Entrance and exit ramp traffic organization method and system based on traffic flow characteristics

Abstract

The invention discloses an entrance and exit ramp traffic organization method and system based on traffic flow characteristics, and relates to the field of traffic organization, and the method comprises the steps: collecting traffic flow data and passing time data of all entrance and exit ramps in a target traffic area; calculating a congestion index of each entrance / exit ramp according to the traffic flow data and the passing time data; calculating a pressure index of each entrance / exit ramp according to the congestion index, the traffic capacity of the entrance / exit ramp and the total length of the ramp; dividing each entrance / exit ramp into a conventional ramp and a control ramp according to the pressure index; compiling a ramp design scheme for each conventional ramp and each control ramp, wherein the ramp design scheme comprises a conventional lane line layout and a gradient virtual and solid line layout; and integrating each ramp design scheme into a regional overall design scheme. By implementing the method, the road passing efficiency of the entrance and exit ramps can be improved.

Description

Technical Field

[0001] The present application relates to the field of traffic organization, and in particular to an entrance and exit ramp traffic organization method and system based on traffic flow characteristics. Background Art

[0002] With the continuous advancement of urbanization and the continuous growth of motor vehicle ownership, the pressure on urban road traffic is increasing. As an important part of urban transportation, elevated expressways serve as the "aorta" of urban transportation, and their traffic efficiency directly affects urban economic development and the quality of residents' travel.

[0003] In the related technology, conventional lane division and lane marking setting methods can be adopted, and only basic guide arrows and lane lines are set in the ramp area. Vehicles can freely choose the driving lane under the premise of complying with traffic regulations.

[0004] However, as traffic volume continues to rise, traditional traffic organization methods are difficult to adapt to new traffic needs. Especially in ramp areas, due to the lack of refined traffic organization design, vehicles have a large number of disorderly lane changes during merging and diverging, which reduces road traffic efficiency. Summary of the invention

[0005] The present application provides an entrance and exit ramp traffic organization method and system based on traffic flow characteristics, which are used to improve the road traffic efficiency of the entrance and exit ramps.

[0006] In the first aspect, the present application provides an entrance and exit ramp traffic organization method based on traffic flow characteristics, which is applied to the entrance and exit ramp traffic organization system, and the method includes: collecting vehicle flow data and travel time data of all entrance and exit ramps in the target traffic area; calculating the congestion index of each entrance and exit ramp based on the vehicle flow data and the travel time data; calculating the pressure index of each entrance and exit ramp based on the congestion index, the traffic capacity of the entrance and exit ramp and the total length of the ramp; dividing each entrance and exit ramp into a conventional ramp and a controlled ramp according to the pressure index; preparing a ramp design plan for each conventional ramp and the controlled ramp, the ramp design plan including a conventional lane line layout and a gradient virtual and real line layout; integrating each ramp design plan into an overall regional design plan.

[0007] By adopting the above technical solution, by collecting the traffic flow data and travel time data of all entrance and exit ramps in the target traffic area, the traffic conditions of the ramps can be fully understood, and the congestion index can be calculated based on these data. The pressure index is then derived by combining the traffic capacity and the total length of the ramp, thereby accurately dividing conventional ramps and controlled ramps, and compiling design plans including specific lane line layouts for different types of ramps. Finally, they are integrated into the overall design plan for the region, which can make traffic organization more in line with actual needs, improve overall traffic operation efficiency, reduce traffic congestion and chaos, and improve traffic safety.

[0008] In combination with some embodiments of the first aspect, in some embodiments, the step of calculating the pressure index of each entrance and exit ramp based on the congestion index, the capacity of the entrance and exit ramps and the total length of the ramps specifically includes: calculating the ratio of the actual traffic volume of each entrance and exit ramp to the designed traffic capacity based on the vehicle flow data to obtain the traffic capacity utilization rate; calculating the ratio of the actual travel time of each entrance and exit ramp to the ideal travel time based on the travel time data to obtain the time delay rate; taking the product of the capacity utilization rate and the time delay rate as the congestion index; and calculating the pressure index based on the relationship between the congestion index, the total length of the ramp and the designed traffic capacity.

[0009] By adopting the above technical solution, the capacity utilization rate is calculated based on the traffic flow data, reflecting the intensity of ramp use from the flow dimension; the time delay rate is calculated based on the travel time data to reflect the travel efficiency. The product of the two is used as the congestion index, which comprehensively considers the use and efficiency of the ramp. The pressure index is calculated based on the relationship between the congestion index, the total length of the ramp and the designed traffic capacity, which fully considers the physical characteristics and traffic operation status of the ramp, and can more accurately evaluate the ramp bearing pressure, which is helpful for implementing differentiated management for ramps with different pressure levels.

[0010] In combination with some embodiments of the first aspect, in some embodiments, the step of preparing a ramp design plan for each of the conventional ramp and the control ramp specifically includes: setting a conventional lane line on the main lane of the conventional ramp, the conventional lane line including a combination of solid lines and dashed lines with uniform starting and ending points; setting stepped dashed and dashed lines on the control ramp, the stepped dashed and dashed lines including a first dashed and dashed line combination between the first lane and the second lane, and a second dashed and dashed line combination between the third lane and the fourth lane, the first dashed and dashed line combination and the second dashed and dashed line combination maintaining a preset front and rear distance.

[0011] By adopting the above technical solution, a conventional lane line with a combination of solid and dotted lines with uniform starting and ending points is set on the main lane of the conventional ramp, and the prohibited and allowed areas for lane change are clearly defined, which is convenient for drivers to identify and standardize the vehicle's driving trajectory. Stepped virtual and real lines are set on the control ramp, and vehicles are guided to change lanes in an orderly manner by setting a combination of virtual and real lines between different lane groups and maintaining a preset front and rear distance. This layout method decomposes the lane change process according to the characteristics of high traffic pressure on the control ramp, reduces vehicle lane change conflicts, and improves lane change safety.

[0012] In combination with some embodiments of the first aspect, in some embodiments, a method for determining a preset front-to-rear distance specifically includes: obtaining a design vehicle speed and lane width of a target road section; calculating a safe driving time required for a vehicle to complete a single lane change based on the design vehicle speed; calculating a minimum safe distance between a first virtual and real line combination and a second virtual and real line combination based on the design vehicle speed and the safe driving time; calculating a lane change trajectory length based on the lane width; comparing the minimum safe distance with the lane change trajectory length, and using the maximum value of the minimum safe distance and the lane change trajectory length as a preset front-to-rear distance between the first virtual and real line combination and the second virtual and real line combination.

[0013] By adopting the above technical solution, the design speed and lane width of the target road section are obtained to provide basic data for subsequent calculations. The safe driving time required for the vehicle to complete a single lane change is calculated based on the design speed, and then the minimum safe distance between the first virtual and real line combination and the second virtual and real line combination is calculated in combination with the design speed, taking into account the impact of vehicle speed on the lane change safety distance. The lane change trajectory length is calculated based on the lane width, and the minimum safe distance is compared with the lane change trajectory length, and the maximum value is taken as the preset front and rear distance, which fully takes into account the space requirements and safety requirements of the lane change operation.

[0014] In combination with some embodiments of the first aspect, in some embodiments, after the step of integrating each of the ramp design schemes into an overall regional design scheme, the method further includes: determining a setting position of a variable information sign in the overall regional design scheme; planning an installation section of an LED display screen according to the gradient virtual and real line layout, the section being located at a preset distance in front of the starting point of each group of virtual and real line combinations, and the LED display screen being used to prompt the driver when to change lanes.

[0015] By adopting the above technical solution, the location of the variable information sign is determined in the overall regional design plan, the control section is reasonably divided along the ramp direction, and the specific installation location is selected based on the sight distance, spacing, power supply and communication conditions, etc., so that the variable information sign can accurately release real-time traffic information and management instructions to the driver at the appropriate location, enhance the driver's understanding of the ramp traffic status, lane change information, exit direction, etc., and make driving decisions in advance. The LED display installation section is planned according to the gradient virtual and real line layout, located at a preset distance before the starting point of the virtual and real line combination, which can promptly remind the driver of the lane change opportunity at the key position, further standardize vehicle driving behavior, reduce driver decision-making errors, improve the orderliness and smoothness of ramp traffic flow, and reduce the risk of traffic accidents.

[0016] In combination with some embodiments of the first aspect, in some embodiments, after the step of integrating each ramp design plan into a regional overall design plan, the method also includes: obtaining traffic flow data and traffic status data of each conventional ramp; calculating the peak congestion index based on the traffic flow data and the traffic status data; when the peak congestion index of a conventional ramp exceeds a preset congestion threshold, generating a ramp reconstruction suggestion.

[0017] By adopting the above technical solutions, traffic flow data and traffic status data of each conventional ramp can be obtained, and the daily traffic operation of conventional ramps can be fully understood. The peak congestion index is calculated based on these data, which can accurately evaluate the congestion level of conventional ramps during periods of concentrated traffic demand. When the peak congestion index exceeds the preset congestion threshold, a ramp reconstruction suggestion is generated. By analyzing the geometric characteristics of the ramp and the traffic operation characteristics, a targeted reconstruction plan is formulated, such as increasing the number of lanes, adjusting the lane width, etc., which helps to timely discover problems with conventional ramps and optimize and improve them to adapt to changes in traffic flow.

[0018] In combination with some embodiments of the first aspect, in some embodiments, after the step of integrating each ramp design plan into a regional overall design plan, the method further includes: sending the regional overall design plan to a target client.

[0019] By adopting the above-mentioned technical solution, the overall regional design plan will be sent to the target client, providing strong support for the implementation of the traffic organization plan and ensuring the orderly progress of traffic improvement work.

[0020] In a second aspect, an embodiment of the present application provides an entrance and exit ramp traffic organization system, which entrance and exit ramp traffic organization system includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the entrance and exit ramp traffic organization system to execute the method described in the first aspect and any possible implementation method of the first aspect.

[0021] In a third aspect, an embodiment of the present application provides a computer program product comprising instructions. When the above-mentioned computer program product is run on an entrance and exit ramp traffic organization system, the above-mentioned entrance and exit ramp traffic organization system executes the method described in the first aspect and any possible implementation method of the first aspect.

[0022] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium comprising instructions. When the instructions are executed on an entrance and exit ramp traffic organization system, the entrance and exit ramp traffic organization system executes the method described in the first aspect and any possible implementation method of the first aspect.

[0023] It can be understood that the entrance and exit ramp traffic organization system provided in the second aspect, the computer program product provided in the third aspect, and the computer storage medium provided in the fourth aspect are all used to execute the method provided in the embodiment of the present application. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, and will not be repeated here.

[0024] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. This application can fully grasp the traffic conditions of the ramps by collecting the traffic flow data and travel time data of all entrance and exit ramps in the target traffic area, calculate the congestion index based on these data, and then derive the pressure index by combining the traffic capacity and the total length of the ramp, so as to accurately divide the conventional ramps and control ramps, and compile design plans including specific lane line layouts for different types of ramps, and finally integrate them into the overall design plan for the region, so as to make the traffic organization more in line with actual needs, improve the overall traffic operation efficiency, reduce traffic congestion and chaos, and improve traffic safety.

[0025] 2. This application sets regular lane lines with a combination of solid and dashed lines with uniform starting and ending points on the main lanes of regular ramps, clarifies the prohibited and allowed areas for lane changes, facilitates driver identification, and regulates vehicle driving trajectories. Stepped dashed and dashed lines are set on the control ramps, and dashed and dashed line combinations are set between different lane groups while maintaining a preset front-to-rear distance to guide vehicles to change lanes in an orderly manner. This layout method decomposes the lane change process based on the characteristics of high traffic pressure on the control ramps, reduces vehicle lane change conflicts, and improves lane change safety.

[0026] 3. This application obtains the design speed and lane width of the target road section to provide basic data for subsequent calculations. The safe driving time required for the vehicle to complete a single lane change is calculated based on the design speed, and then the minimum safe distance between the first virtual and real line combination and the second virtual and real line combination is calculated based on the design speed, taking into account the impact of vehicle speed on the safe distance for lane changes. The lane change trajectory length is calculated based on the lane width, and the minimum safe distance is compared with the lane change trajectory length, and the maximum value is taken as the preset front and rear distance, which fully takes into account the space requirements and safety requirements of the lane change operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a scene diagram of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application; Figure 2 It is a flow chart of an entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application; Figure 3 is another flow chart of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application; Figure 4 It is a scene design diagram of the entrance and exit ramp traffic organization method based on traffic flow characteristics in the embodiment of the present application; Figure 5 It is another scenario design diagram of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application; Figure 6 It is a schematic diagram of the structure of a physical device of the entrance and exit ramp traffic organization system in the embodiment of the present application. DETAILED DESCRIPTION

[0028] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification of the present application, the singular expressions "one", "a kind of", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear indication to the contrary in the context. It should also be understood that the term "and / or" used in the present application refers to any or all possible combinations comprising one or more of the listed items.

[0029] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0030] For ease of understanding, the application scenarios of the embodiments of the present application are introduced below.

[0031] In the overpass area where Suzhou Zhonghuan Road and Donghuan Road meet, there are serious congestion during the morning and evening rush hours every day. Taking a typical weekday morning rush hour in October 2023 as an example, during the period of 7:30-9:00, the average speed in the area was only 15km / h, which was 65% lower than usual. Through traffic monitoring, it was found that congestion was mainly caused by two types of behaviors: first, within 500 meters of the off-ramp, a large number of vehicles suddenly and continuously changed lanes from the innermost lane to the outermost lane, causing all three lanes to be disturbed by the lane change; second, at the on-ramp, the merging vehicles were forced to merge into the main line without sufficient acceleration, and tended to change lanes quickly to the innermost lane. These two types of behaviors forced the main line traffic to slow down frequently, resulting in a serpentine convoy effect, and the traffic flow quickly changed from free flow to a stop-and-go state. Statistics from the traffic police department show that there were 87 rear-end collisions in the area in the first three quarters of 2023, of which 70% were related to lane change behavior. This situation seriously affects the function of the elevated expressway as the main artery of urban traffic.

[0032] At present, the interchange area adopts the conventional traffic organization method: a warning sign is set up before and after the ramp, indicating information such as "500 meters ahead exit" and "Merge ahead"; the road surface is a standard white dotted line, which is changed to a solid line within 100 meters before and after the ramp. However, this solution has obvious shortcomings: first, the driver cannot accurately judge where to start changing lanes, resulting in scattered and disordered lane changes; second, the standard white markings are poorly recognizable under different weather and light conditions; third, there is a lack of progressive lane change guidance, and vehicles are prone to "rushing" lane changes; fourth, there are no differentiated management measures for different lanes, and long-distance straight traffic is mixed with short-distance in and out traffic. These problems have led to a continuous decline in traffic flow quality, and the peak traffic capacity is only about 60% of the design value.

[0033] After adopting the application plan, the interchange area was systematically renovated: first, the ramp was divided into control ramps based on traffic flow data; then, a stepped dashed line was set to decompose the lane change process from the innermost to the outermost into two sections, each of which was 70 meters long, and a 50-meter stable driving interval was maintained between the two sections; the marking line was alternating between yellow solid lines and white dashed lines to enhance recognition; at the same time, LED display screens were set at various key points to prompt information such as "Please change lanes in the dashed area". In the first month after the renovation, the average speed of the area during peak hours increased to 35km / h, and traffic accidents decreased by 47% year-on-year. In particular, the speed of the innermost lane remained above 55km / h, realizing the fast channel function.

[0034] like Figure 1 As shown, it is a scenario diagram of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application.

[0035] exist Figure 1 The traffic conditions of the down-ramp and up-ramp of the elevated expressway. The down-ramp diagram (part a) shows that when approaching the down-ramp, a large number of vehicles cross multiple lanes in disorder and continuously change lanes to the outermost lane ③, seriously interfering with the normal passage of upstream motor vehicles, easily causing rear-end collisions, causing traffic congestion and safety hazards. The up-ramp diagram (part b) shows that some vehicles merge directly into or continuously change lanes into the innermost lane ① without accelerating, which also interferes with upstream vehicles, disrupts traffic order, increases the risk of accidents, and exacerbates traffic congestion during peak hours, affecting residents' commuting.

[0036] For ease of understanding, the following describes the process of the method provided by this implementation in combination with the above scenario. Figure 2 , which is a flow chart of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application.

[0037] S201, collecting traffic flow data and travel time data of all entrance and exit ramps in the target traffic area.

[0038] The target traffic area refers to the specific road section that needs to be optimized for traffic organization, including the main line and all its associated entrance and exit ramps. The entrance and exit ramps refer to the conversion channels connecting the main line and the ground road, including two types: entrance ramps and exit ramps. Traffic flow data refers to the number of vehicles passing through the ramp per unit time, measured in vehicles per hour. The travel time data refers to the actual travel time required for a vehicle to pass the entire ramp, measured in seconds.

[0039] During the operation of the traffic system, it is necessary to collect the operating status data of each ramp in real time to provide data support for subsequent analysis and optimization. Specifically, vehicle detectors are deployed at the entrance and exit sections of the ramp to collect information such as the time and speed of passing vehicles; at the same time, video monitoring equipment is used to monitor the operating status of traffic in real time and record the vehicle passing time; all collected data is transmitted to the traffic management center through the communication network for storage and processing.

[0040] In some embodiments, data collection can be achieved in a variety of ways: Optionally, induction coil detectors are installed at the entrance and exit of the ramp to record the time, speed and other parameters of the passing vehicles in real time, and the data is summarized every 5 minutes and uploaded to the system database; Optionally, cameras are deployed in the ramp area to identify the vehicle type and calculate the travel time through video image processing technology, and record and warn of abnormal situations. It is understandable that other detection equipment or methods can also be used to achieve data collection, which is not limited here.

[0041] S202: Calculate the congestion index of each entrance and exit ramp according to the vehicle flow data and the travel time data.

[0042] Among them, the congestion index is a comprehensive indicator to measure the traffic status of roads, with a value range of 0-1. The larger the value, the more serious the congestion. The traffic volume data reflects the intensity of ramp usage, and the travel time data reflects the traffic efficiency. The two together determine the congestion level of the ramp. The ramp congestion status directly affects the efficiency of main line traffic operation.

[0043] The system needs to calculate the congestion level of each ramp based on the collected real-time data. Specifically, the traffic flow data is first converted into the standard vehicle equivalent number to eliminate the impact of different vehicle models; then the ratio of actual travel time to ideal travel time is calculated to obtain the time delay rate; finally, the indicators of the two dimensions of flow and time are weighted to obtain a comprehensive congestion index.

[0044] In some embodiments, the congestion index calculation can be implemented in a variety of ways: optionally, the flow saturation calculation method is used, and the ratio of the measured flow to the designed traffic capacity is used as the congestion index, and when the ratio exceeds 0.85, it is determined to be a congested state; optionally, the speed method is used, and the ratio of the actual average speed to the designed speed is used as the congestion index, and different judgment thresholds are set according to the road grade. It is understandable that other calculation methods can also be used to obtain the congestion index, which is not limited here.

[0045] S203: Calculate the pressure index of each entrance and exit ramp according to the congestion index, the traffic capacity of the entrance and exit ramps, and the total length of the ramps.

[0046] Among them, the pressure index refers to a quantitative evaluation index that comprehensively reflects the bearing pressure of the ramp, with a value range of 0-2. The larger the value, the greater the pressure. Traffic capacity refers to the maximum number of traffic entities (vehicles or pedestrians) that may pass through a certain lane or section at a certain point on the road per unit time, also known as road traffic capacity, generally expressed in vehicles / h. Vehicles mostly refer to cars. When other vehicles are mixed in, the equivalent standard vehicle (car) of equivalent traffic capacity is used as the unit (pcu). The total length of the ramp represents the actual driving distance from the entrance to the exit of the ramp, in meters. The congestion index is used to indicate the current traffic operation status and the degree of deviation from the design capacity.

[0047] After the congestion index is calculated, it is necessary to evaluate the bearing pressure of the ramp in combination with its physical characteristics. Specifically, first obtain the design capacity and actual total length data of the ramp, and use the ratio of the congestion index to the capacity as the basic pressure value; then determine the correction coefficient based on the difference between the total length of the ramp and the standard length; finally, multiply the basic pressure value by the correction coefficient to obtain the final pressure index. The calculation process needs to consider the geometric conditions of the ramp, traffic composition and other influencing factors.

[0048] In some embodiments, the pressure index can be calculated in a variety of ways: optionally, based on a linear weighted model, the congestion index is first standardized to obtain a basic score, then the capacity utilization rate is calculated to obtain a capacity score, and then the geometric score is calculated according to the ramp length, and finally the three scores are weighted according to the weight of 0.4:0.4:0.2 to obtain the pressure index; optionally, based on the fuzzy comprehensive evaluation method, a fuzzy evaluation index system of the pressure index is established, including three primary indicators of congestion degree, capacity utilization rate and geometric conditions, and the indicator weights are determined through hierarchical analysis, and finally the pressure index is obtained by fuzzy operation. It can be understood that other mathematical models can also be used to calculate the pressure index, which is not limited here.

[0049] S204: Divide each of the entrance and exit ramps into a regular ramp and a controlled ramp according to the pressure index.

[0050] Among them, conventional ramps refer to ramps with low pressure index and conventional traffic organization. Control ramps refer to ramps with high pressure index and special control measures. Ramp classification refers to the process of dividing ramps into different management levels according to pressure index. Pressure index threshold is used to represent the judgment standard of ramp classification, and the general value is 1.2.

[0051] After obtaining the pressure index of all ramps, the ramps need to be classified and managed. Specifically, first determine the classification threshold of the pressure index, usually 1.2 is used as the critical value for dividing regular ramps and controlled ramps; then, the ramps with a pressure index less than the threshold are classified as regular ramps, and the ramps with a pressure index greater than or equal to the threshold are classified as controlled ramps; finally, establish a classification result database to record the category attributes and main characteristic parameters of each ramp. The classification results will serve as an important basis for the preparation of subsequent ramp design plans.

[0052] In some embodiments, ramp classification can be achieved in a variety of ways: Optionally, based on a fixed threshold method, a pressure index of 1.2 is set as a classification threshold, a single value comparison is performed on the ramp pressure index, and ramps greater than or equal to 1.2 are classified as control ramps, and ramps less than 1.2 are classified as regular ramps, and the classification results are updated regularly; Optionally, based on a cluster analysis method, the pressure index of all ramps is used as sample data, and the K-means clustering algorithm is used to automatically divide the ramps into two categories, and the category with a larger cluster center value is determined as a control ramp, and the category with a smaller cluster center value is determined as a regular ramp. It is understandable that other classification methods can also be used to achieve ramp type classification, which is not limited here.

[0053] S205: Prepare a ramp design plan for each of the conventional ramps and the control ramp, wherein the ramp design plan includes a conventional lane line layout and a gradient virtual and real line layout.

[0054] Among them, the ramp design plan refers to the detailed traffic organization technical plan formulated for a single ramp. Conventional lane line layout refers to the marking design method that uses a combination of solid and dotted lines with uniform starting and ending points to separate lanes. Gradual dotted and solid line layout refers to the marking design method that guides vehicles to change lanes in an orderly manner by staggering the transition positions of the solid and dotted lines between adjacent lane groups. The marking setting is used to regulate the vehicle's driving trajectory and prevent traffic conflicts. The design plan needs to consider the physical characteristics, traffic flow characteristics and safety requirements of the ramp.

[0055] After completing the ramp classification, it is necessary to formulate corresponding traffic organization plans for different types of ramps. Specifically, first collect basic data such as the geometric parameters and traffic characteristics of the ramp; then select the corresponding marking layout form according to the ramp type. Conventional ramps use a combination of solid and dashed lines with unified starting and ending points, and control ramps use gradient dashed and solid lines with staggered layouts; then determine the specific parameters of the markings, including the length of the solid line, the interval between dashed lines, the horizontal spacing, etc.; finally, compile a complete design plan including the plan layout, detailed marking drawings, construction instructions, etc.

[0056] In some embodiments, the preparation of ramp design schemes can be achieved in a variety of ways: optionally, a standardized design method is used, first the number and width of lanes are determined according to the ramp width, then the type and size of the markings are determined according to the design specifications, and then the marking layout diagram is drawn through CAD software, and finally a design description file is prepared; optionally, a customized design method is used, first the traffic flow characteristics are analyzed to determine the key design points, and then the traffic simulation software is used to evaluate different schemes, and then the design parameters are optimized according to the evaluation results, and finally a complete design file package is formed. It is understandable that other design methods can also be used to prepare ramp design schemes, which are not limited here.

[0057] S206, integrating each ramp design plan into a regional overall design plan.

[0058] The regional master design plan refers to a complete planning document formed by systematically integrating the design plans of all ramps in the region. Plan integration refers to the process of organically combining and coordinating independent ramp design plans. The design document includes general description, plan, section, marking details, etc. The integration process needs to consider the connection between ramps and the integrity of regional traffic organization.

[0059] After the design of each ramp is completed, it is necessary to integrate the system to form a regional overall plan. Specifically, first establish a unified plan template, including project overview, design basis, overall layout and other chapters; then organize the design plans of each ramp in a unified format, and mark the location information and key parameters; then specially design the connection area of ​​adjacent ramps to ensure the continuity of traffic organization; finally form a complete design document containing text description, drawings, engineering quantities and other contents.

[0060] In some embodiments, the integration of design solutions can be achieved in a variety of ways: optionally, a hierarchical integration method is adopted, where the design content is first divided into lane layout, marking system, sign system and other levels according to function, and then the layers are superimposed and reviewed respectively, and the relationship between each level is coordinated, and finally a unified design file is generated; optionally, a modular integration method is adopted, where the ramp design solution is first divided into several modules according to the region, and then the design elements in each module are unified, and then the transition connection between the modules is designed, and finally the overall solution is summarized. It is understandable that other integration methods can also be used to achieve the preparation of the overall regional design solution, which is not limited here.

[0061] The following is a more detailed description of the process of the method provided by this implementation. Figure 2 , which is another flow chart of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application.

[0062] S301, collecting traffic flow data and travel time data of all entrance and exit ramps in the target traffic area.

[0063] The target traffic area refers to a specific area that needs to be optimized for traffic organization, usually including one or more trunk roads and their associated entrance and exit ramp systems. The entrance and exit ramps are lanes connecting the trunk road to the ground road, including the entrance ramp (entering the trunk road from the ground road) and the exit ramp (driving out of the trunk road to the ground road). The traffic flow data refers to the number of vehicles passing through a specific section, in "vehicles / hour". The travel time data refers to the time required for a vehicle to pass the entire ramp, in "seconds".

[0064] Data collection is achieved in the following ways: vehicle detectors (such as coil detectors, video detectors, etc.) are installed at the entrance and exit of the ramp to record the number of vehicles passing through in real time and upload them to the traffic management system. At the same time, RFID readers or Bluetooth detectors are deployed in the ramp area to calculate the travel time of a single vehicle by identifying the vehicle feature code. The system counts the traffic flow data every 5 minutes and updates the average travel time every 1 minute. The collected data is transmitted to the data processing center via a wired or wireless network for storage and analysis. To ensure data reliability, the detection equipment needs to be calibrated and maintained regularly, and abnormal data needs to be cleaned before use.

[0065] S302: Calculate the congestion index of each entrance and exit ramp according to the vehicle flow data and the travel time data.

[0066] Traffic flow data reflects the intensity of ramp usage, and travel time data reflects travel efficiency. The two together determine the congestion level of the ramp. The congestion index is a dimensionless indicator for measuring traffic congestion, ranging from 0 to 1. The larger the value, the more serious the congestion.

[0067] The congestion index is calculated using the following method: First, convert the traffic volume data into the standard vehicle equivalent number of a 5-minute cycle, and convert the travel time data into relative delay time (the ratio of actual travel time to free flow time). Then according to the formula: Congestion index = α × (traffic volume / road capacity) + β × (relative delay time), where α and β are weight coefficients, and α + β = 1. According to actual conditions, α = 0.6 and β = 0.4 can be taken. The calculation results need to be smoothed to eliminate the impact of short-term fluctuations. When the congestion index is greater than 0.8, it indicates that the ramp is in a serious congestion state and traffic organization optimization measures need to be taken.

[0068] S303: Calculate the ratio of the actual traffic volume of each entrance and exit ramp to the designed traffic capacity according to the traffic volume data to obtain the traffic capacity utilization rate.

[0069] Actual traffic volume refers to the actual number of vehicles passing through a ramp per unit time, expressed in standard vehicle equivalents. The design capacity is the maximum capacity of a ramp under ideal conditions, determined by factors such as road geometry and design speed. The capacity utilization rate reflects the efficiency of ramp use and is an important indicator for evaluating traffic operation status.

[0070] Based on the traffic flow data, the ratio of the actual traffic volume of each entrance and exit ramp (expressed in standard vehicle equivalent number (pcu), that is, the actual number of vehicles passing through the ramp per unit time after conversion) to the design capacity (determined by factors such as road geometry and design speed, and determined as 1200pcu / hour for a single-lane ramp based on the "CJ37-2012 Urban Road Engineering Design Code") is calculated to obtain the capacity utilization rate.

[0071] The calculation process of capacity utilization is as follows: first, convert different types of vehicles into standard vehicle equivalents (the coefficient for small vehicles is 1.0, the coefficient for medium-sized vehicles is 1.5, and the coefficient for large vehicles is 2.0). Then, count the peak hour traffic flow, and calculate the annual average of the 15-minute traffic flow. The design capacity is determined according to the "Urban Road Engineering Design Code". When the design speed is 100km / h, the basic capacity is 2200pcu / h and the design capacity is 2000pcu / h; when the design speed is 80km / h, the basic capacity is 2100pcu / h and the design capacity is 1750pcu / h; when the design speed is 60km / h, the basic capacity is 1800pcu / h and the design capacity is 1400pcu / h. Capacity utilization = actual traffic volume (pcu) / design capacity (pcu / h). The design capacity is determined based on the design speed of the expressway junction and merge area where the ramp is located, and the corresponding design capacity value is determined from the "Urban Road Engineering Design Code". When the utilization rate exceeds 0.85, it indicates that the ramp is close to saturation; when the utilization rate exceeds 1.0, it indicates that the ramp is oversaturated and traffic demand management measures need to be taken.

[0072] S304: Calculate the ratio of the actual travel time to the ideal travel time of each entrance and exit ramp according to the travel time data to obtain a time delay rate.

[0073] Actual travel time refers to the actual time required for a vehicle to pass the entire ramp, including delays caused by traffic congestion, signal control and other factors, measured in seconds. Ideal travel time refers to the time required for a vehicle to pass the ramp at the design speed in a free flow state (without interference from other vehicles), measured in seconds. Time delay rate is a dimensionless indicator for measuring ramp operation efficiency, reflecting the degree of delay of actual travel time relative to the ideal state.

[0074] The specific steps for calculating the time delay rate include: first, collect the single-vehicle travel time data through license plate recognition or electronic tags, and calculate the average travel time every 5 minutes as the actual travel time. The ideal travel time is calculated based on the ramp length and design speed. For example, when the ramp length is 200 meters and the design speed is 40 kilometers per hour, the ideal travel time is 18 seconds. The time delay rate is equal to (actual travel time - ideal travel time) / ideal travel time. When the delay rate exceeds 1.0, it means that the travel time is more than twice the ideal state, and improvement measures need to be taken.

[0075] S305: The product of the traffic capacity utilization rate and the time delay rate is used as the congestion index.

[0076] The capacity utilization rate reflects the intensity of ramp usage, and its value range is 0 to 2.0. The time delay rate reflects the degree of reduction in traffic efficiency, and its value range is 0 to infinity. The congestion index comprehensively reflects the congestion status of the ramp through the product of these two indicators, which has a clear physical meaning.

[0077] The congestion index is calculated by the following method: normalize the capacity utilization rate and the time delay rate respectively so that their value ranges are limited to between 0 and 1. After normalization, multiply the two to get the congestion index. The specific formula is: Congestion Index = min (capacity utilization rate, 1) × min (time delay rate / 2, 1). The congestion index ranges from 0 to 1. When the index is greater than 0.6, it indicates mild congestion, when it is greater than 0.8, it indicates severe congestion, and when it is equal to 1, it indicates complete congestion.

[0078] S306. Calculate a pressure index according to the relationship between the congestion index, the total length of the ramp and the designed traffic capacity.

[0079] The total length of the ramp refers to the actual driving distance from the ramp entrance to the exit, measured in meters. The design capacity is the maximum traffic flow capacity of the ramp, measured in vehicles per hour. The pressure index is a comprehensive evaluation indicator that reflects the traffic pressure that the ramp bears under the existing geometric conditions.

[0080] The calculation method of pressure index is as follows: pressure index = congestion index × (1 + K1 × L / L0) × (1 + K2 × V / V0), where L is the actual length of the ramp, L0 is the standard ramp length (300 meters), V is the actual capacity, V0 is the standard capacity (1200 vehicles / hour), K1 and K2 are correction coefficients (0.2 and 0.3 respectively). When the pressure index is greater than 1.2, the ramp is under great traffic pressure; when it is greater than 1.5, the ramp operation state is close to the limit. The larger the pressure index, the more control measures are needed for the ramp.

[0081] S307: Divide each of the entrance and exit ramps into a regular ramp and a controlled ramp according to the pressure index.

[0082] The pressure index is a comprehensive indicator that reflects the pressure of ramp traffic operation, with a value range of 0 to 2. Conventional ramps refer to ramps with relatively small traffic pressure and standardized traffic organization methods. Controlled ramps refer to ramps with large traffic pressure and require special traffic organization measures. The classification standard of ramps is based on the threshold of the pressure index.

[0083] The specific implementation method of ramp classification is: set the pressure index threshold to 1.2. When the ramp pressure index is less than 1.2, it is classified as a conventional ramp; when the pressure index is greater than or equal to 1.2, it is classified as a controlled ramp. The classification results serve as the basis for the subsequent ramp design plan. For ramps near the threshold, a comprehensive evaluation is required in combination with the traffic operation status during peak hours. If the ramp pressure index fluctuates between 0.8-1.2, the final classification is determined based on its connection relationship with surrounding roads. The ramp classification results need to be updated regularly to adapt to changes in traffic demand.

[0084] S308. Set a conventional lane line on the main lane of the conventional ramp, wherein the conventional lane line includes a combination of solid and dotted lines with uniform starting and ending points.

[0085] The main lane is the main driving channel of the ramp, which is used for vehicles to pass through straight. Conventional lane lines are standard lane dividing lines, including two basic types: solid lines and dashed lines. Unified start and end points mean that the transition positions of solid lines and dashed lines remain consistent in the horizontal direction, which is easy for drivers to identify. The solid and dashed line combination is a marking form formed by combining solid line segments and dashed line segments according to specific rules.

[0086] The specific setting method of conventional lane lines is as follows: a lane dividing line is set between each adjacent lane on the main line of the ramp, with a solid line segment length of 20 meters, a dashed line segment length of 20 meters, and a dashed line interval of 6 meters. The solid line segment is set in the lane change prohibited area, and the dashed line segment is set in the lane change allowed area. The conversion point between the solid line and the dashed line is horizontally aligned between the lanes, and the conversion position should avoid the ramp curve section. The lane line width is 15 cm and the color is white. The reflective performance of the marking should meet the relevant requirements of "Road Traffic Signs and Markings" (GB5768).

[0087] S309. Stepped dashed lines are arranged on the control ramp, wherein the stepped dashed lines include a first dashed line combination between the first lane and the second lane, and a second dashed line combination between the third lane and the fourth lane, wherein the first dashed line combination and the second dashed line combination maintain a preset front-to-rear distance, and the ramp design includes a conventional lane line layout and a gradient dashed line layout.

[0088] The stepped dashed and solid lines are a special form of lane demarcation lines that guide vehicles to change lanes in an orderly manner by staggering the transition positions of the dashed and solid lines between adjacent lane groups. The first dashed and solid line combination and the second dashed and solid line combination are the marking units between the two lane groups. The preset front-to-rear distance refers to the longitudinal spacing between the two dashed and solid line combinations, which is used to ensure a safe distance for vehicles to change lanes.

[0089] The specific setting method of the stepped dashed and solid lines is as follows: the four lanes are divided into two groups, the first group includes the first lane and the second lane, and the second group includes the third lane and the fourth lane. The first dashed and solid line combination is set between the first group of lanes, including a 30-meter solid line and a 30-meter dashed line; the second dashed and solid line combination is set between the second group of lanes, and its starting point is 50 meters later than the first group. The width of the dashed and solid line combination is 20 cm, the solid line segment uses a solid white line, and the dashed line segment uses a dashed white line with a 3-meter line and a 6-meter interval. The preset front and rear distance between the two groups of dashed and solid line combinations is determined according to the ramp design speed, and is calculated based on the safe lane change operation time of not less than 3 seconds. For example, when the design speed is 60 kilometers per hour, the preset front and rear distance is not less than 50 meters.

[0090] The method for determining the preset front-back distance specifically includes: Obtain the design speed and lane width of the target road section; Calculate the safe driving time required for the vehicle to complete a single lane change based on the design speed; Calculate the minimum safe distance between the first dashed-solid line combination and the second dashed-solid line combination according to the design vehicle speed and the safe driving time; Calculate the lane change trajectory length according to the lane width; The minimum safety distance is compared with the lane change trajectory length, and the maximum value of the minimum safety distance and the lane change trajectory length is used as the preset front-to-back distance between the first dashed-solid line combination and the second dashed-solid line combination.

[0091] The design speed refers to the design standard speed of the ramp, usually 40-80 km / h, which is used to determine the road geometry design parameters. The lane width refers to the standard width of a single lane, generally 3.5-3.75 meters. The safe driving time refers to the shortest time required for a vehicle to complete a lane change, usually 3 to 5 seconds. The minimum safe distance is the longitudinal spacing calculated based on the design speed and safe driving time. The lane change trajectory length refers to the longitudinal distance required for a vehicle to complete a lane change, which is related to the lane width and lane change angle.

[0092] The specific process of determining the preset front-to-back distance is as follows: Get the design speed V (unit: km / h) and lane width W (unit: m) from the road section design file. For example, V=60 km / h, W=3.5 m. Determine the safe driving time T based on the actual vehicle test data. For a design speed of 60 km / h, take T=4 seconds. Calculate the minimum safe distance D1=V×T×(1 / 3.6), where 1 / 3.6 is the speed unit conversion coefficient. For V=60 km / h, D1=60×4×(1 / 3.6)=66.7 m. Calculate the lane change trajectory length D2=W×5, where 5 is the empirical coefficient. For W=3.5 m, D2=3.5×5=17.5 m. Compare the values ​​of D1 and D2, and take the larger value as the preset front-to-back distance D. In this example, D=max(66.7, 17.5)=66.7 m, which is rounded to 70 m in actual application.

[0093] S310, integrating each ramp design plan into a regional overall design plan.

[0094] The ramp design plan is a traffic organization plan formulated for a single ramp, including lane layout, marking settings, traffic signs, etc. The regional overall design plan is a complete planning document formed by systematically integrating the design plans of all ramps in the region. The integration process needs to consider the connection relationship between ramps, traffic flow conversion and overall regional coordination.

[0095] The integration method of the regional master design plan includes the following steps: First, establish a standardized plan template, including general description, floor plan, line detail, sign layout and other chapters. Enter the design plan of each ramp into the template in a unified format, and mark the basic information such as ramp number, location coordinates, connecting section, etc. Specially design the connection area of ​​adjacent ramps to ensure the continuity of lane conversion and line transition. Prepare a regional traffic sign system to achieve unified guidance of sign information. Prepare a traffic organization plan, marking the location and main design elements of all ramps. Finally, form a complete file package including design description, drawings, and bill of quantities.

[0096] like Figure 4 As shown, it is a scene design diagram of the entrance and exit ramp traffic organization method based on traffic flow characteristics in the embodiment of the present application exist Figure 4In the figure, part a details different types of road markings and their meanings. The solid yellow line serves as a warning to drivers and is a sign that prohibits vehicles from crossing. There are different rules for the white dashed and solid lines. Vehicles are allowed to cross temporarily on the dashed side, but are prohibited from crossing temporarily on the solid side, so as to regulate the driving routes of vehicles. In part b, the gradient section is marked with distances "D" and "E", emphasizing that the vehicle needs to drive smoothly for 3 seconds after changing lanes, and travel a distance of about 66m at a speed of 80km / h to prevent vehicles from changing lanes continuously and ensure road driving order and safety. Part c focuses on the calculation process of the minimum length of the lane change section. The calculation formula is L=0.625VW, where V is the speed and W is the lane width. At a speed of 80km / h, the minimum distance for changing a lane is calculated to be 186m. This distance is determined by taking into account that on a road with a design speed of not less than 60km / h, the crossing of the same-direction lane dividing line segment and the interval are 600cm and 900cm respectively, ensuring that vehicles can change lanes within a safe distance.

[0097] It should be noted that Figure 4 The colors of the solid and dotted lines have been processed and can be any color in practice. The description in this application does not represent the actual color.

[0098] S311, sending the overall design plan of the area to the target client.

[0099] The target client refers to the terminal device used to receive and display the design plan, including the engineering management system, mobile applications, etc. The design plan is a digitally processed engineering file, which contains multiple formats such as text documents, CAD drawings, and 3D models. The sending process needs to ensure the integrity and security of data transmission.

[0100] First, classify and organize the design solution files according to a unified naming rule and compress and package them in ZIP format. Establish a file transfer server and configure FTP or HTTPS protocol for data transmission. Develop a file receiving module to support breakpoint resumption and file integrity verification. Install dedicated viewing software on the target client to support online browsing and annotation of various engineering files. Set up file access permission control to ensure that only authorized users can view and download solution files. Establish a file version management mechanism to record the history of each update and modification.

[0101] S312. Determine the location of the variable information sign in the overall design plan of the area.

[0102] Variable message signs are electronic display devices used to release real-time traffic information and management instructions to drivers. The installation location refers to the specific location where the variable message sign is installed, which needs to meet the requirements of visibility, safety and maintenance convenience. The overall regional design plan needs to coordinate the planning of the variable message sign system to form a complete information release network.

[0103] The method for determining the location of variable information signs is as follows: First, divide a control section every 500 meters along the ramp direction as a candidate installation location. In each control section, select a location that meets the following conditions: the sight distance is not less than 200 meters, the distance from other traffic signs is not less than 100 meters, and there are power supply conditions and communication signal coverage to facilitate equipment installation and maintenance. Then determine the installation section based on traffic flow characteristics, including: 100 meters before the ramp entrance, used to publish ramp traffic status; 150 meters before the starting point of the lane conversion area, used to announce lane change information; 200 meters before the ramp exit, used to indicate the exit direction. A detailed layout diagram must be drawn for each installation location, marking supporting facilities such as column foundations, power supply lines, and communication pipelines.

[0104] S313. Plan the installation section of the LED display screen according to the gradient virtual and real line layout. The section is located at a preset distance before the starting point of each group of virtual and real line combinations. The LED display screen is used to remind the driver when to change lanes.

[0105] The gradient dashed line layout refers to a dashed line combination system set at a specific spacing on the ramp. The LED display is an information display device made of a light-emitting diode array, and its size is generally 2 meters by 3 meters. The installation section refers to the specific installation position of the LED display, including the horizontal position and the vertical position. The preset distance refers to the vertical spacing between the LED display and the starting point of the dashed line combination, and the standard value is 100 meters.

[0106] The planning method for the installation section of the LED display is as follows: First, determine the starting coordinates of each set of virtual and real line combinations, and mark the position on the plan. Delineate the installation section 100 meters before the starting point, and the section position must avoid the ramp curve section and the slope change section. Measure the cross-sectional width at the installation section to determine the cantilever length of the LED display. The installation height of the display is 5.5 meters, and the column foundation is 2 meters away from the outer edge of the shoulder. Each LED display is equipped with an independent power supply system and communication unit, and the display content includes: lane status indication, lane change suggestion information, driving speed prompts, etc. The displayed information should be clear and stable, and the character height should not be less than 40 cm.

[0107] S314: Obtain traffic flow data and traffic status data of each conventional ramp.

[0108] Traffic flow data refers to the number of vehicles passing through the ramp section per unit time, including the total number of vehicles and the statistical values ​​of different vehicle types. Traffic status data includes parameters reflecting traffic operation characteristics such as vehicle speed, headway, and occupancy rate. Conventional ramps refer to ramp sections that adopt standard traffic organization methods.

[0109] Data acquisition is carried out in the following way: a set of vehicle detectors, including loop coils and video detectors, are set up at the entrance and exit of the ramp. The coil detector is buried 20 cm below the road surface and is used to collect vehicle flow, speed and occupancy data with a sampling period of 20 seconds. The video detector is installed on the monitoring pole, covering a 100-meter detection area, and is used to identify vehicle models and abnormal events. All detection data is transmitted to the traffic management center in real time through a dedicated communication network, and is stored in the database after data screening and cleaning. The data recording format includes fields such as timestamp, vehicle model, speed, lane number, etc. The system generates a statistical report every 5 minutes for traffic status evaluation.

[0110] S315: Calculate a peak-hour congestion index based on the traffic flow data and the traffic status data.

[0111] Peak hours refer to the time when traffic demand is concentrated, usually including 7:00-9:00 and 17:00-19:00 on weekdays. The congestion index is a comprehensive indicator to measure the traffic operation status, reflecting the degree of reduction in road traffic efficiency. Traffic flow data and traffic status data are the basic data for calculating the congestion index.

[0112] The calculation method of the peak-hour congestion index is as follows: First, determine the evaluation period and divide the peak hour into 15-minute evaluation intervals. For each evaluation interval, calculate: flow saturation = measured flow / design capacity; speed saturation = design speed / measured average speed; occupancy coefficient = measured occupancy / critical occupancy (take 20%). Then use the weighted average method to calculate the congestion index: congestion index = 0.4×flow saturation + 0.4×speed saturation + 0.2×occupancy coefficient. The calculation results are normalized so that the value range of the congestion index is 0-1. The system records the peak-hour congestion index of each working day, and calculates the weekly and monthly averages to evaluate the operation effect of the ramp.

[0113] S316: When the peak-hour congestion index of a conventional ramp exceeds a preset congestion threshold, a ramp reconstruction suggestion is generated.

[0114] Conventional ramps refer to ramps that adopt standard traffic organization methods and do not require special control measures. The peak congestion index is a quantitative indicator that reflects the traffic operation status of the ramp during peak hours, with a value range of 0-1. The preset congestion threshold is the critical value for judging whether the ramp needs to be renovated, and the standard value is 0.85. The ramp renovation proposal is an engineering and technical solution proposed based on the analysis of traffic operation status, including renovation content, technical parameters and implementation steps.

[0115] The process of generating ramp reconstruction suggestions specifically includes: the system monitors the peak-hour congestion index of conventional ramps every day and records the number of times it exceeds the 0.85 threshold. When the peak-hour congestion index of a conventional ramp exceeds the threshold for five consecutive working days, the reconstruction suggestion generation program is started. First, the geometric characteristics of the ramp are analyzed, including: ramp length, number of lanes, curve radius, longitudinal section, etc. Secondly, the traffic operation characteristics are diagnosed, including: traffic composition, lane change behavior, speed distribution, accident-prone points, etc. Then a reconstruction plan is formulated, including: increasing the number of lanes, adjusting lane width, optimizing marking layout, adding traffic signs, and erecting variable information signs. The scope of reconstruction, project quantity and quality requirements must be clearly stated in the plan. Finally, a ramp reconstruction suggestion report is formed, which includes: current situation analysis, reconstruction plan, effect prediction, investment estimation, implementation plan and other chapters. The report is submitted to the traffic management department as a basis for engineering decision-making.

[0116] like Figure 5 As shown, it is another scenario design diagram of the entrance and exit ramp traffic organization method based on traffic flow characteristics in an embodiment of the present application.

[0117] Part a shows the marking design of multiple road sections, including different functional areas such as gradient sections and deceleration sections. These markings guide vehicles to drive in an orderly manner through reasonable combinations, ensuring that vehicles can safely decelerate or change lanes when entering special sections.

[0118] Part b and part c mainly explain the meaning of road markings and vehicle driving regulations. The figure clearly states that vehicles are allowed to temporarily cross the dotted line (white) side, while vehicles are prohibited from crossing the solid line (yellow) side. This marking regulation can effectively restrict the driving route of vehicles and reduce traffic accidents caused by random lane changes.

[0119] In addition, part C indicates that the distance a vehicle travels in 3 seconds at a speed of 80 km / h is 66 meters, and the minimum distance required to safely change lanes is 186 meters. These data provide a scientific basis for road planning and vehicle driving, ensuring road traffic safety and smoothness.

[0120] It should be noted that Figure 5 The colors of the solid and dotted lines have been processed and can be any color in practice. The description in this application does not represent the actual color.

[0121] The following describes the entrance and exit ramp traffic organization system in the embodiment of the present invention from the perspective of hardware processing. Figure 6 , which is a schematic diagram of a physical device structure of an entrance and exit ramp traffic organization system in an embodiment of the present application.

[0122] It should be noted that Figure 6 The structure of the entrance and exit ramp traffic organization system shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0123] like Figure 6 As shown, the entrance and exit ramp traffic organization system includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 602 or the program loaded from the storage part 608 to the random access memory (RAM) 603, such as executing the method described in the above embodiment. In RAM 603, various programs and data required for system operation are also stored. CPU 601, ROM 602 and RAM 303 are connected to each other through bus 604. Input / output (I / O) interface 605 is also connected to bus 604.

[0124] The following components are connected to the I / O interface 605: an input section 606 including an audio input device, a button switch, etc.; an output section 607 including a liquid crystal display (LCD) and an audio output device, an indicator light, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. A removable medium 611, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 610 as needed so that a computer program read therefrom is installed into the storage section 608 as needed.

[0125] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through the communication part 609, and / or installed from a removable medium 611. When the computer program is executed by the central processing unit (CPU) 601, various functions defined in the present invention are performed.

[0126] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, apparatus, or device.

[0127] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings.

[0128] Specifically, the entrance and exit ramp traffic organization system of this embodiment includes a processor and a memory. The memory stores a computer program. When the computer program is executed by the processor, the entrance and exit ramp traffic organization method based on traffic flow characteristics provided in the above embodiment is implemented.

[0129] As another aspect, the present invention further provides a computer-readable storage medium, which may be included in the entrance and exit ramp traffic organization system described in the above embodiment; or may exist independently without being assembled into the entrance and exit ramp traffic organization system. The above storage medium carries one or more computer programs, and when the above one or more computer programs are executed by a processor of the entrance and exit ramp traffic organization system, the entrance and exit ramp traffic organization system implements the entrance and exit ramp traffic organization method based on traffic flow characteristics provided in the above embodiment.

[0130] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0131] As used in the above embodiments, the term "when..." may be interpreted to mean "if..." or "after..." or "in response to determining..." or "in response to detecting...", depending on the context. Similarly, the phrases "upon determining..." or "if (the stated condition or event) is detected" may be interpreted to mean "if determining..." or "in response to determining..." or "upon detecting (the stated condition or event)" or "in response to detecting (the stated condition or event)", depending on the context.

[0132] Those skilled in the art can understand that to implement all or part of the processes in the above-mentioned embodiments, the processes can be completed by computer programs to instruct related hardware, and the programs can be stored in computer-readable storage media. When the programs are executed, they can include the processes of the above-mentioned method embodiments. The aforementioned storage media include: ROM or random access memory RAM, magnetic disk or optical disk and other media that can store program codes.

Claims

1. A method for organizing entrance and exit ramp traffic based on traffic flow characteristics, characterized in that: Applied to the entrance and exit ramp traffic organization system, the method comprises: Collect traffic volume data and travel time data of all entrance and exit ramps in the target traffic area; Calculate the congestion index of each of the entrance and exit ramps according to the vehicle flow data and the travel time data; Calculating a pressure index of each of the entrance and exit ramps according to the congestion index, the capacity of the entrance and exit ramps, and the total length of the ramps; Dividing each of the entrance and exit ramps into a regular ramp and a controlled ramp according to the pressure index; Prepare a ramp design plan for each of the conventional ramps and the controlled ramps, wherein the ramp design plan includes a conventional lane line layout and a gradient dashed line layout; Each of the ramp design solutions is integrated into a regional overall design solution.

2. The method according to claim 1, characterized in that The step of calculating the pressure index of each of the entrance and exit ramps according to the congestion index, the traffic capacity of the entrance and exit ramps, and the total length of the ramps specifically includes: Calculating the ratio of the actual traffic volume of each entrance and exit ramp to the designed traffic capacity according to the traffic volume data to obtain the traffic capacity utilization rate; Calculating the ratio of the actual travel time to the ideal travel time of each entrance and exit ramp according to the travel time data to obtain a time delay rate; The product of the traffic capacity utilization rate and the time delay rate is used as the congestion index; The pressure index is calculated based on the relationship between the congestion index, the total length of the ramp and the designed traffic capacity.

3. The method according to claim 1, characterized in that: The step of preparing a ramp design plan for each of the conventional ramps and the control ramp specifically includes: Setting a conventional lane line on the main lane of the conventional ramp, wherein the conventional lane line includes a combination of a solid line and a dotted line with a uniform starting and ending point; A stepped dashed and solid line is set on the control ramp, and the stepped dashed and solid line includes a first dashed and solid line combination set between the first lane and the second lane, and a second dashed and solid line combination set between the third lane and the fourth lane, and the first dashed and solid line combination and the second dashed and solid line combination maintain a preset front and rear distance.

4. The method according to claim 3, characterized in that The method for determining the preset front-to-back distance specifically includes: Obtain the design speed and lane width of the target road section; Calculating the safe driving time required for the vehicle to complete a single lane change based on the design vehicle speed; Calculate the minimum safe distance between the first dashed-solid line combination and the second dashed-solid line combination according to the design vehicle speed and the safe driving time; Calculating a lane change trajectory length according to the lane width; The minimum safety distance is compared with the lane change trajectory length, and the maximum value of the minimum safety distance and the lane change trajectory length is used as a preset front-to-rear distance between the first dashed-solid line combination and the second dashed-solid line combination.

5. The method according to claim 1, characterized in that After the step of integrating each ramp design scheme into a regional overall design scheme, the method further comprises: Determining the location of the variable information sign in the overall design plan of the area; The installation section of the LED display screen is planned according to the gradient virtual and real line layout, and the section is located at a preset distance before the starting point of each group of virtual and real line combinations. The LED display screen is used to prompt the driver when to change lanes.

6. The method according to claim 1, characterized in that After the step of integrating each ramp design scheme into a regional overall design scheme, the method further comprises: Acquiring traffic flow data and traffic status data of each conventional ramp; Calculate a peak-period congestion index based on the traffic flow data and the traffic status data; When the peak-hour congestion index of a conventional ramp exceeds a preset congestion threshold, a ramp reconstruction suggestion is generated.

7. The method according to claim 1, characterized in that After the step of integrating each ramp design scheme into a regional overall design scheme, the method further comprises: The overall regional design plan is sent to the target client.

8. An entrance and exit ramp traffic organization system, characterized in that: The entrance and exit ramp traffic organization system includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the entrance and exit ramp traffic organization system to execute the method described in any one of claims 1-7.

9. A computer-readable storage medium comprising instructions, characterized in that: When the instruction is executed on the entrance and exit ramp traffic organization system, the entrance and exit ramp traffic organization system is caused to execute the method as described in any one of claims 1-7.

10. A computer program product, characterized in that When the computer program product runs on an entrance and exit ramp traffic organization system, the entrance and exit ramp traffic organization system is enabled to execute the method according to any one of claims 1-7.

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