A method and system for controlling traffic lights

Abstract

This application discloses a traffic light control method and system. The method includes: acquiring pedestrian data, non-motorized vehicle data, motorized vehicle data, green light phase time data of the traffic lights, and motorized vehicle data of the non-traffic directions at the intersection, respectively; determining whether a phase switch is needed for the traffic lights in the corresponding traffic directions; in response to the need for a phase switch, immediately switching the green light phase of the traffic lights in the corresponding traffic directions to a yellow light phase or switching to a yellow light phase after the corresponding remaining time; in response to the lack of a phase switch, delaying the green light phase of the traffic lights in the corresponding traffic directions. Using the solution of this application, a traffic light control strategy that meets actual needs can be matched in real time according to traffic conditions, and the probability of traffic accidents can be reduced.

Description

Technical Field

[0001] This application generally relates to the field of traffic light control technology. More specifically, this application relates to a traffic light control method and system. Background Technology

[0002] With the acceleration of urbanization, problems such as traffic congestion and frequent accidents have become increasingly prominent, bringing unprecedented pressure to urban traffic management.

[0003] In existing technologies, traffic management is mainly carried out using fixed-time traffic signal control systems. However, fixed-time traffic signal control systems often struggle to adapt to dynamically changing traffic flow, especially during peak hours or when there is a sudden surge in pedestrian traffic due to special events, which can easily lead to safety hazards and traffic chaos.

[0004] In view of this, there is an urgent need to provide a traffic light control scheme to dynamically adjust traffic light timing, improve the safety and efficiency of pedestrians crossing the street, and at the same time ensure smooth vehicle traffic and reduce traffic chaos. Summary of the Invention

[0005] In order to at least solve one or more of the technical problems mentioned above, this application proposes a traffic light control scheme in several aspects.

[0006] In a first aspect, this application provides a traffic light control method, comprising: acquiring pedestrian data, non-motorized vehicle data, motorized vehicle data, green light phase time data of the traffic light, and motorized vehicle data of the non-traffic direction corresponding to the intersection, respectively. The pedestrian data includes pedestrian flow, pedestrian speed, and pedestrian position; the non-motorized vehicle data includes non-motorized vehicle flow, non-motorized vehicle speed, and non-motorized vehicle position; the green light phase time data includes the green light phase duration and the currently set total time; and the motorized vehicle data includes motorized vehicle flow, motorized vehicle speed, and motorized vehicle position. Based on the acquired pedestrian, non-motorized vehicle, and motorized vehicle data for the corresponding traffic direction at the intersection, determine whether a phase switch is needed for the traffic lights in that direction. If a phase switch is needed, immediately switch the green phase of the traffic lights in that direction to a yellow phase or switch the green phase to a yellow phase after the corresponding remaining time. If a phase switch is not needed, delay the green phase of the traffic lights in that direction based on all acquired data.

[0007] In some embodiments, in response to the need to switch the phase of the traffic lights in the corresponding direction of traffic at the intersection, a determination is made based on the acquired pedestrian data, non-motorized vehicle data, motorized vehicle data in the corresponding direction of traffic at the intersection and motorized vehicle data in the non-traffic direction corresponding to the intersection, as well as the traffic lights in the non-traffic direction corresponding to the intersection, as to whether it is necessary to immediately switch the phase of the traffic lights in the corresponding direction of traffic at the intersection; in response to the need to immediately switch the phase of the traffic lights in the corresponding direction of traffic at the intersection, the green phase of the traffic lights in the corresponding direction of traffic at the intersection is immediately switched to the yellow phase.

[0008] In some embodiments, in response to the lack of immediate phase switching of the traffic lights for the corresponding traffic direction at the intersection, a determination is made based on all acquired data as to whether a delay is needed after phase switching of the traffic lights for the corresponding traffic direction at the intersection; in response to the lack of need for a delay after phase switching of the traffic lights for the corresponding traffic direction at the intersection, the green phase of the traffic lights for the corresponding traffic direction at the intersection is switched to a yellow phase after its corresponding remaining time; in response to the need for a delay after phase switching of the traffic lights for the corresponding traffic direction at the intersection, the green phase of the traffic lights for the corresponding traffic direction at the intersection is switched to a yellow phase after its corresponding remaining time, and the yellow phase is delayed.

[0009] In some embodiments, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a second flow threshold, it is determined that the traffic lights in the corresponding direction of traffic at the intersection need to be switched in phase.

[0010] In some embodiments, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a third flow threshold, the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a fourth flow threshold, and the motorized vehicle flow in the non-traffic direction of the intersection is greater than the motorized vehicle flow in the corresponding direction of traffic at the intersection, it is determined that the phase of the traffic light in the corresponding direction of traffic at the intersection needs to be switched immediately; wherein, the third flow threshold is less than the first flow threshold, and the fourth flow threshold is less than the second flow threshold.

[0011] In some embodiments, the time required for the current last target to pass is obtained based on the pedestrian speed, pedestrian position, non-motorized vehicle speed, and non-motorized vehicle position in the corresponding traffic direction at the intersection, wherein the target is a pedestrian or a non-motorized vehicle; it is determined whether the time required for the current last target to pass is greater than the remaining time of the green light phase of the traffic light; if the time required for the current last target to pass is not greater than the remaining time of the green light phase of the traffic light, it is determined that no delay is needed after the phase switch of the traffic light in the corresponding traffic direction at the intersection; if the time required for the current last target to pass is greater than the remaining time of the green light phase of the traffic light, it is determined that a delay is needed after the phase switch of the traffic light in the corresponding traffic direction at the intersection.

[0012] In some embodiments, the difference between the time required for the last target to pass and the remaining time of the green phase of the traffic light is used as a first difference; the difference between the set waiting tolerance time and the duration of the green phase is used as a second difference; it is determined whether the first difference is less than the second difference; in response to the first difference being less than the second difference, the first difference is used as the delay time after the green phase of the traffic light in the corresponding direction of traffic at the intersection switches to the yellow phase; in response to the first difference being not less than the second difference, the second difference is used as the delay time after the green phase of the traffic light in the corresponding direction of traffic at the intersection switches to the yellow phase.

[0013] In some embodiments, delaying the green light phase of the traffic light in the corresponding direction of traffic at the intersection based on all acquired data includes: when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than a second flow threshold, obtaining the delay time of the green light phase according to a first delay time calculation formula, wherein the first delay time calculation formula is: Among them, T m T is the time required, calculated from the vehicle traffic data for the corresponding direction of traffic at the intersection, to reduce the vehicle traffic flow in that direction to equal the second traffic flow threshold. th The set waiting tolerance time; when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of the intersection is greater than the first flow threshold, and the motorized vehicle flow in the corresponding direction of the intersection is less than or equal to the second flow threshold, the delay time of the green light phase is obtained according to the second delay time calculation formula, where the second delay time calculation formula is: Among them, T n T is the time required, calculated using pedestrian and non-motorized vehicle data for the corresponding traffic directions at the intersection, to reduce the sum of pedestrian and non-motorized vehicle traffic flows in the corresponding traffic directions at the intersection to equal a first traffic flow threshold. th The set waiting time.

[0014] In some embodiments, delaying the green phase of the traffic lights for the corresponding traffic direction at the intersection based on all the acquired data further includes:

[0015] When the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than or equal to the first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the second flow threshold, the delay time of the green light phase is obtained according to the third delay time calculation formula, whereby the third delay time calculation formula is: Among them, T n T is the time required, calculated using pedestrian and non-motorized vehicle data for the corresponding traffic directions at the intersection, to reduce the sum of pedestrian and non-motorized vehicle traffic flows in the corresponding traffic directions at the intersection to equal a first traffic flow threshold. m T is the time required, calculated from the vehicle traffic data for the corresponding direction of traffic at the intersection, to reduce the vehicle traffic flow in that direction to equal the second traffic flow threshold. th ω is the set waiting patience time. n For T n The corresponding weight, ω m For T m The corresponding weights.

[0016] In a second aspect, this application provides a traffic light control system, which uses the traffic light control method described in any embodiment of the first aspect to control the traffic lights. The system includes: a data acquisition module, used to acquire pedestrian data, non-motorized vehicle data, motorized vehicle data, green light phase time data of the traffic lights, and motorized vehicle data of the non-traffic directions corresponding to the intersection, respectively; a judgment module, used to determine whether it is necessary to switch the phase of the traffic lights in the corresponding traffic directions of the intersection based on the acquired pedestrian data, non-motorized vehicle data, and motorized vehicle data; and an execution module, used to, in response to the need to switch the phase of the traffic lights in the corresponding traffic directions of the intersection, immediately switch the green light phase of the traffic lights in the corresponding traffic directions of the intersection to a yellow light phase or switch the green light phase of the traffic lights in the corresponding traffic directions of the intersection to a yellow light phase after its corresponding remaining time; and in response to the need not to switch the phase of the traffic lights in the corresponding traffic directions of the intersection, delay the green light phase of the traffic lights in the corresponding traffic directions of the intersection based on all the acquired data.

[0017] By using the traffic light control scheme provided above, this application embodiment determines whether a phase switch of the traffic lights is needed based on the acquired pedestrian, non-motorized vehicle, and motorized vehicle data for the corresponding traffic direction at the intersection. It adjusts the green light phase to a yellow light phase and delays the green light phase according to the actual situation. This allows for real-time matching of traffic light control strategies to meet actual needs based on traffic conditions and reduces the probability of traffic accidents. Furthermore, in some embodiments, in response to the need for a phase switch of the traffic lights for the corresponding traffic direction at the intersection, a delay is applied after the corresponding remaining time. The green light phase of the traffic lights for the corresponding traffic direction at the intersection is switched to a yellow light phase, and the yellow light phase is delayed. This ensures that all pedestrians can safely cross the intersection, guaranteeing pedestrian safety. Attached Figure Description

[0018] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, and the same or corresponding reference numerals denote the same or corresponding parts, wherein:

[0019] Figure 1 An exemplary flowchart of a traffic light control method according to an embodiment of this application is shown;

[0020] Figure 2 An exemplary flowchart illustrating the process of determining traffic light phase switching according to an embodiment of this application is shown;

[0021] Figure 3 An exemplary flowchart illustrating the process of determining the delay of a traffic light after a phase switch, according to an embodiment of this application, is shown.

[0022] Figure 4 An exemplary flowchart illustrating the delay time for obtaining the yellow phase of a traffic light according to an embodiment of this application is shown;

[0023] Figure 5 An exemplary structural block diagram of a traffic light control system according to an embodiment of this application is shown. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] It should be understood that the terms "comprising" and "including" used in the specification and claims of this application indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0026] It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this specification and claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this specification and claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0027] As used in this specification and claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0028] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0029] Figure 1 An exemplary flowchart of a traffic light control method 100 according to an embodiment of this application is shown.

[0030] like Figure 1 As shown, in step S110, pedestrian data, non-motorized vehicle data, motorized vehicle data, traffic light green phase time data, and motorized vehicle data for the non-traffic directions of the intersection are acquired respectively. Specifically, pedestrian data includes: pedestrian flow, pedestrian speed, and pedestrian position; non-motorized vehicle data includes: non-motorized vehicle flow, non-motorized vehicle speed, and non-motorized vehicle position; traffic light green phase time data includes: the duration of the green phase and the currently set total time; and motorized vehicle data includes: motorized vehicle flow, motorized vehicle speed, and motorized vehicle position.

[0031] In the embodiments of this application, in addition to obtaining the specific data listed above, other data may also be obtained, and this application does not impose any restrictions on this.

[0032] Specifically, pedestrian and non-motorized vehicle data are obtained by collecting and processing data on pedestrians and non-motorized vehicles in the zebra crossing area of ​​the intersection, while motorized vehicle data is obtained by collecting and processing data on motorized vehicles in the motorized vehicle lanes outside the intersection area. By collecting and processing data on motorized vehicles in the motorized vehicle lanes outside the intersection area, it is possible to accurately obtain data on motorized vehicles about to enter the intersection area. This allows for a better understanding and management of traffic flow, improving road safety and traffic efficiency.

[0033] In the embodiments of this application, multiple cameras are installed in the zebra crossing area of ​​the intersection to collect video streams of pedestrians and non-motorized vehicles. Multiple cameras are also installed in the motor vehicle lanes outside the intersection area to collect video streams of motor vehicles in both the traveling and non-traveling directions. The motor vehicle lanes outside the intersection area can be areas at a preset distance from the intersection. Next, the collected pedestrian and non-motorized vehicle video streams and motor vehicle video streams are processed to obtain pedestrian data, non-motorized vehicle data, and motor vehicle data for the corresponding traveling direction at the intersection, as well as motor vehicle data for the corresponding non-traveling direction at the intersection. Specifically, users can set the preset distance value based on historical experience data and actual needs; this application does not impose any restrictions on this setting.

[0034] Specifically, one side of the zebra crossing area at the intersection is designated as the starting zebra crossing, and the other side as the stopping zebra crossing. A point on the starting zebra crossing in the direction of travel is designated as the origin of the real-world coordinate system. The line passing through the origin in the direction of travel is designated as the x-axis of the real-world coordinate system, and the line passing through the origin in the direction of non-traffic is designated as the y-axis. Simultaneously, using map data, the distances between zebra crossing areas and between lane areas in the direction of travel, as well as the distances between zebra crossing areas and between lane areas in the direction of non-traffic, are obtained. The coordinates of the stop zebra crossings in the direction of travel are obtained based on the distance between the zebra crossing areas in the intersection and the distance between the lane areas in the direction of travel. The coordinates of the starting line and stop line of the lane area in the direction of travel are obtained based on the distance between the zebra crossing areas in the intersection and the distance between the lane areas in the intersection and the distance between the lane areas in the direction of travel.

[0035] Next, the cameras transmit the captured video streams of pedestrians and non-motorized vehicles, as well as the video streams of motorized vehicles, to a backend server for processing. The backend server, according to a set frequency, extracts image frames from the pedestrian and non-motorized vehicle video streams and the motorized vehicle video streams respectively using video processing software or APIs. By counting the number of pedestrians detected in each frame and combining this with time-series information, the number of pedestrians passing through the intersection in each unit of time is calculated to obtain the pedestrian flow. Similarly, the number of non-motorized vehicles in each frame is recorded to obtain the non-motorized vehicle flow in each direction passing through the intersection. The number of motorized vehicles in each frame is also recorded to obtain the motorized vehicle flow in both the passing and non-passing directions in the motorized vehicle lanes outside the intersection area.

[0036] Simultaneously, deep learning models such as YOLO, SSD, or Faster R-CNN are used to perform target recognition processing on the image frames corresponding to the extracted pedestrian and non-motorized vehicle video streams and motorized vehicle video streams, respectively. Bounding boxes for pedestrians, non-motorized vehicles, and motorized vehicles are extracted, and the center point of the pedestrian's bounding box is used as the pixel coordinates for the pedestrian, the center point of the non-motorized vehicle's bounding box, and the center point of the motorized vehicle's bounding box. Then, a projection transformation is used to map the pixel coordinates to a real-world coordinate system, converting the obtained pixel coordinates into real-world coordinates to obtain the positions of pedestrians, non-motorized vehicles, and motorized vehicles.

[0037] Then, by comparing the changes in pedestrian position, non-motorized vehicle position, and motorized vehicle position in several consecutive frames, the distances of pedestrian displacement, non-motorized vehicle displacement, and motorized vehicle displacement in several consecutive frames are obtained. The distances are divided by the time difference between the consecutive frames to obtain the pedestrian speed, non-motorized vehicle speed, and motorized vehicle speed, respectively.

[0038] In the embodiments of this application, the duration of the green phase of the traffic light is the time that motor vehicles, pedestrians and non-motor vehicles corresponding to the non-traffic direction have been waiting at the intersection. The currently set total time is the total time that the green phase of the traffic light needs to last. The remaining time of the green phase of the traffic light can be obtained by subtracting the duration of the green phase of the traffic light from the currently set total time.

[0039] After obtaining the aforementioned data through step S110, in step S120, based on the obtained pedestrian data, non-motorized vehicle data and motorized vehicle data corresponding to the traffic direction of the intersection, it is determined whether it is necessary to switch the phase of the traffic lights corresponding to the traffic direction of the intersection.

[0040] In the embodiments of this application, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of the intersection is less than or equal to a first flow threshold, and the motorized vehicle flow in the corresponding direction of the intersection is less than or equal to a second flow threshold, it is determined that a phase switch is needed for the traffic lights in the corresponding direction of the intersection. Since the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of the intersection is less than or equal to the first flow threshold, and the motorized vehicle flow in the corresponding direction of the intersection is less than or equal to the second flow threshold, it indicates that the current traffic situation has not yet reached saturation, and there is no need to continuously maintain the green light phase. Timely phase switching of the traffic lights can effectively improve the overall traffic efficiency of the intersection.

[0041] Conversely to the aforementioned conditions requiring phase switching of traffic lights in the corresponding direction of travel at an intersection, if the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of travel at the intersection exceeds a first traffic flow threshold, and the motorized vehicle traffic in the corresponding direction of travel at the intersection is less than or equal to a second traffic flow threshold, then it is determined that phase switching of the traffic lights in the corresponding direction of travel at the intersection is not required. Alternatively, if the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of travel at the intersection exceeds the first traffic flow threshold, and the motorized vehicle traffic in the corresponding direction of travel at the intersection exceeds the second traffic flow threshold, then it is determined that phase switching of the traffic lights in the corresponding direction of travel at the intersection is not required. Or, if the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of travel at the intersection is less than or equal to the first traffic flow threshold, and the motorized vehicle traffic in the corresponding direction of travel at the intersection exceeds the second traffic flow threshold, then it is determined that phase switching of the traffic lights in the corresponding direction of travel at the intersection is not required.

[0042] In the embodiments of this application, the first flow threshold and the second flow threshold can be set according to actual needs and historical experience data, and this application does not impose any restrictions on them.

[0043] After step S120 is completed, in response to the need to switch the phase of the traffic lights for the corresponding traffic direction at the intersection, in step S130, the green phase of the traffic lights for the corresponding traffic direction at the intersection is immediately switched to the yellow phase, or the green phase of the traffic lights for the corresponding traffic direction at the intersection is switched to the yellow phase after its corresponding remaining time.

[0044] In embodiments of this application, in response to the need to switch the phase of traffic lights for the corresponding traffic direction at an intersection, it is also necessary to determine whether an immediate phase switch of the traffic lights for the corresponding traffic direction is required. If it is determined that an immediate phase switch of the traffic lights for the corresponding traffic direction is not required, the green phase of the traffic lights for the corresponding traffic direction is immediately switched to a yellow phase. If it is determined that an immediate phase switch of the traffic lights for the corresponding traffic direction is not required, it is then determined whether a delay is needed after the phase switch of the traffic lights for the corresponding traffic direction, thereby switching the green phase of the traffic lights for the corresponding traffic direction to a yellow phase after its corresponding remaining time, and whether to delay or not delay based on the determination result. The following is in conjunction with... Figure 2 The specific process involved here will be explained in detail.

[0045] Figure 2 An exemplary flowchart illustrating the process of determining traffic light phase switching according to an embodiment of this application is shown.

[0046] like Figure 2 As shown, in response to the need for phase switching of traffic lights in the corresponding traffic direction at the intersection, in step S210, based on the acquired pedestrian data, non-motorized vehicle data, motorized vehicle data, and motorized vehicle data in the non-traffic direction corresponding to the intersection, it is determined whether the phase of the traffic lights in the corresponding traffic direction needs to be switched immediately. In response to the need for immediate phase switching of traffic lights in the corresponding traffic direction at the intersection, in step S220, the green phase of the traffic lights in the corresponding traffic direction is immediately switched to a yellow phase. In response to the need not for immediate phase switching of traffic lights in the corresponding traffic direction at the intersection, in step S230, based on all acquired data, it is determined whether a delay is needed after the phase switching of traffic lights in the corresponding traffic direction at the intersection.

[0047] Then, in response to the absence of a delay after phase switching of the traffic lights for the corresponding traffic direction at the intersection, in step S240, the green phase of the traffic lights for the corresponding traffic direction at the intersection is switched to a yellow phase after its corresponding remaining time. In response to the absence of a delay after phase switching of the traffic lights for the corresponding traffic direction at the intersection, in step S250, the green phase of the traffic lights for the corresponding traffic direction at the intersection is switched to a yellow phase after its corresponding remaining time, and the yellow phase is delayed.

[0048] In an embodiment of this application, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a third flow threshold, the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a fourth flow threshold, and the motorized vehicle flow in the non-traffic direction of the intersection is greater than the motorized vehicle flow in the corresponding direction of traffic at the intersection, it is determined that the phase of the traffic light in the corresponding direction of traffic at the intersection needs to be switched immediately. The third flow threshold is less than the first flow threshold, and the fourth flow threshold is less than the second flow threshold.

[0049] That is, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the second flow threshold, the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is then compared with the third flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is compared with the fourth flow threshold and the motorized vehicle flow in the non-traffic direction corresponding to the intersection, in order to determine whether the phase of the traffic light in the corresponding direction of traffic at the intersection needs to be switched immediately.

[0050] In the embodiments of this application, by comparing the traffic flow of vehicles in the corresponding direction of travel at the intersection with the traffic flow of vehicles in the corresponding non-traffic direction at the intersection, ineffective traffic light phase switching can be avoided. For example, if the sum of the pedestrian flow and the non-motorized vehicle flow in the corresponding direction of travel at the intersection is less than or equal to a third flow threshold, and the traffic flow of vehicles in the corresponding direction of travel at the intersection is less than or equal to a fourth flow threshold, but the traffic flow of vehicles in the corresponding non-traffic direction at the intersection is less than or equal to the traffic flow of vehicles in the corresponding direction of travel, immediately switching the traffic light phase will not improve traffic flow.

[0051] Conversely to the aforementioned condition requiring immediate phase switching of traffic lights in the corresponding direction of traffic at an intersection, the following conditions are met: the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of traffic at the intersection is less than or equal to a first traffic flow threshold, and the motorized vehicle traffic in the corresponding direction of traffic at the intersection is less than or equal to a second traffic flow threshold. If the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of traffic at the intersection is greater than a third traffic flow threshold, and the motorized vehicle traffic in the corresponding direction of traffic at the intersection is less than or equal to a fourth traffic flow threshold, and the motorized vehicle traffic in the non-traffic direction of the intersection is greater than the motorized vehicle traffic in the corresponding direction of traffic at the intersection, then it is determined that immediate phase switching of the traffic lights in the corresponding direction of traffic at the intersection is not required.

[0052] Alternatively, if the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the third flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the fourth flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the motorized vehicle flow in the corresponding non-traffic direction of the intersection, it is determined that it is not necessary to immediately switch the phase of the traffic lights in the corresponding direction of traffic at the intersection.

[0053] Alternatively, if the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the third flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the fourth flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the motorized vehicle flow in the corresponding non-traffic direction of the intersection, it is determined that it is not necessary to immediately switch the phase of the traffic lights in the corresponding direction of traffic at the intersection.

[0054] Alternatively, if the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the third flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the fourth flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the motorized vehicle flow in the corresponding non-traffic direction of the intersection, it is determined that it is not necessary to immediately switch the phase of the traffic lights in the corresponding direction of traffic at the intersection.

[0055] Alternatively, if the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the third flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the fourth flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the motorized vehicle flow in the corresponding non-traffic direction of traffic at the intersection, it is determined that it is not necessary to immediately switch the phase of the traffic lights in the corresponding direction of traffic at the intersection.

[0056] In the embodiments of this application, the third flow threshold can be set to 0, and the fourth flow threshold can be set to 0 or a number greater than 0 according to actual needs and empirical data. This application does not impose any restrictions here.

[0057] In the embodiments of this application, the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is first compared with a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is compared with a second flow threshold. If the comparison determines that a phase switch for the traffic light in the corresponding direction of traffic at the intersection is not required, then it is unnecessary to further compare the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection with a third flow threshold, or to compare the motorized vehicle flow in the corresponding direction of traffic at the intersection with a fourth flow threshold and the motorized vehicle flow in the non-traffic direction corresponding to the intersection. This improves the efficiency of the traffic light control system and reduces unnecessary operations.

[0058] In the embodiments of this application, when it is necessary to immediately switch the phase of the traffic lights for the corresponding travel direction at the intersection, that is, when the green light phase for the corresponding travel direction at the intersection no longer needs to be maintained, the green light phase of the traffic lights for the corresponding travel direction at the intersection is immediately switched to a yellow light phase. After the yellow light phase has lasted for its corresponding set time, the green light phase of the traffic lights for the non-traffic direction at the intersection begins to function, thereby ensuring that pedestrians, non-motorized vehicles, and motorized vehicles for the non-traffic direction at the intersection can pass through as quickly as possible, improving the traffic efficiency of the non-traffic direction.

[0059] In the embodiments of this application, when it is not necessary to immediately switch the phase of the traffic lights for the corresponding traffic direction at the intersection, it is also necessary to consider whether pedestrians and non-motorized vehicles can smoothly cross the zebra crossing area after the green phase of the traffic lights for the corresponding traffic direction at the intersection switches to the yellow phase after its corresponding remaining time, and during the process of the yellow phase continuing to run and switching to the red phase. That is, by delaying the yellow phase, pedestrians and non-motorized vehicles can safely cross the zebra crossing area before the traffic lights switch to the red phase. The following is combined with Figure 3 This specific process will be explained in detail.

[0060] Figure 3 An exemplary flowchart of the process for determining the delay of a traffic light after a phase switch, according to an embodiment of this application, is shown.

[0061] like Figure 3 As shown, in step S310, the time required for the last target to pass is obtained based on the pedestrian speed, pedestrian position, non-motorized vehicle speed, and non-motorized vehicle position in the corresponding traffic direction at the intersection, where the target is a pedestrian or a non-motorized vehicle. Next, in step S320, it is determined whether the time required for the last target to pass is greater than the remaining time of the green light phase of the traffic light. If the time required for the last target to pass is not greater than the remaining time of the green light phase, in step S330, it is determined that a delay is not required after the phase switch of the traffic light in the corresponding traffic direction at the intersection. If the time required for the last target to pass is greater than the remaining time of the green light phase, in step S340, it is determined that a delay is required after the phase switch of the traffic light in the corresponding traffic direction at the intersection.

[0062] In the embodiments of this application, the distance between a pedestrian and their corresponding starting or stopping zebra crossing area is obtained based on the pedestrian and non-motorized vehicle positions in the corresponding traffic direction of the intersection, the coordinates of the stop zebra crossing in the corresponding traffic direction of the intersection, and the origin of the coordinate system. Similarly, the distance between a non-motorized vehicle and its corresponding starting or stopping zebra crossing area is also obtained. Next, the time required for the current pedestrian to cross is obtained by dividing the obtained pedestrian distance by the pedestrian speed, and the time required for the current non-motorized vehicle to cross is obtained by dividing the obtained non-motorized vehicle distance by the non-motorized vehicle speed. Finally, the longest time obtained above is taken as the time required for the last target to cross.

[0063] Specifically, when the direction of movement of a pedestrian or non-motorized vehicle is towards the starting zebra crossing, the distance between the pedestrian or non-motorized vehicle and its corresponding starting zebra crossing area is obtained. When the direction of movement of a pedestrian or non-motorized vehicle is towards the stopping zebra crossing, the distance between the pedestrian or non-motorized vehicle and its corresponding stopping zebra crossing area is obtained.

[0064] In the embodiments of this application, when the time required for the last target to pass is less than or equal to the remaining time of the green light phase of the traffic light, it indicates that the remaining time of the green light phase is sufficient for the last target to pass through the zebra crossing area, and no delay is needed after the traffic light phase switch. At this time, the green light phase of the traffic light corresponding to the direction of travel at the intersection is switched to the yellow light phase after its corresponding remaining time. Then, after the yellow light phase runs for a preset time, it is switched to the red light phase.

[0065] In the embodiments of this application, if the time required for the last target to pass is greater than the remaining time of the green light phase of the traffic light, it indicates that the remaining time of the green light phase is insufficient for the last target to pass through the zebra crossing area, and a delay is required after the traffic light phase switch. At this time, the green light phase of the traffic light corresponding to the direction of travel at the intersection is switched to the yellow light phase after its corresponding remaining time. Then, the yellow light phase runs for a preset time and is delayed for a further period before being switched to the red light phase.

[0066] In the embodiments of this application, when the time required for the last target to pass is greater than the remaining time of the green light phase of the traffic light, the green light phase of the traffic light for the corresponding direction of travel at the intersection is switched to a yellow light phase after its corresponding remaining time, and the yellow light phase is delayed. This ensures the safe passage of pedestrians or non-motorized vehicles across the zebra crossing area. Furthermore, compared to delaying the green light phase to ensure the safe passage of pedestrians or non-motorized vehicles, this approach raises a sense of urgency among pedestrians or non-motorized vehicle drivers, leading them to cross more quickly. Furthermore, compared to delaying the green light phase, pedestrians or non-motorized vehicles that have not yet started crossing will begin to cross the zebra crossing during the green light phase, which will require recalculating the safe crossing time. If the green light phase is then delayed, the waiting time for non-traffic directions will increase significantly, still posing a safety hazard. However, by delaying the yellow light phase, pedestrians or non-motorized vehicles that have not yet started crossing will generally not begin to cross the zebra crossing during the yellow light phase. This ensures the safe passage of both pedestrians and non-motorized vehicles that have already started crossing and those that have not yet started crossing.

[0067] In the embodiments of this application, the specific process of obtaining the delay time after the green light phase of the traffic light at the intersection switches to the yellow light phase can be found in [reference needed]. Figure 4 .like Figure 4 As shown, in step S410, the difference between the time required for the last target to pass and the remaining time of the green light phase of the traffic light is used as the first difference. Next, in step S420, the difference between the set waiting tolerance time and the remaining duration of the green light phase is used as the second difference. Then, in step S430, it is determined whether the first difference is less than the second difference. If the first difference is less than the second difference, in step S440, the first difference is used as the delay time after the green light phase of the traffic light for the corresponding direction of traffic at the intersection switches to the yellow light phase. If the first difference is not less than the second difference, in step S450, the second difference is used as the delay time after the green light phase of the traffic light for the corresponding direction of traffic at the intersection switches to the yellow light phase.

[0068] In the embodiments of this application, the waiting time can be set based on historical experience data and experimental data, and this application does not impose any restrictions on it.

[0069] In embodiments of this application, when the time required for the last target to cross the intersection (first difference) is less than the difference between the set waiting tolerance time and the duration of the green light (second difference), sufficient time is given to ensure that pedestrians or non-motorized vehicles can safely cross the zebra crossing area. This helps reduce instances of pedestrians or non-motorized vehicles running red lights and lowers the risk of traffic accidents.

[0070] In the embodiments of this application, when the time required for the last target to pass through the intersection (first difference) is not less than the difference between the set waiting tolerance time and the duration of the green light (second difference), the second difference is used as the delay time. This can meet the driver's psychological expectations to a certain extent, reduce the anxiety caused by the long waiting time, and thus reduce violations such as running yellow lights.

[0071] After step S120 is completed, in response to the fact that it is not necessary to switch the phase of the traffic lights for the corresponding traffic direction at the intersection, in step S140, the green phase of the traffic lights for the corresponding traffic direction at the intersection is delayed based on all the acquired data.

[0072] In the embodiments of this application, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than a second flow threshold, the delay time of the green light phase is obtained according to a first delay time calculation formula, wherein the first delay time calculation formula is: Among them, T m T is the time required, calculated from the vehicle traffic data for the corresponding direction of traffic at the intersection, to reduce the vehicle traffic flow in that direction to equal the second traffic flow threshold. th The set waiting time.

[0073] Specifically, when the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of the intersection is less than or equal to a first traffic flow threshold, and the motorized vehicle traffic in the corresponding direction of the intersection is greater than a second traffic flow threshold, traffic flow control at the intersection can be achieved simply by reducing the motorized vehicle traffic in the corresponding direction of the intersection to the second traffic flow threshold. More specifically, the time required for the motorized vehicle traffic in the corresponding direction of the intersection to decrease to equal the second traffic flow threshold is calculated using a trained neural network model based on vehicle speed, vehicle location, and vehicle traffic flow.

[0074] In the embodiments of this application, when the time required for the traffic flow of motor vehicles in the corresponding direction of the intersection to decrease to equal the second traffic flow threshold is greater than the waiting tolerance time, the waiting tolerance time is used as the delay time of the green light phase. This can prevent the anxiety of non-motorized vehicle owners, pedestrians, and motor vehicle drivers in the opposite direction of the intersection from committing violations due to excessively long waiting times.

[0075] In the embodiments of this application, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a second flow threshold, the delay time of the green light phase is obtained according to a second delay time calculation formula, wherein the second delay time calculation formula is: Among them, T n T is the time required, calculated using pedestrian and non-motorized vehicle data for the corresponding traffic directions at the intersection, to reduce the sum of pedestrian and non-motorized vehicle traffic flows in the corresponding traffic directions at the intersection to equal a first traffic flow threshold. th The set waiting time.

[0076] Specifically, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of the intersection exceeds a first flow threshold, and the motorized vehicle flow in the corresponding direction of the intersection is less than or equal to a second flow threshold, traffic flow control at the intersection can be achieved as long as the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of the intersection, calculated from pedestrian and non-motorized vehicle data, is reduced to the first flow threshold. More specifically, a trained neural network model calculates the time required for the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of the intersection to decrease to equal the first flow threshold based on pedestrian flow, pedestrian speed, pedestrian position, non-motorized vehicle flow, non-motorized vehicle speed, and non-motorized vehicle position.

[0077] In the embodiments of this application, when the time required to reduce the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of the intersection to equal the first traffic threshold is greater than the waiting tolerance time, the waiting tolerance time is used as the delay time of the green light phase. This can prevent the anxiety of non-motorized vehicle owners, pedestrians, and motorized vehicle drivers in the opposite direction of the intersection from committing violations due to excessively long waiting times.

[0078] In the embodiments of this application, when the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than or equal to a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than a second flow threshold, the delay time of the green light phase is obtained according to a third delay time calculation formula, wherein the third delay time calculation formula is: Among them, T n T is the time required, calculated using pedestrian and non-motorized vehicle data for the corresponding traffic directions at the intersection, to reduce the sum of pedestrian and non-motorized vehicle traffic flows in the corresponding traffic directions at the intersection to equal a first traffic flow threshold. mT is the time required, calculated from the vehicle traffic data for the corresponding direction of traffic at the intersection, to reduce the vehicle traffic flow in that direction to equal the second traffic flow threshold. th ω is the set waiting patience time. n For T n The corresponding weight, ω m For T m The corresponding weights.

[0079] Specifically, when the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction at an intersection exceeds a first traffic flow threshold, and the motorized vehicle traffic in the corresponding direction exceeds a second traffic flow threshold, it is necessary to control the reduction of the sum of pedestrian and non-motorized vehicle traffic and the reduction of motorized vehicle traffic based on their importance. This can be achieved by setting weights. More specifically, a trained neural network model calculates the time required for the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction at the intersection to decrease to equal the first traffic flow threshold, based on pedestrian traffic, pedestrian speed, pedestrian position, non-motorized vehicle traffic, non-motorized vehicle speed, and non-motorized vehicle position. Then, the delay time of the green light phase is obtained by weighted summation of the acquired times.

[0080] In the embodiments of this application, when the weighted average of the time required to reduce the sum of pedestrian and non-motorized vehicle traffic in the corresponding direction of the intersection to equal the first traffic threshold and the time required to reduce the motorized vehicle traffic in the corresponding direction of the intersection to equal the second traffic threshold (which is greater than the waiting tolerance time) is greater than the waiting tolerance time, the waiting tolerance time is used as the delay time of the green light phase. This can prevent the anxiety of non-motorized vehicle owners, pedestrians, and motorized vehicle drivers in the non-traffic direction of the intersection from being caused by excessively long waiting times, thus avoiding violations.

[0081] In the embodiments of this application, the aforementioned T n The corresponding weight ω n and T m The corresponding weight ω m The settings can be adjusted according to actual needs and experience data; this application does not impose any restrictions on them.

[0082] In summary, through the traffic light control scheme provided above, this application embodiment determines whether a phase switch of the traffic lights is needed based on the acquired pedestrian, non-motorized vehicle, and motorized vehicle data for the corresponding traffic direction at the intersection. It adjusts the green light phase to a yellow light phase and delays the green light phase according to the actual situation. This allows for real-time matching of traffic light control strategies to meet actual needs based on traffic conditions and reduces the probability of traffic accidents. Furthermore, in some embodiments, in response to the need for a phase switch of the traffic lights for the corresponding traffic direction at the intersection, a delay is applied after the corresponding remaining time. The green light phase of the traffic lights for the corresponding traffic direction at the intersection is switched to a yellow light phase, and the yellow light phase is delayed. This ensures that all pedestrians can safely cross the intersection, guaranteeing pedestrian safety.

[0083] This application also provides a traffic light control system, which can use the aforementioned traffic light control method 100 to control the traffic lights, or other traffic light control methods can be used to control the traffic lights. This application does not impose any limitations on this.

[0084] Figure 5 An exemplary structural block diagram of a traffic light control system according to an embodiment of this application is shown.

[0085] like Figure 5 As shown, the system 500 includes a data acquisition module 510, a judgment module 520, and an execution module 530. In the embodiments of this application, the data acquisition module 510, the judgment module 520, and the execution module 530 may be separate units or integrated in the same backend server; this application does not impose any restrictions here.

[0086] Specifically, the data acquisition module 510 is used to acquire pedestrian data, non-motorized vehicle data, motorized vehicle data, green light phase time data of traffic lights, and motorized vehicle data of non-traffic directions corresponding to the intersection, respectively.

[0087] Specifically, the judgment module 520 is used to determine whether it is necessary to switch the phase of the traffic lights in the corresponding direction of traffic at the intersection based on the acquired pedestrian data, non-motorized vehicle data and motorized vehicle data of the intersection.

[0088] Specifically, the execution module 530 is used to respond to the need to switch the phase of the traffic lights in the corresponding direction of traffic at the intersection by immediately switching the green phase of the traffic lights in the corresponding direction of traffic at the intersection to the yellow phase or by switching the green phase of the traffic lights in the corresponding direction of traffic at the intersection to the yellow phase after its corresponding remaining time; and to respond to the need not to switch the phase of the traffic lights in the corresponding direction of traffic at the intersection by delaying the green phase of the traffic lights in the corresponding direction of traffic at the intersection based on all the acquired data.

[0089] When system 500 uses the aforementioned traffic light control method 100 to control traffic lights, the data acquisition module 510 executes the aforementioned step S110, the judgment module 520 executes the aforementioned step S120, and the execution module 530 executes the aforementioned steps S130 and S140. The specific execution process can be found above and will not be repeated here.

[0090] While numerous embodiments of this application have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many modifications, alterations, and alternatives will arise for those skilled in the art without departing from the spirit and intent of this application. It should be understood that various alternatives to the embodiments of this application described herein may be employed in the practice of this application. The appended claims are intended to define the scope of protection of this application and therefore cover equivalents or alternatives within the scope of these claims.

Claims

1. A method for controlling traffic lights, characterized in that, include: The system acquires pedestrian data, non-motorized vehicle data, motorized vehicle data, traffic light green phase time data, and motorized vehicle data for the non-traffic directions at the intersection. Pedestrian data includes pedestrian flow, pedestrian speed, and pedestrian position; non-motorized vehicle data includes non-motorized vehicle flow, non-motorized vehicle speed, and non-motorized vehicle position; traffic light green phase time data includes the green phase duration and the currently set total time; and motorized vehicle data includes motorized vehicle flow, motorized vehicle speed, and motorized vehicle position. Based on the acquired pedestrian, non-motorized vehicle, and motorized vehicle data for the corresponding traffic direction at the intersection, it is determined whether the traffic lights for the corresponding traffic direction at the intersection need to be switched in phase. In response to the need to switch the phase of the traffic lights for the corresponding direction of traffic at the intersection, the green phase of the traffic lights for the corresponding direction of traffic at the intersection is immediately switched to the yellow phase, or the green phase of the traffic lights for the corresponding direction of traffic at the intersection is switched to the yellow phase after its corresponding remaining time. In response to the lack of phase switching for traffic lights in the corresponding traffic direction at the intersection, the green light phase of the traffic lights in the corresponding traffic direction at the intersection is delayed based on all acquired data; Based on all the acquired data, the green light phase of the traffic lights for the corresponding traffic directions at the intersection is delayed, including: When the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than a second flow threshold, the delay time of the green light phase is obtained according to the first delay time calculation formula, whereby the first delay time calculation formula is: Among them, T m T is the time required, calculated from the vehicle traffic data for the corresponding direction of traffic at the intersection, to reduce the vehicle traffic flow in that direction to equal the second traffic flow threshold. th The set waiting patience time; When the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection exceeds a first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to a second flow threshold, the delay time of the green light phase is obtained according to the second delay time calculation formula, whereby: Among them, T n T is the time required, calculated using pedestrian and non-motorized vehicle data for the corresponding traffic directions at the intersection, to reduce the sum of pedestrian and non-motorized vehicle traffic flows in the corresponding traffic directions at the intersection to equal a first traffic flow threshold. th The set waiting time.

2. The traffic light control method according to claim 1, characterized in that, In response to the need to switch the phase of the traffic lights in the corresponding direction of traffic at the intersection, the system determines whether to switch the phase of the traffic lights in the corresponding direction of traffic at the intersection immediately based on the acquired pedestrian data, non-motorized vehicle data, motorized vehicle data in the corresponding direction of traffic at the intersection and motorized vehicle data in the non-traffic direction corresponding to the intersection. In response to the need to immediately switch the phase of the traffic lights for the corresponding traffic direction at the intersection, the green phase of the traffic lights for the corresponding traffic direction at the intersection is immediately switched to the yellow phase.

3. The traffic light control method according to claim 2, characterized in that, In response to the fact that it is not necessary to immediately switch the phase of the traffic lights for the corresponding traffic direction at the intersection, a delay is determined based on all the acquired data to determine whether a delay is needed after switching the phase of the traffic lights for the corresponding traffic direction at the intersection. In response to the fact that there is no need to delay after the traffic light phase switching for the corresponding direction of traffic at the intersection, the green phase of the traffic light for the corresponding direction of traffic at the intersection will be switched to the yellow phase after its corresponding remaining time. In response to the need for a delay after the traffic lights for the corresponding traffic direction at the intersection have switched phases, the green phase of the traffic lights for the corresponding traffic direction at the intersection will be switched to the yellow phase after its corresponding remaining time, and the yellow phase will be delayed.

4. The traffic light control method according to claim 2, characterized in that, When the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the second flow threshold, it is determined that the traffic lights in the corresponding direction of traffic at the intersection need to be switched.

5. The traffic light control method according to claim 4, characterized in that, When the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the third flow threshold, the motorized vehicle flow in the corresponding direction of traffic at the intersection is less than or equal to the fourth flow threshold, and the motorized vehicle flow in the non-traffic direction of the intersection is greater than the motorized vehicle flow in the corresponding direction of traffic at the intersection, it is determined that the phase of the traffic light in the corresponding direction of traffic at the intersection needs to be switched immediately. Among them, the third flow threshold is less than the first flow threshold, and the fourth flow threshold is less than the second flow threshold.

6. The traffic light control method according to claim 3, characterized in that, The time required for the last target to pass is obtained based on the pedestrian speed, pedestrian position, non-motorized vehicle speed, and non-motorized vehicle position in the corresponding direction of traffic at the intersection. The target is either a pedestrian or a non-motorized vehicle. Determine whether the time required for the last target to pass is greater than the remaining time of the green light phase of the traffic light; If the time required for the last target to pass is not greater than the remaining time of the green light phase of the traffic light, it is determined that no delay is needed after the traffic light phase switch for the corresponding direction of traffic at the intersection; If the time required for the last target to pass is greater than the remaining time of the green light phase of the traffic light, it is determined that a delay is needed after the traffic light phase switch for the corresponding direction of traffic at the intersection.

7. The traffic light control method according to claim 6, characterized in that, The first difference is the difference between the time required for the last target to pass and the remaining time of the green light phase of the traffic light. The difference between the set waiting patience time and the duration of the green light phase is used as the second difference; Determine whether the first difference is less than the second difference; When the first difference is less than the second difference, the first difference is used as the delay time after the green light phase of the traffic light in the corresponding direction of traffic at the intersection switches to the yellow light phase; When the first difference is not less than the second difference, the second difference is used as the delay time after the green light phase of the traffic light in the corresponding direction of traffic at the intersection switches to the yellow light phase.

8. The traffic light control method according to claim 7, characterized in that, The delay of the green light phase of the traffic lights for the corresponding traffic direction at the intersection, based on all the acquired data, also includes: When the sum of pedestrian flow and non-motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than or equal to the first flow threshold, and the motorized vehicle flow in the corresponding direction of traffic at the intersection is greater than the second flow threshold, the delay time of the green light phase is obtained according to the third delay time calculation formula, whereby the third delay time calculation formula is: Among them, T n T is the time required, calculated using pedestrian and non-motorized vehicle data for the corresponding traffic directions at the intersection, to reduce the sum of pedestrian and non-motorized vehicle traffic flows in the corresponding traffic directions at the intersection to equal a first traffic flow threshold. m T is the time required, calculated from the vehicle traffic data for the corresponding direction of traffic at the intersection, to reduce the vehicle traffic flow in that direction to equal the second traffic flow threshold. th ω is the set waiting patience time. n For T n The corresponding weight, ω m For T m The corresponding weights.

9. A traffic light control system, characterized in that, The system controls traffic lights using the traffic light control method as described in any one of claims 1-8, wherein the system comprises: The data acquisition module is used to acquire pedestrian data, non-motorized vehicle data, motorized vehicle data, green light phase time data of traffic lights, and motorized vehicle data in the non-traffic direction corresponding to the intersection. The judgment module is used to determine whether the traffic lights at the intersection need to be switched in phase based on the pedestrian data, non-motorized vehicle data and motorized vehicle data of the corresponding traffic direction at the intersection. The execution module is used to respond to the need to switch the phase of the traffic lights for the corresponding traffic direction at the intersection by immediately switching the green phase of the traffic lights for the corresponding traffic direction at the intersection to the yellow phase or by switching the green phase of the traffic lights for the corresponding traffic direction at the intersection to the yellow phase after the corresponding remaining time; and to respond to the need not to switch the phase of the traffic lights for the corresponding traffic direction at the intersection by delaying the green phase of the traffic lights for the corresponding traffic direction at the intersection based on all acquired data.

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