CN108648444A - A kind of signalized intersections postitallation evaluation method based on grid model - Google Patents

Abstract

The signalized intersections postitallation evaluation method based on grid model that the present invention provides a kind of, this method include：The grid model for building intersection, carries out a point direction to the track data of the Floating Car by urban road intersection based on grid model and handles；The traffic circulation parameter of intersection is obtained, which includes the passage average speed of the traffic flow by intersection, the transit time by intersection, the free flow transit time of intersection and intersection；The passage delay time at stop by intersection is calculated according to the traffic circulation parameter of intersection, postitallation evaluation is carried out to intersection according to the current delay time at stop.The present invention is under conditions of having abandoned map limitation, the reason of whole signal intersections that selection area can be traversed carry out real-time dynamic evaluation to intersection, and diagnosis intersection is delayed, the accuracy for ensuring evaluation diagnosis, improves intersection traffic efficiency.

Description

A Grid Model-Based Operational Evaluation Method for Signalized Intersections

technical field

The invention relates to the technical field of traffic control, in particular to a method for evaluating the operation of a signalized intersection based on a grid model.

Background technique

At present, road traffic congestion has become a serious social phenomenon, and the impact of delays caused by signalized road intersections is particularly prominent. Using a reasonable timing scheme for signalized road intersections can effectively regulate the traffic efficiency of signalized road intersections. However, the current timing scheme for signalized road intersections often has some problems in practical applications, resulting in low efficiency. Therefore, it is necessary to evaluate and diagnose signalized road intersections in real time, and obtain a reasonable timing scheme based on the evaluation results.

At present, the method of using floating car data to evaluate the operation of signalized road intersections in the prior art mainly matches the floating car data to the road network through map matching technology, and then extracts the operating parameters of the signalized road intersection vehicles. for analysis.

The disadvantages of the above-mentioned method for evaluating the operation of signalized road intersections using floating car data in the prior art include: this method requires a large amount of calculation, which virtually increases the calculation burden of the computer.

Contents of the invention

The embodiment of the present invention provides a method for evaluating the operation of a signalized intersection based on a grid model to overcome the shortcomings of the prior art.

A method for evaluating the operation of a signalized intersection based on a grid model, including:

Constructing a grid model of road intersections, based on the grid model, the trajectory data of the floating car passing through the urban road intersections is processed in a direction-divided manner;

Acquire the traffic operation parameters of the road intersection according to the sub-direction processing results of the trajectory data of the floating car. Traffic time and the average speed of traffic at road intersections;

The traffic delay time for passing the road intersection is calculated according to the traffic operation parameters of the road intersection, and the operation evaluation of the road intersection is performed according to the traffic delay time.

Further, the grid model of constructing the road intersection includes:

Use the central coordinate data of the road intersection to determine the radiation area of the road intersection, and take the coordinate center point of the road intersection as the reference, select the range of 150m away from the center point of the road intersection in the upper direction, the lower direction, the left direction, and the right direction respectively. Radiation area, with the selected radiation area as the target, build a 3*3 grid model, each side of the grid model is 100m long, and the grids in the grid model are numbered from the lower left corner, from left to right , from the bottom to the top, numbered sequentially, grid Grid_ID numbered 0-8, respectively Grid_ID=0, Grid_ID=1, Grid_ID=2, Grid_ID=3, Grid_ID=4, Grid_ID=5, Grid_ID=6, Grid_ID= 7. Grid_ID=8, where Grid_ID=4 is the central grid.

Further, the directional processing of the trajectory data of the floating car passing through the urban road intersection based on the grid in the grid model includes:

Obtain the start grid in the grid model corresponding to the entry track point of the floating car through the road intersection, and the end grid in the grid model corresponding to the exit track point, according to the start grid, the The direction relationship of the destination grid in the 3*3 grid model is used to determine the running direction corresponding to the track data of the floating car.

Further, the determining the running direction corresponding to the trajectory data of the floating car according to the direction relationship between the starting point grid and the ending point grid in the 3*3 grid model includes:

In the 3*3 grid model, the top corresponds to the north, the bottom corresponds to the south, the left corresponds to the east, and the right corresponds to the west;

When the end point grid is directly above the starting point grid, the running direction corresponding to the trajectory data of the floating vehicle is northward straight;

When the end point grid is directly below the starting point grid, the running direction corresponding to the trajectory data of the floating vehicle is southward straight;

When the end grid is above the starting grid, the running direction corresponding to the trajectory data of the floating car is north to right;

When the end point grid is at the bottom right of the starting point grid, the running direction corresponding to the trajectory data of the floating car is south to right;

When the end point grid is at the upper left of the starting point grid, the running direction corresponding to the trajectory data of the floating car is north to left;

When the end point grid is at the lower left of the start point grid, the running direction corresponding to the trajectory data of the floating vehicle is south to left.

Further, according to the directional processing results of the trajectory data of the floating car, the traffic operation parameters of the road intersection are obtained, and the traffic operation parameters include the traffic flow through the road intersection and the transit time through the road intersection , the free flow time of the road intersection and the average speed of the road intersection, including:

According to the sub-direction processing results of the trajectory data of each floating car, the traffic volume Q _i in each direction inside the grid model of the road intersection and the total traffic volume (Q) of the road intersection are obtained, and the internal grid model is calculated at the same time The weight ω _i for each direction, and the weight δ _i for road intersections, where,

Among them, n represents the total number of road intersections:

Obtain the time T _i passing through the central grid of the grid model, and the total time Time passing through the road intersection, where:

Among them, t _tr[last] is the last time stamp of the track point passing through Grid_ID=4; t _tr[first] is the first time stamp of passing the track point of Grid_ID=4; The number of trajectories; ω _i is the weight coefficient of each direction of the road intersection:

Obtain the free flow time for road intersections in different directions, select the time period of the floating car trajectory data as 2:00-5:00, and the floating car trajectory with the instantaneous speed v>10m/s passing through the designated direction of the road intersection as the research object, Calculate the time of passing the road intersection, and after sorting the time of passing the road intersection, select the 15% quantile as the free flow time T _f ⁱ _ree of the specified direction:

Calculate the average traffic speed Avg_v for signal road intersections in different directions, select the center grid Grid_ID=4 as the research object, and calculate the average speed passing through the center grid, where,

Among them, v _j is the instantaneous velocity value passing through the Grid_ID=4 track point; count[tr] is the number of tracks passing in this direction within 5 minutes;

According to the time T _i passing through the central grid where the road intersection is located and the free flow time T _f ⁱ _ree , calculate the traffic delay D _i of the road intersection in each direction, and the total delay Delay of the road intersection, where,

Define Delay(0,10]→A; Delay(10,20]→B; Delay(20,30]→C;

Delay(30,40]→D; Delay(40,50]→E.

Further, the calculation of the delay time of passing the road intersection according to the traffic operation parameters of the road intersection, and the operation evaluation of the road intersection according to the delay time include:

Based on the grid model road intersection directional method, using the floating car trajectory data with a time interval of 3s, the average traffic speed Avg_v is calculated according to the directional delay time D _i of passing through the signal road intersection and the directional traffic of the signal road intersection and the traffic volume Q _i in each direction inside the intersection to construct a visualized polar coordinate diagram of the operation evaluation of the intersection, where the polar coordinate point represents the delay time Delay, the farther the distance is from the center point, the greater the delay; each polar coordinate point The size of represents the flow in this direction, the larger the point, the greater the flow; the value marked on each point represents the average speed through the road intersection, the faster the speed, the larger the value, combined with the delay time, flow and speed parameters on the Evaluate the operating status of road intersections.

From the technical solutions provided by the above embodiments of the present invention, it can be seen that the embodiments of the present invention propose a grid model-based operation evaluation method for signalized road intersections, which can traverse selected All the signalized road intersections in the area, conduct real-time dynamic evaluation of the road intersections every 5 minutes, diagnose the reasons for the delay at the road intersections, and then improve the traffic efficiency of the road intersections.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort.

Fig. 1 is a processing flow chart of a method for evaluating the operation of a signalized intersection based on a grid model and using floating car data provided by an embodiment of the present invention.

Fig. 2 is a logical flow chart of direction division based on a grid model provided by an embodiment of the present invention.

FIG. 3 is a schematic diagram of grid-based directional processing of trajectory data provided by an embodiment of the present invention.

Fig. 4 is a schematic diagram of a method for calculating traffic operation parameters of a road intersection based on a grid model according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of evaluating the internal direction of a road intersection provided by an embodiment of the present invention.

Detailed ways

In order to facilitate the understanding of the embodiments of the present invention, several specific embodiments will be taken as examples for further explanation below in conjunction with the accompanying drawings, and each embodiment does not constitute a limitation to the embodiments of the present invention.

The embodiment of the present invention adopts the grid model, abandons the limitation of the map, uses the floating car data with a time interval of 3s, and evaluates and diagnoses the intersection of signal roads in real time every 5 minutes, and makes a more refined evaluation of signal roads. Evaluate, diagnose and analyze intersections, which saves costs and improves calculation efficiency.

The processing flow of a method for evaluating the operation of a signalized intersection based on a grid model using floating car data provided by an embodiment of the present invention is shown in Figure 1, including the following processing steps:

Step 11. Construct a grid model of the urban road intersection, use the grid model to reconstruct the road intersection, and perform direction-divided processing on the track data of the floating car based on the grid in the grid model. Therefore, the limitation of the application map is abandoned, and the calculation efficiency is improved.

Step 12. Obtain traffic operation parameters in different directions according to the grid model, and obtain the traffic operation parameters of each road intersection in the city in real time. The traffic operation parameters include traffic flow through the road intersection, passing time through the road intersection, The free flow time of road intersections, the average speed of traffic at road intersections and the signal light parameters of road intersections.

Step 13: Calculate the delay time for passing through the intersection according to the traffic operation parameters of the intersection, evaluate the internal part direction of the intersection, and conduct a comprehensive evaluation for the entire intersection.

Step 14: Diagnose the road intersection, adjust the operation state of the road intersection under different traffic conditions, and improve the operation efficiency of the road intersection.

In a specific application of the present invention, the above step 11 specifically includes: FIG. 2 is a logic flow chart of the present invention based on the division of directions based on the grid model. As shown in Figure 2, the grid model adopted in the present invention reconstructs the road intersection, utilizes the central coordinate data of the road intersection to determine the radiation area of the road intersection, takes the coordinate center point of the road intersection as a benchmark, selects The range of 150m away from the center point of the road intersection in the up direction, down direction, left direction and right direction respectively is the radiation area. With the selected radiation area as the target, build a 3*3 grid model, each side of the grid model is 100m long, and the grids in the grid model are numbered from the lower left corner, from left to right, from the bottom To the top, numbered sequentially, the grid Grid_IDs numbered 0-8 are Grid_ID=0, Grid_ID=1, Grid_ID=2, Grid_ID=3, Grid_ID=4, Grid_ID=5, Grid_ID=6, Grid_ID=7, Grid_ID =8, where Grid_ID=4 is the central grid.

Fig. 3 is a schematic diagram of grid-based processing of floating car trajectory data according to an embodiment of the present invention. Based on the grid model, the trajectory data of the floating car passing through the road intersection is processed in a direction-divided manner, and the starting point grid in the grid model corresponding to the entering trajectory point of the floating vehicle passing through the road intersection is obtained, and the exiting trajectory point corresponds to The end grid in the grid model, according to the direction relationship between the start grid and the end grid in the 3*3 grid model, determine the corresponding operation of the track data of the floating car direction.

In the 3*3 grid model, the top corresponds to the north, the bottom corresponds to the south, the left corresponds to the east, and the right corresponds to the west;

When the end point grid is directly above the starting point grid, the running direction corresponding to the trajectory data of the floating vehicle is northward straight;

When the end point grid is directly below the starting point grid, the running direction corresponding to the trajectory data of the floating vehicle is southward straight;

When the end grid is above the starting grid, the running direction corresponding to the trajectory data of the floating car is north to right;

When the end point grid is at the bottom right of the starting point grid, the running direction corresponding to the trajectory data of the floating car is south to right;

When the end point grid is at the upper left of the starting point grid, the running direction corresponding to the trajectory data of the floating car is north to left;

When the end point grid is at the lower left of the start point grid, the running direction corresponding to the trajectory data of the floating vehicle is south to left.

Exemplarily, if the trajectory point enters in the direction of Grid_ID=1 and exits in the direction of Grid_ID=7, then the direction of the trajectory is straight north. If the trajectory point enters in the direction of Grid_ID=1 and exits in the direction of Grid_ID=3, then the direction of the trajectory is north to left. If the trajectory point enters in the direction of Grid_ID=1 and exits in the direction of Grid_ID=5, then the direction of the trajectory is turning right from north. Based on the same judgment method, the running trajectory direction of the floating car trajectory data is described.

In a specific application of the present invention, the specific steps of calculating the traffic operation parameters of the road intersection in the above-mentioned step 12 are as shown in Figure 4, and specifically include:

Using the method of dividing the direction of the road intersection in the grid model, the traffic volume (Q _i ) in each direction inside the road intersection and the total traffic volume (Q) are obtained, and the weight of each direction inside the road intersection is calculated at the same time ( ω _i ), and the weight of each road intersection in the city (δ _i ), where,

Among them, n represents the total number of road intersections.

The method of dividing the direction of the grid model road intersection is used to obtain the time (T _i ) of passing through the central grid where the road intersection is located inside the road intersection, and the total time of passing the road intersection (Time), where,

Among them, t _tr[last] is the last time stamp of the track point through Grid_ID=4; t _tr[first] is the first time stamp of the track point through Grid_ID=4; count[tr] sets the time for this direction (such as 5 The number of trajectories passing within minutes); ω _i is the weight coefficient of each direction of the road intersection.

Using the method of dividing the direction of the road intersection of the grid model, the free flow time is obtained for the direction of the road intersection, and the time period of the floating car data is selected as (2:00-5:00), and the instantaneous speed passing through the designated direction of the road intersection (v>10m/s) floating car trajectory is the research object, and the time to pass through the road intersection is calculated. After sorting the time of passing through the road intersection, select the 15% quantile as the free flow time of the specified direction

Using the method of dividing the direction of the grid model road intersection, the average speed (Avg_v) is calculated for the direction of the signal road intersection, and the center grid Grid_ID=4 is selected as the research object. Compute the average velocity across the grid, where,

Among them, v _j is the instantaneous velocity value passing through the Grid_ID=4 track point; count[tr] is the number of tracks passing in this direction within 5 minutes;

Using the method of dividing the direction of the road intersection in the grid model, the time (T _i ) of the obtained road intersection passing through the central grid where the road intersection is located, and the free flow time Calculate the traffic delay (D _i ) of the road intersection in each direction, and the total delay Delay, where,

Define Delay(0,10]→A; Delay(10,20]→B; Delay(20,30]→C;

Delay(30,40]→D; Delay(40,50]→E;

In a specific application of the present invention, the above-mentioned step 15 specifically includes: the formulation of the road intersection operation state evaluation method and the delay diagnosis optimization strategy are as follows:

Fig. 5 is a schematic diagram of evaluating the internal direction of a road intersection provided by an embodiment of the present invention. Based on the grid model road intersection method, using the floating car trajectory data with a time interval of 3s, and according to the traffic delay time (D _i ) obtained above through the signal road intersection, the signal road intersection is calculated according to the direction The average traffic speed (Avg_v), the traffic volume (Q _i ) in each direction inside the road intersection, based on this and output the evaluated visual road intersection operation evaluation polar coordinate map, as shown in Figure 5, where the polar coordinates The dot represents the delay time (Delay), the farther the distance is from the center point, the greater the delay. The size of each dot represents the flow in that direction, the larger the dot, the greater the flow. The value marked on each point represents the average speed through the road intersection. The faster the speed, the greater the value. After the data fusion algorithm, the operation status of the road intersection is evaluated by combining the delay time, flow and speed. Then, extract the timing data of signal lights at road intersections, and match the passing time and traffic flow in the traffic operation parameters in combination with the operation status of road intersections to obtain a reasonable timing scheme for signal lights at road intersections.

To sum up, the embodiment of the present invention proposes a grid model-based operation evaluation method for signalized road intersections, which can traverse all signalized road intersections in the selected area under the condition of abandoning the map restrictions, and each Carry out real-time dynamic evaluation of road intersections every 5 minutes, diagnose the reasons for road intersection delays, and then improve the traffic efficiency of road intersections.

The present invention abandons the complicated calculation in the map matching calculation, adopts the algorithm of the grid model in another way, improves the calculation efficiency, and adopts the track data of the floating car at an interval of 3s to ensure the accuracy and rationality of the evaluation and diagnosis. Improving traffic efficiency at road intersections and reducing delays at road intersections play a major role.

Those skilled in the art can understand that the accompanying drawing is only a schematic diagram of an embodiment, and the modules or processes in the accompanying drawing are not necessarily necessary for implementing the present invention.

Those skilled in the art can understand that: the modules in the device in the embodiment may be distributed in the device in the embodiment according to the description in the embodiment, and may also be changed and located in one or more devices different from the embodiment. The modules in the above embodiments can be combined into one module, and can also be further split into multiple sub-modules.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (6)

1. a kind of signalized intersections postitallation evaluation method based on grid model, which is characterized in that including：

The grid model for building intersection, based on the grid model to the Floating Car by the urban road intersection Track data carry out a point direction and handle；

The traffic circulation parameter of the intersection is obtained according to point direction handling result of the track data of the Floating Car, The traffic circulation parameter includes the traffic flow by intersection, the transit time by intersection, intersection The passage average speed of the free flow transit time and intersection of mouth；

The passage delay time at stop by intersection is calculated according to the traffic circulation parameter of the intersection, according to described The current delay time at stop carries out postitallation evaluation to the intersection.

2. according to the method described in claim 1, it is characterized in that, the grid model of the described structure intersection, including：

The radiation areas that intersection is determined using the centre coordinate data of intersection, in the coordinate of intersection On the basis of heart point, direction, lower direction, left direction, the right direction range apart from intersection central point 150m respectively in selection For radiation areas, using selected radiation areas as target, the grid model of 3*3 is built, each length of side 100m of grid model, Grid in grid model is numbered from the lower left corner, from left side to right side, from below to top, and number consecutively, number 0-8's Grid Grid_ID, be respectively Grid_ID=0, Grid_ID=1, Grid_ID=2, Grid_ID=3, Grid_ID=4, Grid_ID=5, Grid_ID=6, Grid_ID=7, Grid_ID=8, grid centered on wherein Grid_ID=4.

3. according to the method described in claim 1, it is characterized in that, the grid based in the grid model is to passing through The track data of the Floating Car of the urban road intersection carries out a point direction and handles, including：

It obtains Floating Car and dot grid is played by driving into the corresponding grid model of tracing point for intersection, be driven out to rail Terminal grid in the corresponding grid model of mark point, according to described dot grid, the terminal grid the 3*3 net Direction relations in lattice model determine the corresponding traffic direction of the track data of the Floating Car.

4. according to the method described in claim 3, it is characterized in that, playing dot grid, the terminal grid described in the basis Direction relations in the grid model of the 3*3 determine the corresponding traffic direction of the track data of the Floating Car, including：

Top in the grid model of the 3*3 corresponds to the north, and lower section corresponds to south, and left corresponds to east, and right corresponds to west；

When the terminal grid is in the surface of described dot grid, then the corresponding traffic direction of the track data of the Floating Car It keeps straight on for north orientation；

When the terminal grid is in the underface of described dot grid, then the corresponding traffic direction of the track data of the Floating Car It keeps straight on for south orientation；

When the terminal grid is in the upper right side of described dot grid, then the corresponding traffic direction of the track data of the Floating Car It turns right for north orientation；

When the terminal grid is in the lower right of described dot grid, then the corresponding traffic direction of the track data of the Floating Car It turns right for south orientation；

When the terminal grid is on the upper left side of described dot grid, then the corresponding traffic direction of the track data of the Floating Car Turn left for north orientation；

When the terminal grid is in the lower left of described dot grid, then the corresponding traffic direction of the track data of the Floating Car Turn left for south orientation.

5. according to the method described in claim 3 or 4, which is characterized in that the track data according to the Floating Car Point direction handling result obtain the traffic circulation parameter of the intersection, which includes by road friendship The traffic flow of prong passes through the transit time of intersection, the free flow transit time of intersection and intersection The passage average speed of mouth, including：

Divide direction handling result according to the track data of each Floating Car, obtains each side inside the grid model of intersection To passage volume of traffic Q_iAnd total volume of traffic (Q) of intersection, while calculating each direction inside grid model Weights omega_iAnd the weight δ of intersection_i, wherein

Wherein, n indicates intersection total quantity：

Obtain the time T of the central gridding by grid model_i, by intersection total time Time, wherein：

Wherein, t_tr[last]To pass through the last one timestamp of Grid_ID=4 tracing points；t_tr[first]To pass through Grid_ID=4 rails First timestamp of mark point；Count [tr] be direction setting time in by tracking quantity；ω_iIt is each for intersection The weight coefficient in direction：

Direction is divided to obtain the free flow time intersection, the period for choosing Floating Car track data is 2:00-5:00, lead to Cross the instantaneous velocity v of intersection assigned direction>The floating wheel paths of 10m/s are research object, and calculating passes through intersection The time of mouth chooses free flow of 15% quantile as the assigned direction after the time-sequencing by intersection The row time

Direction calculating is divided to be averaged passage rate Avg_v signal intersection, Selection Center grid Grid_ID=4 is as grinding Study carefully object, calculate the average speed by the central gridding, wherein

Wherein, v_jTo pass through the Instantaneous velocity values of Grid_ID=4 tracing points；Count [tr] be in the direction 5 minutes by rail Mark quantity；

According to the time T by the central gridding where intersection_iWith free flow transit timeCalculate intersection Divide the current delay D in direction_i, the total delay Delay of intersection, wherein

Definition Delay (0,10] → A；Delay(10,20]→B；Delay(20,30]→C；

Delay(30,40]→D；Delay(40,50]→E.

6. according to the method described in claim 5, it is characterized in that, described join according to the traffic circulation of the intersection Number calculates the delay time at stop by intersection, and postitallation evaluation is carried out to the intersection according to the delay time at stop, Including：

The method for dividing direction based on grid model intersection is the Floating Car track data of 3s using time interval, according to It is described to divide direction passage delay time at stop D by signal intersection_i, signal intersection divide direction calculating averagely current speed Spend the passage volume of traffic Q of all directions inside Avg_v and intersection_iBuild visual intersection postitallation evaluation pole seat It marks on a map, wherein polar coordinates point indicates delay time at stop Delay, and distance is remoter from central point, and delay is bigger；Each polar coordinates point is big The small flow for indicating the direction, point is bigger, and flow is bigger；The numerical value marked on each point indicates being averaged by intersection Speed, speed is faster, and numerical value is bigger, in conjunction with delay time at stop, flow and speed parameter to the operating status of intersection into Row evaluation.