Road actual traffic capacity calculation method under intelligent network connection vehicle formation

Abstract

The invention discloses a road actual traffic capacity calculation method under an intelligent network connection vehicle formation, and the method comprises the steps: carrying out the statistics of the formation number and average vehicle speed corresponding to the vehicle formation length at different times in a designated line according to historical monitoring data; according to the historical vehicle formation data set, estimating the vehicle distribution of the formation length at a given time and the headstock under the superspeed condition according to the average peak period and the peak period; and calculating the actual road traffic capacity of the vehicle formation under the ultra-high-speed condition based on the average vehicle head distance and the average vehicle speed.

Description

Technical Field

[0001] This invention relates to the field of intelligent transportation technology, specifically to a method for calculating the actual traffic capacity of highways under intelligent connected vehicle platooning. Background Technology

[0002] With the deep integration of next-generation information technologies such as big data, artificial intelligence, machine vision, blockchain, BeiDou, and 5G into the highway transportation sector, digitalization, networking, and intelligence are contributing to the high-quality development of highway transportation. Simultaneously, highway development will fully utilize technologies such as advanced driver assistance systems (ADAS), vehicle-to-everything (V2X), vehicle-road cooperation, and autonomous driving, leveraging reliable communication networks to significantly enhance the platooning capabilities of highway systems, further reduce vehicle headway, substantially increase highway capacity, and achieve a multiplier effect in improving the traffic efficiency of road segments / networks.

[0003] Therefore, it is urgent to estimate the actual traffic capacity of highways under intelligent connected vehicle platooning, so as to explore the new patterns and characteristics brought about by the new traffic flow of intelligent connected vehicle platooning. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for calculating the actual traffic capacity of highways under intelligent connected vehicle platooning.

[0005] This invention discloses a method for calculating the actual traffic capacity of highways under intelligent connected vehicle platooning, including: Step 1: Analyze the historical platooning of intelligent connected vehicles on the road segment: Based on historical monitoring data, statistically analyze the platooning of vehicles on the designated route at different times. The number of vehicles in the formation corresponding to the following formation length Average vehicle speed ; Obtain the set of vehicle platooning data for the road segment Among them, data set , Number the data; Step 2: Based on historical vehicle platooning data, estimate the given time according to peak and off-peak periods. Lower formation length Vehicle distribution ; For the predicted vehicle platoon length The corresponding number of formations, of which ; Step 3, at average vehicle speed Calculate vehicle speed under ultra-high speed conditions Corresponding average headway ; Step 4: Based on average headway and average vehicle speed , calculate the actual highway capacity of vehicle platoon in super-high speed case.

[0006] As a further improvement of the present application, in step 1, for any data set , the sum of the lengths of all platoons in the road section is equal to the total number of intelligent connected vehicles in the road section .

[0007] As a further improvement of the present application, the step 2 specifically includes: Step 21, calculate the time set corresponding to peak and flat peak: based on the historical vehicle platoon data set, use threshold to determine whether the given time is in peak or flat peak; if the total number of intelligent connected vehicles , then the time is in peak, otherwise it is in flat peak. According to the arrangement of time, determine the peak time set , and the others are in flat peak.

[0008] Step 22, according to the given time , determine whether it belongs to peak / flat peak, that is or , select the peak / flat peak historical data set corresponding to the time , and the data number set (including groups of data) in the vehicle platoon data set of the corresponding road section .

[0009] Step 23: according to the historical data set, use mean value to estimate the platoon length corresponding to the number of vehicles in the platoon distribution , which can be expressed as: (1) As a further improvement of the present application, the step 3 specifically includes: Step 31, calculate the headway of intelligent connected vehicles in platoon queue and the headway between non-platoon connected vehicles ; wherein the non-platoon vehicles include the head vehicle of the platoon queue and the front connected vehicle, the two intelligent connected vehicles on the road which are not in the platoon queue, etc.

[0010] Considering the length of the front vehicle , braking distance , reaction time , minimum safe parking distance , braking deceleration of front and rear vehicles and , and the speed of front and rear vehicles and The headway between non-platoon connected vehicles is shown as follows.Wherein, the reaction time is related to the speed interval, which can be obtained by table lookup according to the actual vehicle fitting condition.

[0011] (2) Here, in the case of a given rear vehicle speed, the front vehicle speed can be obtained by table lookup (the table can be obtained according to the average speed difference between the front and rear vehicles predicted by actual historical data).

[0012] In the platoon, considering that the front and rear vehicle speeds are consistent and the platoon reaction time is short, take as , then the headway of the intelligent connected vehicle can be expressed as (3) Step 32, calculate the average headway under the condition of super high speed, estimate the actual road traffic capacity; the length of the first group of vehicle platoon is . As a further improvement of the present application, in the step 32, the calculation formula of the average headway is:

[0013] (4) (4) Wherein, the total number of intelligent connected vehicles can be expressed as .

[0014] As a further improvement of the present application, in the step 4, the calculation formula of the actual road traffic capacity is: (5).

[0015] Compared with the prior art, the beneficial effects of the present application are: The present application analyzes the historical intelligent connected vehicle platoon data in the road section, estimates the platoon condition of intelligent connected vehicles with different platoon lengths based on a given time; at the same time, analyzes the headway of intelligent connected vehicles under the condition of super high speed and the headway between non-platoon connected vehicles, estimates the actual headway of vehicles; and further estimates the actual road traffic capacity under the condition of intelligent connected vehicle platoon. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a schematic diagram of the intelligent connected vehicle platoon running on the road.

[0017] Figure 2This is a flowchart of the method for calculating the actual traffic capacity of a highway under intelligent connected vehicle platooning disclosed in this invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The present invention will now be described in further detail with reference to the accompanying drawings: like Figure 2 As shown, this invention provides a method for calculating the actual traffic capacity of highways under intelligent connected vehicle platooning. When intelligent connected vehicles are operating on a highway, the method analyzes historical intelligent connected vehicle platooning data for a road segment to determine the probability distribution of platoons of different lengths. It also estimates the headway between intelligent connected vehicles in the platoon and the headway between non-platooned connected vehicles, thus estimating the actual traffic capacity under intelligent connected vehicle platooning conditions.

[0020] Specifically, it includes: Step 1: Analyze the historical platooning of intelligent connected vehicles on the road segment. The analysis reveals instances of platooned and non-platooned vehicles mixed together, as well as multiple platoons with varying lengths; see attached... Figure 1 As shown. Considering environmental factors such as communication latency and control stability, the maximum permissible formation length is... Based on historical monitoring data, statistics were compiled for this road section with data number... ,time The number of vehicles in a platoon corresponding to the platoon length Average vehicle speed As shown in Table 1. Where the platoon length is 1, it represents the number of intelligent connected vehicles not participating in the platoon.

[0021] Table 1 For any set of data The sum of all vehicles with platoon lengths in a road segment equals the total number of intelligent connected vehicles in that segment. ,Right now: (1) Therefore, in response to By analyzing historical monitoring data, a set of vehicle platooning data for a road segment can be obtained. Among them, data set Among them, average vehicle speed .

[0022] Step 2: Based on historical vehicle platooning data, estimate the given time according to peak and off-peak periods. Lower formation length Vehicle distribution ; For the predicted vehicle platoon length The corresponding number of formations, of which .

[0023] Specifically, it includes: Step 21: Calculate the time sets corresponding to peak and off-peak periods: Based on historical vehicle platooning data sets, use thresholds... To determine a given time Is it during peak or off-peak hours? (Given a specific time) Total number of intelligent connected vehicles Then time If it is a peak period, then it is a off-peak period; otherwise, it is an off-peak period. Determine the set of peak periods based on the time arrangement. The rest are off-peak periods.

[0024] Step 22: Based on the given time To determine whether it is a peak or off-peak period, i.e. or Historical data sets of peak / off-peak periods with a time deviation of half an hour were selected, along with corresponding vehicle platooning data sets for the road segments. Data ID set in (Include (Group data).

[0025] Step 23: Based on the historical dataset, determine the formation length. Corresponding platoon size and vehicle distribution This can be represented as the length of all formations in the historical dataset corresponding to peak / off-peak periods within a half-hour range of left and right deviation. The average number of corresponding formations, rounded down, is expressed as follows: (2) Step 3, under ultra-high speed conditions (i.e., average vehicle speed) ), calculate vehicle speed Corresponding average headway .

[0026] Specifically, it includes: Step 31: Calculate the headway between intelligent connected vehicles in the platoon. Headway between non-platoon connected vehicles Among them, non-platoon vehicles include the lead vehicle in a platoon and the connected vehicle in front, as well as two intelligent connected vehicles on the road that are not in a platoon.

[0027] Considering the length of the vehicle in front Braking distance reaction time Minimum safe parking distance Braking deceleration of front and rear vehicles and and the speed of the vehicles in front and behind. and Headway between non-platoon connected vehicles The following is an explanation. Among them, the reaction time... It is related to the speed range and can be obtained by looking up a table based on the actual vehicle fitting results.

[0028] (3) Here, given the speed of the following vehicle, the speed of the preceding vehicle can be obtained by looking up a table (the table can be obtained by predicting the average speed difference between the preceding and following vehicles based on actual historical data).

[0029] In a convoy, considering that the speeds of the vehicles in front and behind are the same and that the reaction time in a convoy is short, we take... for The front-to-back distance of intelligent connected vehicles It can be represented as (4) Step 32: Calculate ultra-high speed The average headway under certain conditions is used to estimate the actual traffic capacity of the highway; The length of the vehicle platoon is The average distance between vehicle heads The calculation formula is: (5) Among them, the total number of intelligent connected vehicles It can be represented as .

[0030] Step 4: Based on average headway Based on the average vehicle speed, calculate the actual highway capacity of vehicle platoons under ultra-high-speed conditions; the formula for calculating the actual highway capacity is: (6) Example: This invention provides a method for calculating the actual traffic capacity of highways under intelligent connected vehicle platooning, including: S1. Based on historical monitoring data, the vehicle platooning data for a certain road segment throughout the day is statistically analyzed. Some data from 9:00 to 10:30 is shown in Table 2: Table 2 S2, Select threshold The peak time set was calculated. The timeframe is [9:00, 10:00] and the off-peak time is (10:00, 10:30). Given a time of 9:30, obtain the historical dataset corresponding to the range [9:00, 10:00] with a deviation of half an hour to the left or right. The dataset is numbered as follows: The distribution of vehicle numbers in formations corresponding to formation lengths 1, 2, 3, and 4 is estimated using the mean and calculated as follows: (7) That is, the estimated formation lengths 1, 2, 3 and 4 corresponding to 9:30 correspond to 13, 12, 11 and 8 vehicles respectively, with a total of 103 intelligent connected vehicles.

[0031] S3. Given a speed of 180km / h, calculate the average headway.

[0032] Assuming the braking deceleration of the front and rear vehicles and Assuming a consistent reaction time of 0.6s, a vehicle length l of 5m, and a minimum safe distance d of 1m, the headway between intelligent connected vehicles in a platoon can be calculated as follows: m.

[0033] The maximum deceleration is taken as 4.5 m / s². 2 From the table, we can find that the reaction time between non-platooned connected vehicles at 180 km / h is 0.53 s. Taking the average speed difference between the vehicles in front and behind as 3.3 km / h, we can then determine the headway between non-platooned connected vehicles. The value is 42.6m.

[0034] The average frontage distance is calculated as follows: (8) S4. Based on the obtained average headway, the actual traffic capacity of the highway at a speed of 180 km / h can be calculated as follows: .

[0035] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for calculating the actual highway traffic capacity under the platoon of intelligent connected vehicles, characterized in that, Comprise: Step 1, according to historical monitoring data, count the number of vehicle platoons corresponding to the platoon length at different times in the specified line ;​​ Obtaining a set of road segment vehicle platoon data wherein the data of the set , is a data number; Step 2. Estimate the given time of day the length of the lower platoon the distribution of vehicles ; the predicted length of the vehicle platoon the corresponding number of platoons, where ; Step 3, average vehicle speed in the case of super high speed, the vehicle speed corresponding to the average vehicle headway ; Step 4, Calculation of the actual highway capacity of vehicle platoons in the case of superhighway speeds based on average headway and average vehicle speed . 2.The method of claim 1, wherein, In step 1, for any set of data , the sum of all platoon lengths of vehicles in the road segment equals the total number of intelligent connected vehicles in the road segment . 3.The method of claim 1, wherein, Said step 2, specifically comprising: Step 21, based on the historical vehicle platoon data set, using a threshold value to determine whether a given time is in a peak period or a flat period; when the total number of intelligent connected vehicles at a time is greater than the threshold value , then the time is a peak period, otherwise it is a flat period; according to the arrangement of time, determine the peak period time set , the others are flat periods; Step 22: Based on the given time To determine whether it is a peak or off-peak period, i.e. or Select time The corresponding peak / off-peak historical datasets and the corresponding road segment vehicle platooning data sets. Data ID set in ,gather Include Group data; Step 23, Estimate the platoon length using mean value from historical data set Corresponding platoon number of vehicles distribution is expressed as follows: (1)。 4. The method of claim 1, wherein the method is characterized by, Said step 3, specifically comprising: Step 31, calculating the headway of the intelligent connected vehicles in the platoon queue and the headway between the non-platoon connected vehicles ; wherein the non-platoon vehicles include the head vehicle of the vehicle platoon queue and the front connected vehicle, and the two intelligent connected vehicles on the road are not in the platoon queue Step 32, calculate super speed The average vehicle headway in the case of estimating the actual highway capacity; the first The length of the group vehicle platoon is .

5. The method of claim 4, wherein the method further comprises: In the step 32, the average vehicle headway The formula for calculating the average vehicle headway is: (2) Wherein, the total number of intelligent connected vehicles of the vehicle is represented as .

6. The method of claim 5, wherein the method further comprises: In the step 4, the calculation formula of the actual highway traffic capacity is: (3)。

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