Tunnel vehicle-road cooperative control system based on V2X

Abstract

The invention discloses a tunnel vehicle-road cooperative control system and a working method thereof, and aims to improve the safety, smoothness and energy efficiency of tunnel traffic by using a vehicle-to-everything (V2X) communication technology. The system is composed of a vehicle-mounted unit, a road side unit in a tunnel and a central control unit, and information intercommunication between vehicles, between the vehicles and the road side unit and between the vehicles and the central control unit is achieved. The vehicle-mounted unit collects and transmits vehicle state information, the road side unit detects environment conditions and sends data, and the central control center integrates the information, generates control instructions such as vehicle speed adjustment and traffic management measures through an algorithm and issues the control instructions to a vehicle through the road side unit. The system can deal with normal and emergency conditions, ensure the safety of vehicles in the tunnel, optimize traffic mobility and reduce energy consumption. The method can also adapt to different traffic and tunnel conditions, the stability of traffic flow is kept, and an innovative scheme is provided for solving urban tunnel congestion.

Description

Technical Field

[0001] The present invention relates to vehicle-to-everything (V2X) communication technology, and particularly to a system for interaction and collaborative control between vehicles and roadside facilities in a tunnel environment. Background Art

[0002] With the continuous increase in the number of vehicles and the aggravation of traffic congestion problems, traditional traffic management methods have faced great challenges. In order to improve traffic safety, reduce traffic congestion, and provide a more convenient travel experience, the development of a vehicle-road collaborative system based on V2X technology has become an important research direction. V2X technology refers to various communication methods such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-pedestrian (V2P), vehicle-to-network (V2N), and vehicle-to-cloud platform (V2C) through wireless communication technology. This diversified communication enables vehicles to obtain traffic information in a timely manner and make corresponding responses, thus achieving efficient collaboration between vehicles and between vehicles and infrastructure.

[0003] The tunnel traffic system poses certain challenges to vehicle driving due to its enclosed space and special road environment. In a tunnel, due to limited visibility and road lighting restrictions, drivers are prone to problems such as inattentiveness and driving fatigue. In addition, since vehicles are driving in a narrow tunnel, the occurrence of an accident often leads to more serious consequences. Therefore, the tunnel traffic system requires an efficient management method to ensure traffic safety and smoothness.

[0004] The V2X-based tunnel vehicle-road collaborative control system is a solution proposed to meet the above needs. By using V2X technology, the system can obtain information on vehicles and road infrastructure in real time, analyze and process it, and thus provide valuable support for drivers and traffic management departments. In addition, the system can also combine with the vehicle navigation system and cloud platform to provide drivers with real-time navigation and traffic conditions information. Drivers can obtain information such as the speed limit information of the current tunnel, oncoming traffic, and accident warnings through the display screen or voice prompts, improving driving safety and comfort.

[0005] In summary, the V2X-based tunnel vehicle-road collaborative control system realizes the safe driving of vehicles and the intelligent management of the traffic system through efficient communication between vehicles and between vehicles and road infrastructure, providing an innovative solution for tunnel traffic. The research and application of this system have important practical significance and application prospects. Summary of the Invention

[0006] To solve the above problems, the present invention proposes a tunnel vehicle-road collaborative control system based on V2X, which can accurately judge the traffic state in the tunnel and control vehicle driving, thereby improving the driving safety and traffic flow in the tunnel. The system includes the following components:

[0007] S1: Road-Side Unit (RSU):

[0008] V2X communication module: Responsible for communicating with the V2X communication module on the vehicle side and sending traffic management information, environmental information, etc. to surrounding vehicles. Environmental monitoring device: Includes sensors and monitoring equipment for monitoring the internal environment of the tunnel, such as air quality, visibility, traffic density, etc. Traffic management unit: Based on the collected environmental information and traffic flow information, formulates optimized traffic flow control strategies, such as controlling vehicle speed, adjusting traffic signal status, etc.

[0009] S2: On-Board Unit (OBU):

[0010] V2X communication module: Responsible for V2X communication with other vehicles and the road-side unit, receiving and sending real-time traffic information, safety warning information, etc. Vehicle perception module: Perceives the situation of the vehicle's surrounding environment through sensors (such as cameras, radars, lidars, etc.), including other vehicles, tunnel road conditions, pedestrians, etc. Data processing and decision-making unit: Responsible for receiving and processing data from the V2X communication module and the vehicle perception module, and making corresponding decisions, such as adjusting vehicle speed, changing lanes, etc.

[0011] S3: Centralized Processing and Control Center (CPCC):

[0012] Data processing and analysis unit: Responsible for centrally processing and analyzing the data transmitted from the vehicle side and the road-side unit to achieve more advanced traffic flow control and scheduling functions. Traffic information service unit: Provides real-time traffic information and suggestions to drivers or monitoring personnel, such as traffic status, estimated travel time, etc.

[0013] In the system architecture, the vehicle unit, the road-side unit, and the central processing center are interconnected through a communication network to achieve the transmission and processing of real-time data. The core of the entire system lies in V2X communication technology, which enables real-time communication and data exchange between vehicles and between vehicles and road-side facilities, thereby realizing the functions of the tunnel vehicle-road collaborative control system.

[0014] The various standards and protocols used by the tunnel vehicle-road cooperation control system based on V2X of the present invention, such as IEEE802.11p: also known as wireless traffic system (ITS) communication, which is a standard specifically designed for vehicle-to-vehicle communication and vehicle-to-infrastructure communication. It is based on the 802.11 standard and uses a frequency band of 5.9 GHz, capable of providing low-latency and highly reliable communication, which is very suitable for real-time communication and cooperative control between vehicles. C-V2X (Cellular Vehicle-to-Everything): A V2X communication technology based on cellular networks, which can achieve vehicle-to-vehicle and vehicle-to-infrastructure communication through cellular networks. C-V2X can provide V2X communication services through existing cellular network infrastructure, with good coverage and communication stability. IEEE 802.11a / b / g / n / ac / ax: In addition to V2X-specific communication protocols, the tunnel vehicle-road cooperation control system may also use Wi-Fi standard protocols, such as protocols in the 802.11 series, to achieve data transmission and communication between vehicles and the central control system / server. These communication protocols can work together to provide communication services at different levels and scopes for the tunnel vehicle-road cooperation control system. Through these communication protocols, vehicles can achieve real-time data exchange with other vehicles, roadside units, and the central control system / server, thus realizing real-time traffic management and cooperative control inside the tunnel.

[0015] This invention details how vehicles utilize the information received from the V2X system to adjust their driving strategies. The vehicle control strategy is a key part of the tunnel vehicle-road cooperation control system. It is based on the received traffic information, environmental perception data, and information of other vehicles obtained through V2X communication to determine the driving actions of the vehicle. The following are some common vehicle control strategies:

[0016] S1: Adaptive cruise control: According to the traffic conditions inside the tunnel and the speed of the vehicle in front, adaptive cruise control can automatically adjust the vehicle speed to maintain a safe distance and smoothly follow the speed of the vehicle in front. It can reduce the driver's burden and improve the traffic efficiency and safety of the road.

[0017] S2: Lane departure warning and correction: This strategy uses sensors to detect whether the vehicle deviates from the current lane and issues corresponding warning signals to remind the driver. When necessary, the system can also perform lane correction control to return the vehicle to the safe lane through slight steering adjustments.

[0018] S3: Automatic lane change: Based on sensors and V2X communication, the system can identify the vehicle density and speed in the target lane ahead and perform automatic lane change control according to the traffic flow situation. This can help optimize the vehicle driving path, reduce congestion, and improve the traffic capacity of the road.

[0019] S4: Collision Warning and Automatic Emergency Braking: Based on the vehicle perception module and V2X communication, the system can monitor other vehicles and pedestrians in the tunnel in real time and issue a warning signal when a potential collision threat is detected. If the driver fails to take timely action, the system can also automatically execute emergency braking to avoid collisions or mitigate the consequences of accidents.

[0020] The traffic management strategy of the present invention is an important part of the tunnel vehicle-road collaborative control system, and its goal is to optimize traffic flow, reduce congestion, and improve road safety and efficiency. Through the traffic signal optimization algorithm, combined with the traffic flow and prediction model in the tunnel, the timing and phase of the traffic lights are adjusted to optimize the passing efficiency of vehicles in the tunnel. This can reduce vehicle queuing time, lower the parking waiting time, and improve the road passing capacity. According to the traffic flow and prediction in the tunnel, the lane use strategy is adjusted. For example, according to the change of traffic flow, through dynamic lane control, more lanes are allocated to the main traffic flow direction during peak hours to improve the road passing efficiency. Through traffic monitoring devices and vehicle perception modules, potential traffic congestion areas are monitored and identified in real time, and roadside personnel or emergency vehicles are dispatched in a timely manner for intervention. This can help clear congestion in a timely manner and maintain road smoothness. Based on the traffic monitoring and prediction model, the system can identify potential accident risks and traffic anomalies, and through V2X communication and roadside facilities, issue warnings to drivers in real time or report the situation to the central control system to take corresponding measures to prevent accidents or handle anomalies. Through in-vehicle terminals or roadside displays, real-time traffic information services are provided to drivers, including road conditions, traffic congestion, estimated travel time, etc. This can help drivers make better driving decisions and optimize the travel route.

[0021] The safety functions in the tunnel vehicle-road collaborative control system of the present invention are crucial, aiming to help reduce the occurrence of traffic accidents and protect the safety of drivers and passengers in case of emergencies. Using in-vehicle sensors and V2X communication, the system can monitor the surrounding vehicles and the situation in the tunnel, and issue an alarm to the driver when a potential collision risk is detected. Some systems can even automatically activate emergency braking to avoid collisions. By monitoring the position of the vehicle in the lane, the system can identify whether there is a lane departure behavior. If such a situation is found, the system will issue an alarm to the driver or take measures to assist in correcting the vehicle position. By automatically adjusting the vehicle speed to maintain a safe distance and automatically decelerating or even stopping when necessary, the adaptive cruise control helps reduce the risk of rear-end collisions. Using in-vehicle cameras and image processing technology, the system can identify traffic signs and display information such as speed limit signs and no U-turn signs to the driver, reminding the driver to abide by traffic rules. In case of an accident or other emergency, the system can automatically trigger the emergency call function, send the vehicle's position information to relevant rescue agencies and assist in providing emergency assistance.

[0022] The traffic information service of the present invention plays an important role in the tunnel vehicle-road collaborative control system, aiming to provide timely and accurate traffic condition information to drivers to help them make more informed travel decisions. The system collects and integrates real-time traffic condition information, such as road conditions, congestion situations, traffic accidents, etc., from roadside sensors, in-vehicle devices, and other data sources, and provides drivers with timely updated traffic dynamics. Based on the collected traffic information, the system can provide drivers with the best route planning and navigation services, adjusting the driving route in real time according to the current traffic situation and destination to avoid congested areas and improve traffic efficiency. Through the parking information service provided by the system, drivers can obtain real-time availability of nearby parking spaces, parking fees, and route guidance to available parking spaces, improving parking efficiency. Based on historical data and real-time traffic conditions, the system can predict and warn of future traffic conditions, helping drivers plan their trips in advance and avoid potential future traffic congestion. The system enables vehicles to share real-time traffic information with each other through vehicle-to-vehicle communication and vehicle-road collaborative communication, providing information such as vehicle position, speed, and driving intention to other vehicles, thereby improving traffic safety and efficiency.

[0023] In the tunnel vehicle-road collaborative control system of the present invention, environmental monitoring is one of the crucial functions, which aims to monitor the environmental parameters inside and outside the tunnel in real time and provide relevant information to drivers and system operators to ensure safety and comfort inside the tunnel.

[0024] The air quality monitoring system inside and outside the tunnel can detect the concentrations of pollutants such as carbon dioxide, carbon monoxide, and particulate matter in real time, providing real-time data to ensure that the air quality inside the vehicle meets safety standards. By using visible light cameras and sensors, the visibility conditions inside and outside the tunnel, such as fog, rain, and smoke, are monitored, warning drivers in a timely manner and providing safety suggestions through the system. The changes in temperature and humidity inside and outside the tunnel are monitored to help drivers and system operators understand the climate conditions inside and outside the tunnel and take corresponding countermeasures in a timely manner. According to the changes in light inside and outside the tunnel, the lighting system inside the tunnel is automatically adjusted to ensure good visibility for drivers and pedestrians. A fire and smoke monitoring system is installed inside the tunnel to detect fire and smoke situations in a timely manner and take corresponding fire extinguishing and evacuation measures to ensure safety inside the tunnel.

[0025] In addition, in the tunnel vehicle-road collaborative control system, the scalability of the system refers to the ability to easily add new functions, modules, or components to adapt to future business needs and technological developments. A system with good scalability can be extended without the need for a complete reconstruction or disruption of the entire system structure. To achieve system scalability, modular design and a loosely coupled architecture can be adopted, enabling new functions or modules to be developed, tested, and integrated independently. Additionally, using general-purpose interfaces and standardized protocols also helps the system to be integrated and extended with other systems. The maintainability of the system refers to the degree to which the system is easy to modify, debug, and maintain. A system with good maintainability should have a clear code structure, highly readable code, clear naming conventions, good documentation, and comments, etc. Such a design enables developers and maintenance personnel to more easily understand and modify the code when the system needs to be modified or repaired. At the same time, adopting appropriate development tools and technologies can also improve the maintainability of the system, such as using version control systems, adopting automated testing, and continuous integration, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the principle of the tunnel vehicle-road collaborative control system of the present invention.

[0027] Figure 2 It is a control flowchart of the tunnel vehicle-road collaborative control system of the present invention.

[0028] Figure 3 It is a control logic flowchart of the tunnel vehicle-road collaborative control system of the present invention.

[0029] Wherein: 3 - tunnel space; 1 - on-vehicle unit OBU; 2 - roadside unit RSU; 4 - central processing center CPCC EMBODIMENTS

[0030] The following further details the specific embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention. The following is a more detailed description through specific embodiments: As Figure 1 shown, the present invention provides a tunnel vehicle-road collaborative control system based on V2X, and the system includes: On-vehicle unit 1, the vehicle itself will be equipped with OBU (On-Board Units) and necessary sensors and cameras to facilitate the vehicle to receive instructions sent from the tunnel system, monitor the surrounding environment, and assist in driving safety.

[0031] Roadside Unit 2 installs RSUs (Roadside Units) at key positions inside the tunnel. They serve as communication base stations to ensure the stability of wireless communication and are used to forward V2X messages. These positions will also be equipped with vehicle detection devices, monitoring cameras, environmental monitoring sensors, lighting and signal systems, as well as emergency rescue facilities to monitor traffic conditions in real time, guide vehicle driving, and respond to emergencies.

[0032] Central Processing Center 4, the core of the vehicle-road collaborative control in the tunnel, is the central processing and management system located in the monitoring center. It is responsible for analyzing the data transmitted from various devices inside and outside the tunnel and formulating control strategies based on this data. The data storage and backup system are also indispensable for data analysis and emergency response. The design of the entire system should consider the complete integration and coordination between devices as well as redundant design to ensure the robustness and reliability of the system.

[0033] Central Processing Center 4 maintains contact with Roadside Unit 2 (RSUs) through high-speed connections and communicates with vehicles through dedicated short-range communication (DSRC) or cellular V2X (C-V2X) technology to ensure the ability to collect data, analyze situations, and issue instructions in real time, so as to achieve the goals of the vehicle-road collaborative control system inside the tunnel.

[0034] In the above solution, to ensure the functions and efficiency of the vehicle-road collaborative control system in the tunnel, the communication network is crucial. The network needs to provide high-bandwidth and low-latency communication capabilities, adopt multi-layer architectures, wired and wireless transmission technologies to enhance the stability and reliability of the system. The core network layout needs to consider wireless communication coverage, especially inside the tunnel, and install a sufficient number of Roadside Units 2 (RSUs) to ensure communication with On-Board Unit 1 (OBU). The network also needs redundant design to back up key devices and network paths to cope with single-point failures. Security protection measures are indispensable, encrypting key data to resist external attacks and prevent information leakage. The network design needs to be compatible and scalable to prepare for future technology upgrades and capacity expansions.

[0035] As Figure 2 shown, the present invention provides a control process for a vehicle-road collaborative control system in a tunnel. The process includes: First, when a vehicle enters the tunnel area, the tunnel system exchanges information with the vehicle through V2I communication to obtain relevant data of the vehicle, including information such as vehicle model, speed, and cargo load. Subsequently, through vehicle information detection, the system will analyze and verify various information of the vehicle to ensure that the vehicle's state meets the requirements for tunnel passage.

[0036] After information detection, the system will judge the tunnel requirements: if the vehicle meets the passing requirements, the system will allow it to pass through the tunnel; otherwise, corresponding control measures will be executed. For vehicles that do not meet the requirements, the system may perform speed control, guide the vehicle into a specific lane or require it to enter the waiting area, etc., to ensure the safety and smoothness of the traffic in the tunnel.

[0037] For vehicles passing through the tunnel, the system will conduct data exchange and collaboration. This step includes real-time communication with the vehicle to ensure that the vehicle's status in the tunnel can be monitored in real time and information exchange can be carried out. Based on the data exchange and collaboration, the system can analyze the traffic conditions in the tunnel in real time and draw a conclusion on whether control is needed.

[0038] After analyzing the real-time traffic conditions, the system will make a decision on whether to adjust the control. If it is found that the traffic in the tunnel is abnormal or control measures need to be changed, the system will make corresponding adjustments to the vehicle, which may include adjusting the vehicle's speed, guiding the vehicle into different lanes, etc., to ensure the smoothness and safety of the traffic in the tunnel.

[0039] In addition, the system is also responsible for monitoring and outputting traffic status reports. By monitoring the status of vehicles in the tunnel and outputting traffic status reports, it helps the management department understand the traffic conditions in the tunnel. At the same time, the system needs to issue public information announcements, announcing information such as the traffic conditions and road conditions in the tunnel to remind vehicles and pedestrians to pay attention to safety.

[0040] Finally, the flowchart also includes an emergency response system. Once an emergency occurs, such as a traffic accident, the system will quickly respond according to the real-time situation to ensure the safety and smoothness in the tunnel and assist in the launch of relevant rescue work.

[0041] As Figure 3 shown, the present invention provides a control logic flow of a tunnel vehicle-road collaborative control system, and the process includes: From the start node, the vehicle enters the tunnel detection area, and the equipment in the detection area immediately detects whether there is a vehicle. This process can be completed by sensors such as geomagnetic sensors, radars, and cameras. After the decision node in the flowchart for detecting whether there is a vehicle, it branches into two paths. If the system detects a vehicle, it will proceed to the next step, that is, collect vehicle information. In this link, the system may collect key information such as the vehicle type, license plate, speed, and the driver's behavior pattern. If it is detected that there is no vehicle, it will enter the no-operation node, that is, the system will not make any response and remain in a standby state.

[0042] After the system collects vehicle information, the process continues to the decision node for evaluating traffic conditions. Here, based on the collected information, the system analyzes whether the current traffic conditions require intervention or control. If it is evaluated that traffic conditions need to be manipulated, the process continues to issue traffic control instructions. In this step, the management system may issue various control instructions, such as adjusting traffic lights, speed limits, or initiating evacuation procedures in case of emergencies, to guide vehicles to take corresponding driving behaviors. After execution, the vehicle will enter the stage of receiving and executing control instructions to ensure that the instructions are accurately applied.

[0043] Conversely, if the traffic conditions are currently stable and do not require special intervention, then from the traffic condition evaluation node, the process will turn to maintaining the status quo. In this stage, the management system keeps observing and does not issue additional control signals.

[0044] Whether it is monitoring after issuing instructions or observing while maintaining the status quo, both will flow to monitoring traffic flow and vehicle behavior, which is a continuous process to ensure that any changes can be detected by the system and responded to quickly.

[0045] Finally, the process will reach the decision node for whether to end, which is responsible for determining whether the entire management process needs to be terminated. If it is determined to end, then the process goes to the end, and the system may enter the shutdown or standby mode. If the management still needs to continue, it will return from the new loop to the vehicle entering the tunnel detection area and restart the detection and management loop process.

Claims

1. A tunnel vehicle-road collaborative control system based on V2X, characterized in that, The system includes: S1: Road-Side Unit (RSU): Installed at multiple fixed points in the tunnel, it is used to collect passing vehicle information and tunnel environment data, and perform two-way data communication with the On-Board Unit. Each RSU is equipped with a high-performance wireless communication module, supporting multiple vehicle networking communication standards, such as 802.11p, LTE-V2X, 5G, etc.; S2: On-Board Unit (OBU): Installed on the vehicle, through multi-sensor fusion function, it collects vehicle status information, including vehicle speed, direction, fault information, etc. The OBU can integrate various vehicle sensor information, such as radar, camera, GPS, etc., to improve the accuracy and reliability of data; S3: Centralized Processing and Control Center (CPCC): Receives the data sent by the RSU and the OBU, and has the big data processing ability running on a high-performance server for analysis and processing. The CPCC realizes the prediction, scheduling and optimization of the traffic flow in the tunnel, and can monitor the tunnel traffic status in real time.

2. According to the V2X-based tunnel vehicle-road collaborative control system described in claim 1, the wireless communication module equipped with the RSU supports multiple vehicle networking communication standards, such as 802.11p, LTE-V2X, 5G, etc. These communication standards can ensure reliable and efficient data exchange between the RSU and the vehicle to achieve real-time vehicle-road collaborative control.

3. According to the V2X-based tunnel vehicle-road collaborative control system described in claim 1, the OBU has a multi-sensor fusion function. The OBU can integrate various vehicle sensor information, such as radar, camera, GPS, etc. By fusing the data of multiple sensors, the OBU can provide more accurate and credible vehicle status information, thus providing a more reliable data basis for the CPCC.

4. According to the V2X-based tunnel vehicle-road collaborative control system described in claim 1, the CPCC adopts a high-performance server and has big data processing ability. The CPCC can run complex traffic flow analysis and simulation algorithms, and support the optimized scheduling of tunnel traffic through real-time monitoring and prediction of the tunnel traffic status. The high performance and big data processing ability of the CPCC ensure the efficient processing and rapid response to large-scale data.

5. According to the V2X-based tunnel vehicle-road collaborative control system described in claim 1, an intelligent transportation management platform is integrated. This platform not only provides a user interface for traffic management personnel to monitor the tunnel conditions and adjust the traffic control strategy, but also publishes traffic information to the public, and can perform data interaction and linkage control with other traffic infrastructures at the same time, such as optimizing traffic signal control to improve traffic efficiency and responding to emergencies to assist rescue work.

6. A method of using a V2X-based tunnel vehicle-road collaborative control system includes the following steps: S1: RSU in the tunnel collects traffic flow and environmental data; by setting multiple RSU in the tunnel, it can comprehensively collect information on vehicle passing and environmental data inside the tunnel, such as meteorological conditions, visibility, etc.; S2: The vehicle OBU updates and sends vehicle status data to the RSU in a timely manner; the OBU on the vehicle will collect the status information of the vehicle in real time, including vehicle speed, direction, fault information, etc., and through data exchange with the RSU, transmit this information to the RSU in a timely manner; S3: CPCC receives data from the RSU and OBU, and performs processing and analysis; the Central Processing Center CPCC is the core of the control system, and it receives and processes data from the RSU and OBU. CPCC will analyze the collected data, including prediction of traffic flow, monitoring of traffic status, etc.; S4: CPCC issues instructions to vehicles and roadside units according to the analysis results; based on the analysis results of the data, CPCC will formulate and issue instructions to vehicles and roadside units. These instructions can include speed limits, lane selection suggestions, etc., which are used to optimize the smoothness and safety of tunnel traffic; S5: The optimal control of tunnel traffic is achieved through the cooperation between vehicles and roadside units; the cooperation between vehicles and roadside units is the key to achieving the optimization of tunnel traffic. Through data sharing and instruction execution, vehicles and roadside units can make corresponding adjustments according to the real-time traffic conditions to achieve the optimal control of traffic flow.

7. According to the method described in claim 7, the system can adjust the traveling speed, lane selection, and following distance of vehicles in the tunnel in real time, and make dynamic adjustments according to traffic flow data and environmental conditions to ensure traffic smoothness and safety. At the same time, when an emergency occurs, the system can warn the following vehicles in real time and establish virtual warning signs around the emergency area, and send them to surrounding vehicles through V2X communication technology to guide them to avoid in time and reduce the accident risk.

8. According to the method described in claim 7, CPCC can predict the traffic flow based on real-time and historical traffic data. Based on the prediction results, CPCC can reasonably arrange the traffic flow at the tunnel entrance, for example, by appropriately adjusting signal control to avoid excessive congestion inside the tunnel. This can improve traffic efficiency and reduce traffic jam problems.

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