A T-shaped intersection traffic guidance system and method based on roadside parking lot cooperation

Abstract

This invention relates to the field of intelligent traffic safety control, specifically to a T-junction traffic guidance system and method based on roadside parking lot collaboration. It addresses the problem of insufficient control effectiveness of existing technologies in severe congestion scenarios with limited road space. This invention constructs an integrated collaborative architecture of roadside, parking lot, and vehicle, fusing multi-source data to predict vehicle queue length in real time and dynamically determining traffic guidance conditions based on available parking lot capacity. If the conditions are met, the system sorts and plans the trajectory of target vehicles, utilizing parking lot access resources to implement "passage diversion" and "spatiotemporal displacement." This method effectively expands the physical traffic space at intersections, avoids the risk of deadlock caused by queue overflow, and significantly improves road network resilience and traffic safety in severe congestion scenarios.

Description

Technical Field

[0001] This invention relates to the field of intelligent traffic safety control, specifically to a T-junction traffic guidance system and method based on roadside parking lot cooperation. Background Technology

[0002] With the continuous growth of car ownership and travel demand in my country, urban road congestion is becoming increasingly common. Road intersections, as key nodes for traffic flow convergence and dispersal, have become frequent congestion areas. For T-junctions, which are widespread in the road network, during peak hours, the queue length of vehicles going straight on the main road often increases sharply, leading to a decrease in intersection capacity, increased vehicle delays, and potentially causing serious traffic problems such as queue overflow.

[0003] To alleviate intersection congestion, existing technologies primarily focus on optimizing signal timing schemes to improve intersection efficiency. Furthermore, with the development of vehicle-to-everything (V2X) technology, vehicle-road cooperative control has also achieved good results in improving intersection efficiency and alleviating congestion. Both of these methods share the characteristic of actively controlling and intervening in traffic lights, optimizing signal time resource allocation to improve intersection efficiency. However, when the intersection is already congested, these methods are limited by road space and cannot fully utilize the potential of V2X technology, thus impacting the improvement in intersection efficiency.

[0004] For the aforementioned common T-junctions, especially those located on main roads, roadside parking facilities are often provided. The entrances and exits of these parking lots typically have an upstream location and a downstream location. In theory, in such scenarios, the traffic potential can be maximized through coordinated control of the T-junction and the parking lots, thereby alleviating traffic congestion. However, existing intersection control technologies have not fully considered these specific road environment characteristics and have failed to effectively utilize the spatial layout relationship between the T-junction and the roadside parking lots for joint optimization, thus limiting further improvements in intersection efficiency and effective mitigation of traffic congestion.

[0005] Therefore, there is an urgent need for a new method that can deeply integrate and coordinate the operation of T-junctions and roadside parking resources to overcome the shortcomings of existing technologies. This method can guide vehicles to utilize parking space for diversion or detours in traffic congestion situations, enabling rapid vehicle passage and thus alleviating traffic congestion. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a T-junction traffic guidance system and method based on roadside parking lot cooperation. This system solves the problem that existing T-junction congestion management technologies mainly rely on signal timing optimization and vehicle-road cooperation, but their control effect is insufficient in severe congestion scenarios where road space is limited.

[0007] To achieve the above objectives, this invention proposes a T-junction traffic guidance system based on roadside parking lot cooperation, comprising: an intersection data acquisition and traffic status perception subsystem, an edge cooperative control subsystem, a parking lot control subsystem, and a vehicle guidance subsystem; The edge collaborative control subsystem is communicatively connected to the intersection data acquisition and traffic state perception subsystem, the parking lot control subsystem, and the vehicle guidance subsystem, respectively. The intersection data acquisition and traffic status perception subsystem is used to collect real-time traffic data at T-junctions and send traffic situation information to the edge collaborative control subsystem. The edge collaborative control subsystem receives the traffic situation information and the parking lot available capacity information fed back by the parking lot control subsystem. Based on the traffic situation information and the parking lot available capacity information, it determines whether the preset diversion conditions are met. When the conditions are met, it generates a vehicle passage guidance instruction containing the internal passage of the parking lot and sends the vehicle passage guidance instruction to the vehicle guidance subsystem. The parking lot control subsystem is used to receive the vehicle passage guidance instructions and adjust the passage status of the parking lot entrance and internal passages according to the instructions; The vehicle guidance subsystem is used to receive and issue vehicle passage guidance instructions to the target vehicle.

[0008] The intersection data acquisition and traffic condition perception subsystem includes: The traffic light information acquisition module communicates with the intersection signal controller via a wireless communication interface. The traffic flow detection module is equipped with a radar detector; The traffic state perception microprocessor is connected to the traffic light information acquisition module and the traffic flow detection module, respectively, and is configured to upload the fused traffic situation information to the edge collaborative control subsystem.

[0009] The edge collaborative control subsystem includes: The communication module is connected to the intersection data acquisition and traffic condition perception subsystem, the parking lot control subsystem, and the vehicle guidance subsystem, respectively. An edge collaborative control microprocessor, connected to a communication module, is used to generate vehicle passage guidance information; The storage module, connected to the edge collaborative control microprocessor, is used to store information.

[0010] The parking lot control subsystem includes: The parking lot access status monitoring module is equipped with a geomagnetic detector or a video stream detector, which is configured to collect vehicle traffic data at the parking lot entrances and exits and internal access lanes in real time. The communication module is connected to the parking lot access status detection module, the parking lot information sign, and the edge collaborative control subsystem, respectively. The parking information sign is communicatively connected to the microprocessor of the edge collaborative control subsystem, and is used to receive and display the passage status and guidance instructions of the parking lane; The parking lot entrance and exit control module is equipped with a geomagnetic detector. The geomagnetic detector is communicatively connected to the edge collaborative control subsystem. The parking lot entrance and exit control module is connected to the edge collaborative control subsystem and controls the opening and closing of the parking lot entrance and exit according to the parking lot control command.

[0011] The vehicle-mounted guidance subsystem includes: The positioning module, which communicates with the communication module, is used to collect the vehicle's location information and send the location information to the communication module. The communication module uses wireless communication technology to communicate with the edge collaborative control subsystem and is used to receive information sent by the edge collaborative control subsystem. The voice prompt module is used to generate voice prompts based on the received vehicle traffic guidance information; The guidance information display module is used to display the guidance route on the electronic map based on the received vehicle traffic guidance information.

[0012] The present invention also includes a method for implementing the above-mentioned T-junction traffic guidance system based on roadside parking lot cooperation, specifically including the following steps: S1: Obtain the traffic light status and straight-ahead traffic flow data at the intersection, and calculate and predict the real-time vehicle queue length after multi-source data fusion processing; S2: Obtain parking lot available capacity information, and based on the real-time vehicle queue length, traffic light status and parking lot available capacity information, determine whether the preset traffic guidance conditions are met; S3: If the vehicle traffic guidance conditions are met, calculate the number of target guided vehicles, and sort and plan the driving trajectories of the target vehicles. S4: Generate vehicle passage guidance instructions based on the driving trajectory planning, and send the vehicle passage guidance instructions to the vehicle guidance subsystem to guide the target vehicle through the passage.

[0013] This invention constructs an integrated collaborative architecture of roadside, parking lot, and vehicle, and uses edge computing to dynamically schedule parking lot channel resources to achieve "passage diversion" and "temporal and spatial displacement". This can effectively expand the physical passage space at intersections, avoid the risk of deadlock caused by queue overflow, and significantly improve the resilience and traffic safety of the road network in severe congestion scenarios.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention breaks down the barriers between the independent road network and static traffic facilities in traditional traffic management, enabling dynamic coordination between road and parking resources. By sensing intersection congestion in real time and dynamically allocating parking lane resources, it achieves "passage diversion," effectively alleviating traffic pressure at T-junctions during peak hours and improving the overall road network's resilience.

[0015] This invention constructs a closed-loop guidance mechanism covering the entire chain, from roadside perception and edge decision-making to in-vehicle terminal presentation. It not only provides macro-level route guidance through parking lot signs but also utilizes in-vehicle terminals to push precise voice and visual navigation that integrates electronic maps and real-time traffic conditions to drivers. This achieves "point-to-point" delivery of guidance information, significantly improving drivers' response efficiency to collaborative strategies and the accuracy of their travel routes. Attached Figure Description

[0016] The invention will now be further described with reference to the accompanying drawings.

[0017] Figure 1 This is a system composition block diagram of the present invention; Figure 2 This is a diagram of the intersection data acquisition and traffic condition perception subsystem of the present invention; Figure 3 This is a diagram of the edge collaborative control subsystem of the present invention; Figure 4 This is a diagram of the parking lot control subsystem of the present invention; Figure 5 This is a diagram of the vehicle-mounted guidance subsystem of the present invention; Figure 6 This is a schematic diagram of the guiding method of the present invention; Figure 7 This is a scene diagram of a T-junction and a parking lot according to the present invention; Figure 8 This is for the case of LN2 distribution only. Driving trajectory map; Figure 9 This is only the case of LN1 distribution. Driving trajectory map; Figure 10 It is a parking information sign; Figure 11This is a schematic diagram of the initial vehicle distribution when the number of guiding vehicles is 10. Figure 12 yes Vehicle driving instructions for lane LN1; Figure 13 yes A schematic diagram of the driving trajectory as it approaches the lane change zone; Figure 14 yes Driving instructions after entering lane LN2; Figure 15 yes arrive Driving trajectory map; Figure 16 yes Vehicle driving instructions for lane LN2; Figure 17 This is a diagram illustrating the vehicle's movement as V2 approaches the entrance to the road parking lot access lane; Figure 18 It is V2 that arrived. Driving trajectory map; Figure 19 This is a diagram showing vehicle guidance after 10 vehicles enter the road parking lot access lane. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 As shown, a T-junction traffic guidance system based on roadside parking lot collaboration includes: an intersection data acquisition and traffic status perception subsystem, an edge collaborative control subsystem, a parking lot control subsystem, and a vehicle guidance subsystem.

[0020] Intersection data acquisition and traffic condition perception subsystem, such as Figure 2 As shown, it includes: The traffic light information acquisition module communicates with the intersection signal controller via a wireless communication interface and is configured to directly read traffic light status information from the intersection signal control equipment. This traffic light status information includes at least the current phase (red / green) of the straight-ahead traffic light, the remaining time of the current phase, and the signal cycle length.

[0021] The traffic flow detection module is equipped with a radar-visual detector and is configured with a perception technology based on radar and video fusion. It actively detects and acquires traffic flow parameters in the straight-ahead direction at the intersection, including traffic volume, average vehicle speed, and vehicle dissipation rate (saturation flow rate). By fusing the precise speed and distance measurement capabilities of radar with the image recognition and classification capabilities of video, it detects the traffic flow in the straight-ahead direction.

[0022] The traffic condition perception microprocessor receives and fuses traffic light information from the traffic light information acquisition module and traffic flow data from the traffic flow detection module to obtain vehicle flow, vehicle speed, and traffic density. Based on the detection data, it calculates the predicted queue length and feeds it back to the edge collaborative control subsystem. The fused traffic situation information is then uploaded to the edge collaborative control subsystem in real time via a standard interface.

[0023] Edge collaborative control subsystem such as Figure 3 As shown, it includes: The communication module is responsible for acquiring information sent by the intersection data acquisition and traffic status perception subsystem, acquiring vehicle location information from the vehicle guidance subsystem, obtaining parking information from the parking control subsystem, transmitting vehicle passage guidance information to the vehicle guidance subsystem, and transmitting control commands to the parking lot from the edge collaborative control subsystem.

[0024] The edge collaborative control microprocessor is primarily responsible for acquiring parking lot information, intersection vehicle information, intersection status information, vehicle location information, and the number of vehicles entering and exiting parking lot entrances and exits using the communication module. Based on this information, it performs vehicle traffic guidance judgments and generates vehicle traffic guidance information. The vehicle traffic guidance judgment determines whether vehicle traffic guidance conditions are met based on preset thresholds, including constraints such as parking lot lane capacity and available lane capacity, and calculates the number of vehicles to guide. Vehicle traffic guidance information generation is mainly based on the results from the vehicle traffic guidance judgment module. The vehicle traffic guidance information includes voice information, electronic maps of the intersection and parking lot, electronic maps of traffic guidance information, and parking lot information signage. This information is displayed to the driver via the in-vehicle guidance subsystem and voice prompts, and is also displayed to the driver via parking lot information signs. Furthermore, it generates parking lot control commands, namely, opening and closing the parking lot entrance and exit.

[0025] The storage module mainly stores the acquired and transmitted information, including intersection data, traffic status data, parking lot data, vehicle data, road data, vehicle traffic guidance judgments, and other vehicle traffic guidance information.

[0026] Parking control subsystem such as Figure 4 As shown, it includes: The parking lot access lane status monitoring module is used to collect real-time vehicle traffic information at parking lot entrances and exits and within the lanes. Based on geomagnetic detectors or video stream detectors, the module counts the number of vehicles passing and stopping per unit time, detects vehicle throughput and congestion in the parking lot lanes, and obtains the lane's operational status: unobstructed or congested. In an unobstructed state, vehicle throughput is normal with no congestion; in a congested state, vehicle dwell time exceeds a set threshold or lane occupancy is high, indicating a congestion trend. When the module detects that a vehicle's continuous stopping time in the lane exceeds a preset threshold (e.g., 30 seconds) or the lane throughput drops to zero, it is considered an abnormal state. The system immediately stops generating new vehicle guidance instructions and displays "Lane abnormal, please proceed straight" on the parking lot information sign to prevent vehicles from entering the parking lot. This mechanism effectively handles extreme situations such as accidents within the parking lot, preventing vehicles from continuing to enter and ensuring the safety and reliability of the system operation.

[0027] The communication module is responsible for transmitting information from the parking lane status detection module of the parking control subsystem to the parking information sign, and for transmitting information with the edge collaborative control subsystem. Specifically, it transmits parking lane status information and parking lane capacity information to the edge collaborative control subsystem, and receives vehicle passage guidance information and parking control commands from the edge control subsystem, namely the opening and closing of the parking entrance and exit.

[0028] Parking information signs, serving as public information output terminals for drivers, are used to display the real-time traffic status of parking lanes and provide guidance instructions. The information is transmitted wirelessly via a microprocessor from the edge collaborative control subsystem, including whether the lane is clear or congested, and suggested information (right turn / straight ahead).

[0029] The parking lot entrance and exit control module deploys geomagnetic detectors to detect the number of vehicles at the entrance and exit, sends the vehicle count information to the edge collaborative control subsystem, and is responsible for opening and closing the parking lot entrance and exit according to the parking lot control instructions from the edge collaborative control subsystem.

[0030] Vehicle guidance subsystem such as Figure 5 As shown, it includes: The positioning module's main function is to collect the vehicle's location information during its journey and then transmit this information to the communication module.

[0031] The communication module employs wireless communication technology to receive voice information, intersection and parking lot electronic maps, traffic guidance information electronic maps, parking lot information signs, road congestion information, parking lot lane status, and vehicle traffic guidance information such as whether passage is recommended, all from the edge collaborative control subsystem. It maintains real-time connectivity with the edge collaborative control subsystem, receiving turning commands (right turn / straight / yield, etc.). After receiving the data, the module transmits it to the guidance information display module. Furthermore, it transmits the vehicle location information from the onboard guidance subsystem's positioning module to the edge collaborative control subsystem.

[0032] The voice prompt module presents guidance information to the driver via voice, ensuring effective information perception. Guidance information is displayed on the in-vehicle screen, and voice guidance commands are played through the in-vehicle audio system.

[0033] The guidance information display module is responsible for presenting the vehicle traffic guidance information of the edge collaborative control subsystem in the form of an electronic map. The module uses an electronic map interface as a carrier to display electronic maps of intersections and parking lots, as well as traffic guidance electronic maps on the vehicle terminal, so that drivers can intuitively understand the vehicle traffic guidance path and the road parking passage path.

[0034] The intersection and parking lot electronic map is used to display the geometric layout information of intersections, road structures, road parking lots, and road parking lot access lanes; the traffic guidance information electronic map is based on the basic electronic map and overlays traffic guidance elements generated by the system, including road numbers, vehicle trajectory planning elements, and road parking lot access lane ground markings, etc., to intuitively indicate the current vehicle's traffic guidance path.

[0035] This application also includes a method for implementing the above-mentioned T-junction traffic guidance system based on roadside parking cooperation, which specifically includes the following steps, the flowchart of which is shown below. Figure 6 As shown.

[0036] 1. Data Acquisition and Status Awareness The intersection data acquisition and traffic condition perception subsystem communicates with the intersection signal controller via the signal light information acquisition module to obtain the real-time light color and remaining time for the straight-ahead phase. Subsequently, the traffic flow detection module uses sensors (radar detectors) to collect traffic flow, average vehicle speed, and queue length in the straight-ahead direction. Afterward, the microprocessor performs preliminary data processing to calculate the real-time queue length. Finally, the microprocessor of the intersection data acquisition and traffic condition perception subsystem is responsible for transmitting multi-source data (including signal light status, traffic flow data, and parking lot status) to the edge collaborative control subsystem.

[0037] Based on real-time monitoring of the current queue length, the queue length for a short period is estimated. The basic principle is that, within the prediction period, the change in queue length is primarily determined by the difference between vehicle inflow and outflow. When the traffic light is red, vehicle passage is restricted, outflow approaches zero, while inflow continues to accumulate, causing the queue length to exhibit an approximately linear growth trend. Based on the above assumptions, the following recursive formula is used to predict the vehicle queue length: ; in, The current queue length (m) is obtained from the results of the roadside radar detector. This indicates the inflow rate (vehicles / s) during the red light period, updated in real time by the vehicle arrival rate statistics from the detectors; This indicates the prediction time step, which takes the remaining red light time of the current signal and is used to estimate the potential cumulative queue growth before the red light ends. It represents the equivalent length of a single vehicle in a queue (m / vehicle), used to characterize the length of road occupied by vehicles when they are stationary or queuing at low speed.

[0038] 2. Vehicle traffic guidance and judgment The microprocessor of the edge collaborative control subsystem receives fused data from the intersection data acquisition and traffic state perception subsystem and makes vehicle passage guidance decisions based on the prediction results. Ultimately, vehicle passage guidance must simultaneously meet the following three conditions: (1) The length of the vehicle queue exceeds the congestion length threshold.

[0039] (2) The traffic light is red and the remaining time of the red light is greater than the estimated time for the queue to dissipate (where the vehicle dissipation rate is obtained in real time by the traffic flow detection module), meaning that the existing queue of vehicles cannot be completely dissipated within the current red light cycle.

[0040] (3) The available capacity of the road parking lot passage is >0.

[0041] The time required for the queue to clear refers to the time required for the vehicles currently in the queue to cross the stop line at a saturation flow rate after the green light turns on. The formula is as follows: ; in, This indicates the current predicted queue length (m); This represents the equivalent length of a single vehicle in the queue (m / vehicle). This represents the vehicle dissipation rate (vehicles / s), which is the number of vehicles that can pass through the stop line per unit time under saturated flow rate. It is obtained in real time by the traffic flow detection module.

[0042] The congestion length threshold is determined by the maximum number of vehicles that can be queued within the detection area and the equivalent length occupied by a single vehicle, as shown in the following formula: ; in, This represents the maximum number of vehicles that can be queued simultaneously within the detector's coverage area.

[0043] Road parking lot access capacity calculation: Let the effective length of the access road to the parking lot be... The equivalent length occupied by a single vehicle is The maximum number of vehicles that a parking lane can accommodate while queuing is defined as: ; in, This represents the geometric length of the channel and is a static parameter.

[0044] Calculation of the number of vehicles passing through the road parking lot: Number of vehicles in the passage This indicates the number of vehicles in the parking lot lane at the current moment, which can be calculated in real time from the vehicle counts at the entrance and exit of the turnstile lane: ; in, and These represent the time intervals. The number of vehicles entering and leaving the lane.

[0045] Calculation of available capacity for road parking access lanes: Based on the above-mentioned channel geometric capacity and real-time occupancy, the available capacity of the parking lot channel is defined as: ; in, This indicates the number of vehicles that the lane can still safely accommodate at the current moment.

[0046] when When the value is >0, the channel status is determined to be unobstructed.

[0047] Vehicle traffic guidance and judgment: Furthermore, a formula for determining vehicle traffic guidance can be obtained.

[0048] ; Where S represents the traffic light status (RED / GREEN / YELLOW). Indicates the predicted queue length (m); This represents the congestion length threshold (m), with a value of 120m. Indicates the available capacity of the passage (vehicles); When G=1, the system generates a vehicle passage guidance instruction and enters the stage of calculating the number of guided vehicles.

[0049] 3. Guiding scheme calculation The parking lot control subsystem uses its parking lot information to calculate the passage quota. Furthermore, the communication module of the parking lot control subsystem receives vehicle passage guidance information from the edge collaborative control subsystem to calculate the number of guided vehicles.

[0050] Number of guided vehicles Determined according to the following relationship: ; in, This indicates the number of vehicles detected by the radar detector in the target lane. Indicates the available capacity of the channel (vehicles).

[0051] This invention is based on Figure 7 The design is based on a scenario commonly encountered in real-world applications. Specifically, the scenario includes a T-junction and a parking lot. The parking lot is located on the right side of the south entrance road of the T-junction, with one entrance and one exit, both equipped with turnstiles, and approximately 50 parking spaces. Vehicles enter the parking lot through the entrance, proceed through the parking lot access road to the exit, and exit in sequence. The parking lot entrance is on the south side of the intersection, and the exit is on the north side.

[0052] This T-shaped signalized intersection consists of a north-south arterial road and an east-west side road. The arterial road is a two-way road. The southbound approach has a middle lane and the rightmost lane for through traffic, and the leftmost lane for left turns and U-turns. The northbound approach has a middle lane and the leftmost lane for through traffic, and the rightmost lane is a dedicated right-turn lane. Vehicles on the side road are only permitted to merge into the arterial road traffic flow by turning left or right. Pedestrian crossings are provided in all directions of the intersection for pedestrians to cross the street under traffic signal control.

[0053] The parking lot entrance is located on the south side of the intersection. The system determines the triggering conditions for guidance by detecting queue length and the remaining time of the red light. When the entrance is too close to the stop line, the queue length is unlikely to reach the congestion threshold, and guidance will not be activated, ensuring that it is only used when detours have a time advantage.

[0054] Based on the aforementioned number of guided vehicles, the system sorts through straight-going vehicles, plans their trajectories, generates guidance information, and executes guidance to divert right-turn traffic in congested T-junction scenarios. The specific steps are as follows: (1) Vehicle passage sequence After receiving the real-time locations of vehicles in the two straight lanes (middle lane LN1 and right lane LN2) from the vehicle guidance subsystem, the system assigns the lane numbers and vehicle numbers as follows: The middle lane (Lane 1) is designated LN1: vehicle number is , The right lane (Lane 2) is designated LN2: vehicle number is , First priority: sorted by distance from the parking lot entrance (vehicles closer to the entrance have priority).

[0055] The system guides all vehicles based first on their distance from the parking lot entrance. Sort by size from smallest to largest. Whoever is closer to the parking lot entrance goes first; this is an absolute priority principle, and it is implemented first.

[0056] Second priority: When the distance is close (or the same), the LN2 lane takes precedence.

[0057] If the distance difference between two vehicles waiting to be guided and the parking lot entrance is ≤5m, they are considered to be close in distance, and the "LN2 lane vehicle priority" sorting rule is applied. If the distance difference is >5m, they are still sorted according to the first priority (from closest to farthest).

[0058] Let M be the number of vehicles currently being guided, and V be the number of vehicles in the middle lane LN1. The vehicles in this lane are represented as follows: The vehicle located in the right lane LN2 is indicated as The parentheses This indicates the distance between the corresponding vehicle and the parking lot entrance.

[0059] Based on the calculated number of guided vehicles: Vehicle deployment, assuming M vehicles (denoted as M, ... The initial vehicle distribution is as follows: Middle lane LN1: ; Right lane LN2 ; The complete set of all vehicles can be obtained as follows: ; in: .

[0060] Set an entrance reference coordinate point at the parking lot entrance. Its coordinates in the local road coordinate system are: ; any of the vehicles The position coordinates are ; The system calculates the distance from the vehicle to the entrance based on the vehicle's coordinates and the entrance's coordinates. Using Euclidean distance: ; Within each lane, vehicles are numbered from closest to furthest from the parking lot entrance. ; Based on the sorting rules (distance priority, LN2 priority), the passage order sequence for M vehicles is defined as follows: .

[0061] (2) Vehicle trajectory planning ① Definition of trajectory planning parameters and trajectory elements To achieve unified trajectory planning for vehicles in the sorted sequence, the system defines the following trajectory planning parameters in the road coordinate system to describe the complete driving trajectory of a vehicle from its current position to the exit of the road parking lot access lane.

[0062] The lane change interval is set as: x∈[25m,40m]; This interval represents the longitudinal range within which a vehicle is permitted to perform a lateral lane change. This parameter is only enabled when a vehicle needs to change from the middle lane LN1 to the right lane LN2; when the vehicle is initially in LN2, this parameter is not involved in trajectory generation.

[0063] Within the lane-changing section, the vehicle's lateral trajectory can be represented as a function: y(x): LN1→LN2, x∈[25,40]; This function describes a lane change from lane LN1 to lane LN2 during longitudinal travel.

[0064] The entrance to the road parking lot access lane is set as follows: =5 m This indicates that the vehicle begins to transition from a straight-ahead road position to the parking lot access lane at the current location, and completes the trajectory connection for turning right into the lane.

[0065] Case 1 (LN2 distribution only): You should proceed straight along the right-hand LN2 lane and enter the entrance to the road parking lot access lane. Upon reaching the entrance... At this time, turn right into the road parking lot access lane and follow the road markings to the exit, following the driving trajectory as shown below. Figure 8 As shown.

[0066] In maintaining and Under the premise of maintaining a safe distance, proceed straight along LN2, and... After entering the passage, follow the same trajectory. Turn right at the intersection to enter the road parking lot access lane, and follow the road markings to the exit.

[0067] Other vehicles Repeat the above driving trajectory until all M vehicles have passed through the road parking lot passage.

[0068] Case 2 (LN1 distribution only): When all vehicles in the sorted sequence are distributed in the middle lane LN1, the system plans a driving trajectory for each vehicle that includes the lane-changing process.

[0069] The vehicle should proceed straight along LN1. After entering the lane change interval x∈[25m,40m], it should follow the lateral trajectory function. After completing the lane change from LN1 to LN2, the vehicle's trajectory will be the same as that of the vehicle in LN2. The vehicle will continue straight along LN2 until it reaches the entrance of the road parking lot access lane. Turn right into the road parking lot access lane and follow the road markings to the exit. Driving trajectory as follows Figure 9 As shown.

[0070] In satisfying and Under the premise of safe distance constraints, drive along LN1 and complete the lane change operation within the same lane change section, then follow the same... Use the same method to enter the road parking lot access lane.

[0071] Case 3 (mixed distribution of LN1 and LN2): The passage sequence of M guiding vehicles is obtained: ,in This represents the k-th vehicle that is guided to enter the parking area. When... When vehicles are simultaneously distributed in both lanes LN1 and LN2, the system plans differentiated driving trajectories for them based on their initial lane positions.

[0072] For a vehicle initially located at LN2, its trajectory is as follows: travel in a straight line along the current lane to the entrance of the road parking lot access lane, and then... Turn right at the intersection into the road parking lot access lane, and then follow the ground markings to the exit.

[0073] For a vehicle initially located at LN1, its trajectory leads to the exit. In the mixed distribution scenario, vehicles in the sequence execute the trajectory planning described above sequentially. For example, a vehicle traveling straight along LN1, upon reaching the lane change zone, completes a lane change operation to LN2 according to the lateral trajectory function y(x), then continues along LN2, turns right at the entrance to the road parking lot access lane, and follows the ground markings to the exit. In the mixed distribution scenario, vehicles in the sequence execute the trajectory planning described above sequentially.

[0074] 4. Guiding Information Generation Guidance information includes voice messages, electronic maps of intersections and parking lots, electronic maps of traffic guidance information, and parking information signs.

[0075] (1) Voice information Voice communication is the primary means of interaction between the system and the driver, conveying real-time traffic information and guidance to the driver through the in-vehicle terminal.

[0076] When the straight-going vehicle is located at LN1 Straight-through vehicles When approaching the roadside parking area, a voice prompt will say, "Vehicles can use the roadside parking lane to pass through the current intersection; please continue straight." As you approach the lane change zone, a voice prompt will appear: "Approaching the lane change zone, please prepare to turn right into lane LN2 ahead." After entering lane LN2, the voice prompt will say, "Please continue straight and you are about to reach the entrance to the road parking access lane. Please prepare to turn right into the road parking access lane." arrive The voice prompt says, "You have arrived at the entrance to the road parking lot access lane. Please turn right to enter the road parking lot access lane." After completing the right turn and entering the road parking access lane, a voice prompt will say, "You have entered the road parking access lane. Please exit the parking lot in an orderly manner according to the ground markings." The voice prompt will then end.

[0077] When the straight-going vehicle is located at LN2 Straight-through vehicles When approaching the roadside parking area, a voice prompt will say, "Vehicles can use the roadside parking lane to pass through the current intersection; please continue straight." As you approach the entrance to the road parking access lane, a voice prompt will say, "Please continue straight ahead. You are about to reach the entrance to the road parking access lane. Please prepare to turn right into the road parking access lane." arrive The voice prompt says, "You have arrived at the entrance to the road parking lot access lane. Please turn right to enter the road parking lot access lane." After completing the right turn and entering the road parking access lane, the voice prompt "You have entered the road parking access lane. Please exit the parking lot in an orderly manner according to the ground markings" will end.

[0078] (2) Electronic map of intersections and parking lots This is used to display the geometric layout information of intersections, road structures, parking lots, and on-street parking access lanes. It includes intersection configurations (zebra crossings, stop lines, traffic light positions), lane positions, on-street parking lot locations, and on-street parking lot access lane entrances.

[0079] (3) Electronic map of traffic guidance information The traffic guidance information electronic map is based on a basic electronic map, overlaying traffic guidance elements generated by the system, including road numbers, vehicle trajectory planning elements, and ground markings for road parking and access lanes, to intuitively indicate the current vehicle's traffic guidance path.

[0080] The displayed elements include the current lane position (LN1 / LN2), green arrow indicating the vehicle's direction of travel, green arrow indicating a lane change, lane change trajectory, lane change section location, and entrance to the road parking lot access lane. The road parking lot access lane entrance features a green arrow sign for turning right, a right-turn trajectory sign for turning right at the entrance, and ground markings for the road parking lot access lane, all displayed in green.

[0081] (4) Parking information signs The parking information sign displays the following: If the road is congested but the parking lot access lanes are clear and meet the vehicle traffic guidance conditions, it will display "You can turn right into the parking lot access lanes." If the road parking lot access lane status monitoring module detects that a vehicle has been stopped for an extended period (more than 30 seconds) or the lane throughput rate has dropped to zero, the system determines that the parking lot access lane is in an abnormal state and immediately stops guiding vehicles to pass. Simultaneously, the parking information sign will display "Parking lot access lanes are congested, please proceed straight" to prevent vehicles from entering the parking lot. The display content for both scenarios is as follows: Figure 10 As shown.

[0082] 5. Vehicle traffic guidance After vehicle passage prioritization, trajectory planning, and guidance information generation are completed, the system enters the vehicle passage guidance phase. Assume the passage priority sequence for M vehicles is as follows: The system will process them sequentially. Provide traffic guidance. For example, the system generates corresponding traffic guidance based on the lane the vehicle is in. Specifically, The location includes either LN1 or LN2, and corresponding vehicle traffic guidance strategies are implemented based on these two scenarios; subsequent vehicles (k=2, 3, ..., M) according to The driving route guidance is complete. For vehicles located at LN1, the following applies to situation 1: The LN1 vehicle passage guidance path will be followed sequentially, and the same applies to vehicles located in LN2.

[0083] Scenario 1: Located in LN2 When the vehicle is in lane LN2, a voice prompt will say, "The vehicle can use the road parking access lane to pass through the current intersection. Please continue straight." The vehicle's positioning module will send the vehicle's lane location information, and the electronic map will simultaneously display a green arrow indicating straight ahead and the location of the road parking access lane entrance ahead. The green arrow indicates that you should continue straight, and two dashed lines indicate the location of the road parking access lane entrance. At this time, the vehicle should continue straight.

[0084] when As you approach the entrance to the road parking access lane, a voice prompt will say, "Please continue straight ahead. You are about to reach the entrance to the road parking access lane. Please prepare to turn right into the road parking access lane." At this time, the electronic map will simultaneously display the location of the road parking access lane entrance ahead and the green arrow indicating the right turn at the road parking access lane entrance.

[0085] when arrive The system issues a right-turn guidance instruction to the vehicle. A voice prompt reads, "You have arrived at the entrance to the road parking lot access lane. Please turn right to enter the road parking lot access lane." At this time, the electronic map simultaneously displays the guidance route. Follow the existing right-turn route at the entrance to make a right turn, enter the parking lot's internal passageway, continue along the passageway, and exit the parking lot in an orderly manner according to the road markings to complete this guidance.

[0086] exist Before completing the right turn, all other vehicles should continue to follow in lane LN2. Following vehicles Continue driving straight in lane LN2 and follow the vehicle in front. When the system detects that the vehicle is driving straight... After completing the right turn and entering the road parking access lane, a voice prompt will be given. "You have entered the parking lot access lane. Please exit the parking lot in an orderly manner according to the ground markings." After completing the right turn... repeat The vehicle will then exit the parking lot and complete the guidance process.

[0087] Scenario 2: Located in LN1 The vehicle is in lane LN1. At this time, the voice prompt says, "The vehicle can use the road parking passage to pass through the current intersection. Please continue straight." The electronic map of traffic guidance information simultaneously displays the green arrow for going straight, the green arrow for turning right into the lane change section, the lane change section sign, and the sign for the entrance to the road parking passage ahead. The vehicle continues to drive in a straight line.

[0088] when As the vehicle approaches the lane change zone, a voice prompt will appear: "Approaching the lane change zone, please prepare to turn right into lane LN2 ahead." Simultaneously, the electronic map displaying the right-turn sign for entering the lane change zone will be shown. The system will then guide the vehicle to complete the right turn into the lane change zone.

[0089] when After entering the LN2 lane, a voice prompt will say, "Please continue straight and you are about to reach the entrance to the road parking access lane. Please prepare to turn right into the road parking access lane." At the same time, the traffic guidance information on the electronic map will display the entrance to the road parking access lane ahead and use a green arrow to indicate the right turn path. At this time, the vehicle is about to reach the entrance to the road parking access lane.

[0090] when arrive The system issues a right-turn guidance instruction to the vehicle. A voice prompt reads, "You have arrived at the entrance to the road parking lot access lane. Please turn right to enter the road parking lot access lane." Simultaneously, the electronic map displays the guidance route. Follow the right-turn trajectory at the entrance to make a right turn, enter the parking lot's internal passageway, continue driving along the passageway, and exit the parking lot in an orderly manner according to the road markings to complete this guidance.

[0091] exist Before completing the right turn, all other vehicles should continue to follow in lane LN2. Following vehicles Continue driving straight in lane LN2 and follow the vehicle in front. When the system detects that the vehicle is driving straight... After completing the right turn and entering the road parking access lane, a voice prompt will be given. "You have entered the parking lot access lane. Please exit the parking lot in an orderly manner according to the ground markings." After completing the right turn. repeat The vehicle will then exit the parking lot and complete the guidance process.

[0092] 6. Specific Implementation Cases Based on the calculated number of guided vehicles: Vehicle deployment such as Figure 11 As shown, assume there are ten vehicles (denoted as...). The initial vehicle distribution is as follows: Center Lane : ; Right Lane : ; Based on the above rules, first sort by distance. Note that... It is the closest and ranks first. and Next, and so on, handling possible close-proximity parallel situations, ultimately yielding the guiding vehicle sorting sequence: , , , , , , , , , .

[0093] (1) Vehicle traffic guidance The vehicle is in lane LN1. At this time, a voice prompt appears: "Vehicles can use the road parking access lane to pass through the current intersection. Please continue straight." The electronic map simultaneously displays green arrows indicating straight ahead, green arrows indicating a right turn to enter the lane change zone, lane change zone markers, and the location of the road parking access lane entrance ahead. Figure 12 As shown; at this time, the vehicle continues to travel in a straight line.

[0094] when As you approach the lane change zone, a voice prompt will say, "Approaching the lane change zone, please prepare to turn right into lane LN2 ahead." Simultaneously, the electronic map displaying traffic guidance information will show the right-turn sign for entering the lane change zone. Figure 13 As shown. At this point, the system guides the vehicle to complete the right turn and enter the lane change zone.

[0095] when After entering lane LN2, a voice prompt will say, "Please continue straight and you are about to reach the entrance to the road parking access lane. Please prepare to turn right into the road parking access lane." Simultaneously, the traffic guidance information panel displays the entrance to the road parking access lane on the electronic map and guides you to the right turn with a green arrow. Figure 14 As shown; the vehicle is about to reach the entrance of the road parking lot access lane.

[0096] when arrive The system issues a right-turn guidance instruction to the vehicle. A voice prompt reads, "You have arrived at the entrance to the road parking lot access lane. Please turn right to enter the road parking lot access lane." At this time, the electronic map simultaneously displays the guidance route. Follow the right-turn trajectory from the entrance to enter the parking lot's internal passageway. Continue driving along the passageway and exit the parking lot in an orderly manner according to the road markings to complete this guidance process. Figure 15 As shown. When the system detects After completing the right turn and entering the road parking access lane, a voice prompt will be given. "You have entered the road parking lot access lane. Please exit the parking lot in an orderly manner according to the ground markings." (2) Vehicle traffic guidance The vehicle is in lane LN2. At this time, a voice prompt appears: "The vehicle can use the road parking access lane to pass through the current intersection. Please continue straight." The vehicle's positioning module sends the vehicle's lane location information, and the electronic map simultaneously displays a green arrow indicating straight ahead and the location of the road parking access lane entrance. A green arrow indicates maintaining a straight line, and two dashed lines indicate the location of the road parking access lane entrance. Figure 16 As shown; at this time, the vehicle continues to travel in a straight line.

[0097] As V2 approaches the entrance to the road parking access lane, a voice prompt will say, "Please continue straight and you are about to reach the entrance to the road parking access lane. Please prepare to turn right into the road parking access lane." At this time, the electronic map will simultaneously display the location of the road parking access lane entrance and the green right-turn arrow indicator. Figure 17 As shown.

[0098] When V2 reaches xturn, the system issues a right-turn entry guidance instruction to the vehicle. The voice prompt reads, "You have arrived at the entrance to the road parking lot access lane. Please turn right to enter the road parking lot access lane." At this time, the electronic map simultaneously displays the guidance route. V2 executes the right-turn operation according to the existing right-turn trajectory at the entrance, enters the parking lot access lane, continues to drive along the access lane, and exits the parking lot in an orderly manner according to the road markings, completing this guidance. Figure 18 As shown. When the system detects that V2 has completed its right turn and entered the road parking lot access lane, it will give V2 a voice prompt: "You have entered the road parking lot access lane. Please exit the parking lot in an orderly manner according to the ground markings." (3) Vehicle traffic guidance Following vehicles located in lane LN2 The driving process is as follows The driving process, and following the vehicle in front. When driving, when the system detects After completing the right turn and entering the road parking access lane, repeat The vehicle will then exit the parking lot and complete the guidance process.

[0099] Following vehicles in lane LN1 The driving process is as follows The driving process, and following the vehicle in front. When driving, when the system detects After completing the right turn and entering the road parking access lane, repeat The vehicle will then exit the parking lot and complete the guidance process.

[0100] (4) The vehicle exits After the guidance is completed, vehicles will exit the parking lot in an orderly manner according to the ground markings of the parking lot access lane. Simultaneously, a voice announcement will be made: "You have entered the parking lot access lane. Please exit the parking lot in an orderly manner according to the ground markings." Figure 19 As shown.

[0101] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A T-junction traffic guidance system based on roadside parking lot collaboration, characterized in that, include: The system includes an intersection data acquisition and traffic condition perception subsystem, an edge collaborative control subsystem, a parking lot control subsystem, and a vehicle guidance subsystem. The edge collaborative control subsystem is communicatively connected to the intersection data acquisition and traffic state perception subsystem, the parking lot control subsystem, and the vehicle guidance subsystem, respectively. The intersection data acquisition and traffic status perception subsystem is used to collect real-time traffic data at T-junctions and send traffic situation information to the edge collaborative control subsystem. The edge collaborative control subsystem receives the traffic situation information and the parking lot available capacity information fed back by the parking lot control subsystem. Based on the traffic situation information and the parking lot available capacity information, it determines whether the preset diversion conditions are met. When the conditions are met, it generates a vehicle passage guidance instruction containing the internal passage of the parking lot and sends the vehicle passage guidance instruction to the vehicle guidance subsystem. The parking lot control subsystem is used to receive the vehicle passage guidance instructions and adjust the passage status of the parking lot entrance and internal passages according to the instructions; The vehicle guidance subsystem is used to receive and issue vehicle passage guidance instructions to the target vehicle.

2. The T-junction traffic guidance system based on roadside parking lot collaboration according to claim 1, characterized in that... The intersection data acquisition and traffic condition perception subsystem includes: The traffic light information acquisition module communicates with the intersection signal controller via a wireless communication interface. The traffic flow detection module is equipped with a radar detector; The traffic state perception microprocessor is connected to the traffic light information acquisition module and the traffic flow detection module, respectively, and is configured to upload the fused traffic situation information to the edge collaborative control subsystem.

3. A T-junction traffic guidance system based on roadside parking lot coordination according to claim 1, characterized in that... The edge collaborative control subsystem includes: The communication module is connected to the intersection data acquisition and traffic condition perception subsystem, the parking lot control subsystem, and the vehicle guidance subsystem, respectively. An edge collaborative control microprocessor, connected to a communication module, is used to generate vehicle passage guidance information; The storage module, connected to the edge collaborative control microprocessor, is used to store information.

4. A T-junction traffic guidance system based on roadside parking lot coordination according to claim 1, characterized in that... The parking lot control subsystem includes: The parking lot access status monitoring module is equipped with a geomagnetic detector or a video stream detector, which is configured to collect vehicle traffic data at the parking lot entrances and exits and internal access lanes in real time. The communication module is connected to the parking lot access status detection module, the parking lot information sign, and the edge collaborative control subsystem, respectively. The parking information sign is communicatively connected to the microprocessor of the edge collaborative control subsystem, and is used to receive and display the passage status and guidance instructions of the parking lane; The parking lot entrance and exit control module is equipped with a geomagnetic detector. The geomagnetic detector is communicatively connected to the edge collaborative control subsystem. The parking lot entrance and exit control module is connected to the edge collaborative control subsystem and controls the opening and closing of the parking lot entrance and exit according to the parking lot control command.

5. A T-junction traffic guidance system based on roadside parking lot coordination according to claim 1, characterized in that... The vehicle-mounted guidance subsystem includes: The positioning module, which communicates with the communication module, is used to collect the vehicle's location information and send the location information to the communication module. The communication module uses wireless communication technology to communicate with the edge collaborative control subsystem and is used to receive information sent by the edge collaborative control subsystem. The voice prompt module is used to generate voice prompts based on the received vehicle traffic guidance information; The guidance information display module is used to display the guidance route on the electronic map based on the received vehicle traffic guidance information.

6. A method for a T-junction traffic guidance system based on roadside parking lot cooperation as described in any one of claims 1-5, characterized in that, The specific steps include the following: S1: Obtain the traffic light status and straight-ahead traffic flow data at the intersection, and calculate and predict the real-time vehicle queue length after multi-source data fusion processing; S2: Obtain parking lot available capacity information, and based on the real-time vehicle queue length, traffic light status and parking lot available capacity information, determine whether the preset traffic guidance conditions are met; S3: If the vehicle traffic guidance conditions are met, calculate the number of target guided vehicles, and sort and plan the driving trajectories of the target vehicles. S4: Generate vehicle passage guidance instructions based on the driving trajectory planning, and send the vehicle passage guidance instructions to the vehicle guidance subsystem to guide the target vehicle through the passage.

7. A method for a T-junction traffic guidance system based on roadside parking lot coordination according to claim 6, characterized in that... The preset access guidance conditions include: (1) The length of the vehicle queue exceeds the congestion length threshold; (2) The traffic light is red, and the remaining time of the red light is greater than the estimated time for the queue to dissipate; (3) The available capacity of the road parking lot passage is greater than 0.

8. A method for a T-junction traffic guidance system based on roadside parking lot coordination according to claim 6, characterized in that... The sorting of the target vehicles specifically includes the following steps: (1) Obtain the vehicle set of the middle lane LN1 Join the vehicles in the right lane LN2 And calculate the distance between each target vehicle and the parking lot entrance. ; (2) Arrange all target vehicles according to distance The sequences are initially sorted from smallest to largest to generate an initial sequence. (3) Perform traversal correction on the initial sequence: If two adjacent vehicles to be guided in the sequence are located in the middle lane LN1 and the right lane LN2 respectively, and the absolute value of the difference in the longitudinal distance between the two vehicles is less than or equal to 5 meters, then the position of the vehicle located in the right lane LN2 in the sequence is adjusted to be in front of the vehicle located in the middle lane LN1. (4) The corrected sequence is used as the final vehicle sorting result.

9. A method for a T-junction traffic guidance system based on roadside parking lot coordination according to claim 6, characterized in that... The vehicle traffic guidance instructions carry guidance data including voice information, electronic maps of intersections and parking lots, electronic maps of traffic guidance information, and parking lot information signs.

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