Ramp interlacing area pavement marking adjusting method and device based on flow monitoring

Abstract

The invention belongs to the field of traffic management, and particularly relates to a ramp interlacing area pavement marking adjusting method based on flow monitoring, and a corresponding device and system thereof. The design thought of the method is to pre-determine the solid line length of a middle lane and an outer lane of a main road when the optimal traffic efficiency can be achieved in a traffic scene corresponding to typical main road traffic flow and ramp traffic flow. The method comprises the steps that firstly, road traffic flow is detected in real time, the current state is matched with a typical scene, then the adjusted marking length is determined according to a matching result, a standardized value of the marking length in a road is obtained through a preset conversion function, and finally the road marking is adjusted according to the standardized value. The invention further provides related equipment for implementing the strategy. Speed reduction caused by unreasonable lane changing of vehicles in a ramp area can be weakened, the congestion degree of a main road is reduced, and the traffic capacity of the main road is improved; therefore, the device has high practical value.

Description

Technical Field

[0001] The present invention belongs to the field of traffic management, and specifically relates to a ramp weaving area road marking adjustment method based on flow monitoring, a corresponding ramp weaving area road marking solid line length matching device and a ramp weaving area traffic management system. Background Art

[0002] With the development of economy and the increase of vehicle ownership rate, the traffic demand is also growing rapidly, which also leads to serious traffic congestion on urban roads. In order to improve traffic efficiency, many cities transform main roads into urban expressways. Although this improves the traffic speed of roads, it will also form some new traffic jams, such as the interweaving areas of the main road and ramps of expressways. When the traffic on the ramp reaches the bottleneck, it will greatly affect the normal traffic of vehicles on the main road, thus causing congestion on the main road and a sharp decrease in traffic capacity.

[0003] In order to improve the traffic efficiency of the main road and reduce the occurrence of traffic congestion, the traffic management department needs to implement certain control measures on the traffic flow in the ramp interweaving area. The commonly used measures are: 1. Change the control signal timing of the ramp to control the ramp rate of the arriving traffic flow, and change the green light duration to adjust the number of vehicles entering the main line. This solution can take into account the better traffic efficiency of the main line and the smaller loss time of ramp vehicles, making the main line traffic smoother while reducing the ramp queue phenomenon as much as possible. 2. By adjusting the ramp adjustment rate, changing the signal phase of the ramp signal control light, changing the traffic flow from the entrance ramp to the main line, and reducing the error between the expected occupancy rate and the actual occupancy rate of the main line of the expressway merging bottleneck area. This solution can effectively reduce the average travel time of ramp vehicles without reducing the traffic efficiency of the main line. 3. By obtaining the traffic flow information of the main road and ramp in the expressway interweaving area, adjusting the control strategy of the main road and ramp, and coordinating the main road control with the ramp control, the traffic capacity of the overall interweaving area is maximized. The above three existing control measures are to maximize the capacity of the ramp weaving area without changing the existing road facilities. Although these solutions can improve traffic efficiency to a certain extent, they do not consider the impact of individual vehicle movement behavior on the macro characteristics of traffic flow. Traffic flow theory research has found that unreasonable lane changes will cause traffic congestion on the main road and reduce its capacity. Therefore, there is still room for improvement in the existing various control strategies.

[0004] On this basis, based on the same concept as tidal roads, some technicians have proposed that the length of the solid line markings on the main road in the ramp weaving area can be dynamically adjusted, and then the lane change behavior position and timing of vehicles merging from the ramp to the main road can be adaptively regulated according to actual traffic conditions. This control strategy is indeed feasible in theory, but the existing technology still lacks an effective solution to implement this strategy. Summary of the invention

[0005] In order to achieve adaptive adjustment of the length of the no-crossing line (solid line) in the interweaving area of ​​the main road and the ramp in the expressway according to the road traffic flow, and solve the congestion problem in this area under overloaded traffic conditions, the present invention provides a method, device and system for adjusting the road markings in the ramp interweaving area based on flow monitoring.

[0006] The technical solution provided by the present invention is:

[0007] A method for adjusting road markings in ramp interweaving areas based on traffic flow monitoring is used to dynamically adjust the length of the solid line segment markings between the middle lane of the main road and the outer lane in the interweaving area of ​​the main road and the ramp according to the traffic flow of the main road and the ramp. The method includes the following steps:

[0008] S1: Divide the traffic flow into several intervals, and then establish multiple different traffic scenarios corresponding to the main road and the ramp in each traffic flow interval.

[0009] S2: The traffic simulation system is used to simulate the vehicle traffic efficiency in various traffic scenarios, and the corresponding solid line segment marking length that can achieve the maximum traffic efficiency is solved.

[0010] S3: Based on the analysis results of the previous step, establish a characterization of any main road traffic flow interval X p and ramp traffic flow interval Y p The corresponding decision function Z of the ideal solid line segment length p :

[0011] Z p =f(X p , Y p ).

[0012] S4: The traffic flow detection device installed upstream of the road in the direction of traffic flow detects the main road traffic flow X in the weaving area in real time within the specified detection period. t and ramp traffic volume Y t Then according to the decision function Z p Determine the ideal solid line segment length Z for the current period opt (X t , Y t ).

[0013] S5: query the length specifications of the blank part and the marked part of the dotted line segment in the current road marking according to the current road grade; and convert the calculated ideal solid line segment marking length Z into opt (X t , Y t ) is converted into an optimal solid line segment length Z that meets the length specification L .

[0014] S6: According to the converted optimal solid line segment marking length Z L , adjust the display status of the controllable marking assembly installed between the middle lane and the outer lane of the main road in the weaving area.

[0015] As a further improvement of the present invention, in step S1, assuming that the main road traffic flow is divided into m intervals and the ramp traffic flow is divided into n intervals, m×n different traffic scenarios can be established according to different combinations of the main road and ramp traffic flow intervals.

[0016] As a further improvement of the present invention, in step S2, the traffic simulation system includes TrafficGPT, SUMO, TESSNG, PTV VISSIM, Paramics, AIMSUN, Transmodeler, Trafficware, and Cube Dynasim.

[0017] As a further improvement of the present invention, in step S4, the vehicle flow detection device includes a camera and a data processing module at the back end thereof, and the method for realizing traffic flow monitoring is as follows:

[0018] The camera captures real-time images of the designated sampling area on the road. The data processing module obtains the video data collected by the camera and detects the vehicles appearing in it based on the target recognition algorithm and the target tracking algorithm; then the total number of vehicles passing through the sampling area within the designated detection period is counted, and the real-time traffic flow on the road is calculated based on the total number of vehicles and the duration of the detection period.

[0019] As a further improvement of the present invention, in step S4, the decision function Z opt (X t ,Y t ) is as follows:

[0020]

[0021] In the above formula, u and v represent the lengths of the one-dimensional vectors representing the main road traffic flow and ramp traffic flow, respectively.

[0022] As a further improvement of the present invention, in step S5, the expression of the conversion function is as follows:

[0023]

[0024] In the above formula, L s Indicates the length of the marked portion of the dashed line segment that can be crossed in the inner and outer lanes of the main road in the ramp weaving area that meets the current road grade specifications. L dIt indicates the length of the blank part in the dashed line segment of the inner and outer lanes of the main road in the ramp weaving area that meets the current road grade specifications.

[0025] As a further improvement of the present invention, in urban expressways, L s =600cm, L d =900cm.

[0026] As a further improvement of the present invention, in step S6, the controllable marking assembly uses an LED light strip embedded and installed at the lane dividing line. If the lamp beads at the specified position in the LED light strip emit white light, it means that this section has a mark, and if the lamp beads at the specified position are off, it means that this section has no road markings. The LED light strip simulates the solid line markings that are prohibited from crossing and the dotted line markings that are allowed to cross by controlling all the LED lamp beads in the specified interval to light up or light up intermittently.

[0027] The present invention also includes a device for matching the solid line length of road markings in a ramp interweaving area, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the aforementioned method for adjusting road markings in a ramp interweaving area based on flow monitoring is executed; thereby, the method for adjusting the solid line length of road markings in a ramp interweaving area based on the input main road traffic flow X is realized. t and ramp traffic volume Y t , output the optimal solid line segment marking length Z corresponding to the current traffic scene L .

[0028] The present invention also includes a ramp interweaving area traffic management system, which includes: two sets of vehicle flow detection equipment, a set of controllable marking components and a controller.

[0029] Among them, two sets of traffic flow detection equipment are installed on the main road and ramp upstream of the ramp interweaving area. The traffic flow detection equipment includes a camera and a data processing module at the back end. The camera is used to capture real-time images of the designated sampling area on the road; the data processing module obtains the video data collected by the camera and detects the vehicles appearing in it based on the target recognition algorithm and the target tracking algorithm; then the total number of vehicles passing through the sampling area within the specified detection period is counted, and then the traffic flow in the designated sampling area is calculated based on the total number of vehicles and the duration of the detection period.

[0030] The controllable marking assembly uses an embedded LED light strip installed at the lane dividing line. If the lamp beads at the specified position in the LED light strip emit white light, it means that this section has a mark, and if the lamp beads at the specified position are off, it means that this section has no road markings. The LED light strip simulates the solid line markings that are prohibited from crossing and the dotted line markings that are allowed to cross by controlling all or intermittent lighting of the LED lamp beads in the specified interval.

[0031] The controller includes a solid line length matching device for the road markings in the ramp weaving area as described above, and a light strip control unit. The solid line length matching device is used to output the optimal solid line segment marking length corresponding to the current traffic scene according to the main road traffic volume and ramp traffic volume detected by the traffic flow detection device. The light strip control unit is used to control the controllable marking component to display a solid line at a specified length upstream of the inner and outer lane dividing lines of the main road in the weaving area according to the optimal solid line segment marking length, and display a dotted line for the remaining part.

[0032] The technical solution provided by the present invention has the following beneficial effects:

[0033] The present invention provides a new traffic management solution that dynamically adjusts the solid line length of the boundary between the middle lane and the outer lane of the main road in the interweaving area of ​​the ramp of the urban expressway according to the real-time traffic flow on the main road and the ramp. In order to implement the new traffic management strategy provided by the present invention, the technicians used the traffic simulation system to solve the ideal marking length under different traffic conditions, and then designed a calculation method for calculating the marking length according to the real-time traffic flow based on the solution results, and finally designed a component based on LED that can realize dynamic adjustment of road markings.

[0034] The technical solution provided by the present invention can reduce the deceleration caused by unreasonable lane changes of vehicles in the ramp area, alleviate the congestion level on the main road, and improve the traffic capacity of the main road. The method has high practical value and can be put into practical application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a typical traffic map of the intersection of the ramp and the main road on an expressway.

[0036] Figure 2 This is a flowchart of the steps of the method for adjusting road markings in ramp weaving areas based on flow monitoring provided in Example 1 of the present invention.

[0037] Figure 3 A schematic diagram showing the marked and blank portions of the lane dividing line that can be crossed.

[0038] Figure 4 This is a system architecture diagram of the ramp weaving area traffic management system provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] Example 1

[0041] Figure 1 This is a typical traffic map of the intersection of the ramp and the main road in an expressway. As can be seen in the figure, the main road contains three lanes; namely lane 1, lane 2, and lane 3; among them, lane 2 is the middle lane of the main road, and lane 3 is the outer lane of the main road (close to the ramp side). The ramp includes two lanes, lane A and lane B. The area marked with slashes in the figure is the interweaving area of ​​the main road and the ramp. After the ramp extends to this area, lanes A and B gradually converge to the extended lane 4 along the outside of lane 3 in the main road.

[0042] In existing expressways, in order to prevent vehicles on the ramp from affecting the normal passage of high-speed traffic on the main road, vehicles in the extended lane 4 in the interweaving area are allowed to gradually cross the lane boundary line and enter the outer lane 3, but vehicles in the outer lane 3 are prohibited from crossing the lane boundary line to enter the middle lane 2. In fact, since there is a behavior of slow traffic on the ramp merging into the fast traffic on the main road, and before merging, the ramp vehicles will pass through a "bottleneck" section where the lane narrows and then expands again; therefore, when the ramp traffic volume is large, the interweaving area of ​​the ramp and the main road will inevitably be blocked, and even cause accidents in serious cases.

[0043] In fact, if the length of the solid line between the middle lane 2 and the outer lane 3 can be adaptively adjusted according to the traffic volume of the ramp and the main road, the traffic efficiency of vehicles in the weaving area can be significantly improved. For example, when the traffic volume on the main road is small and the traffic volume on the ramp is large, the length of the solid line between lane 2 and lane 3 is shortened so that the ramp vehicles can quickly merge into the main road; when the traffic volume on the main road is large or the traffic volume on the ramp is small, the length of the solid line between lane 2 and lane 3 is extended to prevent the ramp vehicles from affecting the normal traffic of the main road vehicles.

[0044] Based on the above road traffic management ideas, this embodiment provides a method for adjusting road markings in ramp weaving areas based on traffic flow monitoring, which is used to dynamically adjust the length of the solid line segment marking between the middle lane and the outer lane of the main road in the weaving area between the two, which is prohibited from crossing, according to the traffic flow of the main road and the ramp.

[0045] Specifically, Figure 2 As shown, the method comprises the following steps:

[0046] S1: Divide the traffic flow into several intervals, and then establish multiple different traffic scenarios corresponding to the main road and the ramp in each traffic flow interval.

[0047] In step S1, the main road traffic flow is divided into m intervals, and the ramp traffic flow is divided into n intervals. According to different combinations of the main road and ramp traffic flow intervals, m×n different traffic scenarios can be established.

[0048] For example, assuming that the maximum design traffic flow of the main road of a certain confluence is 25 vehicles / min, and the maximum design traffic flow of the ramp is 15 vehicles / min, and each interval length is 5 vehicles / min, the traffic flow state of the main road can be divided into 5 different intervals, and the traffic flow state of the ramp can be divided into 3 different intervals. In this state, the current confluence has 15 different traffic scenes, among which the easiest traffic condition is that the traffic flow of the upstream main road and the ramp are both in the range of 0-5 vehicles / min, and the busiest traffic condition is that the traffic flow of the upstream main road is in the range of 20-25 vehicles / min, and the traffic flow of the ramp is in the range of 10-15 vehicles / min.

[0049] S2: The traffic simulation system is used to simulate the vehicle traffic efficiency in various traffic scenarios, and the corresponding solid line segment marking length that can achieve the maximum traffic efficiency is solved.

[0050] The existing technology provides a variety of traffic simulation systems that can simulate the traffic conditions of roads under different traffic flow conditions, including TrafficGPT, SUMO, TESS NG, PTV VISSIM, Paramics, AIMSUN, Transmodeler, Trafficware, Cube Dynasim, etc. Using these systems, technicians can first design different roads and intersection scenarios. Then test the traffic efficiency at the intersection under each traffic scenario divided in the above steps. Then continuously modify the solid line length of the middle lane and the outer lane of the main road, and then solve the solid line segment marking length that can maximize the comprehensive traffic efficiency on the main road and the ramp; finally, record the solved result as the ideal solid line segment marking length under this traffic scenario.

[0051] S3: Based on the analysis results of the previous step, establish a characterization of any main road traffic flow interval X p and ramp traffic flow interval Y p The corresponding decision function Z of the ideal solid line segment length p :

[0052] Z p =f(X p , Y p ).

[0053] In the practical application of this embodiment, considering that the traffic flow interval is usually an integer, and the length of the solid line segment is also an integer or a decimal with only one significant digit, the decision function can be represented by constructing a state matrix Z. For example, the main road traffic flow and ramp traffic flow are represented by a one-dimensional vector X and Y, and then a two-dimensional matrix is ​​used to store the ideal solid line segment marking length under different main road traffic flow and ramp traffic flow conditions.

[0054] S4: The traffic flow detection device installed upstream of the road in the direction of traffic flow detects the main road traffic flow X in the weaving area in real time within the specified detection period. t and ramp traffic volume Y t .

[0055] Existing urban expressways usually have a large number of traffic flow detection devices installed. Typical traffic flow detection equipment includes a camera and its back-end data processing module. The camera is installed on a gantry or lamp pole above the road, and the data processing module completes the identification and calculation of traffic flow based on the images collected by the camera. Specifically, the method for the traffic flow detection device to realize traffic flow monitoring is as follows:

[0056] The camera captures real-time images of the designated sampling area on the road. The data processing module obtains the video data collected by the camera and detects the vehicles appearing in it based on the target recognition algorithm and the target tracking algorithm; then the total number of vehicles N passing through the sampling area within the designated detection period is counted, and then the real-time traffic flow Q on the road is calculated based on the total number of vehicles N and the duration of the detection period T: Q = N / T.

[0057] Then according to the decision function Z p Determine the ideal solid line segment length Z for the current period opt (X t , Y t ):

[0058]

[0059] In the above formula, u and v represent the lengths of the one-dimensional vectors representing the main road traffic flow and ramp traffic flow, respectively.

[0060] The calculation formula indicates that the current detected main road traffic flow X t and ramp traffic volume Y t The main road traffic flow interval X to which the typical values ​​of mainstream traffic flow and ramp traffic flow belong p and ramp traffic flow interval Y p , then the decision function Z p The length of the solid line segment marking in the traffic scene corresponding to the interval is taken as the ideal solid line segment marking length Z in the current state. opt (X t , Y t ).

[0061] S5: query the length specifications of the blank part and the marked part of the dotted line segment in the current road marking according to the current road grade; and convert the calculated ideal solid line segment marking length Z into opt (X t , Yt ) is converted into an optimal solid line segment length Z that meets the length specification L .

[0062] In practical applications, the lengths of markings on roads of different grades have corresponding specifications. Figure 3 As shown, in the crossable lane dividing line (dashed line), L s Indicates the length of the marked portion of the dashed line segment that can be crossed in the inner and outer lanes of the main road in the ramp weaving area that meets the current road grade specifications. L d Indicates the length of the blank part of the dashed line segment that can be crossed in the inner and outer lanes of the main road of the ramp weaving area that meets the current road grade specifications. For example, according to the national standard GB5768, for roads with a design speed of not less than 60km / h, the line segment and interval length that can be crossed over the dividing line of the same-direction lane are 600cm and 900cm respectively. Therefore, in urban expressways, L s The value is 600cm, L d The value is 900cm.

[0063] Based on the above reasons, the ideal solid line segment length calculated in the above step cannot be directly applied to all levels of roads. It should be converted into a value that meets the specifications according to the actual situation, and then the markings on the road should be adjusted accordingly. Specifically, in this embodiment, the expression of the conversion function used to achieve the solid line length conversion is as follows:

[0064]

[0065] The conversion idea of ​​this conversion function is to calculate the ideal solid line length Z opt (X t , Y t ) and then make a judgment:

[0066] (1) If Z opt (X t , Y t ) is exactly an integer multiple of the length of a dashed-solid line segment (a solid line segment plus a blank portion), then the optimal solid line length after conversion is Z opt (X t , Y t ).

[0067] (2) If Z opt (X t , Y t ) is divided by the length of a dashed-real line combination segment, the remainder is less than half of the length of a dashed-real line combination segment, that is: (L s +L d ) / 2, then the length of the solid road line is Z opt (Xt , Y t ) divided by the length of the combined dashed and solid line segment, rounded down, multiplied by the length of the combined dashed and solid line segment, and then added with the length of the solid line.

[0068] For example, the current Z opt (X t , Y t ) value is 36.5m, divided by the module length of the virtual and solid line module 15m and rounded down to 2, the remainder is 6.5m<7.5m, then the length of the solid line marking on the road surface is 2×15+6=36m.

[0069] (3) If Z opt (X t , Y t ) is divided by the length of a dashed-real line combination segment, and the remainder is greater than half of the length of a dashed-real line combination segment (L s +L d ) / 2, then the length of the solid road line is Z opt (X t , Y t ) divided by the length of the dashed and solid line module, rounded up, and then multiplied by the length of the dashed and solid line combined segment.

[0070] S6: According to the converted optimal solid line segment marking length Z L , adjust the display status of the controllable marking assembly installed between the middle lane and the outer lane of the main road in the weaving area.

[0071] In the scheme of this embodiment, in order to adjust the dividing line between the middle lane and the outer lane of the main road in the weaving area according to needs, a special controllable marking assembly is selected to be installed in this area to replace the traditional unchangeable paint-type road markings. Specifically, the controllable marking assembly in this embodiment adopts an embedded LED light strip installed at the lane dividing line. If the lamp beads at the specified position in the LED light strip emit white light, it means that this section has a mark, and if the lamp beads at the specified position are off, it means that this section has no road markings. The LED light strip simulates the solid line markings that are prohibited from crossing and the dotted lines that are allowed to cross in the road by controlling the LED lamp beads in the specified interval to light up or light up intermittently.

[0072] For example, in a section of a city expressway, when a solid line needs to be displayed, all the lamp beads in the LED light strip of that section are lit. When a dotted line needs to be displayed, the LED light strip in the section is divided into a combined section of every 15 meters, and the first 9m of the combined section (corresponding to L d ) is turned off, and the LED lamp beads in the last 6m (corresponding to L s ) lights up and displays white light.

[0073] Example 2

[0074] Based on the scheme of Example 1, this embodiment further provides a device for matching the solid line length of road markings in the ramp weaving area, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for adjusting the road markings in the ramp weaving area based on flow monitoring as in Example 1 is executed; thereby, the method for adjusting the solid line length of road markings in the ramp weaving area based on the input main road traffic flow X is realized. t and ramp traffic volume Y t , output the optimal solid line segment marking length Z corresponding to the current traffic scene L .

[0075] The device for matching the solid line length of the road marking in the ramp interweaving area provided in this embodiment is essentially a computer device for implementing the solution in Embodiment 1, and is used to dynamically adjust the display state of the controllable marking assembly according to the detection data received from the vehicle flow detection device. In practical applications, the computer device can be an embedded device installed at the controllable marking assembly, or a computer device installed in the backend server of the traffic control department, and communicates with the vehicle flow detection device and the controllable marking assembly in front.

[0076] In this embodiment, the computer device can be an intelligent terminal capable of executing programs, a tablet computer, a laptop computer, a desktop computer, a rack server, a blade server, a tower server or a cabinet server (including an independent server or a server cluster composed of multiple servers), etc.

[0077] The computer device indicated in this embodiment includes at least but is not limited to: a memory and a processor that can be connected to each other through a system bus. Among them, the memory (i.e., a readable storage medium) includes a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., an SD or DX memory, etc.), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a disk, an optical disk, etc. In some embodiments, the memory can be an internal storage unit of a computer device, such as a hard disk or a memory of the computer device. In other embodiments, the memory can also be an external storage device of a computer device, such as a plug-in hard disk equipped on the computer device, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), etc. Of course, the memory can also include both the internal storage unit of the computer device and its external storage device. In this embodiment, the memory is generally used to store an operating system and various application software installed on the computer device. In addition, the memory can also be used to temporarily store various types of data that have been output or are to be output.

[0078] The processor may be a central processing unit (CPU), a graphics processing unit (GPU), a controller, a microcontroller, a microprocessor, or other data processing chips in some embodiments. The processor is generally used to control the overall operation of a computer device. In this embodiment, the processor is used to run program codes stored in a memory or process data.

[0079] Example 3

[0080] On the basis of Examples 1 and 2, Figure 4 As shown, this embodiment further provides a ramp weaving area traffic management system, which includes: two sets of vehicle flow detection equipment, a set of controllable marking components and a controller. The controller communicates wirelessly with the vehicle flow detection equipment via a 5G communication network, and communicates wirelessly with the controllable marking components via WIFI.

[0081] Among them, two sets of traffic flow detection equipment are installed on the main road and ramp upstream of the ramp interweaving area. The traffic flow detection equipment includes a camera and a data processing module at the back end. The camera is used to capture real-time images of the designated sampling area on the road; the data processing module obtains the video data collected by the camera and detects the vehicles appearing in it based on the target recognition algorithm and the target tracking algorithm; then the total number of vehicles passing through the sampling area within the specified detection period is counted, and then the traffic flow in the designated sampling area is calculated based on the total number of vehicles and the duration of the detection period.

[0082] Specifically, in a vehicle detection device implemented based on a DSP processor, after receiving the road traffic picture taken by the camera, the DSP processor first sets a virtual coil at the same position of each frame of the image, the length of which is the sum of the lane widths contained in the picture taken by the camera, and the width is 1 / 2 of the length of the minimum vehicle model to be tested, and the virtual coil is set to black, that is, the pixel value of the virtual coil is 0. Then, the image is grayed by using the weighted average method; the image after graying is smoothed and denoised by using the Gaussian filter method; the image is binarized by using the maximum inter-class method to effectively separate the foreground target from the background image, and the pixel value is 255, that is, the foreground vehicle image is displayed in white. Then, the binary image is processed by mathematical morphology to obtain the bounding rectangle of the foreground target, while ensuring the accuracy of extracting the moving foreground target. Then, the centroid coordinates of the foreground target are calculated based on the bounding rectangle of the foreground target to obtain the motion trajectory of the foreground target. Finally, if the centroid of a foreground target in the current frame is within the virtual wireframe, and the centroid of the foreground target in the previous frame is outside the dotted frame, it means that a vehicle has entered the position represented by the virtual wireframe, and the traffic volume is increased by 1. Continue to use the same strategy to count multiple consecutive frames of images, and you can get the total traffic volume within the specified detection period.

[0083] The controllable marking assembly uses an embedded LED light strip installed at the lane dividing line. If the lamp beads at the specified position in the LED light strip emit white light, it means that this section has a mark, and if the lamp beads at the specified position are off, it means that this section has no road markings. The LED light strip simulates the solid line markings that are prohibited from crossing and the dotted line markings that are allowed to cross by controlling all or intermittent lighting of the LED lamp beads in the specified interval.

[0084] The controller includes a solid line length matching device for the road markings in the ramp interweaving area in Example 2, and a light strip control unit. The solid line length matching device is used to output the optimal solid line segment marking length corresponding to the current traffic scene according to the main road traffic volume and ramp traffic volume detected by the traffic volume detection device. The light strip control unit is used to control the controllable marking component to display a solid line at a specified length upstream of the inner and outer lane dividing lines of the main road in the interweaving area according to the optimal solid line segment marking length, and display a dotted line for the remaining part.

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for adjusting road markings in ramp weaving areas based on flow monitoring, characterized in that: It is used to dynamically adjust the length of the solid line segment marking between the middle lane and the outer lane of the main road in the interweaving area of ​​the main road and the ramp according to the traffic volume of the main road and the ramp; It includes the following steps: S1: Divide the traffic flow into several intervals, and then establish multiple different traffic scenarios corresponding to the main road and ramp in each traffic flow interval; S2: Use the traffic simulation system to simulate the vehicle traffic efficiency in various traffic scenarios, and solve the corresponding solid line segment marking length that can achieve the maximum traffic efficiency; S3: Based on the analysis results of the previous step, establish a characterization of any main road traffic flow interval X p and ramp traffic flow interval Y p The corresponding decision function Z of the ideal solid line segment length p : Z p =f(X p ,Y p ); S4: The traffic flow detection device installed upstream of the road in the direction of traffic flow detects the main road traffic flow X in the weaving area in real time within the specified detection period. t and ramp traffic volume Y t ; Then according to the decision function Z p Determine the ideal solid line segment length Z for the current period opt (X t , Y t ); S5: query the length specifications of the blank part and the marked part of the dotted line segment in the current road marking according to the current road grade; and convert the calculated ideal solid line segment marking length Z into opt (X t , Y t ) is converted into an optimal solid line segment length Z that meets the length specification L ; S6: According to the converted optimal solid line segment marking length Z L , adjust the display status of the controllable marking assembly installed between the middle lane and the outer lane of the main road in the weaving area.

2. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 1, characterized in that: In step S1 , assuming that the main road traffic flow is divided into m intervals and the ramp traffic flow is divided into n intervals, m×n different traffic scenarios can be established according to different combinations of the main road and ramp traffic flow intervals.

3. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 1, characterized in that: In step S2, the traffic simulation system includes TrafficGPT, SUMO, TESS NG, PTV VISSIM, Paramics, AIMSUN, Transmodeler, Trafficware, and Cube Dynasim.

4. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 1, characterized in that: In step S4, the vehicle flow detection device includes a camera and a data processing module at the back end thereof, and the method for realizing traffic flow monitoring is as follows: The camera captures real-time images of a designated sampling area on the road; the data processing module obtains the video data collected by the camera and detects vehicles appearing therein based on a target recognition algorithm and a target tracking algorithm; Then, the total number of vehicles passing through the sampling area within the specified detection period is counted, and the real-time traffic flow on the road is calculated based on the total number of vehicles and the duration of the detection period.

5. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 1, characterized in that: In step S4, the decision function Z opt (X t ,Y t ) is as follows: In the above formula, u and v represent the lengths of the one-dimensional vectors representing the main road traffic flow and ramp traffic flow, respectively.

6. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 1, characterized in that: In step S5, the expression of the conversion function is as follows: In the above formula, L s Indicates the length of the marked portion of the dashed line segment of the inner and outer lanes of the main road in the ramp weaving area that meets the current road grade specifications; L d It indicates the length of the blank part in the dashed line segment of the inner and outer lanes of the main road in the ramp weaving area that meets the current road grade specifications.

7. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 6, characterized in that: In the city expressway, L s =600cm, L d =900cm.

8. The method for adjusting road markings in ramp weaving areas based on flow monitoring according to claim 1, characterized in that: In step S6, the controllable marking assembly uses an embedded LED light strip installed at the lane dividing line; if the lamp beads at the specified position in the LED light strip emit white light, it means that this section has a mark, and if the lamp beads at the specified position are off, it means that this section has no road markings; the LED light strip simulates the solid line marks that are prohibited from crossing and the dotted lines that are allowed to cross in the road by controlling all the LED lamp beads in the specified interval to light up or light up intermittently.

9. A device for matching the solid line length of road markings in a ramp weaving area, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for adjusting the road markings in the ramp weaving area based on flow monitoring according to any one of claims 1 to 8 is executed; thereby realizing the adjustment of the road markings in the ramp weaving area based on the input main road traffic flow X t and ramp traffic volume Y t , output the optimal solid line segment marking length Z corresponding to the current traffic scene L .

10. A ramp weaving area traffic management system, characterized by: It includes: Two sets of vehicle flow detection equipment, which are respectively installed on the main road and the ramp upstream of the ramp interweaving area; the vehicle flow detection equipment includes a camera and a data processing module at the back end thereof; The camera is used to capture real-time images of a designated sampling area on the road; the data processing module obtains the video data collected by the camera and detects vehicles appearing therein based on a target recognition algorithm and a target tracking algorithm; Then, the total number of vehicles passing through the sampling area within the specified detection period is counted, and the traffic volume within the specified sampling area is calculated based on the total number of vehicles and the duration of the detection period; The controllable marking assembly adopts an LED light strip embedded and installed at the lane dividing line; if the lamp beads at the designated position of the LED light strip emit white light, it means that this section has a mark, and if the lamp beads at the designated position are off, it means that this section has no road markings; the LED light strip simulates the solid line markings that are prohibited from crossing and the dotted line markings that are allowed to cross on the road by controlling all the LED lamp beads in the designated section to light up or light up intermittently; A controller, comprising a solid line length matching device for road markings in a ramp weaving area as claimed in claim 9, and a light strip control unit; the solid line length matching device is used to output an optimal solid line segment marking length corresponding to the current traffic scene according to the main road traffic volume and ramp traffic volume detected by a traffic flow detection device; the light strip control unit is used to control the controllable marking component to display a solid line at a specified length upstream of the inner and outer lane dividing lines of the main road in the weaving area according to the optimal solid line segment marking length, and display a dotted line for the remaining part.

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