FR3111226A1 - Method and system of road traffic control at a traffic light intersection - Google Patents

Abstract

The invention relates to a method and system for controlling road traffic at an intersection comprising a first set of traffic lights (101, 102) for controlling the traffic of a second set of vehicles (11 to 13). For this purpose, a peripheral computing device (1002) receives location information from each vehicle (11 to 13) in communication with a cell of a wireless network associated with the peripheral computing device (1002). A state change command of a traffic light (101) of the first set is determined from the location information. This change of state command allows, for example, the traffic light controller (1003) to control each traffic light (101, 102) at the intersection. Figure for the abstract: Figure 1

Description

Method and system for controlling road traffic at a traffic light intersection

The invention relates to methods and devices for controlling road traffic at a traffic light intersection.

Technology background

In order to regulate road traffic, in particular in urban areas, it is known to set up traffic lights, also called traffic lights. These traffic lights make it possible to organize the traffic, in particular at the level of the intersections which are equipped with them.

A traffic light switches from one state to another to authorize or prohibit the passage of vehicles. At certain intersections with traffic lights, the transition from one state to another is triggered when the presence of vehicles is detected. Presence detection is obtained for example by an inductive loop inserted into the roadway, the presence of a vehicle being detected by this loop when the vehicle is positioned above the loop. Once the vehicle has been detected, the traffic light changes state to, for example, authorize the passage of the vehicle.

However, the detection of the presence of a vehicle by inductive loop is not perfect since the vehicle must be well positioned above the loop. If the vehicle is not far enough ahead at the intersection, it is not detected by the loop and the light does not turn green, the vehicle(s) waiting at this light then being blocked, causing inconvenience for the driver(s). vehicles waiting for the change of state of the light to be able to pass.

An object of the present invention is to improve the management of traffic lights in a road environment, for example at a crossroads.

Another object of the present invention is to optimize the regulation of road traffic at a traffic light intersection.

According to a first aspect, the invention relates to a method of controlling road traffic at a traffic light intersection in a road environment, a first set of traffic lights regulating the passage of a second set of vehicles at the intersection, the first set of traffic lights being controlled by a traffic light controller associated with a peripheral computing device, the peripheral computing device being associated with at least one cell of a cellular wireless network, the method comprising the following steps implemented by a system comprising the peripheral computing device and the traffic light controller:

- Receiving location information from each vehicle of the second set in communication with the at least one cell;

- determination of a command to change the state of a traffic light of the first set according to the location information;

- control of the first set of traffic lights according to the traffic light state change command.

According to a variant, the state change command is a function of a number of vehicles approaching the traffic light.

According to an additional variant, the command to change state corresponds to a command to switch from a state representative of prohibition of passage, called a red light, to a state representative of authorization to pass, called a green light, when a number of vehicles above a threshold is located when stopped at the level of the traffic light of the first set, the control of the other lights of the first set being a function of the change of state command.

According to yet another variant, further comprising the following steps:

- reception of road mapping information of the road environment;

- estimation of at least one traffic flow of the second set of vehicles in the road environment according to the mapping information and the location information received for different time instants;

- determination of the state change command from an estimation result.

According to an additional variant, the state change command comprises a sequence of consecutive state changes of the traffic light, each state of the sequence being associated with a duration during which the traffic light remains in each state.

According to yet another variant, the peripheral computing device comprises the traffic light controller.

According to a second aspect, the invention relates to a system comprising a peripheral computing device and a traffic light controller, the system being configured for the implementation of the steps of the method as described above according to the first aspect of the invention.

Alternatively, the system further comprises a set of traffic lights.

According to another variant, the system further comprises a set of vehicles.

According to a third aspect, the invention relates to a computer program which comprises instructions adapted for the execution of the steps of the method according to the first aspect of the invention, this in particular when the computer program is executed by at least one processor.

Such a computer program can use any programming language, and be in the form of source code, object code, or intermediate code between source code and object code, such as in a partially compiled form, or in any other desirable form.

According to a fourth aspect, the invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for the execution of the steps of the method according to the first aspect of the invention.

On the one hand, the recording medium can be any entity or device capable of storing the program. For example, the medium may comprise a storage means, such as a ROM memory, a CD-ROM or a ROM memory of the microelectronic circuit type, or even a magnetic recording means or a hard disk.

On the other hand, this recording medium can also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or hertzian radio or by self-directed laser beam or by other ways. The computer program according to the invention can in particular be downloaded from an Internet-type network.

Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to execute or to be used in the execution of the method in question.

Brief description of figures

Other characteristics and advantages of the invention will emerge from the description of the non-limiting embodiments of the invention below, with reference to the appended figures 1 to 3, in which:

schematically illustrates a road environment comprising an intersection with traffic lights, according to a particular embodiment of the present invention;

schematically illustrates a device of a system configured to control road traffic at the crossroads of FIG. 1, according to a particular embodiment of the present invention;

illustrates a flowchart of the different steps of a road traffic control method at the crossroads of FIG. 1, according to a particular embodiment of the present invention.

A method and system for controlling road traffic at a traffic light intersection in a road environment will now be described in the following with reference in conjunction to Figures 1 to 3.

According to a particular and non-limiting embodiment of the invention, a road traffic control method at an intersection comprising a first set of traffic lights makes it possible to regulate the traffic of a second set of vehicles. The method includes receiving, for example by a peripheral computing device, location information of each vehicle of the second set in communication with a cell of a wireless network associated with the peripheral computing device. A command to change the state of a traffic light of the first set is determined, for example by the peripheral computing device, from the location information. This state change command allows, for example, the traffic light controller to control each traffic light of the first set at the crossroads.

The use of vehicle location information located in a locally managed area by a peripheral computing device makes it possible to optimize traffic flows at a traffic light intersection by following the vehicle or vehicles arriving at a traffic light traffic light and by controlling this traffic light appropriately according to the flow of vehicles at the level of the light or approaching this light.

Local management, that is to say at the level of a peripheral computer device, which controls one or more cells of a wireless network, also makes it possible to ensure a certain level of data confidentiality, since the data are managed locally without being uploaded to a central server controlling the wireless network.

schematically illustrates a road environment comprising an intersection with traffic lights, according to a particular and non-limiting embodiment of the present invention.

Figure 1 illustrates a road junction with the intersection of traffic lanes 1100 and 1200. According to the figure, only part of the junction is illustrated for clarity. Traffic at this crossroads is controlled by a first set of traffic lights, namely a first traffic light 101 controlling the passage of vehicles 11, 12 at the crossroads, and a second traffic light 102 controlling the passage of a vehicle 13 at the crossroads.

The shape of the road intersection is arbitrary and the number of branches or traffic lanes that intersect at this intersection is arbitrary, for example equal to 2, 3, 4, 5, 6 or more lanes.

The priority of passage at the road junction for each vehicle of a second set of vehicles 11 to 13 is controlled by the first set of traffic lights, the number of traffic lights depending on the number of branches or traffic lanes crossing at the junction road.

FIG. 1 thus illustrates a road junction with two branches or traffic lanes 1100, 1200 with two traffic lights 101, 102 to control the passage of three vehicles 11 to 13. Of course, the number of branches, traffic lights and of vehicles illustrated in Figure 1 is purely illustrative and not limiting.

The traffic lights 101, 102 correspond for example to tricolor traffic lights with three states, for example a first state, called green light, where passage at the crossroads is authorized (vehicles can pass the traffic light when the light is at the second state) ; a second state, called red light, where passage at the crossroads is prohibited (vehicles must stop at the traffic light when the light is at the second state); and a third intermediate state between the first state and the second state, called orange light, which signals the transition from the first state to the second state.

The states taken by each traffic light are for example defined in the Vienna Convention on road signs. The number of states caught in the fire is not limited to three but can extend to four or two, depending on the country.

The transition from one state to another for each traffic light 101, 102 of the first set is advantageously controlled by a device 1003 called a traffic light controller. A traffic light controller corresponds to an automaton adapted to the management of traffic lights in traffic control. The traffic light controller is configured to manage each traffic light of the intersection according to a set of rules determined by respecting safety constraints for branches or antagonistic traffic lanes, the transition from one state to another for a traffic light 101 being coordinated with the passage from one state to another for one or more other lights 102 of the same intersection according to priority rules preventing vehicles traveling on branches with intersection between them passing at the same time at the intersection, to avoid collisions between for example the vehicles 11, 12 on the one hand and the vehicle 13 on the other hand. For example, the rules provide that when the first traffic light 101 changes from the first state to the second state (via the third state), the second traffic light 102 changes from the second state to the first state, with a safety delay for example to prevent a vehicle from traffic lane 1100 from entering the intersection at the same time as a vehicle from traffic lane 1200.

According to a variant, the traffic light controller 1003 controls traffic lights at different road intersections, with optional coordination between the lights at different road intersections, for example to create a green wave on the same traffic axis.

The traffic light controller 1003 is for example connected to each traffic light 101, 102 of the first set via a wired link, to transmit the instructions or command to change state to each light, in a synchronized manner. According to a variant, all or part of the traffic lights 101, 102 are connected to the traffic light controller 1003 via a wireless link.

The traffic light controller 1003 is advantageously associated with a peripheral computing device 1002. The peripheral computing device 1002 is for example connected to the traffic light controller 1003 via a wired link, for example an Ethernet or fiber optic link, or via a wireless link, for example of the Wifi® type. The peripheral computer device 1002 is itself associated with an antenna (or base station) 1001 of a communication network.

The communication network advantageously corresponds to a cellular type network, for example a cellular mobile telephone network. Such a cellular network is composed of cells, each cell corresponding to a geographical coverage area of a communication antenna (also called base station) making it possible to establish radio communications between users (also called clients or users, each user being carrier of a mobile communication device) and/or between the users and the network infrastructure of the network 1. The size of a cell varies and is for example between 1 km and a few tens of kilometers (for example 20 or 30 kms).

Thus, a geographical coverage area or a cell is associated with the peripheral computing device 1002 through the antenna 1001 associated with it. According to a variant embodiment, several antennas (and therefore several cells) are associated with the same peripheral computing device 101.

Of course, the number of peripheral computing devices of the communication network is not limited to 1 but extends to any number with, for each peripheral computing device, one or more antennas or cells of the network associated with it.

The wireless cellular communication network implements for example communications according to LTE technology (from English "Long-Term Evolution" or in French "Evolution à long terme"), LTE-Advanced (from English "Long -Term Evolution - Advanced" or in French "Evolution in the long term advanced"), C-V2X (from the English "Cellular - Vehicle to Everything" or in French "Cellular - Vehicle to everything") which is based on the 4G and soon 5G, based on LTE.

A user corresponds, for example, to a natural person wearing a mobile communication device of the smart phone type (from the English “smartphone”) or a tablet. According to a variant, a user corresponds to a vehicle of the second set of vehicles 11 to 13 carrying a communication device of the computer type, for example a telematics control unit, called TCU (from the English "Telematic Control Unit"), or a mobile communication device of the smart phone type on board the vehicle and connected to the latter via a wired connection (for example of the USB type (from the English “Universal Serial Bus” or in French “Universal Serial Bus”)) or without wire (for example of the Bluetooth® or Wifi® type).

A peripheral computing device advantageously corresponds to a device of the MEC type (from the English “Mobile Edge Computing” or “Multi-Access Edge Computing”) which makes it possible to move the computing traffic and the services from a “cloud” 100 (or “ cloud” in French) centralized to an edge network, closer to users or client devices. Instead of sending any data to be processed in the "cloud" 100, an edge network analyzes, processes and/or stores the data. Collecting and processing data close to users reduces communication latency and increases the bandwidth available to each user by avoiding the bottleneck effect when all data is redirected to the "cloud" or emitted from the “cloud” 100. The standards governing the operation of the architecture and of the MEC-compatible devices are defined by ETSI (from the English “European Telecommunications Standards Institute” or in French “Institut européen des norms de Télécommunication”).

The peripheral computer device 1001 is connected to the infrastructure of the “cloud” 100 (for example to servers of the “cloud” 100) via a wired backbone type link, for example of the Ethernet type or fiber optic.

According to the example of Figure 1, the vehicles 11, 12 and 13 are associated with the antenna 1001, that is to say that the communications transmitted and received by these vehicles 11 to 13 are relayed via the antenna 1010 .

A road traffic control process at a road intersection will now be described based on the example of FIG. 1. The process is advantageously implemented by a system comprising the MEC device 1002 and the traffic light controller 1003. According to Alternatively, the MEC 1002 device and the traffic light controller form a single device.

In a first operation, the system, for example the MEC device 1002, receives location information from each vehicle 11 to 13 of the second set of vehicles. This location information is for example obtained for each vehicle 11 to 13 from an on-board satellite positioning system receiver, the information corresponding for example to location data of the GPS type (from the English “Global Positioning System” or in French “Global Positioning System”) obtained by each vehicle 11 to 13.

The information is for example transmitted by each vehicle to the device MEC 1002 at regular intervals, for example every 1, 5, 10, 60 seconds.

Alternatively, location information received by MEC device 1002 is obtained from each vehicle in communication with the cell(s) of the cellular network associated with MEC device 1002.

According to another variant, the system also receives from each vehicle representative vehicle identification information, corresponding for example to a vehicle identification number, called VIN (from the English "Vehicle Identification Number", corresponding to the vehicle series). This information is for example included in a data frame header transmitted by any vehicle in the network via the antenna with which it is associated, each VIN code is unique and associated with a single vehicle, this code being made up of 17 alphanumeric characters .

With such identification information, the MEC 1002 device is able to follow the movement over time of each vehicle in communication with the network cell(s) associated with it.

In a second operation, the system, for example the MEC device 1002, determines one or more state change commands for one or more of the traffic lights 101, 102 of the first set of lights according to the location information of the vehicles 11 to 13 received in the first operation.

According to a particular embodiment, the MEC device 1002 determines the number of vehicles 11, 12 stopped at the level of the traffic light 101, the light 101 being in the second state, called a red light prohibiting the passage of vehicles in the road junction. The traffic light 101 is for example positioned on a traffic lane 1001 little used, the light 101 being by default in the second state, called red light, while the traffic light 102 is positioned on a so-called main axis 1002 where the traffic light 102 is by default in the first state, said green light authorizing vehicles including vehicle 13 to pass through the crossroads.

According to this example, the MEC device 1002 determines the number of vehicles located at the level of the traffic light 101 and compares this number with a threshold value, for example equal to 1, 2, 3 or more. When the number of vehicles 11, 12 located at the traffic light 101 reaches the threshold, the MEC device 1002 determines and generates a first state change command for the traffic light 101 so that the latter changes from the second state, called traffic light red, in the first state, says green light to authorize the passage of vehicles 11, 12 when stopped at this light 101.

This first state change command is for example transmitted to the traffic light controller 1003.

According to a variant, the MEC device 1002 determines the duration during which one or more of the vehicles 11, 12 is stationary at the traffic light 101. The duration is for example determined by analyzing the successive positions received for each vehicle 11, 12 over time. When the time during which the vehicle(s) 11, 12 is stationary at the traffic light 101 reaches a determined threshold (for example 20, 30, 60, 120 seconds) then the MEC device 1002 generates the first change command of 'state.

According to yet another variant, the MEC 1002 device generates the first command when the number of vehicles located at the traffic light 101 reaches a first threshold (for example equal to 3 or 5 vehicles) and the MEC 1002 device generates the first command when the number of vehicles located at the level of the traffic light 101 is lower than this first threshold and that the duration during which the vehicles are stationary at the level of the traffic light reaches the determined threshold value (for example 20, 30, 60, 120 seconds).

In a third operation, the traffic light controller 1003 controls the first set of traffic lights according to the first command determined by the MEC device 1002 at the second operation. The traffic light controller 1003 triggers, for example by the transmission of control signals or instructions, the change of state of the traffic light 101 so that the latter passes from the second state to the first state and triggers in parallel the changes of states of the other traffic lights at the crossroads depending on the change in the state of traffic light 101 and the rules ensuring safety at the crossroads. For example, the traffic light controller 1003 triggers in a synchronized manner the change of state of the traffic light 102 so that the latter passes from the first state to the second state to block the passage through the crossroads of the vehicle 13 arriving at the traffic light 102, to avoid any collision between the vehicles 11, 12 on the one hand and the vehicle 13 on the other hand.

According to another example, the MEC device 1002 determines all the commands for changing the state of each of the lights 101, 102 of the intersection at the second operation and transmits them to the traffic light controller 1003 which causes them to be applied by each of the lights 101, 102 of the crossroads during the third operation.

According to another particular embodiment, the device MEC 1002 analyzes the movements of all the vehicles of the second set in communication with the cell or cells of the cellular network which are associated with it. The displacement of a vehicle corresponds to the set of positions taken by this vehicle as a function of time. The MEC 1002 device links these movements with mapping information of the road environment covered by the cell(s) associated with the MEC 1002 device, this mapping information being for example received from a “cloud” server 100 or stored in the memory of the MEC 1002 device. The linking of vehicle movement information with the mapping information allows the MEC 1002 device to estimate or determine one or more traffic flow hypotheses in the road environment comprising the road intersection controlled by the lights 101, 102. The analysis of the estimated traffic flow(s) allows the MEC device 102 to anticipate the times when one or more of these vehicles will arrive at the road junction. From the estimation of this or these traffic flows, the MEC device 1002 determines one or more state change commands for a traffic light 101 or for each traffic light 101, 102 of the intersection, with the aim of smooth traffic at the crossroads by avoiding excessively long waiting times at each traffic light 101, 102.

According to a variant, the state change command(s) comprise a sequence of state changes (for example a sequence comprising one or more cycles comprising first state then passage to the second state then passage to the third state), with a determined duration during which a fire is maintained in a determined state. The duration of each of the states is determined so as to make traffic more fluid in the intersection according to each traffic lane 1100, 1200 by minimizing the waiting time at each traffic light 101, 102, taking into account the traffic flow hypotheses circulation determined by the MEC 1002 device.

For example, the first traffic light 101 is controlled according to the following sequence: second state for 2 minutes then change to the first state for a duration of 20 seconds and so on; and the second traffic light 102 is controlled according to the following sequence: second state for a period of 20 seconds then passage to the first state for a period of 2 minutes (after brief passage to the third state) and so on. According to this example, priority is given to vehicles traveling on lane 1200 by leaving traffic light 102 green for a longer period than for traffic light 101, the number of vehicles traveling on the axis comprising or emerging on lane 1100 being less than the number of vehicles circulating on the axis including or leading to the 1200 lane.

Such a process makes it possible to optimize, to minimize waiting times and/or to make road traffic more fluid at an intersection by taking into account the position of vehicles arriving at or positioned at the level of the traffic lights controlling the passage. at this crossroads. Taking into account the movements of vehicles arriving at the intersection with a determined deadline (for example from 1 to several minutes) also makes it possible to anticipate possible congestion at the level of the lights by controlling the changes in status of each light on a determined time period rather than on an ad hoc basis when the change of state of a traffic light is generated once it is found that a number of vehicles are stationary at this traffic light.

schematically illustrates a device 2 of a system configured to control road traffic at a traffic light intersection in a road environment, according to a particular and non-limiting embodiment of the present invention. The device 2 corresponds for example to a computer peripheral device, called MEC device 1002, to a traffic light controller 1003 or to a device combining the MEC device 1002 and the traffic light controller 1003.

The device 2 is for example configured for the implementation of the operations described with regard to FIG. 1 and/or the steps of the method described with regard to FIG. 3. Examples of such a device 2 comprise, without being limited thereto , electronic equipment such as a computer or server, peripheral computing device or PLC. The elements of device 2, individually or in combination, can be integrated in a single integrated circuit, in several integrated circuits, and/or in discrete components. The device 2 can be made in the form of electronic circuits or software (or computer) modules or else a combination of electronic circuits and software modules. According to different particular embodiments, the device 2 is coupled in communication with other similar devices or systems, for example via a communication bus or through dedicated input/output ports.

The device 2 comprises one (or more) processor(s) 20 configured to execute instructions for carrying out the steps of the method and/or for executing the instructions of the software or software embedded in the device 2. The processor 20 can include integrated memory, an input/output interface, and various circuits known to those skilled in the art. The device 2 further comprises at least one memory 21 corresponding for example to a volatile and/or non-volatile memory and/or comprises a memory storage device which can comprise volatile and/or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic or optical disk.

The computer code of the on-board software or software comprising the instructions to be loaded and executed by the processor is for example stored on the memory 21.

According to a particular and non-limiting embodiment, the device 2 comprises a block 22 of interface elements for communicating with external devices, for example a remote server or the "cloud", other MEC devices, in-vehicle communications. The interface elements of block 22 include, for example, one or more RF radio frequency interfaces, for example of the Bluetooth® or Wi-Fi®, LTE type (from the English “Long-Term Evolution” or in French “Evolution à long terme “), LTE-Advanced (or in French LTE-advanced), 5G.

According to another particular embodiment, the device 2 comprises a communication interface 23 which makes it possible to establish communication with other devices (such as "cloud" servers 100, an MEC device, a traffic light controller) via a communication channel 230. The communication interface 23 corresponds for example to a transmitter configured to transmit and receive information and/or data via the communication channel 230. The communication interface 23 corresponds for example to a wired network Ethernet or fiber optic type.

According to an additional particular embodiment, the device 2 can supply output signals to one or more external devices, such as a display screen, one or more loudspeakers and/or other peripherals respectively via interfaces output not shown.

illustrates a flowchart of the different steps of a road traffic control method at a traffic light intersection in a road environment. The method is for example implemented by a system comprising the MEC device 1002 connected to the traffic light controller 1003 or by the device 2 of figure 2.

In a first step 31, location information for each vehicle of a second set of vehicles in communication with one or more cells of a wireless cellular network associated with the MEC device is received.

In a second step 32, a command to change the state of a traffic light of a first set of traffic lights regulating the passage of vehicles at the crossroads is determined according to the location information received in step 31.

In a third step 33, the first set of traffic lights is controlled according to the traffic light state change command determined in step 32.

Of course, the invention is not limited to the embodiments described above but extends to a method for controlling road traffic at a road junction, and to the device or system configured for the implementation of the method. The invention also relates to a method for determining commands for change(s) of state of one or more traffic lights of a road intersection, and to the device or system configured for the implementation of the method.

The invention also relates to a system comprising an MEC device, a traffic light controller connected to the MEC device and the first set of traffic lights and/or the second set of vehicles.

Claims (10)

A method of controlling road traffic at a traffic light intersection in a road environment, a first set of traffic lights (101, 102) regulating the passage of a second set of vehicles (11, 12, 13) at said intersection, said first set of traffic lights (101, 102) being controlled by a traffic light controller (1003) associated with a peripheral computing device (1002), said peripheral computing device being associated with at least one cell of a wireless cellular network , said method comprising the following steps implemented by a system comprising the peripheral computing device (1002) and the traffic light controller (1003):
- reception (31) of location information for each vehicle (11 to 13) of said second set in communication with said at least one cell;
- determination (32) of a command to change the state of a traffic light (101) of said first set according to said location information;
- control (33) of said first set of traffic lights (101, 102) according to said command to change the state of said traffic light (101). A method according to claim 1, wherein said state change command is a function of a number of vehicles approaching said traffic light (101). Method according to claim 1 or 2, for which the said command to change state corresponds to a command to pass from a state representative of prohibition of passage, called red light, to a state representative of authorization of passage, called traffic light. green, when a number of vehicles greater than a threshold is located stopped at said traffic light (101) of said first set, the control of the other lights (102) of said first set being a function of said change command 'state. Method according to one of claims 1 to 3, further comprising the following steps:
- receiving road mapping information from said road environment;
- estimation of at least one traffic flow of said second set of vehicles in said road environment based on said mapping information and said location information received for different time instants;
- determination of said state change command from a result of said estimation. A method according to claim 4, wherein said state change command comprises a sequence of consecutive state changes of said traffic light (101), each state of said sequence being associated with a time during which said traffic light (101 ) remains in said every state. Method according to one of claims 1 to 5, for which said peripheral computing device (1002) comprises said traffic light controller (1003). A system comprising a peripheral computing device (1002) and a traffic light controller (1003), said system being configured to implement the steps of the method according to any one of claims 1 to 6. A system according to claim 7 further comprising a set of traffic lights (101, 102). A system according to claim 7 or 8 further comprising a set of vehicles (11 to 13). Computer program product comprising instructions adapted for the execution of the steps of the method according to one of Claims 1 to 6, when the computer program is executed by at least one processor.