JP6902733B2 - Traffic signal control system, traffic signal control device, traffic signal control method, traffic signal control program, and terminal control device - Google Patents

Description

The present invention relates to a traffic signal control system, a traffic signal control device, a traffic signal control method, a traffic signal control program, a communication relay device, a communication relay method, and a communication relay program for controlling a plurality of signal lamps installed at an intersection. Is.

In the traffic signal control system, a terminal control device (traffic signal controller) that controls signal lights installed at intersections is installed near the signal lights, and terminal control is performed from a central control device installed at a traffic control center in a remote location. Send a signal control command to the device. Communication between the central control device and the terminal control device is performed by wire using a 3.4 kHz analog line, but since the wireless network (mobile communication network) has been developed in recent years, the central control device and the terminal control device are used. Communication between the control device and the terminal control device is being studied using a wireless network.

Assuming that wireless communication is used in such a traffic signal control system, the communication between the central control device of the traffic control center and the device of the police station is conventionally performed by WLL (subscriber wireless access system) or a wired line. As for the communication between the device of the police station and the terminal control device and the communication between the terminal control devices, a technique of controlling the communication by using the Internet routing technology is known as a wireless communication by a spread spectrum method or the like. (See Patent Document 1). This technique solves the problem that signal control becomes impossible when a trouble occurs in a line by multiplexing communication paths.

Japanese Patent No. 3456170

By the way, in the traffic signal control system, the central control device is periodically notified of the operation history information (signal operation execution information) indicating the operation status when the signal lamp is actually controlled in the terminal control device, and the central control device. Manages operation history information in. This operation history information is used for verification of traffic accidents and the like so that the state of the signal lamp on the day can be confirmed at a later date. For this reason, if the operation history information is lost, police operations will be hindered.

On the other hand, as described above, if the communication between the central control device and the terminal control device is wireless communication using a wireless network, it is certain that the number and time of disconnection of communication will increase as compared with wired communication. There is a problem that the operation history information that is viewed and stored in the central control device is likely to be lost.

Therefore, a technique for multiplexing communication paths as in the conventional technique is applied when the communication between the central control device and the terminal control device is wireless communication, and the communication path via the wireless network is duplicated. It is considered that the stability of communication can be improved by controlling the switching to the other communication path when an abnormality occurs in one of the communication paths.

However, by duplicating the communication path via the wireless network in this way and controlling the communication path to be switched according to the abnormality of the communication path, the number and time of disconnection of the communication can be reduced, but the communication It takes a considerable amount of time to switch routes, and it is not possible to eliminate the time when communication is disconnected, and it is inevitable that the operation history information stored in the central control device will be lost.

Therefore, the present invention provides a traffic signal control system, a traffic signal control device, and traffic that can keep the operation history information stored in the central control device in a state without loss even if a situation occurs in which communication is disconnected. The main purpose is to provide a signal control method, a traffic signal control program, a communication relay device, a communication relay method, and a communication relay program.

The traffic signal control system of the present invention is a traffic signal control system that controls a plurality of signal lamps installed at an intersection, and includes an information collecting device, a central control device, a terminal control device, a terminal side storage unit, and the like. A terminal-side wireless communication unit and an operation history retransmission control unit are provided, the information collecting device collects traffic condition information in the vicinity of the intersection, and the central control device collects the traffic collected by the information collecting device. Signal control information is generated based on the situation information, and the signal control information is transmitted to the terminal-side wireless communication unit, and the terminal-side wireless communication unit transmits the signal control information transmitted from the central control device. Received via the wireless network, the terminal control device controls the plurality of signal lamps based on the signal control information acquired from the terminal-side wireless communication unit, and the terminal control device actually controls the plurality of signal lamps in its own device. The operation history information regarding the start time of the cycle at the time of control and the execution time of each ladder is generated, and the terminal side storage unit accumulates the operation history information generated by the terminal control device for a predetermined period of time, and the terminal The side wireless communication unit transmits the operation history information generated by the terminal control device to the central control device via the wireless network, and the central control device obtains the operation from the terminal side wireless communication unit. The history information is accumulated in the own device, and further, the central control device sets the start time of the cycle included in the operation history information and the end time of the cycle calculated from the execution time of each ladder at a predetermined timing. Based on the consistency with the start time of the next cycle, it is confirmed whether or not the operation history information stored in the own device is missing, and if the operation history information is missing, the loss period is related. When the retransmission request including the information is transmitted to the terminal-side wireless communication unit, and the operation history retransmission control unit receives the retransmission request at the terminal-side wireless communication unit, the information regarding the loss period added to the retransmission request is added. Based on this, the operation history information included in the loss period is searched from the operation history information stored in the terminal-side storage unit, and the terminal-side wireless communication unit is acquired by the operation history retransmission control unit. When the operation history information is transmitted to the central control device via the wireless network, and the central control device receives the operation history information included in the loss period transmitted from the terminal-side wireless communication unit. , The operation history information is stored in the own device.

Further, the traffic signal control device of the present invention includes a communication unit that communicates with the terminal control device via the wireless network and the terminal side wireless communication unit, a storage unit, and a control unit, and the control unit is the control unit. When the operation history information regarding the cycle start time and the execution time of each ladder when the terminal control device actually controls a plurality of signal lamps is received from the terminal side wireless communication unit, the operation history information is stored in the storage unit. Accumulated and at a predetermined timing, based on the consistency between the cycle end time calculated from the cycle start time and the execution time of each ladder included in the operation history information and the start time of the next cycle. It is confirmed whether or not the operation history information stored in the storage unit is missing, and if the operation history information is missing, a retransmission request including information on the loss period is sent to the terminal side wireless communication unit. When the operation history information included in the loss period transmitted from the terminal-side wireless communication unit is received, the operation history information is stored in the storage unit.

Further, the communication relay device of the present invention includes a wireless communication unit that performs wireless communication with the central control device via a wireless network, a wired communication unit that performs wired communication with the terminal control device, and a storage unit. When the wired communication unit receives operation history information indicating an operation state when a plurality of signal lamps are actually controlled by the terminal control device, the control unit includes a control unit. , The operation history information is transmitted from the wireless communication unit to the central control device, the operation history information received from the terminal control device is stored in the storage unit for a predetermined period, and is stored in the central control device. When the retransmission request transmitted from the central control device is received when the operation history information is defective, the operation history information included in the deletion period is input based on the information regarding the deletion period added to the retransmission request. The operation history information stored in the storage unit is searched for, and the corresponding operation history information is transmitted from the wireless communication unit to the central control device.

According to the present invention, when there is a defect in the operation history information stored in the central control device, the operation history information corresponding to the defect period is retransmitted to the central control device. It is possible to repair the loss of the accumulated operation history information. As a result, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, in the central control device, in order to confirm whether or not the operation history information stored in the own device is missing based on the consistency between the end time of the cycle and the start time of the next cycle, the operation history information It is possible to accurately grasp the loss period of the operation history and appropriately repair the loss of the operation history information. In addition, since it is not necessary to install two wireless lines, it is possible to reduce the labor and cost of preparing two types of lines.

Overall configuration diagram of the traffic signal control system according to the first embodiment A sequence diagram showing an outline of processing performed by the terminal control device 3, the central control device 4, and the wireless conversion device 5 according to the first embodiment. Explanatory drawing which shows the content of the operation history notification message transmitted from the terminal control device 3 which concerns on 1st Embodiment to a central control device 4 via a wireless conversion device 5. Explanatory drawing which shows a specific example of the operation history information which is transmitted from the terminal control device 3 which concerns on 1st Embodiment and is stored in wireless conversion device 5. Explanatory drawing which shows specific example of operation history information stored in central control apparatus 4 which concerns on 1st Embodiment Explanatory drawing which shows the content of the message of the operation history retransmission request transmitted from the central control device 4 which concerns on 1st Embodiment Explanatory drawing which shows the content of the message of the operation history retransmission response transmitted from the wireless conversion apparatus 5 which concerns on 1st Embodiment A block diagram showing a schematic configuration of the terminal control device 3 according to the first embodiment. A block diagram showing a schematic configuration of the central control device 4 according to the first embodiment. A block diagram showing a schematic configuration of the wireless conversion device 5 according to the first embodiment. FIG. 5 is a flow chart showing a procedure of processing performed at the time of operation history transfer in the wireless conversion device 5 according to the first embodiment. The flow chart which shows the procedure of the process performed at the time of confirming the operation history defect in the central control device 4 which concerns on 1st Embodiment. The flow chart which shows the procedure of the process performed at the time of the operation history retransmission in the wireless conversion apparatus 5 which concerns on 1st Embodiment. The flow chart which shows the procedure of the process performed at the time of the operation history retransmission in the central control unit 4 which concerns on 1st Embodiment. Overall configuration diagram of the traffic signal control system according to the second embodiment A block diagram showing a schematic configuration of the terminal control device 101 according to the second embodiment.

The first invention made to solve the above problems is a traffic signal control system for controlling a plurality of signal lamps installed at an intersection, and includes an information collecting device, a central control device, a terminal control device, and the like. A terminal-side storage unit, a terminal-side wireless communication unit, and an operation history retransmission control unit are provided, the information collecting device collects traffic condition information in the vicinity of the intersection, and the central control device collects the information. Signal control information was generated based on the traffic condition information collected by the device, and the signal control information was transmitted to the terminal-side wireless communication unit, and the terminal-side wireless communication unit was transmitted from the central control device. The signal control information is received via the wireless network, and the terminal control device controls the plurality of signal lamps based on the signal control information acquired from the terminal side wireless communication unit, and the terminal control device actually controls the plurality of signal lamps in the own device. The operation history information regarding the start time of the cycle and the execution time of each ladder when the plurality of signal lamps are controlled is generated, and the terminal side storage unit uses the operation history information generated by the terminal control device for a predetermined period. The terminal-side wireless communication unit transmits the operation history information generated by the terminal control device to the central control device via the wireless network, and the central control device transmits the terminal-side wireless communication. The operation history information acquired from the unit is accumulated in the own device, and the central control device is calculated at a predetermined timing from the start time of the cycle included in the operation history information and the execution time of each of the steps. Based on the consistency between the end time of one cycle and the start time of the next cycle, it is confirmed whether or not the operation history information stored in the own device is missing, and if the operation history information is missing. Sends a retransmission request including information on the loss period to the terminal-side wireless communication unit, and when the operation history retransmission control unit receives the retransmission request at the terminal-side wireless communication unit, the retransmission request is added to the retransmission request. Based on the information regarding the loss period, the operation history information included in the loss period is searched from the operation history information stored in the terminal-side storage unit, and the terminal-side wireless communication unit performs the operation. The operation history information acquired by the history retransmission control unit is transmitted to the central control device via the wireless network, and the central control device is included in the loss period transmitted from the terminal-side wireless communication unit. When the operation history information is received, the operation history information is stored in the own device.

According to this, when the operation history information stored in the central control device is missing, the operation history information corresponding to the loss period is retransmitted to the central control device, so that the operation history information is stored in the own device in the central control device. It is possible to repair the loss of the operation history information. As a result, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, in the central control device, in order to confirm whether or not the operation history information stored in the own device is missing based on the consistency between the end time of the cycle and the start time of the next cycle, the operation history information It is possible to accurately grasp the loss period of the operation history and appropriately repair the loss of the operation history information. In addition, since it is not necessary to install two wireless lines, it is possible to reduce the labor and cost of preparing two types of lines.

The second invention is a traffic signal control method for controlling a plurality of signal lamps installed at an intersection, in which an information collecting device collects traffic condition information in the vicinity of the intersection, and a central control device provides a central control device. Signal control information is generated based on the traffic condition information collected by the information collecting device, the signal control information is transmitted to the terminal side wireless communication unit, and the terminal side wireless communication unit transmits from the central control device. The signal control information is received via the wireless network, and the terminal control device controls the plurality of signal lamps based on the signal control information acquired from the terminal side wireless communication unit, and the terminal control device actually controls the plurality of signal lamps. The operation history information regarding the start time of the cycle and the execution time of each ladder when the plurality of signal lamps are controlled is generated, and the terminal side storage unit uses the operation history information generated by the terminal control device for a predetermined period. The terminal-side wireless communication unit transmits the operation history information generated by the terminal control device to the central control device via the wireless network, and the central control device transmits the terminal-side wireless communication. The operation history information acquired from the unit is accumulated in the own device, and the central control device is calculated at a predetermined timing from the start time of the cycle included in the operation history information and the execution time of each of the steps. Based on the consistency between the end time of one cycle and the start time of the next cycle, it is confirmed whether or not the operation history information stored in the own device is missing, and if the operation history information is missing. Is transmitted to the terminal side wireless communication unit, and when the operation history retransmission control unit receives the retransmission request at the terminal side wireless communication unit, it is added to the retransmission request. Based on the information regarding the loss period, the operation history information included in the loss period is searched from the operation history information stored in the terminal side storage unit, and the terminal side wireless communication unit searches for the operation history. The operation history information acquired by the retransmission control unit is transmitted to the central control device via the wireless network, and the central control device is included in the loss period transmitted from the terminal-side wireless communication unit. When the history information is received, the operation history information is stored in the own device.

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

The third invention includes a communication unit that communicates with the terminal control device via the wireless network and the terminal side wireless communication unit, a storage unit, and a control unit, and the control unit is the terminal control device. When the operation history information regarding the cycle start time and the execution time of each ladder when the plurality of signal lamps are actually controlled is received from the terminal-side wireless communication unit, the operation history information is accumulated in the storage unit. At a predetermined timing, the storage unit is based on the consistency between the start time of the cycle included in the operation history information, the end time of the cycle calculated from the execution time of each ladder, and the start time of the next cycle. It is confirmed whether or not the operation history information accumulated in the operation history information is missing, and if the operation history information is missing, a retransmission request including information on the loss period is transmitted to the terminal side wireless communication unit. When the operation history information included in the loss period transmitted from the terminal-side wireless communication unit is received, the operation history information is stored in the storage unit.

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

Further, in the fourth invention, the operation history information regarding the cycle start time and the execution time of each ladder when the terminal control device actually controls a plurality of signal lamps is transmitted from the terminal side wireless communication unit via the wireless network. Upon receipt, the operation history information is accumulated in the own device, and at a predetermined timing, the cycle end time calculated from the cycle start time included in the operation history information and the execution time of each ladder and the next cycle Based on the consistency with the start time of, it is confirmed whether or not the operation history information stored in the own device is missing, and if the operation history information is missing, the information regarding the missing period is included. When a retransmission request is transmitted to the terminal-side wireless communication unit and the operation history information included in the loss period transmitted from the terminal-side wireless communication unit is received, the operation history information is stored in the own device. ..

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

The fifth invention is a traffic signal control program for causing a computer to execute the above-mentioned traffic signal control method.

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

Further, the sixth invention is a control of a wireless communication unit that performs wireless communication with a central control device via a wireless network, a wired communication unit that performs wired communication with a terminal control device, a storage unit, and a storage unit. When the wired communication unit receives operation history information indicating an operation state when a plurality of signal lamps are actually controlled by the terminal control device, the control unit includes a unit and the unit. The operation history information is transmitted from the wireless communication unit to the central control device, the operation history information received from the terminal control device is stored in the storage unit for a predetermined period, and the operation stored in the central control device is stored. When a retransmission request transmitted from the central control device is received when the history information has a defect, the operation history information included in the deletion period is transmitted to the operation history information included in the deletion period based on the information regarding the deletion period added to the retransmission request. The operation history information stored in the storage unit is searched for, and the corresponding operation history information is transmitted from the wireless communication unit to the central control device.

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

Further, in the seventh invention, when the wired communication unit receives the operation history information indicating the operation status when the terminal control device actually controls a plurality of signal lamps, the operation history information is wirelessly transmitted. When the operation history information transmitted from the communication unit to the central control device and received from the terminal control device is stored in the own device for a predetermined period, and the operation history information stored in the central control device is missing. When the retransmission request transmitted from the central control device is received, the operation history information included in the defect period is stored in the own device based on the information regarding the defect period added to the retransmission request. It is configured to search from the information and transmit the corresponding operation history information from the wireless communication unit to the central control device.

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

Further, the eighth invention is a traffic signal control program for causing a computer to execute the above-mentioned traffic signal control method.

According to this, as in the first invention, even if a situation occurs in which communication is disconnected, the operation history information stored in the central control device can be maintained in a state without loss. Further, as in the first invention, it is not necessary to install two wireless lines, so that it is possible to reduce the labor and cost of preparing two types of lines.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment)
FIG. 1 is an overall configuration diagram of a traffic signal control system according to the first embodiment.

The traffic signal control system controls a plurality of signal lamps 1 installed at an intersection, and includes a vehicle detector 2, a terminal control device 3, a central control device 4 (traffic signal control device, computer), and radio. It is equipped with a conversion device 5 (communication relay device, computer).

The vehicle detector 2 is installed on the road, detects a vehicle on the road, and generates vehicle detector information (traffic condition information) indicating the traffic condition of the vehicle on the road. This vehicle detector information is transmitted from the vehicle detector 2 to the terminal control device 3. In addition to being used for control by the terminal control device 3, the vehicle detector information is transmitted to the central control device 4 via the wireless conversion device 5 and used for control by the central control device 4.

The terminal control device 3 (traffic signal controller) is installed in the vicinity of the signal lamp device 1, and is a signal lamp device based on a signal control command (signal control information) transmitted from the central control device 4 via the wireless conversion device 5. 1 is controlled. Further, the terminal control device 3 periodically transmits the operation history information (signal operation execution information) indicating the operation status when the signal lamp 1 is actually controlled to the central control device 4.

The central control device 4 is installed in the traffic control center and generates a signal control command (signal control information) for controlling the signal lamp 1 based on the vehicle detector information transmitted from the vehicle detector 2 and the like. The signal control command is transmitted to the terminal control device 3 via the wireless conversion device 5.

In the present embodiment, the central control device 4 uses the vehicle detector information to perform signal control, but the information collecting device such as the ITS spot, the optical beacon, and the radio beacon installed on the road is used. Signal control may be performed using the collected traffic condition information.

The wireless conversion device 5 is installed in the vicinity of the terminal control device 3 and enables communication between the terminal control device 3 and the central control device 4 corresponding to a wired analog line in a wireless network (mobile) such as LTE (Long Term Evolution). To be able to do it via the communication network).

Next, the outline of the processing performed by the terminal control device 3, the central control device 4, and the wireless conversion device 5 according to the first embodiment will be described. FIG. 2 is a sequence diagram showing an outline of processing performed by the terminal control device 3, the central control device 4, and the wireless conversion device 5.

As shown in FIG. 2A, the central control device 4 generates a signal control command (signal control information) based on the traffic condition information collected by the vehicle detector 2, and issues the signal control command to the terminal control device. Send toward 3. When the wireless conversion device 5 receives the signal control command transmitted from the central control device 4 via the wireless network, the wireless conversion device 5 transfers the signal control command to the terminal control device 3. The terminal control device 3 controls a plurality of signal lamps 1 based on a signal control command acquired from the central control device 4 via the wireless conversion device 5, and when the own device actually controls the plurality of signal lamps 1. The operation history information representing the operation status is generated, and the operation history notification message including the operation history information is transmitted to the wireless conversion device 5. The wireless conversion device 5 transfers the operation history notification message from the terminal control device 3 to the central control device 4 via the wireless network. Further, the wireless conversion device 5 stores the operation history information included in the operation history notification message in its own device for a predetermined period of time. When the central control device 4 receives the operation history notification message from the terminal control device 3, the central control device 4 stores the operation history information included in the operation history notification message in its own device.

Further, as shown in FIG. 2B, the central control device 4 confirms whether or not the operation history information stored in the own device is missing at a predetermined timing, and when the operation history information is missing. Sends a message of an operation history retransmission request including information on the loss period to the wireless conversion device 5. When the wireless conversion device 5 receives the operation history retransmission request message, the wireless conversion device 5 stores the operation history information included in the loss period in its own device based on the information regarding the loss period added to the operation history retransmission request message. The operation history information is searched for, and the operation history retransmission response message including the corresponding operation history information is transmitted to the central control device 4 via the wireless network. When the central control device 4 receives the operation history retransmission response message from the wireless conversion device 5, it accumulates the operation history information included in the operation history retransmission response message in its own device, and the operation accumulated in its own device. Repair missing historical information.

Next, the operation history notification message transmitted from the terminal control device 3 according to the first embodiment to the central control device 4 via the wireless conversion device 5 will be described. FIG. 3 is an explanatory diagram showing the content of the operation history notification message.

When one cycle is completed, the terminal control device 3 sends an operation history notification message including operation history information (signal operation execution information) for one cycle indicating the content of the control executed in that cycle to the wireless conversion device 5. It is transmitted to the central control device 4 via.

The operation history notification message includes a header indicating that this message includes operation history information (signal operation execution information), a start time (hours, minutes, seconds) of the target cycle, and is added to the target cycle. The serial number and the number of execution seconds (execution time) for each step in the target cycle are stored.

Next, the loss of the operation history information transmitted from the terminal control device 3 according to the first embodiment and stored in the central control device 4 will be described. FIG. 4 is an explanatory diagram showing a specific example of operation history information transmitted from the terminal control device 3 and stored in the wireless conversion device 5. FIG. 5 is an explanatory diagram showing a specific example of the operation history information stored in the central control device 4. In addition, the example shown in FIGS. 4 and 5 is a case of basic control of the number of steps of 10 in 2 representations.

Since a wireless network is involved in the communication between the wireless conversion device 5 and the central control device 4, communication disconnection is likely to occur, and when the communication disconnection occurs, the cycle unit transmitted from the wireless conversion device 5 The operation history information of is not received by the central control device 4. Therefore, in the central control device 4, the operation history information for each cycle stored in the own device is missing.

Therefore, in the present embodiment, in the central control device 4, it is confirmed whether or not there is a defect in the operation history information stored in the own device. Whether or not the operation history information is missing is confirmed, for example, once a day. Then, when the operation history information is missing, the wireless conversion device 5 is requested to retransmit the insufficient operation history information, and the missing operation history information is transmitted to the wireless conversion device 5. By acquiring from, the loss of operation history information can be repaired.

Here, in the central control device 4, the time required for the operation of one cycle, that is, the cycle length (cycle seconds) is added to the cycle start time to calculate the cycle end time. Then, the end time of the cycle of interest and the start time of the next cycle are compared, and if they do not match, it is determined that there is a defect between the cycle of interest and the next cycle. Further, since the operation history information transmitted from the terminal control device 3 does not include the cycle length, the central control device 4 calculates the cycle length by summing the execution time (execution seconds) of each step in one cycle. calculate.

In the example shown in FIG. 5, the end time of the cycle of No. 1, that is, the time (9:53:20) obtained by adding the cycle length (100 seconds) to the start time (9:51:40) is No. 2. Since it is consistent with the start time of the cycle of No. 1, there is no loss between the cycle of No. 1 and the cycle of No. 2. Similarly, there is no deficiency between the number 2 cycle and the number 3 cycle, and there is no deficiency between the number 3 cycle and the number 4 cycle. However, the end time of the cycle of number 4, that is, the time (9:58:20) obtained by adding the cycle length (100 seconds) to the start time (9:56:40) is the start time of the cycle of number 5. Since it is inconsistent with (10:08:40), there is a defect between the cycle of number 4 and the cycle of number 5.

Further, in the present embodiment, when it is determined that there is a defect between the two cycles before and after, the information regarding the defect period is transmitted to the wireless conversion device 5 and stored in the own device in the wireless conversion device 5. The operation history information of the cycle corresponding to the missing period is searched from the operation history information of each cycle. At this time, in the present embodiment, the missing data search start time and the missing data search end time are transmitted to the wireless converter 5 as information regarding the missing period.

Here, the end time of the previous cycle of the two cycles in which the inconsistency is found is set as the missing search start time. In the example shown in FIG. 5, the end time of the cycle of number 4, that is, the time (9:58:20) obtained by adding the cycle length (100 seconds) to the start time (9:56:40) is the missing search. Set to start time. Also, the time immediately before the start time of the later cycle is set as the missing search end time. Specifically, the time obtained by subtracting 1 second from the start time of the later cycle is set as the missing search end time. In the example shown in FIG. 5, the time (10: 8: 39) obtained by subtracting 1 second from the start time (10: 8: 40) of the cycle of No. 5 is set as the missing data search end time.

The signal lamp 1 in the terminal control device 3 is controlled in units of 0.1 seconds, but the execution time (number of execution seconds) of each ladder included in the operation history information is in units of 1 second. Therefore, even if there is no loss between the cycle of interest and the next cycle, the end time of the cycle, that is, the time obtained by adding the cycle length to the start time of the cycle, exactly matches the start time of the next cycle. It may not be. Therefore, if the error between the end time of the cycle of interest and the start time of the next cycle is within the permissible range (for example, several seconds), it is determined that the two are consistent.

Next, the operation history retransmission request message transmitted from the central control device 4 according to the first embodiment will be described. FIG. 6 is an explanatory diagram showing the content of the operation history retransmission request message.

When the central control device 4 finds a defect in the operation history information for each cycle stored in the own device, the central control device 4 transmits a message of an operation history retransmission request to the wireless conversion device 5.

This operation history retransmission request message includes a header indicating that this message requests the retransmission of operation history information (missing signal operation execution information request command), and information regarding the range of the missing period. The missing search start time (hours, minutes, seconds) and the missing search end time (hours, minutes, seconds) are stored.

When the wireless conversion device 5 receives the operation history retransmission request message from the central control device 4, the missing period is set based on the missing search start time and the missing search end time included in the operation history retransmission request message. Search for the corresponding operation history information from the operation history information stored in the own device. Specifically, when the cycle start time is included between the missing data search start time and the missing data search end time, it is determined that the cycle corresponds to the missing period.

In the example shown in FIG. 4, the cycle of numbers 5 to 9 is included between the missing data search start time (9:58:20) and the missing data search end time (10: 8: 39). Therefore, it is determined that the cycle of No. 5 to No. 9 corresponds to the loss period.

Next, the operation history retransmission response message transmitted from the wireless conversion device 5 according to the first embodiment will be described. FIG. 7 is an explanatory diagram showing the content of the operation history retransmission response message.

When the wireless conversion device 5 finds the operation history information corresponding to the missing period by the search process, the wireless conversion device 5 transmits a message of an operation history retransmission response including the operation history information to the central control device 4.

The operation history retransmission response message includes a header indicating that this message includes operation history information (missing signal operation execution information) corresponding to the missing period of the operation history information stored in the central control device 4. The start time (hours, minutes, seconds) of the target cycle, the serial number assigned to the target cycle, and the number of execution seconds (execution time) for each step in the target cycle are stored.

Next, a schematic configuration of the terminal control device 3 according to the first embodiment will be described. FIG. 8 is a block diagram showing a schematic configuration of the terminal control device 3.

The terminal control device 3 includes a wired communication unit 21, an input / output unit 22, a storage unit 23, and a control unit 24.

The wired communication unit 21 performs wired communication with the wireless conversion device 5. Specifically, a signal control command (signal control information) is received from the wireless converter 5. This signal control command is transmitted from the central control device 4 to the wireless conversion device 5. Further, the wired communication unit 21 transmits the operation history information to the wireless conversion device 5. This operation history information is transmitted from the wireless conversion device 5 to the central control device 4. Further, the wired communication unit 21 inputs / outputs an analog signal corresponding to a 3.4 kHz analog line.

The input / output unit 22 inputs / outputs information between the signal lamp 1 and the vehicle detector 2. Specifically, the control information is output to the signal lamp 1, and the vehicle detection information output from the vehicle detector 2 is input.

The storage unit 23 stores a program executed by the processors constituting the control unit 24. Further, the signal control command (signal control information) acquired from the central control device 4 via the wireless conversion device 5 is stored.

The control unit 24 includes a signal lamp control unit 31 and an operation history notification unit 32. The control unit 24 is composed of a processor, and each unit of the control unit 24 is realized by executing a program stored in the storage unit 23 by the processor.

The signal lamp control unit 31 controls the signal lamp 1 based on the signal control command (signal control information) acquired from the central control device 4.

The operation history notification unit 32 generates operation history information (signal operation execution information) for each cycle, and transmits the operation history information for each cycle from the wired communication unit 21 to the central control device 4 via the wireless conversion device 5. To do. At this time, at the timing when one cycle is completed, the operation history information (cycle start time, execution time of each step, etc.) related to the cycle is transmitted one by one.

Next, a schematic configuration of the central control device 4 according to the first embodiment will be described. FIG. 9 is a block diagram showing a schematic configuration of the central control device 4.

The central control device 4 includes a communication unit 41, a storage unit 42, and a control unit 43.

The communication unit 41 communicates with the wireless conversion device 5 via the mobile communication network. Specifically, the signal control command is transmitted to the terminal control device 3 via the wireless conversion device 5. Further, the operation history information transmitted from the terminal control device 3 is received via the wireless conversion device 5.

The storage unit 42 stores a program executed by the processor constituting the control unit 43. Further, the storage unit 42 stores the operation history information acquired from the terminal control device 3 via the wireless conversion device 5.

The control unit 43 includes a signal control command generation unit 51, an operation history defect confirmation unit 52, an operation history retransmission request unit 53, and an operation history defect repair unit 54. It is composed of the control unit 43 processor, and each unit of the control unit 43 is realized by executing the program stored in the storage unit 42 by the processor.

The signal control command generation unit 51 generates a signal control command (signal control information), specifically, control parameters (cycle length, split, offset).

The operation history deficiency confirmation unit 52 determines whether or not the operation history information stored in the storage unit 42 is deficient based on the consistency of the time information regarding the start and end of the cycle, and the operation history information is deficient. If so, get the deficiency period. This operation history defect confirmation process is performed periodically, for example, once a day at a predetermined execution timing.

The operation history retransmission request unit 53 transmits a message of the operation history retransmission request from the communication unit 41 to the wireless conversion device 5. This operation history retransmission request message requests the wireless converter 5 to retransmit the operation history information corresponding to the missing period, and the operation history retransmission request message includes information on the missing period (missing). Includes measurement search start time and missing search end time).

When the communication unit 41 receives the operation history retransmission response message, the operation history loss repair unit 54 stores the operation history information included in the operation history retransmission response message in the storage unit 42 for a period of loss of the operation history information. Insert it in to repair the loss of operation history information.

Next, a schematic configuration of the wireless conversion device 5 according to the first embodiment will be described. FIG. 10 is a block diagram showing a schematic configuration of the wireless conversion device 5.

The wireless conversion device 5 includes a wired communication unit 61, a wireless communication unit 62 (terminal side wireless communication unit), a storage unit 63 (terminal side storage unit), and a control unit 64.

The wired communication unit 61 communicates with the terminal control device 3. In the terminal control device 3, an analog signal suitable for a 3.4 kHz analog line is input / output, and the wired communication unit 61 includes an analog signal on the terminal control device 3 side and a digital signal on the control unit 64 side (for example, RS232C signal). Consists of a modem that performs the conversion of.

The wireless communication unit 62 communicates with the central control device 4 via a wireless network. The wireless communication unit 62 includes a wireless module and an antenna that convert a digital signal (for example, a LAN signal) on the control unit 64 side and a wireless radio wave signal on the wireless network side.

The storage unit 63 stores a program executed by the processor constituting the control unit 64. In addition, the storage unit 63 stores the operation history information for each cycle acquired from the terminal control device 3.

The control unit 64 includes a control command transfer unit 71, an operation history transfer unit 72, an operation history management unit 73, and an operation history retransmission control unit 74. The control unit 64 is composed of a processor, and each unit of the control unit 64 is realized by executing the program stored in the storage unit 63 by the processor.

When the wireless communication unit 62 receives the signal control command from the central control device 4, the control command transfer unit 71 transfers the signal control command from the wired communication unit 61 to the terminal control device 3.

When the operation history transfer unit 72 receives the operation history information from the terminal control device 3 by the wired communication unit 61, the operation history transfer unit 72 transfers the operation history information from the wireless communication unit 62 to the central control device 4.

When the operation history management unit 73 receives the operation history information from the terminal control device 3, the operation history management unit 73 stores the operation history information in the storage unit 63. Here, the storage unit 63 stores a predetermined number of cycle-based operation history information (signal operation execution information) (for example, 3000), and the operation history management unit 73 receives the cycle-based operation history from the terminal control device 3. By storing the new operation history information by overwriting each time the information is received one by one, the latest operation history information of a predetermined number of cases is always stored in the storage unit 63. Assuming that the cycle length is 60 seconds, the operation history information for each cycle becomes 1140 in one day, and 3000 cases can accumulate operation history information for more than two days.

When the operation history retransmission control unit 74 receives the operation history retransmission request message, the operation history retransmitting request message includes an operation history corresponding to the condition related to the loss period included in the operation history retransmission request message from the operation history information stored in the storage unit 63. The information is searched from the operation history information stored in the storage unit 63, and the operation history retransmission response message including the operation history information is transmitted from the wireless communication unit 62 to the central control device 4.

Next, a procedure of processing performed at the time of operation history transfer in the wireless conversion device 5 will be described. FIG. 11 is a flow chart showing a procedure of processing performed at the time of operation history transfer in the wireless conversion device 5.

In the wireless conversion device 5, first, the identification number n for identifying the target cycle is initialized (n = 0) (ST101). Next, it is determined whether or not the operation history information (signal operation execution information) for each cycle is received from the terminal control device 3 (ST102).

Here, when the operation history information of the cycle unit is received (Yes in ST102), the operation history notification message including the operation history information of the cycle unit is transmitted from the wireless communication unit 62 to the central control device 4 (Yes). ST103).

Next, the operation history information for each cycle received from the terminal control device 3 is stored in the storage unit 63 as the nth operation history information (ST104).

Next, the identification number n is incremented by 1 (n = n + 1) (ST105). Then, it is determined whether or not the identification number n is equal to or greater than the upper limit value (n ≧ 3000) (ST106).

Here, if the identification number n is not equal to or greater than the upper limit value (No in ST106), the process returns to ST102. On the other hand, if the identification number n is equal to or greater than the upper limit value (Yes in ST106), the process returns to ST101.

In this way, the wireless conversion device 5 transfers the operation history information (signal operation execution information) for each cycle received from the terminal control device 3 to the central control device 4 one by one. In addition, a predetermined number of cycle-based operation history information received from the terminal control device 3 is stored in the own device. At this time, each time the operation history information for each cycle is received from the terminal control device 3 one by one, the new operation history information is overwritten and stored, so that a predetermined number of the latest operation history information is always accumulated.

Next, the procedure of the processing performed when the operation history defect is confirmed in the central control device 4 will be described. FIG. 12 is a flow chart showing a procedure of processing performed when the operation history defect is confirmed in the central control device 4.

The central control device 4 first determines whether or not the current operation history loss confirmation is the execution timing (ST201). When the operation history defect confirmation is performed once a day, for example, the time when the date changes may be set as the operation history defect confirmation execution timing.

Here, if the current timing is the execution timing of the operation history loss confirmation (Yes in ST201), then the operation history information of the target period is sorted in ascending order based on the cycle start time (yes). ST202). When the operation history defect confirmation is performed once a day, the target period is one day on the previous day.

Next, the identification number n that identifies the target cycle is initialized (n = 0) (ST203). Next, it is determined whether or not there is a defect between the nth cycle and the n + 1th cycle (ST204). At this time, the time obtained by adding the cycle length of the nth cycle to the start time of the nth cycle is calculated as the end time of the nth cycle, and the end time of the nth cycle and the start of the n + 1th cycle. If the times do not match, it is determined that there is a defect.

Here, if there is a defect between the nth cycle and the n + 1th cycle (Yes in ST204), the period between the end time of the nth cycle and the time immediately before the start time of the n + 1th cycle. Is set as the loss period (ST205). At this time, the time obtained by subtracting 1 second from the start time of the n + 1th cycle is calculated as the immediately preceding time.

Next, the identification number n is incremented by 1 (n = n + 1) (ST206). Then, it is determined whether or not the operation history loss confirmation is completed for all the operation history information for each cycle included in the target period (ST207).

Here, if the defect confirmation has not been completed for all of the operation history information for each cycle included in the target period (No in ST207), the process returns to ST204.

On the other hand, when the defect confirmation is completed for all the operation history information for each cycle included in the target period (Yes in ST207), then it is determined whether or not the defect period is set (ST208).

Here, when the loss period is set (Yes in ST208), then a message of an operation history retransmission request including information about the loss period is transmitted from the communication unit 41 to the wireless conversion device 5 (ST209).

Next, the procedure of the process performed at the time of retransmitting the operation history in the wireless conversion device 5 will be described. FIG. 13 is a flow chart showing a procedure of processing performed when the operation history is retransmitted in the wireless conversion device 5.

The wireless conversion device 5 first determines whether or not a message of an operation history retransmission request has been received from the central control device 4 (ST301).

Here, when the message of the operation history retransmission request is received (Yes in ST301), the identification number n for identifying the target cycle is initialized (n = 0) (ST302). Next, it is determined whether or not the nth cycle corresponds to the missing period included in the operation history retransmission request message (ST303).

Here, when the nth cycle corresponds to the loss period (Yes in ST303), the operation history retransmission response message including the operation history information of the nth cycle is sent from the wireless communication unit 62 to the central control device 4. Transmit (ST304).

Next, the identification number n is incremented by 1 (n = n + 1) (ST305). Then, it is determined whether or not the identification number n is equal to or greater than the upper limit value (n ≧ 3000) (ST306).

Here, if the identification number n is not equal to or greater than the upper limit value (No in ST306), the process returns to ST303. On the other hand, if the identification number n is equal to or greater than the upper limit value (Yes in ST306), the process returns to ST301.

In this way, when the central control device 4 requests retransmission, the wireless conversion device 5 obtains one cycle-based operation history information corresponding to the loss period from the cycle-based operation history information stored in the own device. It is transmitted to the central control device 4 one by one.

Next, the procedure of the processing performed at the time of retransmitting the operation history in the central control device 4 will be described. FIG. 14 is a flow chart showing a procedure of processing performed when the operation history is retransmitted in the central control device 4.

The central control device 4 first determines whether or not a message of an operation history retransmission response has been received from the wireless conversion device 5 (ST401).

Here, when the operation history retransmission response message is received (Yes in ST401), the operation history information included in the operation history retransmission response message is inserted into the loss period of the operation history information stored in the own device. Defect repair processing is performed (ST402).

In this way, in the central control device 4, when the operation history information corresponding to the loss period is acquired from the wireless conversion device 5, the operation history information accumulated in the own device is to be repaired by the operation history information. Can be maintained in a state without defects.

As described above, in the present embodiment, in order to convert the wired communication of the terminal control device 3 corresponding to the 3.4 kHz analog line into wireless communication via the wireless network (mobile communication network), the wireless conversion device 5 is used as a terminal. Since it is connected to the control device 3, the terminal control device 3 itself can be updated to a system using a wireless network without modification.

(Second Embodiment)
Next, the second embodiment will be described. It should be noted that the points not particularly mentioned here are the same as those in the above-described embodiment. FIG. 15 is an overall configuration diagram of the traffic signal control system according to the second embodiment.

In the first embodiment, a wireless conversion device 5 capable of communicating using a wireless network (mobile communication network) is connected to a terminal control device 3 (traffic signal controller), and the central control device 4 and the terminal control device 3 are connected. Communication between the two is performed via the wireless network and the wireless conversion device 5, but in the present embodiment, the terminal control device 101 is configured to enable wireless communication using the wireless network, and is a central control device. The communication between 4 and the terminal control device 101 is directly performed via the wireless network.

Next, a schematic configuration of the terminal control device 101 according to the second embodiment will be described. FIG. 16 is a block diagram showing a schematic configuration of the terminal control device 101.

The terminal control device 101 includes a wireless communication unit 111 (terminal side wireless communication unit). The wireless communication unit 111 communicates with the central control device 4 via a wireless network. The wireless communication unit 111 is composed of a wireless module and an antenna that convert a digital signal (for example, a LAN signal) on the control unit 113 side and a wireless radio wave signal on the wireless network side. Two wireless communication units 111 are provided so that different wireless networks can be used.

The storage unit 112 (terminal side storage unit) of the terminal control device 101 accumulates operation history information for each cycle in the past predetermined period.

The control unit 113 of the terminal control device 101 includes an operation history management unit 121 and an operation history retransmission control unit 122 in addition to the signal lamp control unit 31 and the operation history notification unit 32.

The operation history management unit 121 stores the operation history information (signal operation execution information) of the cycle in the storage unit 112 each time one cycle is completed. The storage unit 112 stores operation history information for each cycle for a predetermined number (for example, 3000), and the operation history management unit 121 overwrites the operation history information of that cycle each time one cycle ends. By doing so, the latest operation history information of a predetermined number of cases is constantly accumulated in the storage unit 112.

When the operation history retransmission control unit 122 receives the operation history retransmission request message from the central control device 4, the operation history retransmission control unit 122 relates to the missing period included in the operation history retransmission request message from the operation history information stored in the storage unit 23. The operation history information corresponding to the condition is searched, and the operation history retransmission response message including the operation history information is transmitted.

The central control device is the same as that of the first embodiment (see FIG. 9).

As described above, embodiments have been described as examples of the techniques disclosed in this application. However, the technique in the present disclosure is not limited to this, and can be applied to embodiments in which changes, replacements, additions, omissions, etc. have been made. It is also possible to combine the components described in the above embodiments to form a new embodiment.

The traffic signal control system, the traffic signal control device, the traffic signal control method, the traffic signal control program, the communication relay device, the communication relay method, and the communication relay program according to the present invention can be used even if communication is disconnected. A traffic signal control system, a traffic signal control device, and a traffic signal that have the effect of keeping the operation history information accumulated in the central control device in a state without loss and controlling a plurality of signal lamps installed at intersections. It is useful as a control method, a traffic signal control program, a communication relay device, a communication relay method, a communication relay program, and the like.

1 Signal lighter 2 Vehicle detector 3 Terminal control device 4 Central control device (traffic signal control device, computer)
5 Wireless converter (communication relay device, computer)
21 Wired communication unit 22 Input / output unit 23 Storage unit 24 Control unit 31 Signal lamp control unit 32 Operation history notification unit 41 Communication unit 42 Storage unit 43 Control unit 51 Signal control command generation unit 52 Operation history loss confirmation unit 53 Operation history retransmission request Unit 54 Operation history loss repair unit 61 Wired communication unit 62 Wireless communication unit (terminal side wireless communication unit)
63 Storage unit (terminal storage unit)
64 Control unit 71 Control command transfer unit 72 Operation history transfer unit 73 Operation history management unit 74 Operation history retransmission control unit 101 Terminal control device 111 Wireless communication unit (terminal side wireless communication unit)
112 Storage unit (terminal storage unit)
113 Control unit 121 Operation history management unit 122 Operation history retransmission control unit

Claims (6)

A traffic signal control system that controls multiple signal lights installed at intersections.
It includes an information collecting device, a central control device, a terminal control device, a terminal side storage unit, a terminal side wireless communication unit, and an operation history retransmission control unit.
The information collecting device collects traffic condition information in the vicinity of the intersection and collects traffic condition information.
The central control device generates signal control information based on the traffic condition information collected by the information collecting device, and transmits the signal control information to the terminal side wireless communication unit.
The terminal-side wireless communication unit receives the signal control information transmitted from the central control device via the wireless network, and receives the signal control information.
The terminal control device controls the plurality of signal lamps based on the signal control information acquired from the terminal-side wireless communication unit, and the cycle start time when the own device actually controls the plurality of signal lamps. And generate operation history information about the execution time of each ladder,
The terminal-side storage unit accumulates the operation history information generated by the terminal control device for a predetermined period of time.
The terminal-side wireless communication unit transmits the operation history information generated by the terminal control device to the central control device via the wireless network.
The central control device stores the operation history information acquired from the terminal-side wireless communication unit in its own device.
Further, the central control device matches the start time of the cycle included in the operation history information and the end time of the cycle calculated from the execution time of each ladder with the start time of the next cycle at a predetermined timing. Based on the nature, it is confirmed whether or not the operation history information stored in the own device is missing, and if the operation history information is missing, a retransmission request including information on the missing period is sent to the terminal side. Send to the wireless communication section,
When the terminal-side wireless communication unit receives the retransmission request, the operation history retransmission control unit obtains the operation history information included in the deletion period based on the information regarding the deletion period added to the retransmission request. Search from the operation history information stored in the terminal storage unit,
The terminal-side wireless communication unit transmits the operation history information acquired by the operation history retransmission control unit to the central control device via the wireless network.
The central control device is a traffic signal control system characterized in that when it receives the operation history information included in the loss period transmitted from the terminal-side wireless communication unit, the central control device stores the operation history information in its own device. It is a traffic signal control method that controls multiple signal lights installed at intersections.
The information collecting device collects traffic condition information in the vicinity of the intersection and
The central control device generates signal control information based on the traffic condition information collected by the information collecting device, and transmits the signal control information to the terminal side wireless communication unit.
The terminal-side wireless communication unit receives the signal control information transmitted from the central control device via the wireless network, and receives the signal control information.
The cycle start time and the cycle start time when the terminal control device controls the plurality of signal lamps based on the signal control information acquired from the terminal-side wireless communication unit and actually controls the plurality of signal lamps in the own device. Generates operation history information about the execution time of each ladder,
The terminal-side storage unit accumulates the operation history information generated by the terminal control device for a predetermined period of time.
The terminal-side wireless communication unit transmits the operation history information generated by the terminal control device to the central control device via the wireless network.
The central control device accumulates the operation history information acquired from the terminal-side wireless communication unit in its own device.
Further, the central control device matches the start time of the cycle included in the operation history information and the end time of the cycle calculated from the execution time of each ladder with the start time of the next cycle at a predetermined timing. Based on the nature, it is confirmed whether or not the operation history information stored in the own device is missing, and if the operation history information is missing, a retransmission request including information on the missing period is sent to the terminal side. Send to the wireless communication section,
When the operation history retransmission control unit receives the retransmission request at the terminal-side wireless communication unit, the terminal receives the operation history information included in the deletion period based on the information regarding the deletion period added to the retransmission request. Search from the operation history information stored in the side storage unit,
The terminal-side wireless communication unit transmits the operation history information acquired by the operation history retransmission control unit to the central control device via the wireless network.
A traffic signal control method, characterized in that, when the central control device receives the operation history information included in the loss period transmitted from the terminal-side wireless communication unit, the operation history information is stored in the own device. A communication unit that communicates with the terminal control device via the wireless network and the terminal side wireless communication unit,
Memory and
With a control unit
The control unit
When the operation history information regarding the cycle start time and the execution time of each floor when the terminal control device actually controls a plurality of signal lamps is received from the terminal side wireless communication unit, the operation history information is stored in the storage unit. Accumulate in
At a predetermined timing, the storage unit is based on the consistency between the start time of the cycle included in the operation history information, the end time of the cycle calculated from the execution time of each ladder, and the start time of the next cycle. Check if there is any loss in the operation history information accumulated in
If the operation history information is missing, a retransmission request including information about the missing period is transmitted to the terminal-side wireless communication unit.
A traffic signal control device characterized in that when the operation history information included in the loss period transmitted from the terminal-side wireless communication unit is received, the operation history information is stored in the storage unit. When the operation history information regarding the cycle start time and the execution time of each floor when the terminal control device actually controls a plurality of signal lamps is received from the terminal side wireless communication unit via the wireless network, the operation history information is received. Accumulate in own device,
At a predetermined timing, based on the consistency between the start time of the cycle included in the operation history information, the end time of the cycle calculated from the execution time of each ladder, and the start time of the next cycle, the own device Check whether the accumulated operation history information is missing or not, and check if there is any loss.
If the operation history information is missing, a retransmission request including information about the missing period is transmitted to the terminal-side wireless communication unit.
A traffic signal control method, characterized in that when the operation history information included in the loss period transmitted from the terminal-side wireless communication unit is received, the operation history information is stored in the own device. A traffic signal control program for causing a computer to execute the traffic signal control method according to claim 4. The terminal control device in the traffic signal control system according to claim 1 .

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