METHOD FOR MANAGING RIGHT-OF-WAY AT AN INTERSECTION

Abstract

The invention relates to a method (100) for managing right-of-way at an intersection. The invention proposes to take into account unforeseen events that may occur at an intersection when a priority vehicle approaches and that could interrupt traffic flow. In particular, the invention proposes to control the activation of the traffic signal associated with the priority vehicle, taking into account the nature and impact of these unforeseen events. To this end, the invention proposes to modify the activation schedule of the intersection's traffic signals only if necessary.

Description

METHOD FOR MANAGING RIGHT-OF-WAY AT AN INTERSECTION Field of invention The invention relates to priority intervention in traffic signal control systems. In particular, it concerns a method for managing right-of-way at an intersection where one of the traffic lanes is designated for the passage of at least one public transport vehicle. Background The prior art from which the invention has been developed is described below. Patent FR2852724A1 provides a method for managing the priority of a public transport vehicle at a crossing. In this method, in a primary detection stage, the arrival of a public transport vehicle at a predetermined position located before reaching the intersection is detected. From that moment on, the traffic light associated with the public transport vehicle is turned on by means of an appropriate signal to allow it to pass. In practice, the crossing signage is modified so that first the passage of movements antagonistic to the circulation of the public transport vehicle is prohibited and then the passage of the same is allowed. This process allows for the precise definition of the predetermined position, from which the correct moment of illumination of the light signal associated with the public transport vehicle is derived, maintaining the regularity of its speed as much as possible. However, one of the disadvantages of this process is that it is carried out in a predefined and irreversible manner, even if an unexpected event interrupts the crossing of the intersection after the arrival of the public transport vehicle is detected. In this case, the phases of the ignition safety sequence and MA / traffic light shutdowns can be very long and cause time losses, as well as exasperation, for both users and public transport. These events are known to be frequent, originate from multiple sources, and occur at many intersections. Thus, this process can lead to the traffic light associated with the passage of the public transport vehicle turning on, when it cannot cross the intersection. Furthermore, public transport vehicles are no longer the only priority vehicles. However, the current method only considers public transport vehicles and does not take into account other priority vehicles such as police cars or ambulances. Summary of the invention The invention aims to mitigate these drawbacks. The invention relates, in particular, to a method for managing right-of-way at a first intersection where at least two opposing traffic movements meet or diverge, at least one of which is adapted for the passage of at least one public transport vehicle. Specifically, the first intersection includes a priority signal. According to the invention, the method comprises: - a stage of detecting the arrival of the public transport vehicle at a predetermined first position before the first intersection, in order to trigger a predetermined countdown, called the pre-ignition delay, during which the public transport vehicle approaches the priority signal; - a first stage of obtaining at least one environmental condition associated with the first intersection. - a comparison stage between the environmental condition and at least one predetermined comparison value, and - a stage of suspending the continuation of the priority management process according to the comparison stage, so that it returns to the first stage of obtaining after a predetermined update time. In a first embodiment of the invention, the predetermined comparison value is obtained from a rule-based expert system. In a second embodiment of the invention, the predetermined comparison value is obtained from a previously trained learning model. In a first embodiment, the suspension stage comprises the transmission of a driving assistance signal, SAC, associated with the priority signal. In an example of the first embodiment, the suspension stage further comprises a stage of changing a SAC blink frequency to a frequency, called the slow frequency, which is substantially lower than a predetermined fixed SAC frequency. In a second embodiment, the suspension stage further comprises a stage of decrementing a current value of the delay before ignition by a predetermined decrement value. In a third embodiment, the method also includes a stage of continuation of the priority management process according to the comparison stage. In an example of the third embodiment, the tracking stage comprises conducting the priority signal based on a current value of the delay before ignition. In a fourth embodiment, the method further comprises a second stage of obtaining at least one environmental condition associated with at least one second intersection different from the first intersection. In a fifth embodiment, the method is implemented by a system comprising a central remote control server and at least one crossing control unit disposed at the first intersection; the central remote control server is configured to generate the commands to be executed by the crossing control unit. MA / Brief description of the drawings Other features and advantages of the invention will be better understood from the following description and with reference to the accompanying drawings, which are illustrative and not limiting. Figure 1 shows a crossing. Figure 2 shows a method for managing right-of-way according to the invention. The figures do not necessarily respect the scale, especially in terms of thickness, and this is for illustrative purposes. Description Next, we describe a summary of the invention and the associated vocabulary, before presenting the disadvantages of the prior art and, finally, showing in more detail how the invention remedies them. The invention proposes to take into account unforeseen events that may occur at an intersection during the approach of a priority vehicle and that could disrupt the crossing. In particular, the invention proposes to control the activation signal of the traffic light associated with the priority vehicle, taking into account the nature and impact of these unforeseen events. To this end, the invention proposes to modify the activation sequence of the traffic lights at the intersection only if necessary. Thus, the invention relates to a method of managing right-of-way at a first intersection. An intersection is understood to be a place where at least two opposing traffic movements converge or conflict. Figure 1 shows a first intersection 10. In the example in Figure 1, the first intersection 10 comprises a first lane 11 with two directions of travel S1, S2 and a second lane 12 with one direction of travel S3. However, the first intersection 10 may comprise three, four or more traffic lanes, without it being necessary to substantially modify the invention. In the invention, the first intersection 10 comprises a priority signal that determines the right of way at the first intersection 10. In other words, it is the state of the priority signal that establishes the permission or prohibition of passage at the first intersection 10. Below, and without limitation, we describe different ways to implement priority signage. In one form, according to the regulations, the priority signage is illuminated and uses signs with one or more colored lights. In a second form, according to the regulations, priority signaling is mechanical and uses signals made by means of a cross or colored symbol. Returning to Figure 1, the first traffic lane 11 comprises two traffic lights 13 while the second traffic lane 12 comprises only one traffic light 14. As a reminder, it should be noted that the safety sequence for switching on and off a traffic light 13, 14 comprises a cyclical succession of phases, in which each phase authorizes certain movements and prohibits others for vehicles and other users of the first intersection 10. The duration of each phase is usually fixed. However, it can also vary, for example, depending on the traffic situation, to allow several intersections to be coordinated with each other, or to give priority to certain types of vehicles. Furthermore, legal provisions usually regulate this duration and require, for example, that the on-time of a traffic light not be less than six seconds, known as the minimum green time, and that the off-time of a traffic light not exceed 120 seconds.Finally, it should be noted that an inference, called "safety time", separates the different phases of the lighting and extinguishing safety sequence, to allow vehicles and users of the crossing to safely complete their ongoing movements before the next phase is activated. Below, and without limitation, we describe different examples of possible intersection layouts. In a first example, when the first intersection 10 comprises two one-way traffic lanes, the safety signage comprises at least two traffic lights, namely, one traffic light for each traffic lane. In a second example, when the first intersection 10 comprises more than two traffic lanes, the safety signaling includes more than two traffic lights. In this case, the number of traffic lights will depend on the layout of the first intersection 10 and, in particular, on the direction or directions of traffic. The following, and not as a limitation, describes different ways of controlling safety signage at the first intersection 10. In a first method of the invention, the safety signaling is controlled locally. In this case, the decision to control the safety signaling is made directly at the first intersection 10. In practice, devices called intersection control units are used to control the safety signaling. In a second embodiment of the invention, the safety signaling is controlled from a remote central control server. In this case, the safety signaling decision is made on a remote central control server. Under these conditions, the decision-making process can also take into account the safety signaling of other intersections located in the vicinity of the first intersection 10. In practice, the intersection control units are also used to control the safety signaling. However, in this configuration, it is the remote central control server that generates the commands to be executed by the intersection control units. In both cases, computer / electronic equipment of a known type is used. MA / In the invention, at least one of the opposing traffic movements is adapted for the passage of at least one public transport vehicle. Public transport vehicles are defined as public passenger transport systems. In practice, public transport vehicles typically have priority at traffic lights. Furthermore, public transport vehicles aim to reduce air pollution and greenhouse gas emissions, as well as combat urban congestion by helping to shift the modal share from private cars to public transport. The following are non-exhaustive examples of public transport vehicles. Trams and Bus Rapid Transit (BRT) vehicles are well-known examples of public transport vehicles. A tram is understood to be a permanently guided public transport vehicle, characterized by a railway vehicle (rail on rail) or a road vehicle (tire vehicle with, for example, a permanent guide device on rails), which runs mainly on urban roads and operates with visual guidance. ATR is a form of public transport characterized by a road vehicle that provides a higher level of continuous service than conventional bus lines (frequency, speed, regularity, comfort, accessibility) and approaches the performance of trams. It can be guided (physically or immaterially guided) or unguided, with internal combustion, electric, or hybrid engines. In one embodiment of the invention, all or part of the traffic lanes that are adapted for the passage of the collective transport vehicle are also adapted for the passage of at least one of the so-called public service vehicles. Below, we describe several examples of public service vehicles. In a first example, the public service vehicle may be a priority public service vehicle, such as police, gendarmerie, customs, fire and rescue service vehicles. In a second example, the public service vehicle may be a non-priority public service vehicle, but one that has right of way, such as an ambulance. In the invention, the other traffic lanes that are not suitable for the passage of the public transport vehicle are suitable for the passage of other types of vehicles or users, such as, for example, taxis, cars, trucks, cyclists, buses or pedestrians. In Figure 2, in a stage 110, method 100, according to the invention, comprises detecting the arrival of the public transport vehicle at a predetermined first position prior to the first intersection 10. To this end, the invention uses one or more detection devices of a known type, which are suitable for detecting public transport vehicles. These devices include one or more sensors, which can be either intrusive (e.g., inductive loop sensor, magnetometric sensor, fiber optic sensor) or non-intrusive (e.g., microwave sensor using the Doppler effect installed on the road shoulder, microwave sensor using two antennas installed high, oriented, or perpendicular to the roadway, laser sensor, active / passive infrared sensor, video sensor, active / passive acoustic sensor, GPS-type satellite location sensor, SAE operational support system). These devices can be used to detect whether or not a vehicle is in a traffic lane. Furthermore, these vehicle detection devices can also detect the type of vehicle in the traffic lane. In the example shown in Figure 1, the second traffic lane 12 comprises a first vehicle detection device 15, a second vehicle detection device 16, and a third vehicle detection device 17. The different detection devices are described in succession below. The first vehicle detection device 15 allows a public transport vehicle to be detected at a sufficient distance from the first intersection 10 to allow the traffic light 14 to be switched on in sufficient advance to respect all the safety limitations of the first intersection 10 and the kinematics of the public transport vehicle. For this purpose, the first vehicle detection device 15 is generally installed at a distance from the safety sign, calculated based on an assumption of the public transport vehicle's speed and braking capacity. For example, a first vehicle detection device 15 will be installed at a distance of approximately 180 m from the first intersection 10, assuming a speed of 10 m / s for the public transport vehicle. The second vehicle detection device 16 performs the same functions as the first vehicle detection device 15 and can be used to compensate for any malfunction of the latter. Finally, the third vehicle detection device 17 provides confirmation of the arrival of the public transport vehicle at traffic light 14. Returning to Figure 2, after the detection of the arrival of the public transport vehicle, a predetermined countdown is activated, known as the delay before ignition, during which the public transport vehicle approaches traffic light 14 of the first intersection 10. In particular, the delay before ignition corresponds to a theoretical time needed to turn on traffic light 14. Indeed, when the actual value of the delay before ignition is equal to zero, this authorizes the green ignition of traffic light 14 to allow the passage of the public transport vehicle through the first intersection 10. As is known, the delay before ignition is determined taking into account all the maximum limitations that must be respected at the first intersection 10, such as the minimum green times, safety times, the change times between traffic lights at the crossing, or even the sequence of the stages of prioritizing the public transport vehicle for its passage from the first intersection 10. Next, we present the disadvantages of the prior art that the invention attempts to remedy. In current traffic control systems, as long as no public transport vehicle is detected before reaching the intersection in question, only the traffic lights associated with the other users of the first intersection 10 are successively controlled, without turning on the traffic light 14 associated with the public transport vehicle. However, when a public transport vehicle is detected approaching the first intersection 10, an appropriate signal is used to turn on the traffic light 14 associated with the public transport vehicle to allow it to pass. One of the disadvantages of the previous technique is that it is carried out in a predefined and irreversible manner, even if an unexpected event interrupts the crossing after the arrival of a public transport vehicle is detected. In this case, the phases of the traffic light activation and deactivation sequence can be very long, causing delays and frustration for both road users and public transport operators. Below, we show in more detail how the invention remedies these drawbacks. Therefore, the invention proposes a mechanism that, after detecting the arrival of the public transport vehicle, allows the execution of the prior art method to be suspended when at least one unexpected event occurs that would interrupt the crossing of the first intersection 10, the so-called EIP (for its French acronym). As such, in a stage 120, method 100 comprises a first stage of obtaining at least one environmental condition associated with the first intersection 10. In this way, the occurrence of at least one EIP can be detected. The following, and not as a limitation, describes how to obtain an environmental condition associated with the first intersection 10 to detect the occurrence of an EIP. In particular, at least at the first intersection 10, one or more environmental parameter measuring sensors of a known type may be arranged, which are suitable for measuring physical, biological and / or chemical parameters. The following, and not as a limitation, describes different types of environmental parameter measurements that can be obtained at the first intersection 10 and / or in its surroundings. In a first embodiment, stage 120 comprises obtaining a measure of the state of railway and road signaling, for example, from the signaling circuits that operators and managers of public transport or mobility vehicles routinely use. In a second embodiment, step 120 comprises obtaining at least one traffic volume measurement, for example, from traffic data collection sensors commonly used by operators and managers of public transport or mobility vehicles. For example, one or more of the following intrusive road sensors (e.g., magnetic sensor, piezoelectric sensor, pneumatic tube sensor, strain gauge sensor, resistive sensor, fiber optic sensor) and non-intrusive road sensors (e.g., microwave sensor using the Doppler effect and installed on the road shoulder, microwave sensor using two antennas and installed high up, facing or perpendicular to the road, laser sensor, active / passive infrared sensor, video sensor, active / passive acoustic sensor) may be used. In a third embodiment, step 120 comprises obtaining at least one measurement of the ambient sound level, for example, from acoustic sensors. In a fourth embodiment, step 120 comprises obtaining at least one measurement of the pollution level, for example, from air quality sensors. MA / In a fifth embodiment, step 120 comprises detecting the arrival of a public service vehicle, for example, from vehicle detection devices such as those described above, as well as from specific equipment of a known type carried on board the public service vehicle. The following, and not as a limitation, describes how to obtain an environmental condition associated with a different intersection from the first intersection 10 to detect the occurrence of an EIP. In a particular embodiment of the invention, process 100 comprises a second step of obtaining at least one environmental condition associated with at least a second intersection different from the first intersection 10. In this case, one or more sensors for measuring environmental parameters of the same type as those mentioned above may be arranged at least at the second intersection. Thus, in the context of this particular embodiment, the safety signaling of the first intersection 10 is controlled from a central remote control server, and the decision-making process may take into account the environmental conditions occurring at other intersections located in the vicinity of the first intersection 10 that may impact the passage of the public transport vehicle at the first intersection 10. Next, we will continue to show how the invention remedies the disadvantages mentioned above. Returning to Figure 2, in a stage 130, process 100 comprises a comparison between at least one environmental condition and at least one predetermined comparison value. In a first implementation, the predetermined comparison value is obtained from a rule-based expert system, in which each environmental condition is associated with one or more rules. In this way, the experience of operators and managers of public transport or mobility vehicles can be used to derive the rules. In a second embodiment, the default comparison value is obtained from a pre-trained learning model. In this way, the large amount of digital data regularly generated by the sensors at the intersections can be used to train a learning model and derive the rules. At stage 140, depending on stage 130, process 100 involves suspending its continuation and returning to stage 120 after a predetermined update time. Thus, process 100 is understood to loop between stages 120 and 140 until the conditions for continuing process 100 are met. The following, and not as a limitation, describes how to determine whether to suspend the continuation of process 100 and return to stage 120. In a first example, the intention is to return to stage 120 when, in stage 130, the environmental condition is beyond the predetermined comparison value. In a second example, the intention is to return to stage 120 when, in stage 130, the environmental condition is below the predetermined comparison value. The following is a non-limiting example of the values ​​that the default update time can take. In one example, the default update time is less than or equal to five seconds, preferably less than or equal to one second. The following describes, in a non-exhaustive manner, what it means to suspend the continuation of process 100. In the invention, suspending the continuation of process 100 means suspending the delay before ignition. Furthermore, when process 100 is suspended, step 140 also includes a step of decrementing the current value of the delay before ignition by a predetermined decrement value. The following is a non-limiting example of the values ​​that the default decrement value can take. MA / remote control center for your right-of-way request. In practice, the flashing of the diamond at a predetermined fixed frequency (for example, half a second) informs the driver that their vehicle has been authorized to cross the intersection. In other words, the driver knows their vehicle has been authorized whenever the diamond flashes at this predetermined fixed frequency. Step 140 also includes controlling the modification of the SAC signal's flashing frequency to a frequency, the so-called slow frequency, which is substantially lower than the aforementioned predetermined fixed frequency. This informs the public transport vehicle driver of a possible delay in the signal's activation relative to their usual traffic signal timings at the intersection, allowing them to adjust their driving for greater comfort, smoothness, and safety. Thus, when the continuation of process 100 is suspended, the public transport vehicle continues to move, but the driver is informed of a possible delay in crossing the first intersection 10. The following is a non-limiting example of the values ​​that the slow frequency can take. In one example, the value of the slow frequency is one and a half seconds or more. The following describes, in a non-exhaustive manner, what it means to resume the continuation of process 100 after a suspension. In the invention, after a suspension, resuming the continuation of process 100 means restarting the countdown of the delay before ignition, from its current value, so that the signal to turn on can be sent to traffic light 14. As noted above, the current value of the delay before ignition may have changed upon detection of an EIP (Emergency Interruption Perception). In this case, if the current delay before activation does not allow the transit vehicle to pass the first intersection 10 in time, then the transit vehicle driver can be advised not to cross the first intersection 10 and to wait for the next safety activation / deactivation sequence. For example, the flashing frequency of the SAC signal can be modified (e.g., by substantially increasing its frequency or stopping the flashing) so that the transit vehicle driver does not pass through the first intersection 10. The following, and not as a limitation, describes what happens when process 100 is not suspended or ceases to be suspended. When process 100 is not suspended or ceases to be suspended, it continues in stage 150 during which the green light of traffic light 14 is ordered to be turned on so that the public transport vehicle crosses the first intersection 10. Preferably, the moment when the green window of traffic light 14 begins and the moment of the passage of the public transport vehicle over the line of traffic light 14 are recorded in memory. However, in a particular instance of stage 150, process 100 can be suspended again while the transit vehicle passes through the first intersection 10. In this case, the green light of traffic signal 14 can be controlled to be on or off according to a predefined strategy. Optionally, it can also be provided that method 100 returns to stage 120. Next, in stage 160, the mathematical magnitudes are calculated from the information stored in memory. Below, we describe how to calculate mathematical magnitudes in a non-limiting way. In a first implementation, the time between the start of the green window and the moment of the passage of the public transport vehicle in the line of the light signal is calculated. In a second embodiment, an induced delay in the travel time of the public transport vehicle is calculated from the current value of the induced delay counter. Thus, the process allows for the generation of three criteria that qualify the quality of the tram's priority and kinematics. The first criterion is the total duration of the suspension. The second criterion is the actual delay in the activation of the tram's lights, due to environmental conditions. And the third criterion is the tram's delay in the journey time. MA / t / ZUZZ / U4UZZU We have described and illustrated the invention. However, the invention is not limited to the embodiments we have presented. Thus, a person skilled in the art can deduce other variations and embodiments from the description and accompanying figures. The invention can be adapted to many different variations and applications than those described above. In particular, unless otherwise stated, the various structural and functional features of each of the embodiments described above should not be considered as combined, closely, or inextricably linked, but rather as mere juxtapositions. Furthermore, the structural and / or functional features of the various implementations described above may be subject, in whole or in part, to any different juxtaposition or combination.

Claims

Claims 1. A method (100) for managing right-of-way at a first intersection (10) where at least two opposing traffic movements meet or intersect, at least one of which is adapted for the passage of at least one priority public transport vehicle at the first intersection (10), the first intersection (10) comprising a priority signal (14), the method comprising - a detection stage (110), by means of a detection device external to the priority public transport vehicle and coupled to the roadway, of the arrival of the priority public transport vehicle at a predetermined first position before the first intersection (10), in order to trigger a predetermined countdown, called the pre-start delay,during which the priority public transport vehicle approaches the priority signal and when the green light of the traffic light (14) expires, the passage of the priority public transport vehicle through the first intersection (10) is authorized - a first stage of obtaining (120), by means of one or more sensors measuring environmental parameters, at least one environmental condition associated with the first intersection (10), followed by a stage of storing the environmental condition in a memory, - a stage of comparing (130), from the memory, between the environmental condition and at least one predetermined comparison value, followed by a stage of storing the result of the comparison in the memory and - a stage of suspending (140), from the memory, the continuation of the priority management process according to the comparison stage,so the delay countdown before power-up is suspended at a current value and returns to the first stage of acquisition (120) after a predetermined update time.

2. A method according to claim 1, wherein the suspension stage (140) comprises the operation of a driving assistance signal, SAO, associated with the priority signal, to provide the driver of the priority public transport vehicle with information on the status of the connection and disconnection sequence of the priority signal (14), and to indicate the consideration of the priority public transport vehicle to pass the first intersection (10).

3. A method according to claim 2, wherein the suspension step (140) further comprises a step for changing a SAC blink frequency to a frequency, called the slow frequency, which is substantially lower than a predetermined fixed SAC frequency.

4. A method according to any of claims 1 to 3, wherein the suspension step (140) further comprises a step of decrementing an actual value of the delay before ignition by a predetermined decrement value.

5. The method according to any one of claims 1 to 4 further comprises a step of continuing (150) the priority management process according to the comparison step.

6. A method according to claim 5, wherein the tracking step (150) comprises driving the priority signaling from a current value of the delay before ignition.

7. A method according to any of claims 1 to 5, wherein the predetermined comparison value is obtained from a rule-based expert system.

8. A method according to any of claims 1 to 5, wherein the predetermined comparison value is obtained from a previously trained learning model.

9. A method according to any one of claims 1 to 8, further comprising a second stage of obtaining, by means of one or more environmental parameter measuring sensors, at least one environmental condition associated with at least a second intersection different from the first intersection (10).

10. A method according to any one of claims 1 to 9, wherein the method is implemented by a system comprising a central remote control server and at least one intersection control unit disposed at the first intersection (10), the central remote control server being configured to generate the commands to be executed by the intersection control unit.

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