A traffic road condition identification analysis method based on a traffic large model

Abstract

The application provides a traffic road condition identification analysis method based on a traffic big model, relates to the technical field of traffic control, and is used for relieving the congestion condition of a congested intersection without destroying the coordination effect between intersections. The traffic road condition identification analysis method based on the traffic big model can include: judging whether a target intersection meets a congestion condition; if it is determined that the target intersection meets the congestion condition, determining a plurality of to-be-adjusted signal lights based on the target intersection and a coordination direction, the coordination direction being a preconfigured direction; performing an add-drop control strategy on the plurality of to-be-adjusted signal lights according to a preconfigured sequence; and performing a transition control strategy on the plurality of to-be-adjusted signal lights after it is determined that the target intersection meets a congestion removal condition.

Description

Technical Field

[0001] This application relates to the field of traffic control and discloses a traffic condition identification and analysis method based on a large traffic model. Background Technology

[0002] Traffic congestion is common during morning and evening rush hours, and easing congestion and ensuring smooth traffic flow are important aspects of urban traffic management. One related technology involves adjusting the green light ratio in each direction at congested intersections, but this could potentially cause congestion or overflow at other intersections.

[0003] With the accelerating pace of urbanization and the continuous growth of motor vehicle ownership, traffic congestion has become a common problem in modern urban management. Especially during morning and evening rush hours, traffic saturation and surges in queue length frequently occur at key intersections or along main roads, severely impacting the efficiency of the road network and the travel experience of citizens. Therefore, alleviating congestion and ensuring smooth traffic flow has become one of the core tasks of urban traffic management.

[0004] In related technologies, methods such as single-point signal control or arterial coordinated control are commonly used to address localized congestion. Common practices include dynamically adjusting signal timing based on detector data, such as increasing the green light time in the congested direction (i.e., adjusting the "green light ratio"), or implementing inductive control and adaptive control strategies. Although these methods can alleviate congestion at intersections to some extent, their control perspective is often limited to a single node or a single direction, lacking a comprehensive consideration of the coordination of related intersections and the overall road network. Summary of the Invention

[0005] This application provides a traffic condition identification and analysis method based on a large traffic model. The method identifies and analyzes traffic intersections based on the large traffic model, which can alleviate congestion at congested intersections without disrupting the coordination between intersections.

[0006] Firstly, this application provides a traffic condition identification and analysis method based on a large traffic model, the method comprising:

[0007] Determine whether the target intersection meets the congestion criteria;

[0008] If the target intersection is determined to meet the congestion conditions, then based on the target intersection and the coordination direction, multiple traffic lights to be adjusted are determined, and the coordination direction is a pre-configured direction;

[0009] According to a predetermined order, an addition and release control strategy is executed on the plurality of traffic lights to be adjusted;

[0010] After determining that the target intersection meets the conditions for relieving congestion, a transition control strategy is implemented for the multiple traffic lights to be adjusted.

[0011] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application, wherein determining multiple traffic lights to be adjusted based on the target intersection and the coordination direction includes:

[0012] In the coordinated direction, the traffic lights at the target intersection, the traffic lights at a first number of upstream intersections and a second number of downstream intersections of the target intersection on the target trunk line are identified as the plurality of traffic lights to be adjusted. The target trunk line is the trunk line to which the target intersection belongs, and the target trunk line includes multiple intersections; or,

[0013] The traffic lights at the target intersection in the coordinated direction, the traffic lights at the upstream intersections of the first number of target intersections and the traffic lights at the downstream intersections of the target intersections in the target trunk line, and the traffic lights at the downstream intersections in the non-coordinated direction are identified as the plurality of traffic lights to be adjusted.

[0014] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application, before implementing the addition control strategy for the plurality of traffic lights to be adjusted, the method further includes:

[0015] The release duration of the first signal light in the coordination direction among the plurality of signal lights to be adjusted is determined; and the issuance time corresponding to the first signal light is determined, wherein the issuance time represents the time when the release control command is sent to the signal corresponding to the first signal light;

[0016] If there is a second signal light in a non-coordinated direction among the plurality of signal lights to be adjusted, then the duration of the second signal light's placement is determined.

[0017] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application includes a control strategy for adding or removing traffic lights, comprising:

[0018] Based on the issuance time corresponding to the first traffic light, a release control command corresponding to the first traffic light is sent to the signal controller of the first traffic light. The release control command corresponding to the first traffic light is used to instruct the signal controller of the first traffic light to work according to the release control cycle and the release duration corresponding to the first traffic light after the current control cycle ends.

[0019] If the second signal light is among the plurality of signals to be adjusted, after determining the release duration of the second signal light, a release control command corresponding to the second signal light is sent to the signal controller of the second signal light. The release control command corresponding to the second signal light is used to instruct the signal controller of the second signal light to work according to the release control cycle and the release duration corresponding to the second signal light after the current control cycle ends.

[0020] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application, wherein determining the issuance time corresponding to the first traffic light includes:

[0021] The maximum adjustment cycle coefficient (kmax) is determined based on the maximum distance corresponding to all the first traffic lights.

[0022] Based on the adjustment cycle set, a reference time set corresponding to any first traffic light is determined; wherein, the adjustment cycle set includes multiple adjustment cycle parameters, each adjustment cycle parameter being greater than or equal to a first value, and each adjustment cycle parameter being less than or equal to the maximum adjustment cycle coefficient (kmax), and the adjustment cycle parameters being integers; the reference time set corresponding to any first traffic light includes multiple adjustment time parameters, the multiple adjustment time parameters corresponding one-to-one with the multiple adjustment cycle parameters, and each adjustment time parameter being determined based on the corresponding adjustment cycle parameter and the non-departure duration (gn) of any first traffic light;

[0023] From the set of reference times corresponding to all first traffic lights, the adjustment period parameter corresponding to the smallest adjustment time parameter is determined as the target adjustment period coefficient (k').

[0024] Based on the pre-acquired starting deviation (On) of any one of the first traffic lights, the starting deviation (S1) of the traffic lights at the upstream intersection of the target intersection in the coordination direction, the preset addition control cycle (TC), and the target adjustment cycle coefficient (k'), the initial issuance interval (dtn') of any one of the first traffic lights is calculated. The initial issuance interval represents the interval between the issuance time of any one of the first traffic lights and the issuance time of the traffic lights at the upstream intersection of the target intersection in the coordination direction.

[0025] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application, wherein determining the issuance time corresponding to the first traffic light further includes:

[0026] If the initial issuance interval of all first traffic lights meets the preset issuance conditions, then the issuance time of each first traffic light is determined based on the issuance time of the first traffic light at the start of issuance and the initial issuance interval of each first traffic light. The first traffic light at the start of issuance is the traffic light of the upstream intersection of the target intersection in the coordinated direction.

[0027] If at least one of the first traffic lights does not meet the preset transmission conditions in its initial transmission interval, the first traffic light with the smallest initial transmission interval among all the first traffic lights is selected as the starting first traffic light, and the corrected transmission interval of any one of the first traffic lights is calculated. The corrected transmission interval of any one of the first traffic lights is the sum of the absolute values ​​of the initial transmission interval of the any one of the first traffic lights and the initial transmission interval of the starting first traffic light. Based on the transmission time of the starting first traffic light and the corrected transmission interval of each first traffic light, the transmission time of each first traffic light is determined.

[0028] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application, wherein the step of implementing a transition control strategy for the plurality of traffic lights to be adjusted includes:

[0029] For any intersection to which a traffic light to be adjusted belongs, the large transition control cycle and small transition control cycle of the intersection are determined based on the starting deviation of the operation of the intersection.

[0030] Based on the minimum green phase of the intersection and the coordination direction, the compression control cycle of the intersection is determined;

[0031] Based on the compression control cycle of the intersection and the default maximum control cycle of the intersection, a transition control cycle is selected from the large transition control cycle and the small transition control cycle.

[0032] The traffic signal controllers that control all the traffic lights at the intersection operate according to the selected transition control cycle.

[0033] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application includes any one of the following congestion conditions:

[0034] The traffic index of the target intersection on the entrance road segment in the coordinated direction is greater than a preset first index threshold, and the duration is greater than a preset first duration.

[0035] The queue length at the entrance lane of the target intersection in the coordinated direction is greater than the length threshold corresponding to the target intersection, and the duration is greater than the preset first duration.

[0036] Upon receiving a congestion release instruction from the management device, the congestion release instruction indicates that the target intersection is congested in the coordinated direction, and the trunk road to which the target intersection belongs belongs to a preset trunk road set.

[0037] In one possible implementation, the traffic condition identification and analysis method based on a large traffic model provided in this application includes any one of the following conditions for resolving congestion:

[0038] The traffic index of the target intersection at the entrance road segment in the coordinated direction is less than or equal to a preset second index threshold, and the duration is greater than a preset second duration.

[0039] The queue length at the target intersection in the direction of coordination is less than a preset length threshold, and the duration is less than the second duration.

[0040] The traffic index of the road segment in the intersecting direction of the target intersection is greater than the preset third index threshold, and its time duration is greater than the preset third duration. The intersecting direction is the direction that has an intersecting relationship with the coordinating direction.

[0041] The queue length of the approach lanes in the intersecting directions of the target intersection is greater than the preset length threshold, and the duration is greater than the third duration.

[0042] The road sections at the target intersection in the intersecting directions are experiencing bottlenecks.

[0043] The beneficial effects of the embodiments of this application are as follows:

[0044] This application provides a traffic condition identification and analysis method and related apparatus based on a large traffic model. The method determines whether a target intersection meets congestion conditions. If the target intersection meets congestion conditions, multiple traffic lights to be adjusted are identified based on the target intersection and a pre-configured direction. A release control strategy is executed on these multiple traffic lights in a predetermined order. By coordinating the release control strategy on these multiple traffic lights and coordinating their operation, congestion in the coordinating direction can be alleviated. A transition control strategy is then executed on these multiple traffic lights, and after a transition operation, each traffic light resumes its original operation, preventing new congestion after the release. This ensures that the coordination between intersections is not disrupted during and after the release operation.

[0045] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram illustrating an application scenario provided in the embodiments of this application;

[0048] Figure 2 A flowchart of a traffic condition identification and analysis method based on a large traffic model is provided for an embodiment of this application;

[0049] Figure 3 This is a schematic diagram of multiple traffic lights to be adjusted;

[0050] Figure 4 This is a schematic diagram of another type of multiple traffic lights to be adjusted;

[0051] Figure 5 A flowchart of a traffic condition identification and analysis method based on a large traffic model is provided for an embodiment of this application;

[0052] Figure 6 A schematic diagram showing the coordinated and non-coordinated directions at an intersection;

[0053] Figure 7 A schematic diagram showing the coordinated and non-coordinated directions at an intersection;

[0054] Figure 8 A flowchart illustrating a traffic condition identification and analysis method based on a large traffic model, provided for an embodiment of this application. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. 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. Unless otherwise specified, the embodiments and features in the embodiments of this application can be arbitrarily combined with each other. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown here.

[0056] The terms "first" and "second" in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the term "comprising" and any variations thereof are intended to cover non-exclusive protection. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices. The term "multiple" in this application can mean at least two, for example, two, three, or more, and the embodiments of this application do not impose limitations.

[0057] The data collection, dissemination, and use in this application all comply with relevant national laws and regulations.

[0058] First, let's introduce some application scenarios of this application, specifically a certain number of intersections within a certain area. In particular, urban environments have numerous intersections. These numerous intersections can be divided into multiple arterial roads, each of which can include a series of consecutive intersections and road segments. Each arterial road includes at least one direction. For example, south to north, north to south, east to west, west to east, northeast to southwest, southwest to northeast, southeast to northwest, northwest to southeast, etc.

[0059] In practical applications, trunk roads can refer to highways that occupy a main position and play a leading role in the highway network within a certain area, and have strong economic, cultural and other important service functions.

[0060] like Figure 1 As shown, Figure 1 The diagram shows the target arterial road and other road segments intersecting with it. The target arterial road consists of multiple intersections: intersection P, intersection M, intersection A, intersection B, and intersection D. It is assumed that the target arterial road runs from north to south in the coordinated direction, i.e., from intersection P to intersection M. The other road segments intersecting with the target arterial road are road segment C and road segment E. Vehicles exiting the coordinated direction at intersection A can reach intersecting road segment C. Vehicles exiting the coordinated direction at intersection B can reach intersecting road segment E. Figure 1 Intersections on the main road leading to the target are marked with white circles, while intersections on non-target main roads are marked with black circles.

[0061] In general, in the field of traffic management, among multiple arterial roads, those requiring congestion prevention are called coordinated arterial roads. The direction on a coordinated arterial road where congestion prevention is needed is called the coordinated direction of the arterial road. In practical applications, there are many situations requiring congestion prevention, such as during morning and evening rush hours, and in extreme weather conditions, all of which necessitate preventing or promptly alleviating congestion.

[0062] Please combine Figure 1 Along the target trunk line, the intersections are arranged in the following order: intersection P, intersection M, intersection A, intersection B, and intersection D. Along the target trunk line, the intersection in the preceding order is the upstream intersection of the subsequent intersection, and the intersection in the following order is the downstream intersection of the preceding intersection. For example, intersection P is the upstream intersection of intersection M. Intersections A, B, and D are all downstream intersections of intersection M. Similarly, intersections P and M are both upstream intersections of intersection A, and intersections B and D are both downstream intersections of intersection A.

[0063] Figure 2 An exemplary embodiment illustrates a traffic condition identification and analysis method based on a large traffic model. This method can be executed by a traffic signal controller or a traffic management system. The method includes the following steps:

[0064] S201, determine whether the target intersection meets the congestion conditions.

[0065] In practical implementation, the traffic condition identification and analysis method based on a large traffic model can be executed by a traffic signal controller. The traffic signal controller can be implemented as a management device that manages multiple intersections. It can be an electronic device that controls traffic lights, possessing capabilities such as data transmission and reception, data processing, and control of the traffic light operation. The target intersection can be any one of the multiple intersections. Similarly, the traffic condition identification and analysis method based on a large traffic model can be executed by a traffic management system. The traffic management system can manage multiple intersections, and the target intersection can be any one of the aforementioned managed intersections.

[0066] Optionally, the multiple intersections managed by the traffic signal controller or traffic management system may include intersections on multiple arterial roads and other roads. The target intersection can be any intersection on an arterial road. In other words, the traffic condition identification and analysis method based on a large traffic model provided in this application embodiment can be used for intersections on key managed arterial roads.

[0067] For ease of explanation, the following example illustrates the traffic condition identification and analysis method based on a large traffic model, using a traffic signal controller. It is understood that the process or method by which a traffic management system executes the traffic condition identification and analysis method based on a large traffic model is similar to that of a traffic signal controller, and the similarities will not be elaborated further.

[0068] S202, if it is determined that the target intersection meets the congestion conditions, then based on the target intersection and the coordination direction, a number of traffic lights to be adjusted are determined, and the coordination direction is a pre-configured direction.

[0069] In practice, traffic signal controllers can identify multiple traffic lights requiring coordinated adjustment based on the target intersection and the coordinating direction. In this application, these multiple traffic lights requiring coordinated adjustment are referred to as multiple traffic lights to be adjusted. By adjusting the operation of these multiple traffic lights to be adjusted, congestion at the target intersection in the coordinating direction can be alleviated through their coordinated operation.

[0070] S203, according to a predetermined order, execute the addition and release control strategy on the plurality of traffic lights to be adjusted.

[0071] In practice, traffic signal controllers can implement a release control strategy for multiple signals to be adjusted based on their sequence, such as the intersection sequence (signal light sequence) along the coordinating direction. For example, increasing the green time of each signal to be adjusted in the coordinating direction also increases the green light ratio of the signal in the coordinating direction.

[0072] S204, after determining that the target intersection meets the conditions for relieving congestion, a transition control strategy is executed on the plurality of traffic lights to be adjusted.

[0073] In practice, after implementing the additional control strategy for multiple traffic lights to be adjusted, the traffic signal controller can determine in real time or periodically whether the target intersection meets the conditions for resolving congestion. If the target intersection meets the conditions for resolving congestion, it indicates that the additional control strategy for the target intersection can be terminated. If the target intersection does not meet the conditions for resolving congestion, it indicates that the additional control strategy for the target intersection cannot be terminated.

[0074] After determining that the target intersection meets the conditions for congestion relief, the traffic signal controller can execute a transitional control strategy on the multiple traffic lights to be adjusted (i.e., the multiple traffic lights to be adjusted) participating in the additional control strategy. If the traffic lights are directly controlled to operate in their original mode after congestion relief, it can easily cause new congestion. In this embodiment, the traffic signal controller coordinates the execution of a transitional control strategy on the multiple traffic lights to be adjusted, and after a transitional operation based on the coordination between the multiple traffic lights to be adjusted, the traffic lights are then put back into their original operating mode.

[0075] In one possible implementation, in step 201, the congestion condition may include at least one of the following conditions:

[0076] Condition 1: The traffic index of the entrance road segment of the target intersection in the coordination direction is greater than a preset first index threshold and the duration is greater than a preset first duration. The coordination direction is a pre-configured direction.

[0077] Condition 2: The queue length of the entrance lane at the target intersection in the coordinated direction is greater than the length threshold corresponding to the target intersection, and the duration is greater than a preset first duration.

[0078] Condition 3: The traffic signal controller receives a congestion release instruction from the management equipment, the congestion release instruction indicating that the target intersection is congested in the coordinated direction, and the trunk road to which the target intersection belongs belongs to a preset trunk road set.

[0079] In practice, a traffic signal controller can determine that a target intersection meets any one of the congestion conditions.

[0080] In some examples, traffic signal controllers can determine whether a target intersection meets condition 1 based on internet data. The traffic signal controller can acquire the traffic index of the target intersection's approach road segment in the coordinating direction in real time. The traffic signal controller can determine whether this traffic index is greater than a preset first index threshold. If the traffic index is greater than the preset first index threshold, the traffic signal controller can determine whether the duration of the traffic index exceeding the first index threshold is greater than a preset first duration. If the traffic index of the target intersection is greater than the first index threshold and the duration is greater than the preset first duration, then the target intersection is determined to meet condition 1, which is also the congestion condition. Optionally, the first index threshold and the first duration can be configured according to the actual application scenario. For example, the first index threshold can be configured to 6, and the preset first duration can be configured to 10.

[0081] In other examples, traffic signal controllers can use radar detectors to obtain the queue length of the approach lanes at the target intersection in the coordinating direction. If the queue length is greater than the length threshold corresponding to the target intersection, and the duration for which the queue length is greater than the corresponding length threshold is greater than the aforementioned first duration, then the target intersection is determined to meet condition 2, which is also the target intersection meeting the congestion condition.

[0082] Optionally, the length threshold corresponding to the target intersection is related to the length of the road segment to which the target intersection belongs. Table 1 shows the relationship between the road segment length and the length threshold corresponding to the road segment length.

[0083] Table 1

[0084]

[0085] Traffic signal controllers can use the length of the road segment to which the target intersection belongs as a length threshold, and use that length threshold as the length threshold for the target intersection. This is used to determine whether the target intersection meets condition 2.

[0086] In some examples, the traffic signal controller can interact with one or more management devices. Staff can trigger congestion release commands through the management devices. Optionally, staff can determine whether the target intersection is an intersection within a coordinated arterial road and whether the congestion direction at the target intersection is a preset coordinated direction. Once staff determines that the target intersection is an intersection within a coordinated arterial road and that the congestion direction at the target intersection is the preset coordinated direction, they send a congestion release command to the traffic signal controller through the management device, so that the traffic signal controller at least performs the operations in steps S202-S204. Alternatively, the management device can automatically determine whether the target intersection is an intersection within a coordinated arterial road and whether the congestion direction at the target intersection is the preset coordinated direction. The management device can send a congestion release command to the traffic signal controller after determining that the target intersection is an intersection within a coordinated arterial road and that the congestion direction at the target intersection is the preset coordinated direction.

[0087] In one possible implementation, in step 202, the traffic signal controller determines multiple traffic lights to be adjusted based on the target intersection and the coordination direction, which also determines the control area of ​​the intersection. In this embodiment, the trunk road to which the target intersection belongs is denoted as the target trunk road. Each trunk road includes multiple consecutive intersections and road segments. The traffic signal controller can determine the traffic lights at the target intersection, the upstream traffic lights of the target intersection on the target trunk road, and the downstream traffic lights of the target intersection as multiple traffic lights to be adjusted in the aforementioned coordination direction. The number of upstream traffic lights can be configured as a first number, and the number of downstream traffic lights can be configured as a second number.

[0088] Optionally, the first quantity can be less than or equal to 1. The second quantity can be less than or equal to 3. For example... Figure 3 As shown, assuming the first quantity is 1, the second quantity is 3, and the target intersection is intersection M, meaning intersection M meets the congestion condition. The aforementioned multiple intersections to be adjusted can include intersection M, intersection P, intersection A, intersection B, and intersection D. Intersection P is the upstream intersection of intersection M in the coordination direction. Intersections A, B, and D are all downstream intersections of intersection M in the coordination direction. In this scenario, the multiple traffic lights to be adjusted include the traffic lights at intersection P, intersection M, intersection A, intersection B, and intersection D in the coordination direction, as follows: Figure 3 As shown in the black square.

[0089] In one possible design, if a first downstream intersection exists among the plurality of traffic lights to be adjusted, then the traffic light for that first downstream intersection is removed from the plurality of traffic lights to be adjusted; that is, the traffic light for that first downstream intersection is not adjusted. Here, the first downstream intersection is the intersection downstream of the target intersection in the coordinated direction, and the length of the road segment between the first downstream intersection and the target intersection is greater than a preset road segment length threshold. Optionally, the preset road segment length threshold can be configured to 500 meters.

[0090] In one possible design, if a second downstream intersection exists among the plurality of traffic lights to be adjusted, the traffic light for that second downstream intersection is removed from the plurality of traffic lights to be adjusted; that is, the traffic light for that second downstream intersection is not adjusted. Here, the second downstream intersection is the intersection downstream of the target intersection in the coordination direction, and the ratio of the traffic flow leaving the coordination direction from the second downstream intersection to the total traffic flow at the second downstream intersection is less than a preset ratio threshold. Optionally, this preset ratio threshold can be configured to 0.1.

[0091] In another possible implementation, in step S202, the traffic signal controller determines multiple traffic lights to be adjusted based on the target intersection and the coordinating direction, which also determines the control intersection range. In this embodiment, the trunk road to which the target intersection belongs is denoted as the target trunk road. Each trunk road includes multiple consecutive intersections and road segments. The traffic signal controller can determine the traffic lights of the target intersection, the upstream and downstream traffic lights of the target intersection on the target trunk road, and the traffic lights of the downstream intersection in the non-coordinating direction as multiple traffic lights to be adjusted in the aforementioned coordinating direction. The number of upstream traffic lights can be configured as a first number, and the number of downstream traffic lights can be configured as a second number. It should be noted that in this embodiment, the traffic lights in the non-coordinating direction of the intersection can refer to traffic lights in any direction that exits the coordinating direction of the intersection.

[0092] Optionally, the first quantity can be less than or equal to 1. The second quantity can be less than or equal to 3. For example... Figure 4 As shown, assuming the first quantity is 1, the second quantity is 3, and the target intersection is intersection M, meaning intersection M meets the congestion condition. The aforementioned intersections to be adjusted can include intersection M, intersection P, intersection A, intersection B, and intersection D. Intersection P is the upstream intersection of intersection M in the coordination direction. Intersections A, B, and D are all downstream intersections of intersection M in the coordination direction. In this scenario, the traffic lights to be adjusted are the traffic lights at intersection P, intersection M, intersection A, intersection B, and intersection D in the coordination direction (e.g., ...). Figure 4 (as shown by the black square in the middle), and the traffic lights at intersection A in the non-coordinated direction, and the traffic lights at intersection B in the non-coordinated direction (as shown by the black square in the middle). Figure 4 (As shown by the white square in the middle). It should be noted that... Figure 4 The traffic lights at intersection A shown can include black squares for coordinating directions and white squares for non-coordinating directions, which are only used to distinguish traffic lights in different directions. In actual application scenarios, the traffic lights for coordinating directions and non-coordinating directions at intersection A are set in the same unit.

[0093] In one possible design, if a first downstream intersection exists among the plurality of traffic lights to be adjusted, then the traffic light for that first downstream intersection is removed from the plurality of traffic lights to be adjusted; that is, the traffic light for that first downstream intersection is not adjusted. Here, the first downstream intersection is the intersection downstream of the target intersection in the coordinated direction, and the length of the road segment between the first downstream intersection and the target intersection is greater than a preset road segment length threshold. Optionally, the preset road segment length threshold can be configured to 500 meters.

[0094] In one possible design, if a second downstream intersection exists among the plurality of traffic lights to be adjusted, the traffic light for that second downstream intersection is removed from the plurality of traffic lights to be adjusted; that is, the traffic light for that second downstream intersection is not adjusted. Here, the second downstream intersection is the intersection downstream of the target intersection in the coordination direction, and the ratio of the traffic flow leaving the coordination direction from the second downstream intersection to the total traffic flow at the second downstream intersection is less than a preset ratio threshold. Optionally, this preset ratio threshold can be configured to 0.1.

[0095] In another possible implementation, in step 202, the traffic signal controller determines multiple traffic lights to be adjusted based on the target intersection and the coordinating direction, which also determines the control area of ​​the intersection. The traffic signal controller can also send the determined multiple traffic lights to be adjusted to the management device. Staff can confirm the control area of ​​the traffic lights that need to be adjusted through the management device. In some examples, the management device can send a first confirmation message to the traffic signal controller, indicating that no modification has been made to the multiple traffic lights to be adjusted identified by the traffic signal controller. In other examples, the management device can send a second confirmation message to the traffic signal controller, indicating that the multiple traffic lights to be adjusted identified by the traffic signal controller have been modified, and the modified multiple traffic lights to be adjusted.

[0096] In one possible design, after receiving multiple modified traffic lights to be adjusted, the traffic signal controller determines whether it includes traffic lights from intersections that do not belong to the target arterial road. If it does include traffic lights from intersections that do not belong to the target arterial road, it determines whether the traffic lights at those intersections belong to intersections on other arterial roads. If so, they are removed from the multiple modified traffic lights to be adjusted.

[0097] Figure 5 An exemplary embodiment illustrates a traffic condition identification and analysis method based on a large traffic model. The method includes the following steps:

[0098] Step S501: Determine whether the target intersection meets the congestion conditions.

[0099] Step S502: If it is determined that the target intersection meets the congestion conditions, then based on the target intersection and the coordination direction, a number of traffic lights to be adjusted are determined.

[0100] Step S503: Determine the release duration of the first signal light in the coordination direction among the plurality of signal lights to be adjusted; and determine the issuance time corresponding to the first signal light, wherein the issuance time represents the time when the release control command is sent to the signal corresponding to the first signal light.

[0101] Step S504: If among the plurality of traffic lights to be adjusted, there is a second traffic light at the downstream intersection of the target intersection that is in a non-coordinated direction, then determine the duration of the second traffic light's extension.

[0102] Step S505: According to a predetermined order, the addition and release control strategy is executed on the plurality of traffic lights to be adjusted.

[0103] Step S506: After determining that the target intersection meets the conditions for relieving congestion, a transition control strategy is executed on the plurality of traffic lights to be adjusted.

[0104] In this embodiment, the implementation process of steps S501, S502, S505, and S506 can be found in the relevant descriptions of steps S201, S202, S203, and S204 in the aforementioned embodiments, and will not be repeated here.

[0105] In this embodiment of the application, in steps S503 and S504, the plurality of traffic lights to be adjusted may include traffic lights at the upstream intersection and the downstream intersection of the target intersection in the coordinating direction. Optionally, the plurality of traffic lights to be adjusted may also include traffic lights at the downstream intersection of the target intersection in the non-coordinating direction. Optionally, the plurality of traffic lights to be adjusted may also include traffic lights at intersections outside the target arterial road, such as traffic lights at intersections where coordinating directions intersect. For ease of distinction, the traffic lights in the coordinating direction among the plurality of traffic lights to be adjusted are designated as the first traffic light, and the traffic lights in the non-coordinating direction are designated as the second traffic light.

[0106] Therefore, the first traffic light can be the traffic light at the target intersection, the traffic light at the upstream intersection of the target intersection in the coordinating direction, and the traffic light at the downstream intersection of the target intersection. The second traffic light can be the traffic light at the downstream intersection of the target intersection in the non-coordinating direction, and the traffic light at the intersection of the coordinating directions.

[0107] For the first traffic light among the plurality of traffic lights to be adjusted, the traffic signal controller can determine the extension duration for each first traffic light and the corresponding issuance time for each first traffic light. The issuance time for each first traffic light represents the time when the traffic signal controller sends the extension control command to the corresponding traffic light. For the second traffic light among the plurality of traffic lights to be adjusted, the traffic signal controller can determine the extension duration for each second traffic light.

[0108] The following describes how traffic signal controllers determine the duration of the first signal light.

[0109] Traffic signal controllers can determine the additional allowance ratio corresponding to the first traffic light. The maximum additional allowance ratio for a traffic light can be determined based on the road grade intersecting the intersection direction with the traffic light. Table 2 shows the correspondence between the road grade intersecting the intersection direction with the traffic light and the maximum additional allowance ratio.

[0110] Table 2

[0111]

[0112] Please combine Figure 6 Taking the determination of the extended duration of a traffic light at intersection A in the coordinating direction as an example, intersection A connects road s1 in the coordinating direction and road s2 intersecting in the coordinating direction. Traffic light A-1 at intersection A in the coordinating direction guides traffic flow into road s1, while traffic light A-2 at intersection A in the non-coordinating direction guides traffic flow into road s2. The extended duration of traffic light A-1 at intersection A in the coordinating direction can be determined based on the road s2 classification. For example, if road s2 is an arterial road, the maximum extended duration of traffic light A-1 is 10%. The traffic signal controller can adjust the extended duration based on the maximum extended duration of traffic light A-1. and pre-configured addition control cycle Determine the duration of the additional signal light A-1. .

[0113] In one possible design, there are multiple roads intersecting the intersection with the traffic light in the coordinated direction. The traffic signal controller can determine the maximum allowable ratio for each of these intersecting roads. Then, it selects the smallest of the determined maximum allowable ratios and sets the maximum allowable ratio for that traffic light.

[0114] Please combine Figure 7Taking the determination of the extended duration of the traffic light at intersection A in the coordinating direction as an example, the traffic signal controller can identify the roads intersecting with intersection A in the coordinating direction. Intersection A connects to road s1 in the coordinating direction, road s2 intersecting with the coordinating direction, and road s3 intersecting with the coordinating direction. Traffic light A-1 at intersection A in the coordinating direction guides traffic flow into road s1; traffic light A-2 at intersection A in the non-coordinating direction guides traffic flow into road s2; and traffic light A-3 at intersection A in the non-coordinating direction guides traffic flow into road s3. The extended duration of traffic light A-1 at intersection A in the coordinating direction can be determined based on the road s2 and road s3 classifications. The traffic signal controller can determine the minimum extended duration of traffic light A-1 based on the maximum extended duration of road s2 and road s3. and pre-configured addition control cycle Determine the duration of the additional signal light A-1. .

[0115] Based on the above description, the traffic signal controller can determine the additional release time of each first signal light in the traffic light to be adjusted. The additional release time of the first signal light represents the amount of time added to the original release time of the first signal light.

[0116] The following describes how traffic signal controllers determine the duration of the second traffic light's extension. Traffic signal controllers can determine the duration of the second traffic light's extension based on a preset extension ratio and extension control cycle. Please refer to... Figure 6 The traffic signal controller can determine the duration of signal light A-2 based on a preset extension ratio and a pre-configured extension control cycle. In this application, the non-coordinated direction at an intersection can refer to the direction of exiting the main road to which the intersection belongs; in other words, the non-coordinated direction at an intersection can refer to the turning direction of exiting the coordinated direction at the intersection. The non-coordinated direction at an intersection can include multiple different directions.

[0117] For multiple traffic lights to be adjusted, the way a traffic signal controller applies the release control strategy to the first traffic light is not exactly the same as the way it applies the release control strategy to the second traffic light.

[0118] For each first traffic light, the traffic signal controller implements an extension control strategy, requiring it to send an extension control command corresponding to the first traffic light's issuance time to the first traffic light's controller. This extension control command instructs the first traffic light's controller to operate according to the extension control cycle and the extension duration corresponding to the first traffic light after the current control cycle ends. This design improves the coordination between the first traffic lights and increases congestion relief efficiency.

[0119] For each second traffic light, the traffic signal controller implements an extension control strategy. After determining the extension duration of the second traffic light, it sends an extension control command corresponding to the second traffic light to the traffic signal controller of the second traffic light. The extension control command corresponding to the second traffic light is used to instruct the traffic signal controller of the second traffic light to work according to the extension control cycle and the extension duration corresponding to the second traffic light after the current control cycle ends.

[0120] The following describes the process by which traffic signal controllers determine the issuance time of the first traffic light.

[0121] The maximum adjustment cycle coefficient kmax is determined based on the maximum distance corresponding to all the first traffic lights.

[0122] Based on the adjustment cycle set, a reference time set corresponding to any first traffic light is determined; wherein, the adjustment cycle set includes multiple adjustment cycle parameters, each adjustment cycle parameter being greater than or equal to a first value, and each adjustment cycle parameter being less than or equal to the maximum adjustment cycle coefficient kmax, and the adjustment cycle parameters being integers; the reference time set corresponding to any first traffic light includes multiple adjustment time parameters, the multiple adjustment time parameters corresponding one-to-one with the multiple adjustment cycle parameters, and each adjustment time parameter being determined based on the corresponding adjustment cycle parameter and the extended duration gn of any first traffic light;

[0123] From the set of reference times corresponding to all first traffic lights, the adjustment period parameter corresponding to the smallest adjustment time parameter is determined as the target adjustment period coefficient k'.

[0124] Based on the pre-acquired starting deviation On of any first traffic light, the starting deviation S1 of the traffic light at the upstream intersection of the target intersection in the coordinated direction, the preset control period TC, and the target adjustment period coefficient k', the initial issuance interval dtn' of any first traffic light is calculated. The initial issuance interval represents the interval between the issuance time of any first traffic light and the issuance time of the traffic light at the upstream intersection of the target intersection in the coordinated direction.

[0125] For ease of understanding, combined Figure 6The following describes several signals to be adjusted. These signals include all first traffic lights at intersections P, M, A, B, and D. The maximum distance between all traffic lights is the distance between the first and last intersections along the coordination direction, such as the distance between intersection P and intersection D. The traffic signal controller can calculate the maximum adjustment period coefficient kmax based on the maximum distance between all first traffic lights, a preset vehicle speed, and a preset coordination period TC. Lmax represents the maximum distance corresponding to all first traffic lights, v represents the preset vehicle speed, and TC represents the preset coordination period for adding and releasing traffic lights.

[0126] Traffic signal controllers can determine the adjustment period set K according to a preset method based on the maximum adjustment period coefficient kmax. The adjustment period set can include multiple adjustment period parameters. For example, The adjustment period parameters in the adjustment period set K are all integers that are greater than or equal to a first value and less than or equal to the maximum adjustment period coefficient kmax. Optionally, the first value can be -1.

[0127] Traffic signal controllers can determine the reference time set corresponding to each first traffic light based on the adjustment cycle set K. For any traffic light n, the reference time set corresponding to traffic light n includes multiple adjustment time parameters, and these multiple adjustment time parameters correspond one-to-one with the multiple adjustment cycle parameters in the adjustment cycle set K. An adjustment time parameter of traffic light n is determined based on the corresponding adjustment cycle parameter.

[0128] Assuming the adjustment cycle set K contains x adjustment cycle parameters, then the reference time set corresponding to traffic light n contains x adjustment time parameters. There is a one-to-one correspondence between the x adjustment cycle parameters and the x adjustment time parameters. Let the i-th adjustment cycle parameter be denoted as ki, and let the x-th adjustment time parameter corresponding to ki in the reference time set of traffic light n be denoted as tn_i. The relationship between an adjustment time parameter of traffic light n and its corresponding adjustment cycle parameter is as follows: Where Ln represents the distance between traffic light n and the first traffic light in the coordinated direction among all the first traffic lights, and is also the distance between the intersection to which traffic light n belongs and the intersection to which the first traffic light in the coordinated direction (denoted as traffic light 1) belongs; v is the preset vehicle speed; On represents the difference between the start time of the first cycle of traffic light n on the day and 0:00; gn represents the non-release duration within the original control cycle of traffic light n, that is, the starting deviation of traffic light n. S1 represents the difference between the start time of the first cycle of traffic light 1 on the day and 0:00, that is, the starting deviation of traffic light 1; g1 represents the non-release duration within the original control cycle of traffic light 1.

[0129] Therefore, it can be seen that the traffic signal controller can calculate the reference time set Tn of the traffic light n. Similarly, traffic signal controllers can calculate the reference time set for each first signal light, namely T1, T2, T3, etc.

[0130] The traffic signal controller can select the smallest adjustment time parameter from the set of reference times corresponding to all first traffic lights, let's assume it's... This refers to the qth adjustment time parameter of traffic light p. The adjustment period parameter corresponding to this adjustment time parameter, i.e., the pth adjustment period parameter kp in the adjustment period set, is determined as the target adjustment period coefficient. For ease of distinction, the target adjustment period coefficient determined by the traffic signal controller is denoted as k'.

[0131] Taking traffic light n as an example, the traffic signal controller can calculate the initial issuance interval dtn' of traffic light n based on the aforementioned starting deviation On of traffic light n, the aforementioned starting deviation S1 of traffic light 1, the preset release control period TC, and the target adjustment period coefficient k'. In this embodiment, the initial issuance interval of traffic light n represents the interval between the issuance time of traffic light n and the issuance time of traffic light 1. The initial issuance interval of traffic light n... .

[0132] Similarly, referring to the foregoing description, the traffic signal controller can calculate the initial interval for each first traffic light. The traffic signal controller can configure the initial interval for traffic light 1 to be 0.

[0133] In one possible implementation, the traffic signal controller can determine the issuance time of other first traffic lights based on the issuance time of traffic light 1 among all first traffic lights and the initial issuance interval of other first traffic lights.

[0134] In another possible implementation, the traffic signal controller can, after determining the initial transmission interval of all first traffic lights, determine whether the initial transmission interval of each first traffic light meets a preset transmission condition. The preset transmission condition can be that the initial transmission interval of the traffic light is greater than 0.

[0135] In one possible scenario, if the initial transmission interval of each first traffic light is greater than 0, it can be determined that the initial transmission interval of all first traffic lights meets the preset transmission conditions. The traffic signal controller can determine the transmission time of each first traffic light based on the initial transmission time of the first traffic light and the output transmission interval of each first traffic light, wherein the initial transmission first traffic light is the traffic light of the upstream intersection of the target intersection in the coordinating direction, i.e., the aforementioned traffic light 1.

[0136] In some examples, traffic signal controllers can send an additional control command corresponding to the initial first signal light to the signal light corresponding to the initial first signal light after determining that the initial issuance interval of each first signal light is greater than 0. The traffic signal controller can record the time when the additional control command corresponding to the initial first signal light is sent to the signal light corresponding to the initial first signal light, as the issuance time of the initial first signal light.

[0137] In other examples, the traffic signal controller can receive an extension command from the management equipment, which can carry the extension time. The traffic signal controller can use the extension time carried in the extension command as the starting time for issuing the first traffic light.

[0138] In another possible scenario, if at least one of the first traffic lights does not meet the preset issuance interval, the traffic signal controller can use the first traffic light with the smallest initial issuance interval as the starting first traffic light. A corrected issuance interval is then calculated for each first traffic light, where the corrected issuance interval is the sum of the absolute values ​​of the initial issuance interval of that first traffic light and the initial issuance interval of the starting first traffic light.

[0139] Assuming that signal light z has the smallest initial transmission interval among all first signal lights, what is the corrected transmission interval for signal light n? The initial time interval for issuing traffic light n Initial time interval between signal light z absolute value The sum, that is Similarly, traffic signal controllers can use this method to determine the correction interval for each first signal light.

[0140] Then, the traffic signal controller can determine the issuance time of each first signal light based on the issuance time of the initial first signal light (which is also the first signal light with the smallest initial issuance interval among all the aforementioned first signal lights) and the corrected issuance interval of each first signal light. The traffic signal controller can configure the corrected issuance interval of signal light z to 0.

[0141] In some examples, the traffic signal controller can, after calculating the corrected release interval for each first signal light, send a release control command corresponding to the initial release of the first signal light to the signal light corresponding to that initial release. The traffic signal controller can record the time when the release control command corresponding to the initial release of the first signal light is sent to the signal light corresponding to that initial release, as the release time of the initial release of the first signal light.

[0142] In other examples, the traffic signal controller can receive an addition command from the management equipment, which can carry the addition time. The traffic signal controller can use the addition time carried by the addition command as the starting time for issuing the first traffic light.

[0143] The method for determining the lower time of each first traffic light provided in this application embodiment can enhance the coordination effect among all first traffic lights and improve the relief or mitigation of congestion in the coordinated direction.

[0144] In the traffic condition identification and analysis method based on a large traffic model provided in any of the above embodiments, the congestion relief condition may include any one of the following:

[0145] Condition R1: The traffic index of the target intersection on the approach road segment in the coordination direction is less than or equal to a preset second index threshold, and the duration is greater than a preset second duration.

[0146] Condition R2: The queue length of the approach lane at the target intersection in the coordination direction is less than a preset length threshold, and the duration is less than the second duration.

[0147] Condition R3: The traffic index of the road segment in the intersecting direction of the target intersection is greater than the preset third index threshold, and its time duration is greater than the preset third duration. The intersecting direction is the direction that has an intersecting relationship with the coordinating direction.

[0148] Condition R4: The queue length of the intersecting direction entrance lanes of the target intersection is greater than the preset length threshold, and the duration is greater than the third duration.

[0149] Condition R5: A bottleneck occurs in the road segment that intersects with the main road to which the target intersection belongs.

[0150] In some examples, traffic signal controllers can determine whether the traffic index of the approach road segment of the target intersection in the coordinating direction meets condition R1 based on internet data. The traffic signal controller can acquire the traffic index of the approach road segment of the target intersection in the coordinating direction in real time. The traffic signal controller can determine whether the traffic index is less than or equal to a preset second index threshold. If the traffic index is less than or equal to the preset second index threshold, the traffic signal controller can determine whether the duration of the traffic index being less than or equal to the second index threshold is greater than a preset second duration. If the traffic index of the target intersection is less than or equal to the second index threshold and the duration is greater than the preset second duration, then the target intersection is determined to meet condition R1, and the target intersection also meets the congestion relief condition. Optionally, the second index threshold and the second duration can be configured according to the actual application scenario. For example, the second index threshold can be configured to 4, and the preset second duration can be configured to 5.

[0151] In other examples, traffic signal controllers can use radar detectors to obtain the queue length of the approach lanes at the target intersection in the coordinating direction. If the queue length is less than or equal to the length threshold corresponding to the target intersection, and the duration for which the queue length is less than or equal to the corresponding length threshold is greater than the aforementioned second duration, then the target intersection is determined to meet condition R2, which is also the condition for the target intersection to relieve congestion.

[0152] In some examples, traffic signal controllers can determine whether the traffic index of the intersecting road segments at the target intersection meets condition R3 based on internet data. The intersecting direction refers to the direction that intersects with the coordinating direction. The traffic signal controller can acquire the traffic index of the intersecting road segments at the target intersection in real time. The traffic signal controller can determine whether the traffic index is greater than a preset third index threshold. If the traffic index is greater than the preset third index threshold, the traffic signal controller can determine whether the duration of the traffic index being greater than the third index threshold is greater than a preset third duration. If the traffic index of the target intersection is greater than the third index threshold and the duration is greater than the preset third duration, then the target intersection is determined to meet condition R3, and the target intersection also meets the congestion relief condition. Optionally, the third index threshold and the third duration can be configured according to the actual application scenario. For example, the third index threshold can be configured to 6, and the preset third duration can be configured to 10.

[0153] In other examples, traffic signal controllers can use radar detectors to obtain the queue length of the approach lanes at the target intersection in the intersecting directions. If the queue length is greater than the length threshold corresponding to the target intersection, and the duration for which the queue length is greater than the corresponding length threshold is greater than the aforementioned third duration, then the target intersection is determined to meet condition R4, which is also the condition for the target intersection to relieve congestion.

[0154] In other examples, traffic signal controllers can use bottleneck detectors to determine whether bottlenecks exist in the intersecting road segments of a target intersection. If a bottleneck exists, the target intersection is determined to meet condition R5, which is also the condition for resolving congestion.

[0155] Based on the traffic condition identification and analysis method based on a large traffic model provided in any of the above embodiments, the traffic signal controller executes an addition / removal control strategy on the plurality of traffic lights to be adjusted, which can execute... Figure 8 The process is shown in the figure. Figure 8 An exemplary transition control strategy is shown, which may include the following steps:

[0156] S801: For any intersection to which a traffic light to be adjusted belongs, determine the large transition control cycle and small transition control cycle of the intersection based on the starting deviation of the operation of the intersection.

[0157] S802, based on the minimum green phase of the intersection and the coordination direction, determine the compression control cycle of the intersection.

[0158] S803, based on the compressed control cycle of the intersection and the default maximum control cycle of the intersection, select a transition control cycle from the large transition control cycle and the small transition control cycle.

[0159] S804, the traffic signal controller that controls all traffic lights at the intersection operates according to the selected transition control cycle.

[0160] For any intersection belonging to one of the multiple traffic lights to be adjusted in the coordinated direction, that is, the intersection to which the first traffic light mentioned above belongs, the traffic signal controller can execute a transition control strategy for the intersections in the target trunk line that are participating in the coordinated addition, according to the operations in steps S801-S804 above.

[0161] Traffic signal controllers can use the time when the target intersection meets the congestion relief conditions as the reference end time Tend. Continuing with intersection A as an example, the traffic signal controller can determine the small transition control period TCe1_n and the large transition control period TCe2_n for intersection A based on the starting deviation OA of the traffic lights at intersection A, the reference end time Tend, and the preset control period TC. Please refer to... Figure 6 The traffic lights at intersection A include traffic lights for coordinating directions and those for non-coordinating directions. The operational start deviation OA of intersection A represents the difference between the start time of the first operating cycle of the traffic lights at intersection A and 0:00. Within the first operating cycle, the difference between the start time of the traffic light in any direction at intersection A being in the green state and 0:00 is the operational start deviation of that direction's traffic light. By providing an example, the difference between the operational start deviation of intersection A and the operational start deviation of any traffic light in any direction at that intersection can be clarified.

[0162] mod(a, b) is a function that calculates the remainder when integer a is divided by integer b. In some examples, the small transition control period TCe1_A of intersection A is TC-mod(Tend-OA, TC). The large transition control period TCe2_A of intersection A is 2×TC-mod(Tend-OA, TC). Here, TC represents the preset release control period, OA is the starting deviation of intersection A, and Tend is the aforementioned reference end release time.

[0163] The traffic signal controller can determine the compressed control period Tmin_A of intersection A based on the minimum green phase of traffic light n and the coordinating direction. The traffic signal controller can pre-store the minimum green phase for each intersection, which is the minimum clearance time for each intersection A within the default control period. For intersection A, assuming that within a default control period, after clearance in the coordinating direction, one or more other directions will be clearanced according to a preset order. When calculating the compressed control period of intersection A, the traffic signal controller can configure the clearance time for these one or more other directions to the minimum green phase of the traffic light at intersection A. The compressed control period Tmin_A of intersection A includes the portion before clearance in the coordinating direction within the default control period, the portion during clearance in the coordinating direction, and the portion during clearance in the one or more other directions according to the minimum green phase.

[0164] The traffic signal controller can select a transition control period from the small transition control period TCe1_A and the large transition control period TCe2_A of intersection A based on the compressed control period Tmin_A of intersection A and the pre-configured default maximum control period Tmax_A of intersection A.

[0165] For example, if the traffic signal controller determines that the small transition control period TCe1_A of intersection A is less than the default maximum control period Tmax_A of intersection A, the traffic signal controller selects the small transition control period TCe1_A of intersection A as the actual transition control period. Alternatively, if the traffic signal controller determines that the compressed control period Tmin_A of intersection A is greater than the large transition control period TCe2_A of intersection A, the traffic signal controller selects the small transition control period TCe1_A of intersection A as the actual transition control period. Otherwise, the traffic signal controller selects the large transition control period TCe2_A of intersection A as the actual transition control period.

[0166] In some examples, if the traffic signal controller selects the large transition control period TCe2_A at intersection A as the actual transition control period, the traffic signal controller will determine a first adjustment duration qt1 that is longer than the additional control period TC, where qt1 = TCe2 - TC. The traffic signal controller can allocate the first adjustment duration based on the proportion of the release duration for the coordinated direction within the default control period of intersection A, and the proportion of the release duration for other directions after the coordinated direction is released.

[0167] For example, at intersection A, within the default control cycle, the traffic flow order in each direction is west, south, and east. Assuming south is the coordinated direction, the traffic signal controller can store the ratio of the southbound traffic flow duration to the eastbound traffic flow duration within the default control cycle, for example, sa1:sa2. The traffic signal controller allocates the first adjustment duration in two parts according to this ratio, where the ratio of the first part to the second part of the first adjustment duration is sa1:sa2.

[0168] The traffic signal controller sums the signal light duration in the coordinated direction at intersection A within the coordinated control cycle with the first part of the first adjustment duration, and determines the signal light duration in the coordinated direction at intersection A within the long transition cycle. The traffic signal controller also sums the signal light duration in other directions at intersection A within the coordinated control cycle (the direction that is released after the coordinated direction within the default control cycle, such as the aforementioned eastward direction) with the second part of the first adjustment duration, and determines the signal light duration in those other directions at intersection A within the long transition cycle.

[0169] In one possible scenario, at intersection A, the direction that is last in the sequence of traffic flow during the default control cycle is the coordinating direction. The traffic signal controller can determine the duration of the traffic light in the coordinating direction during the long transition cycle by summing the duration of the traffic light in the coordinating direction at intersection A within the coordinating control cycle and the first adjustment duration.

[0170] In other examples, if the traffic signal controller selects the small transition control period TCe1_A at intersection A as the actual transition control period, the traffic signal controller will determine a second adjustment duration qt2, which is the difference between the small transition control period TCe1 and the additional control period TC, where qt2 = TCe1 - TC. The traffic signal controller can allocate the second adjustment duration qt2 based on the ratio of the release duration of the coordinated direction within the default control period of intersection A, and the release duration of other directions after the coordinated direction is released. For example, within the default control period of intersection A, the release order of each direction is south, east, and west. Assuming south is the coordinated direction, the traffic signal controller can store the ratio of the release duration of south, east, and west within the default control period, for example, sb1:sb2:sb3. The traffic signal controller allocates the second adjustment duration into three parts according to this ratio, where the ratio of the first part, the second part, and the third part of the second adjustment duration is sb1:sb2:sb3.

[0171] The traffic signal controller determines the difference between the first part of the green light duration and the second adjustment duration of the traffic lights at intersection A in the coordinated direction within the coordinated control cycle, and the second part of the green light duration, as the green light duration (BBT1) of the traffic lights at intersection A in the coordinated direction within the short transition cycle. The traffic signal controller determines the difference between the second part of the green light duration and the second adjustment duration of the traffic lights at intersection A in other directions (such as the aforementioned eastbound direction) within the coordinated control cycle, and the third part of the green light duration and the second adjustment duration of the traffic lights at intersection A in other directions (such as the aforementioned westbound direction) within the coordinated control cycle, and the third part of the green light duration and the second adjustment duration, and the third part of the green light duration, and the third part of the green light duration, and the third part of the green light duration, and the third part of the traffic signal ... within the short transition cycle, the green light duration (BBT3) of the traffic lights at intersection A in other directions.

[0172] In one possible scenario, one or more of the aforementioned release durations BBT1, BBT2, and BBT3 are less than the minimum green phase at intersection A. Assume release duration BBT2 is less than the minimum green phase at intersection A. The traffic signal controller determines, within the coordinated control cycle, the difference (dBBT) between the release duration of the traffic lights at intersection A in other directions (directions that are released after the coordinated direction in the default control cycle, such as the aforementioned eastward direction) and the minimum green phase at intersection A. The traffic signal controller subtracts the second adjustment duration qt2 from the difference (dBBT) to determine the third adjustment duration qt3. The traffic signal controller allocates the third adjustment duration into two parts according to the ratio of the southbound release duration to the westbound release duration within the default control cycle, i.e., sb1:sb3. The ratio of the first part to the second part of the third adjustment duration is sb1:sb3.

[0173] The traffic signal controller updates the difference between the signal light duration in the coordinated direction and the first part of the third adjustment duration at intersection A within the coordinated control cycle to the signal light duration BBT1 in the short transition cycle at intersection A in the coordinated direction. The traffic signal controller also updates the difference between the signal light duration in other directions (such as the aforementioned westbound direction) and the second part of the third adjustment duration at intersection A within the coordinated control cycle to the signal light duration BBT2 in the short transition cycle at intersection A in those other directions.

[0174] The traffic signal controller can refer to the aforementioned order of issuing additional control commands to each first traffic light, and the initial issuance interval (or the modified issuance interval) of each first traffic light, to issue transition control commands to the signal controllers of the intersections to which each first traffic light belongs (including coordinated and non-coordinated directions). The transition control commands instruct the signal controllers of each direction at the intersection to operate according to the release duration of each direction within the transition control cycle after the current control cycle ends, and after a preset number of transition control cycles, operate according to the release duration of each direction within the default control cycle. This ensures that the signal controllers controlling all traffic lights at intersection A operate according to the selected transition control cycle.

[0175] Optionally, the preset number of transition control cycles can be one transition control cycle. After executing the preset number of transition control cycles, each intersection with the first traffic light reverts to the default control cycle.

[0176] For intersections where the traffic lights to be adjusted do not belong to the target arterial road, the traffic signal controller can determine the transition control cycle for these intersections using a smooth transition control method. The duration of the transition control cycle for these intersections is the average of the default control cycle and the additional control cycle for that intersection. Furthermore, the green time for each direction at the intersection is the average of the green time for that direction within the additional control cycle and the green time for that direction within the default control cycle.

[0177] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0178] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0179] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0180] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0181] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A traffic condition identification and analysis method based on a large traffic model, characterized in that, include: Determine whether the target intersection meets the congestion criteria; If the target intersection is determined to meet the congestion conditions, then based on the target intersection and the coordination direction, multiple traffic lights to be adjusted are determined, and the coordination direction is a pre-configured direction; According to a predetermined order, an addition and release control strategy is executed on the plurality of traffic lights to be adjusted; After determining that the target intersection meets the conditions for relieving congestion, a transitional control strategy is executed on the plurality of traffic lights to be adjusted; In the coordinated direction, the traffic lights at the target intersection, the traffic lights at a first number of upstream intersections and a second number of downstream intersections of the target intersection on the target trunk line are identified as the plurality of traffic lights to be adjusted. The target trunk line is the trunk line to which the target intersection belongs, and the target trunk line includes multiple intersections. Alternatively, in the coordinated direction, the traffic lights at the target intersection, the traffic lights at a first number of upstream intersections and a second number of downstream intersections of the target intersection on the target trunk line, and the traffic lights at the downstream intersections in the non-coordinated direction are identified as the plurality of traffic lights to be adjusted. Before implementing the addition / release control strategy for the plurality of traffic lights to be adjusted, the method further includes: The release duration of the first signal light in the coordination direction among the plurality of signal lights to be adjusted is determined; and the issuance time corresponding to the first signal light is determined, wherein the issuance time represents the time when the release control command is sent to the signal corresponding to the first signal light; If there is a second signal light in a non-coordinated direction among the plurality of signal lights to be adjusted, then the duration of the second signal light's placement is determined. The multiple traffic lights to be adjusted implement an addition / release control strategy, including: Based on the issuance time corresponding to the first traffic light, a release control command corresponding to the first traffic light is sent to the signal controller of the first traffic light. The release control command corresponding to the first traffic light is used to instruct the signal controller of the first traffic light to work according to the release control cycle and the release duration corresponding to the first traffic light after the current control cycle ends. If the second signal light is among the plurality of signals to be adjusted, after determining the release duration of the second signal light, a release control command corresponding to the second signal light is sent to the signal controller of the second signal light. The release control command corresponding to the second signal light is used to instruct the signal controller of the second signal light to work according to the release control cycle and the release duration corresponding to the second signal light after the current control cycle ends. Determining the issuance time corresponding to the first traffic light includes: The maximum adjustment cycle coefficient kmax is determined based on the maximum distance corresponding to all the first traffic lights. Based on the adjustment cycle set, a reference time set corresponding to any first traffic light is determined; wherein, the adjustment cycle set includes multiple adjustment cycle parameters, each adjustment cycle parameter being greater than or equal to a first value, and each adjustment cycle parameter being less than or equal to the maximum adjustment cycle coefficient kmax, and the adjustment cycle parameters being integers; the reference time set corresponding to any first traffic light includes multiple adjustment time parameters, the multiple adjustment time parameters corresponding one-to-one with the multiple adjustment cycle parameters, and each adjustment time parameter being determined based on the corresponding adjustment cycle parameter and the non-departure duration gn of any first traffic light; From the set of reference times corresponding to all first traffic lights, the adjustment period parameter corresponding to the smallest adjustment time parameter is determined as the target adjustment period coefficient k'. Based on the pre-acquired starting deviation On of any first traffic light, the starting deviation S1 of the traffic light at the upstream intersection of the target intersection in the coordination direction, the preset control period TC, and the target adjustment period coefficient k', the initial issuance interval dtn' of any first traffic light is calculated. The initial issuance interval represents the interval between the issuance time of any first traffic light and the issuance time of the traffic light at the upstream intersection of the target intersection in the coordination direction. The step of determining the issuance time corresponding to the first traffic light further includes: If the initial issuance interval of all first traffic lights meets the preset issuance conditions, then the issuance time of each first traffic light is determined based on the issuance time of the first traffic light at the start of issuance and the initial issuance interval of each first traffic light. The first traffic light at the start of issuance is the traffic light of the upstream intersection of the target intersection in the coordinated direction. If at least one of the first traffic lights does not meet the preset transmission conditions in its initial transmission interval, the first traffic light with the smallest initial transmission interval among all the first traffic lights is selected as the starting first traffic light, and the corrected transmission interval of any one of the first traffic lights is calculated. The corrected transmission interval of any one of the first traffic lights is the sum of the absolute values ​​of the initial transmission interval of the any one of the first traffic lights and the initial transmission interval of the starting first traffic light. Based on the transmission time of the starting first traffic light and the corrected transmission interval of each first traffic light, the transmission time of each first traffic light is determined.

2. The method as described in claim 1, characterized in that, The implementation of a transition control strategy for the plurality of traffic lights to be adjusted includes: For any intersection to which a traffic light to be adjusted belongs, the large transition control cycle and small transition control cycle of the intersection are determined based on the starting deviation of the operation of the intersection. Based on the minimum green phase of the intersection and the coordination direction, the compression control cycle of the intersection is determined; Based on the compression control cycle of the intersection and the default maximum control cycle of the intersection, a transition control cycle is selected from the large transition control cycle and the small transition control cycle. The traffic signal controllers that control all the traffic lights at the intersection operate according to the selected transition control cycle.

3. The method as described in any one of claims 1-2, characterized in that, The congestion conditions include any one of the following: The traffic index of the target intersection on the entrance road segment in the coordinated direction is greater than a preset first index threshold, and the duration is greater than a preset first duration. The queue length at the entrance lane of the target intersection in the coordinated direction is greater than the length threshold corresponding to the target intersection, and the duration is greater than the preset first duration. Upon receiving a congestion release instruction from the management device, the congestion release instruction indicates that the target intersection is congested in the coordinated direction, and the trunk road to which the target intersection belongs belongs to a preset trunk road set.

4. The method as described in any one of claims 1-2, characterized in that, The congestion relief condition includes any one of the following: The traffic index of the target intersection at the entrance road segment in the coordinated direction is less than or equal to a preset second index threshold, and the duration is greater than a preset second duration. The queue length at the target intersection in the direction of coordination is less than a preset length threshold, and the duration is less than the second duration. The traffic index of the road segment in the intersecting direction of the target intersection is greater than the preset third index threshold, and its time duration is greater than the preset third duration. The intersecting direction is the direction that has an intersecting relationship with the coordinating direction. The queue length of the approach lanes in the intersecting directions of the target intersection is greater than the preset length threshold, and the duration is greater than the third duration. The road sections at the target intersection in the intersecting directions are experiencing bottlenecks.

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