" refers to a control that provides a bus sensor (for example, an optical beacon, a non-image vehicle sensor that performs narrow-area optical communication with the bus) in front of the intersection to identify the bus from the passing vehicles, and according to the detection of the bus, extends the green signal or shortens the red time to reduce the signal waiting time of the bus.

[0067] The extension of the green time in the bus sensing control usually extends step 1 of the pedestrian green, so it does not conflict with the first sensing control. Therefore, in the case of extending the green time, the first sensing control may be executed in parallel. When the bus's traveling direction has a red signal and the red time is shortened due to the approach of the bus, that is, when shortening the pedestrian green time in the following direction (step 6 in Figure 4), for example, the processing may be as follows.

[0068] That is, when second sensing control is required before executing the red time shortening due to bus sensing, the pedestrian green time may be cut off within the total range of the pedestrian green time and the pedestrian flashing time, and the extra time may be allocated to the pedestrian flashing time. In this case, the red shortening does not operate. When second sensing control is required after executing the red time shortening due to bus sensing, the pedestrian green time may be cut off within the total range of the pedestrian green time and the pedestrian flashing time after the red time shortening, and the extra time may be allocated to the pedestrian flashing time.

[0069] 〔Parallel processing with gap sensing control〕 "Gap sensing control" refers to control that extends the green time up to the extension limit number of seconds or shortens the green time by the shortening limit number of seconds when there is a following vehicle within a predetermined unit time (hereinafter referred to as "unit green") after the vehicle is sensed. In gap sensing control, since the next step is shifted at the time when the counting of the unit green is completed, when the remaining seconds (RT) from the next step after the gap sensing ends to one step before the red step to be extended is less than the safe stop seconds of the vehicle, the red time is extended.

[0070] In the ladder diagram of Figure 4, when gap sensing control is performed in step 1, the RT values from step 2 to step 4 are 12 seconds. The above RT value (= 12 seconds) is usually much larger than ST. Therefore, no conflict with gap sensing control occurs.

[0071] In the ladder diagram of Figure 4, when gap sensing control is performed in step 3, RT is only 3 seconds in step 4. The above RT value (= 3 seconds) may be smaller than ST. Therefore, according to the comparison result between the arrival time Ta of the target vehicle and RT, it is only necessary to determine whether the first sensitivity control can be executed. In this case, when Ta > RT, that is, when the extension limit by the gap sensitivity control is exceeded, the first sensitivity control may be executed.

[0072] [Parallel processing with recall control] "Recall control" refers to the sensitivity control that displays a green signal on the required side and gives the time necessary for crossing or passing by detecting a crossing request by pressing a pedestrian push button switch or detecting a vehicle by a vehicle sensor. Normally, it displays red, but since it calls back green when there is a request, it is called "recall".

[0073] As described above, the recall control determines whether to provide the green time on the secondary road side in response to a request from a pedestrian or the like. Therefore, when providing the green time on the secondary road side, it is only necessary to allow the first sensitivity control and the second sensitivity control. Note that when not providing the green time on the secondary road side, it is not necessary to execute the first sensitivity control and the second sensitivity control.

[0074] [Parallel processing with high-speed sensitivity control] "High-speed sensitivity control" refers to the sensitivity control that suppresses the speed of a vehicle traveling at high speed at night or the like by shortening the green time or extending the red time in the traffic signal controller 3 of the intersection J.

[0075] In general, the shortening of the green time in the high-speed sensitivity control is operated in step 1 of the pedestrian green. In this case, the start of the all-red time (step 5) is advanced. Therefore, when shortening the green time by the high-speed sensitivity control, it is preferable not to execute the first sensitivity control. However, since the installation position of the speed sensor that activates the high-speed sensitivity is installed several hundred meters upstream from the stop line of the controlled intersection, it is possible to execute the first sensitivity control with the sensor for the first sensitivity control after shortening the green time.

[0076] Since the extension of the red time stops the high-speed vehicle at the red signal, if the red time is extended before the arrival of "Step 5" (all red in the main direction) and it is determined that a safe stop at the stop line is impossible, the first-sensing control may be executed. At the same time, before the extension of the red time, when the second-sensing control is implemented, the reduction in the red time that should originally be extended, "Step 6" (green for crosswalk in the secondary direction), is switched to the next "Step 7" (flashing green for crosswalk in the secondary direction), and the "second-sensing control" that gives the number of seconds for which the red extension should be made to "Step 7" is executed. When the second-sensing control is implemented after the extension of the red time, it is also possible to perform the second-sensing control in response to the result increased in "Step 6".

[0077] [Parallel processing with FAST sensing control] "FAST sensing control" refers to control that extends the green time for pedestrians in the direction of travel of the emergency vehicle or shortens the green time for pedestrians in the direction intersecting the direction of travel of the emergency vehicle in order to facilitate the passage of the emergency vehicle through the intersection. Therefore, in the ladder diagram of Figure 4, Steps 1 and 6 are variable targets.

[0078] The extension of the green time in FAST sensing control usually extends Step 1 of the pedestrian green, so it does not conflict with the first-sensing control. Therefore, in the case of green time extension, the first-sensing control may be executed in parallel. In FAST sensing control, when extending Step 3 which is red for pedestrians and green for vehicles, the feasibility of executing the first-sensing control may be determined from before the start of the step in the same manner as in the case of dilemma sensing control.

[0079] When the direction of travel of the emergency vehicle is a red signal and the reduction of the red time due to the approach of the vehicle is executed, that is, when shortening the green time for pedestrians in the secondary direction (Step 6 in Figure 4), for example, the following processing may be performed.

[0080] That is, if the first-sensing control is required before executing the reduction of the red time due to the detection of the emergency vehicle, the green time for pedestrians may be terminated within the total range of the green time for pedestrians and the flashing time for pedestrians, and the extra time may be allocated to the flashing time for pedestrians. In this case, the red reduction does not operate. After executing the red time reduction based on the emergency vehicle detection, if the first detection control becomes necessary, the pedestrian green time may be terminated within the total range of the pedestrian green time and the pedestrian flashing time after the red time reduction, and the extra time may be allocated to the pedestrian flashing time.

[0081] 〔First Modification Example〕 In the above-described embodiment, the control unit 41 of the roadside sensor 4 may execute object recognition, position measurement, and speed measurement, and notify the traffic signal controller 3 of the position and speed of the vehicle. In this case, the control unit 31 of the traffic signal controller 3 may execute target detection and arrival timing calculation based on the position and speed of the vehicle notified from the roadside sensor 4, and execute the information processing of FIG. 5 based on the calculation result by itself.

[0082] Also, the determination in step ST12 of FIG. 5 may be executed by another roadside device such as a relay device (not shown). In this case, the control unit 31 of the traffic signal controller 3 may execute the extension of the all-red time (first detection control) or the termination of the pedestrian green time (second detection control) according to the determination result notified from another roadside device.

[0083] 〔Second Modification Example〕 In the above-described embodiment, when the control unit 31 of the traffic signal controller 3 executes the first detection control or the second detection control, the executed control result may be included in the signal control execution information and transmitted to the central device of the traffic control center. In this way, the control results of the first detection control and the second detection control become the management targets of the central device, and the control results can be used for cause analysis when a traffic accident occurs.

[0084] 〔Other Modification Examples〕 The above-described embodiments (including modification examples) are illustrative in all respects and not restrictive. The scope of the rights of the present invention includes all changes within the scope equivalent to the configuration described in the claims.

Explanation of Reference Numerals

[0085] 1 Vehicle lamp (signal lamp) 2 Pedestrian lamp (signal lamp) 3 Traffic signal controller 4 Roadside sensor 31 Control unit 32 Memory unit 33 Communication unit 34 Lamp driver 35 Computer program 41 Control unit 42 Memory unit 43 Communication unit 44 Roadside camera 45 Radar sensor 46 Computer program 100 Signal control system J Intersection R1 Main road R2 Secondary road L1 Inflow road (eastbound) L2 Inflow road (westbound) L3 Inflow road (southbound) L4 Inflow road (northbound)

Claims

1. A traffic signal control device comprising a control unit that acquires the arrival time of a vehicle passing through an inflow road to an intersection at the intersection, and executes a sensitive control to change the display time of a signal lamp device based on the acquired arrival time, wherein the signal lamp device, includes a vehicle lamp device that displays the presence or absence of the right of way for the vehicle passing through the inflow road, and the sensitive control, includes a first sensitive control for extending the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp device, a traffic signal control device.

2. The signal lamp device, includes a pedestrian lamp device that displays the right of way for pedestrians crossing the inflow road, and the sensitive control, includes a second sensitive control for cutting off the green time and starting a pedestrian green blink when the arrival time is included in the green time of the pedestrian lamp device, the traffic signal control device according to claim 1.

3. The control unit, when executing the first sensitive control or the second sensitive control, outputs a control command for operating a device that prompts at least one of the pedestrians and the vehicles to pay attention, the traffic signal control device according to claim 2.

4. The control unit, performs parallel processing of at least one of dilemma sensitive control, bus sensitive control, gap sensitive control, recall control, high-speed sensitive control, and FAST sensitive control and at least one of the first sensitive control and the second sensitive control, the traffic signal control device according to claim 2 or claim 3.

5. The control unit, when executing the first sensitive control or the second sensitive control, transmits the executed control content to a central device of a traffic control center, the traffic signal control device according to any one of claims 2 to 4.

6. A sensitive control method executed by a traffic signal control device, including the steps of acquiring the arrival time of a vehicle passing through an inflow road to an intersection at the intersection, and executing a sensitive control to change the display time of a signal lamp device based on the acquired arrival time, wherein the signal lamp device, includes a vehicle lamp device that displays the presence or absence of the right of way for the vehicle passing through the inflow road, and the sensitive control, includes a first sensitive control for extending the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp device, a sensitive control method.

7. ​ A computer program that causes a computer to function as a traffic signal controller including a control unit that acquires the arrival time of a vehicle passing through an inflow road to an intersection and performs sensitivity control to change the display time of a signal lamp based on the acquired arrival time. The signal lamp includes a vehicle lamp that displays the presence or absence of the right of way for the vehicle passing through the inflow road, The sensitivity control includes a computer program including first sensitivity control for extending the all-red time by a predetermined time when the arrival time is included in the all-red time of the vehicle lamp.

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