Event-driven high expressway ramp control method and device and electronic equipment

Abstract

The invention provides an event-driven high-speed road ramp control method and device and electronic equipment, and the method comprises the steps: obtaining historical vehicle data, determining a first speed, a second speed and a blocking density corresponding to a preset time period according to the historical vehicle data, further determining at least one lamp control time period in the preset time period, if the current time period belongs to the lamp control time period, the current speed, the current density and the current queuing length are obtained, a first green time ratio and a second green time ratio are determined, the current speed is compared with the first speed and the second speed, and the current queuing length is compared with a preset queuing threshold value; and according to the comparison result, the first green time ratio, the second green time ratio and a preset maximum green time ratio, determining a target green time ratio, and according to the target green time ratio, carrying out high-speed road ramp passage control. According to the method, the ramp passage is controlled according to the real-time data, the maneuverability is high, and the occurrence of the congestion phenomenon of the high-speed road ramp is greatly reduced.

Description

Technical Field

[0001] The present application relates to the field of traffic control technology, and in particular to an event-driven high-speed road ramp control method, device and electronic equipment. Background Art

[0002] Smart cities use advanced information technology and communication technology to achieve intelligent management and operation of cities. Traffic management is a key area of ​​focus for smart cities. With the development of society, high-speed ramps are prone to congestion, especially during certain periods such as rush hour. Therefore, how to solve the traffic congestion phenomenon on high-speed ramps has become an urgent problem to be solved.

[0003] Currently, the ramps of expressways are usually controlled according to a timing control strategy, that is, a fixed control method is used in a fixed time period.

[0004] However, the timing control strategy cannot be adjusted according to the real-time traffic status, has poor maneuverability, and long-term congestion will still occur. Summary of the invention

[0005] The purpose of this application is to provide an event-driven high-speed road ramp control method, device and electronic equipment to address the shortcomings of the above-mentioned prior art, so as to solve the problems of poor maneuverability and easy congestion in the prior art.

[0006] To achieve the above objectives, the technical solutions adopted in this application are as follows:

[0007] In a first aspect, the present application provides an event-driven high-speed road ramp control method, the method comprising:

[0008] Acquire historical vehicle data, wherein the historical vehicle data includes speed average, density average and flow sum;

[0009] Determine a first speed, a second speed and a congestion density corresponding to a preset time period according to the historical vehicle data, and determine at least one light control period within the preset time period according to the first speed and the speed average, wherein the first speed is the critical vehicle speed average for starting congestion, and the second speed is the critical vehicle speed when there is a vehicle that cannot move forward on the ramp;

[0010] If the current time period belongs to the light control time period, the current speed, current density and current queue length corresponding to the current time period are obtained, and a first green-to-signal ratio of the current time period is determined according to the current density and the blocking density, and a second green-to-signal ratio of the current time period is determined according to the current queue length;

[0011] The current speed and the first speed and the second speed are compared to obtain a first comparison result, and the current queue length is compared with a preset queue threshold to obtain a second comparison result, and a target green-to-signal ratio is determined based on the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio and the preset maximum green-to-signal ratio, and high-speed road ramp traffic control is performed based on the target green-to-signal ratio.

[0012] Optionally, determining the first speed, the second speed and the blocking density corresponding to the preset time period according to the historical vehicle data, and determining at least one light control period within the preset time period according to the first speed and the speed mean, comprises:

[0013] Determine the maximum flow and the blocking density according to the historical vehicle data, use the speed value corresponding to the maximum flow as the first speed, and use the speed value corresponding to the blocking density as the second speed;

[0014] The time period in which the average speed in the preset time period is less than or equal to the first speed is used as the candidate time period;

[0015] Determine whether the duration of each of the selected time periods is greater than a preset duration;

[0016] If yes, then determine in sequence whether the time intervals of adjacent selected time periods are less than the preset time length;

[0017] If yes, the adjacent time periods to be selected and the corresponding time intervals are combined into one light control time period; if no, the adjacent time periods to be selected are each taken as one light control time period.

[0018] Optionally, determining the maximum flow rate and the blocking density according to the historical vehicle data includes:

[0019] Input the velocity mean and density mean into the velocity-density relationship to calculate the blocking density;

[0020] The total flow rate and the mean density are input into the flow-density relationship to calculate the maximum flow rate.

[0021] Optionally, determining a first green-to-signal ratio in a current period according to the current density and the blocking density includes:

[0022] Determine current occupancy based on current density;

[0023] Calculating a difference between a preset critical occupancy rate and the current occupancy rate, and taking a product of the difference and a preset calibration parameter as a first intermediate value;

[0024] The sum of the first green-to-signal ratio of the previous period of the current period and the first intermediate value is used as the first green-to-signal ratio of the current period.

[0025] Optionally, determining a second green-to-signal ratio for a current period according to the current queue length includes:

[0026] Calculate the quotient of the current queue length and the queue threshold, and take the difference between the quotient and 1 as the second intermediate value;

[0027] The product of the second intermediate value and the preset ramp queue adjustment rate is used as the third intermediate value;

[0028] The sum of the second green-to-signal ratio of the previous period of the current period and the third intermediate value is used as the second green-to-signal ratio of the current period.

[0029] Optionally, determining a target green-to-signal ratio according to the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio, and a preset maximum green-to-signal ratio includes:

[0030] If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is less than or equal to the queue threshold, determining a first minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio, and using the first minimum value as the target green-to-signal ratio;

[0031] If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is greater than the queue threshold, determining a maximum value between the first green-to-signal ratio and the second green-to-signal ratio, and determining a second minimum value between the maximum value and the maximum green-to-signal ratio, and using the second minimum value as the target green-to-signal ratio;

[0032] If the first comparison result indicates that the current speed is not greater than the second speed, a third minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio is determined, and the third minimum value is used as a target green-to-signal ratio.

[0033] Optionally, the performing high-speed road ramp traffic control according to the target green-to-signal ratio includes:

[0034] Comparing the green-to-signal ratios in each pre-established ramp control scheme according to the target green-to-signal ratio, taking the ramp control scheme corresponding to the green-to-signal ratio with the smallest difference between the target green-to-signal ratio and the green-to-signal ratio as the target ramp control scheme, wherein the ramp control scheme includes the green-to-signal ratio and the ramp light control strategy;

[0035] According to the ramp light control strategy in the target ramp control scheme, the high-speed road ramp traffic control is performed. In the second aspect, the present application provides an event-driven high-speed road ramp control device, the device comprising:

[0036] An acquisition module, used to acquire historical vehicle data, wherein the historical vehicle data includes a speed average, a density average, and a flow sum;

[0037] A first determination module is used to determine a first speed, a second speed and a congestion density corresponding to a preset time period according to the historical vehicle data, and to determine at least one light control period within the preset time period according to the first speed and the speed average, wherein the first speed is the critical vehicle speed average for starting congestion, and the second speed is the critical vehicle speed when there is a vehicle that cannot move forward on the ramp;

[0038] a second determination module, configured to obtain a current speed, a current density, and a current queue length corresponding to the current time period if the current time period belongs to a light-controlled time period, and determine a first green-to-signal ratio of the current time period according to the current density and the blocking density, and determine a second green-to-signal ratio of the current time period according to the current queue length;

[0039] A control module is used to compare the current speed with the first speed and the second speed to obtain a first comparison result, and compare the current queue length with a preset queue threshold to obtain a second comparison result, determine a target green-to-signal ratio based on the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio and a preset maximum green-to-signal ratio, and perform high-speed road ramp traffic control based on the target green-to-signal ratio.

[0040] Optionally, the first determining module is specifically configured to:

[0041] Determine the maximum flow and the blocking density according to the historical vehicle data, use the speed value corresponding to the maximum flow as the first speed, and use the speed value corresponding to the blocking density as the second speed;

[0042] The time period in which the average speed in the preset time period is less than or equal to the first speed is used as the candidate time period;

[0043] Determine whether the duration of each of the selected time periods is greater than a preset duration;

[0044] If yes, then determine in sequence whether the time intervals of adjacent selected time periods are less than the preset time length;

[0045] If yes, the adjacent time periods to be selected and the corresponding time intervals are combined into one light control time period; if no, the adjacent time periods to be selected are each taken as one light control time period.

[0046] Optionally, the first determining module is specifically configured to:

[0047] Input the velocity mean and density mean into the velocity-density relationship to calculate the blocking density;

[0048] The total flow rate and the mean density are input into the flow-density relationship to calculate the maximum flow rate.

[0049] Optionally, the second determining module is specifically configured to:

[0050] Determine current occupancy based on current density;

[0051] Calculating a difference between a preset critical occupancy rate and the current occupancy rate, and taking a product of the difference and a preset calibration parameter as a first intermediate value;

[0052] The sum of the first green-to-signal ratio of the previous period of the current period and the first intermediate value is used as the first green-to-signal ratio of the current period.

[0053] Optionally, the second determining module is specifically configured to:

[0054] Calculate the quotient of the current queue length and the queue threshold, and take the difference between the quotient and 1 as the second intermediate value;

[0055] The product of the second intermediate value and the preset ramp queue adjustment rate is used as the third intermediate value;

[0056] The sum of the second green-to-signal ratio of the previous period of the current period and the third intermediate value is used as the second green-to-signal ratio of the current period.

[0057] Optionally, the control module is specifically used for:

[0058] If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is less than or equal to the queue threshold, determining a first minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio, and using the first minimum value as the target green-to-signal ratio;

[0059] If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is greater than the queue threshold, determining a maximum value between the first green-to-signal ratio and the second green-to-signal ratio, and determining a second minimum value between the maximum value and the maximum green-to-signal ratio, and using the second minimum value as the target green-to-signal ratio;

[0060] If the first comparison result indicates that the current speed is not greater than the second speed, a third minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio is determined, and the third minimum value is used as a target green-to-signal ratio.

[0061] Optionally, the control module is specifically used to:

[0062] Comparing the green-to-signal ratios in each pre-established ramp control scheme according to the target green-to-signal ratio, taking the ramp control scheme corresponding to the green-to-signal ratio with the smallest difference between the target green-to-signal ratio and the green-to-signal ratio as the target ramp control scheme, wherein the ramp control scheme includes the green-to-signal ratio and the ramp light control strategy;

[0063] Carry out traffic control on the expressway ramp according to the ramp light control strategy in the target ramp control plan.

[0064] In a third aspect, the present application provides an electronic device comprising: a processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the storage medium via the bus, and the processor executes the machine-readable instructions to perform the steps of the event-driven expressway ramp control method as described above.

[0065] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the event-driven high-speed road ramp control method as described above are executed.

[0066] The beneficial effects of the present application are: by determining the first speed, the second speed and the congestion density based on historical vehicle data, the critical values ​​under various traffic congestion conditions are determined, and then at least one light control period within a preset time period is determined based on the first speed and the speed average, and real-time data acquisition and ramp traffic control are performed based on the light control period, thereby reducing the amount of data acquisition and further reducing the amount of calculation for determining the target green-to-signal ratio. Then, the first green-to-signal ratio and the second green-to-signal ratio are determined based on the real-time data, and the target green-to-signal ratio is determined based on the comparison of the current speed with the first speed and the second speed, and the current queue length with the queue threshold, so as to control the ramp traffic of the expressway based on the target green-to-signal ratio. The present application compares the real-time acquired data with the critical values ​​and queue thresholds under various congestion conditions, and adjusts the ramp control strategy in real time according to the comparison results. It has strong mobility and greatly reduces the occurrence of congestion on the ramps of expressways. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0068] Figure 1 This is a schematic diagram of an application scenario of an event-driven high-speed road ramp control method provided in an embodiment of the present application;

[0069] Figure 2 It is a flow chart of an event-driven high-speed road ramp control method provided in an embodiment of the present application;

[0070] Figure 3 It is a flowchart of a method for determining at least one light control period within a preset time period provided by an embodiment of the present application;

[0071] Figure 4 is a flow chart of a method for determining a first green-to-signal ratio provided in an embodiment of the present application;

[0072] Figure 5 This is a flow chart of a method for determining a target green-to-signal ratio provided in an embodiment of the present application;

[0073] Figure 6 It is a structural schematic diagram of an event-driven high-speed road ramp control device provided in an embodiment of the present application;

[0074] Figure 7 It is a structural schematic diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0075] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart under the guidance of the content of the present application, or remove one or more operations from the flowchart.

[0076] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0077] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the existence of the features declared thereafter, but does not exclude the addition of other features.

[0078] In the prior art, the ramps of expressways are usually controlled according to a timing control strategy, but the timing control strategy cannot be adjusted according to the real-time traffic status, has poor maneuverability, and long-term congestion will still occur.

[0079] Based on this, the present application proposes an event-driven high-speed road ramp control method, which determines the first speed, the second speed and the congestion density within a preset time period based on historical vehicle data, and then determines at least one light-controlled period within the preset time period. If the current period belongs to the light-controlled period, the current speed, the current density and the current queue length are obtained, and the first green-to-signal ratio and the second green-to-signal ratio are determined based on the above data, so as to determine the green-to-signal ratio under different ramp conditions to cope with different congestion phenomena. Then the current speed is compared with the first speed and the second speed, and the current queue length is compared with the preset queue threshold. According to the above comparison results and the first green-to-signal ratio, the second green-to-signal ratio and the preset maximum green-to-signal ratio, the target green-to-signal ratio is determined, so as to control the high-speed road ramp traffic. This method can be adjusted according to the real-time traffic status, has strong mobility, and greatly reduces the occurrence of congestion on the high-speed road ramp.

[0080] Before introducing the event-driven high-speed road ramp control method, the usage scenarios of the method are first introduced. Figure 1 Schematic diagram of an application scenario of an event-driven high-speed road ramp control method provided in an embodiment of the present application. Figure 1 As shown, the event-driven high-speed road ramp control method can be applied to an electronic device with computing capabilities, which can be connected to detection devices such as visual detectors and millimeter-wave radars installed in the main line, ramps, and merging areas of the high-speed road, so as to obtain real-time information such as vehicle flow, vehicle speed, and vehicle type. The electronic device can also be connected to a control device, which can be a traffic light located on the ramp. After the electronic device determines the target green-to-signal ratio, it can obtain a ramp light control strategy, thereby controlling the display time of each signal light in the traffic light based on the ramp control strategy. As an optional implementation, the electronic device can also be connected to a display device, which is used to display the current congestion status to people located on the high-speed road ramp.

[0081] Figure 2 is a flow chart of an event-driven high-speed road ramp control method provided in an embodiment of the present application. Figure 2 The specific process of event-driven expressway ramp control method is introduced.

[0082] S201. Obtain historical vehicle data, where the historical vehicle data includes speed average, density average and flow total.

[0083] As an optional implementation, historical vehicle data may be acquired according to a preset data acquisition period. The shorter the preset data acquisition period, the more frequent the ramp control. Exemplarily, the preset data acquisition period may be 5 minutes.

[0084] Furthermore, the speed mean may be the mean of the speeds of the vehicles detected by the detection device during the preset data acquisition period. Density may be the density of vehicles on a lane, that is, the number of vehicles per unit length on a lane at a certain moment. The density mean may be the mean of the density during the preset data acquisition period. The flow sum may be the number of vehicles passing through a certain point on the road or a certain lane during the preset data acquisition period. In this embodiment, the unit of the flow sum is vehicles per hour.

[0085] S202. Determine a first speed, a second speed, and a congestion density corresponding to a preset time period based on historical vehicle data, and determine at least one light control period within the preset time period based on the first speed and the speed average, wherein the first speed is the critical vehicle speed average for starting congestion, and the second speed is the critical vehicle speed when there is a vehicle that cannot move forward on the ramp.

[0086] The first speed may be the speed corresponding to the maximum flow rate on the current lane, which indicates that the current lane is beginning to be blocked. The second speed may be the speed corresponding to the blocking density, which is the vehicle density on the current lane when the blocking occurs.

[0087] Optionally, the preset time period may be a time period with a certain regularity. As an example, the preset time period may be a time period between 0:00 and 24:00. As another example, the preset time period may be from the start time of a working day to the start time of a holiday, and other times.

[0088] The preset time period can be divided into a light-controlled time period and a non-light-controlled time period. Among them, the light-controlled time period can be a time period when congestion begins to occur, and the non-light-controlled time period can be a time period for smooth travel. The light-controlled time period within the preset time period can be determined according to the first speed and the speed average obtained in each preset data acquisition period, and the remaining time periods are non-light-controlled time periods. This application mainly performs ramp traffic control for the light-controlled time period, including obtaining real-time data and determining the target green-signal ratio according to the real-time data.

[0089] It is worth noting that the preset time period, the preset data acquisition period and the light control period have the following relationship: the preset time period is greater than the light control period and greater than the preset data acquisition period. Specifically, the preset time period may include at least one light control period, and multiple preset data acquisition periods may be divided in each light control period to acquire real-time data. Exemplarily, the preset time period may be from 0:00 to 24:00, the light control period may be from 6:00 to 8:00, 11:00 to 3:00 and 5:00 to 7:00, and the preset data acquisition period may be 5 minutes.

[0090] S203. If the current time period belongs to the light-controlled time period, obtain the current speed, current density and current queue length corresponding to the current time period, and determine the first green-to-signal ratio of the current time period according to the current density and blocking density, and determine the second green-to-signal ratio of the current time period according to the current queue length.

[0091] As an optional implementation, the current time period may be a preset data acquisition time period. If the preset data acquisition time period is 5 minutes, the current speed, current density and current queue length 5 minutes before the current moment are acquired. Among them, the current data may be the current speed mean, the current density may be the current density mean, and the current queue length may be detected by a detection device.

[0092] It is worth noting that the current speed, current density and current queue length corresponding to the current time period are data within the preset data acquisition period before the current time point, and the first green-to-signal ratio and the second green-to-signal ratio of the current time period are the time period after the current time point, and the length of the time period can be equal to the preset data acquisition period.

[0093] Among them, the green-to-signal ratio is the proportion of time that can be used for vehicle traffic in a traffic light cycle. In this application, the first green-to-signal ratio is the green-to-signal ratio calculated under non-serious congestion conditions. Severe congestion can be determined by whether the current queue length exceeds the preset queue threshold. The second green-to-signal ratio is the green-to-signal ratio calculated under severe congestion conditions. When the current queue length exceeds the preset queue threshold, it is a severe congestion.

[0094] S204. Compare the current speed with the first speed and the second speed to obtain a first comparison result, and compare the current queue length with a preset queue threshold to obtain a second comparison result, determine the target green-to-signal ratio based on the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio and the preset maximum green-to-signal ratio, and perform high-speed road ramp traffic control based on the target green-to-signal ratio.

[0095] The first comparison result can be used to determine whether the current state is congested, and the second comparison result can be used to determine the severity of the current congestion. The first green-to-signal ratio, the second green-to-signal ratio, or the preset maximum green-to-signal ratio is selected as the target green-to-signal ratio based on whether the current state is congested and the severity of the current congestion.

[0096] As an optional implementation, since the target green-to-signal ratio is the proportion of vehicle traffic time in a cycle, that is, the green light time in a cycle can be determined according to the target green-to-signal ratio, and the green light display time can be allocated according to the traffic light strategy. For example, if the cycle time is 30 minutes and the green light time is 20 minutes, the green light time can be evenly divided into 4 5-minute periods evenly distributed within 30 minutes.

[0097] In this embodiment, by determining the first speed, the second speed and the congestion density based on historical vehicle data, the critical values ​​under various traffic congestion conditions are determined, and then at least one light control period within a preset time period is determined based on the first speed and the speed average, and real-time data acquisition and ramp traffic control are performed based on the light control period, thereby reducing the amount of data acquisition and further reducing the amount of calculation for determining the target green-to-signal ratio. Then, the first green-to-signal ratio and the second green-to-signal ratio are determined based on the real-time data, and the target green-to-signal ratio is determined based on the comparison of the current speed with the first speed and the second speed, and the current queue length with the queue threshold, so as to control the ramp traffic of the expressway based on the target green-to-signal ratio. This application compares the real-time acquired data with the critical values ​​and queue thresholds under various congestion conditions, and adjusts the ramp control strategy in real time according to the comparison results. It has strong mobility and greatly reduces the occurrence of congestion on the ramps of expressways.

[0098] Figure 3 is a flow chart of a method for determining at least one light control period within a preset time period provided by an embodiment of the present application. Figure 3 The specific steps of determining at least one light control period within the preset time period in the above step S202 are introduced as follows:

[0099] S301. Determine the maximum flow and the congestion density according to historical vehicle data, use the speed value corresponding to the maximum flow as the first speed, and use the speed value corresponding to the congestion density as the second speed.

[0100] The maximum flow rate is the maximum flow rate within the preset data acquisition period.

[0101] S302: select a time period in which the speed average value within the preset time period is less than or equal to the first speed as a candidate time period.

[0102] Among them, within the preset time period, if the average speed is less than or equal to the first speed, it means that the current scene is in a blocking phenomenon.

[0103] S303: Determine whether the duration of each time period to be selected is greater than a preset duration.

[0104] Optionally, the preset duration may be a shorter period of time, for example, the preset duration may be set to 5 minutes.

[0105] S304: If yes, determine in sequence whether the time intervals between adjacent time periods to be selected are less than a preset duration.

[0106] Optionally, if the duration of the waiting time period is less than the preset duration, it means that the waiting time period is a short period, and real-time data acquisition and ramp traffic control may not be performed during this period. This method can abandon the waiting time period that is too short, thereby improving control efficiency.

[0107] S305: If yes, then the adjacent time periods to be selected and the corresponding time intervals are combined into one light control time period; if no, then the adjacent time periods to be selected are each used as one light control time period.

[0108] Optionally, if the time interval between adjacent waiting time periods is less than a preset time length, it means that the time interval between the two waiting time periods is not long, and the time interval between the adjacent waiting time periods can be used as a part of the light control time period.

[0109] For example, if the preset duration is 5 minutes, there are 4 time periods to be selected between 1pm and 3pm, namely 1pm to 1pm 2pm, 1pm 40pm to 2pm, 2pm 3pm to 2pm 2pm, and 2pm 50pm to 3pm. Then filter out the time period from 1pm to 1pm 2pm, and determine whether the time intervals between 1pm to 2pm, 2pm 3pm to 2pm 2pm, 2pm 3pm to 2pm 2pm, and 2pm 50pm to 3pm are less than the preset duration. Since the time intervals between 1pm to 2pm and 2pm 3pm to 2pm 2pm are less than the preset duration, 1pm to 2pm and 2pm 3pm to 2pm 2pm are merged into 1pm to 2pm 2pm as a light control time period.

[0110] In this embodiment, the blocking density, the first speed and the second speed are obtained by calculation, and the selected time period is determined according to the preset time period, and it is determined whether the duration of the selected time period is greater than the preset duration, and the selected time period less than the preset duration is filtered, thereby improving the calculation efficiency. Then, it is determined in turn whether the time intervals of adjacent selected time periods are less than the preset duration, so as to merge the selected time periods with small time intervals, thereby further improving the calculation efficiency and simplifying the control process.

[0111] Furthermore, the specific method for determining the maximum flow rate and the blocking density according to the historical vehicle data in the above step S301 is as follows:

[0112] Optionally, the speed mean and the density mean are input into the speed-density relationship to calculate the blocking density. The flow sum and the density mean are input into the flow-density relationship to calculate the maximum flow.

[0113] The velocity density relationship can be as follows:

[0114]

[0115] Where v is the mean velocity, v f is the free-flow speed, k is the mean density, k j is the blocking density. Among them, the free-flowing speed is the critical speed when the vehicle is free-flowing. By fitting formula (1), the free-flowing speed and blocking density can be obtained.

[0116] The flow density relationship can be expressed as follows:

[0117] q=kv (2)

[0118] Among them, q is the total flow, k is the density mean, and v is the velocity mean. By fitting formula (2), the maximum flow can be obtained.

[0119] In this embodiment, the blocking density and the maximum flow are calculated by using the speed density relationship and the flow density relationship, so that the extreme values ​​of the density and the flow can be obtained, and then the first speed and the second speed can be obtained.

[0120] Figure 4 This is a flow chart of a method for determining a first green-to-signal ratio provided in an embodiment of the present application. Figure 4 The specific method for determining the first green-to-signal ratio of the current period according to the current density and the blocking density in the above step S203 is introduced.

[0121] S401. Determine the current occupancy rate according to the current density.

[0122] Optionally, the current occupancy rate may be determined according to the following formula (3):

[0123]

[0124] Among them, ρ is the current occupancy rate, k is the density mean, and the average vehicle length can be calculated through the data collected by the detection equipment.

[0125] S402: Calculate a difference between a preset critical occupancy rate and a current occupancy rate, and use a product of the difference and a preset calibration parameter as a first intermediate value.

[0126] S403: taking the sum of the first green-to-signal ratio of the previous period of the current period and the first intermediate value as the first green-to-signal ratio of the current period.

[0127] Specifically, the formula for calculating the first green-to-signal ratio may be as follows:

[0128]

[0129] Wherein, γ(k) is the first green-to-signal ratio, γ(k-1) is the first green-to-signal ratio of the previous period of the current period, and K is a preset calibration parameter. For example, K may be 70. is the preset critical occupancy, is the current occupancy.

[0130] It is worth noting that the first green-to-signal ratio of the initial period can be preset.

[0131] Next, the method of determining the second green-to-signal ratio of the current time period according to the current queue length in the above step S203 is introduced.

[0132] Optionally, the quotient of the current queue length and the queue threshold is calculated, and the difference between the quotient and 1 is used as the second intermediate value. The product of the second intermediate value and the preset ramp queue adjustment rate is used as the third intermediate value. The sum of the second green-to-signal ratio of the previous time period of the current time period and the second intermediate value is used as the second green-to-signal ratio of the current time period.

[0133] Specifically, the formula for calculating the second green-to-signal ratio may be as follows:

[0134]

[0135] Among them, w(k) is the second green-to-signal ratio of the current period, w(k-1) is the second green-to-signal ratio of the previous period of the current period, K q is the ramp queue adjustment rate, l k-1 is the current queue length, It is the queue threshold, which can be configured according to the actual queue situation.

[0136] It is worth noting that the first green-to-signal ratio of the initial period can be preset.

[0137] In this embodiment, the current occupancy is calculated, and then the first green-to-signal ratio of the current period is calculated based on the preset critical occupancy, the current occupancy, and the first green-to-signal ratio of the previous period of the current period, and the second green-to-signal ratio of the current moment is determined based on the second green-to-signal ratio of the previous period of the current period, the ramp queue adjustment rate, the current queue length, and the queue threshold. Based on this, two green-to-signal ratios are determined according to the real-time situation of the expressway ramp to cope with different scenarios.

[0138] Figure 5 It is a flow chart of a method for determining a target green-to-signal ratio provided in an embodiment of the present application.

[0139] Specifically, the application methods of the first green-to-signal ratio and the second green-to-signal ratio based on different scenarios are as follows:

[0140] S501. If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is less than or equal to the queue threshold, determine the first minimum value between the first green-to-letter ratio and the maximum green-to-letter ratio, and use the first minimum value as the target green-to-letter ratio.

[0141] Optionally, if the current speed is less than the first speed and greater than the second speed, it means that the current ramp scene is congested, but vehicles can still pass smoothly. If the current queue length is less than or equal to the queue threshold, it means that the current congestion is not serious.

[0142] Optionally, the preset maximum green-to-signal ratio can be set by the user according to actual conditions. The smaller the maximum green-to-signal ratio is, the shorter the green light time is.

[0143] S502. If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is greater than the queue threshold, then determine the maximum value between the first green-to-signal ratio and the second green-to-signal ratio, and determine the second minimum value between the maximum value and the maximum green-to-signal ratio, and use the second minimum value as the target green-to-signal ratio.

[0144] Optionally, if the current queue length is greater than the queue threshold, it indicates that the current congestion situation is serious.

[0145] S503: If the first comparison result indicates that the current speed is not greater than the second speed, determine the third minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio, and use the third minimum value as the target green-to-signal ratio.

[0146] Optionally, if the current speed is not greater than the second speed, it indicates that the vehicle is currently in a congested state and some vehicles cannot pass smoothly.

[0147] In this embodiment, through the first comparison result and the second comparison result, the first green-to-signal ratio and the second green-to-signal ratio are selected to take the one with the maximum green-to-signal ratio as the target green-to-signal ratio, so as to determine which green-to-signal ratio calculation method to select according to the actual ramp conditions, and then more accurately obtain the target green-to-signal ratio through real-time data calculation.

[0148] As an optional implementation, the specific method for performing high-speed road ramp traffic control according to the target green-to-signal ratio in the above step S204 is as follows:

[0149] Optionally, the target green-to-signal ratio is compared with the green-to-signal ratios in the pre-established ramp control schemes, and the ramp control scheme corresponding to the green-to-signal ratio with the smallest difference between the target green-to-signal ratio and the green-to-signal ratio is taken as the target ramp control scheme, and the ramp control scheme includes the green-to-signal ratio and the ramp light control strategy.

[0150] A ramp control database may be pre-established, and the ramp control database includes multiple ramp control schemes, each of which includes a corresponding green-to-signal ratio and a ramp light control strategy. The ramp light control strategy may be a green light time allocation frequency.

[0151] Optionally, the target green-to-signal ratio is subtracted from the green-to-signal ratio in each ramp control scheme, and the ramp control scheme corresponding to the green-to-signal ratio with the smallest difference is taken as the target ramp control scheme.

[0152] Optionally, the ramp traffic control on the expressway is performed according to the ramp light control strategy in the target ramp control scheme.

[0153] In this embodiment, the target ramp control scheme is determined by the target green-to-signal ratio, and the ramp light control strategy in the target ramp control scheme is used to finely control the traffic on the expressway ramp.

[0154] Based on the same inventive concept, an event-driven expressway ramp control device corresponding to the event-driven expressway ramp control method is also provided in the embodiment of the present application. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the above-mentioned event-driven expressway ramp control method in the embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0155] Reference Figure 6 FIG. 6 is a schematic diagram of the structure of an event-driven high-speed road ramp control device provided in an embodiment of the present application. The device includes: an acquisition module 601, a first determination module 602, a second determination module 603 and a control module 604, wherein:

[0156] An acquisition module 601 is used to acquire historical vehicle data, wherein the historical vehicle data includes a speed average, a density average, and a flow sum;

[0157] A first determination module 602 is used to determine a first speed, a second speed and a congestion density corresponding to a preset time period according to the historical vehicle data, and determine at least one light control period within the preset time period according to the first speed and the speed average, wherein the first speed is the critical vehicle speed average for starting congestion, and the second speed is the critical vehicle speed when there is a vehicle that cannot move forward on the ramp;

[0158] The second determination module 603 is used for obtaining the current speed, current density and current queue length corresponding to the current time period if the current time period belongs to the light control time period, and determining the first green-to-signal ratio of the current time period according to the current density and the blocking density, and determining the second green-to-signal ratio of the current time period according to the current queue length;

[0159] The control module 604 is used to compare the current speed with the first speed and the second speed to obtain a first comparison result, and compare the current queue length with a preset queue threshold to obtain a second comparison result, determine a target green-to-signal ratio based on the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio and the preset maximum green-to-signal ratio, and perform high-speed road ramp traffic control based on the target green-to-signal ratio.

[0160] Optionally, the first determining module 602 is specifically configured to:

[0161] Determine the maximum flow and the blocking density according to the historical vehicle data, use the speed value corresponding to the maximum flow as the first speed, and use the speed value corresponding to the blocking density as the second speed;

[0162] The time period in which the average speed in the preset time period is less than or equal to the first speed is used as the candidate time period;

[0163] Determine whether the duration of each of the selected time periods is greater than a preset duration;

[0164] If yes, then determine in sequence whether the time intervals of adjacent selected time periods are less than the preset time length;

[0165] If yes, the adjacent time periods to be selected and the corresponding time intervals are combined into one light control time period; if no, the adjacent time periods to be selected are each taken as one light control time period.

[0166] Optionally, the first determining module 602 is specifically configured to:

[0167] Input the velocity mean and density mean into the velocity-density relationship to calculate the blocking density;

[0168] The total flow rate and the mean density are input into the flow-density relationship to calculate the maximum flow rate.

[0169] Optionally, the second determining module 603 is specifically configured to:

[0170] Determine current occupancy based on current density;

[0171] Calculating a difference between a preset critical occupancy rate and the current occupancy rate, and taking a product of the difference and a preset calibration parameter as a first intermediate value;

[0172] The sum of the first green-to-signal ratio of the previous period of the current period and the first intermediate value is used as the first green-to-signal ratio of the current period.

[0173] Optionally, the second determining module 603 is specifically configured to:

[0174] Calculate the quotient of the current queue length and the queue threshold, and take the difference between the quotient and 1 as the second intermediate value;

[0175] The product of the second intermediate value and the preset ramp queue adjustment rate is used as the third intermediate value;

[0176] The sum of the second green-to-signal ratio of the previous period of the current period and the third intermediate value is used as the second green-to-signal ratio of the current period.

[0177] Optionally, the control module 604 is specifically configured to:

[0178] If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is less than or equal to the queue threshold, determining a first minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio, and using the first minimum value as the target green-to-signal ratio;

[0179] If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is greater than the queue threshold, determining a maximum value between the first green-to-signal ratio and the second green-to-signal ratio, and determining a second minimum value between the maximum value and the maximum green-to-signal ratio, and using the second minimum value as the target green-to-signal ratio;

[0180] If the first comparison result indicates that the current speed is not greater than the second speed, a third minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio is determined, and the third minimum value is used as a target green-to-signal ratio.

[0181] Optionally, the control module 604 is specifically configured to:

[0182] Comparing the green-to-signal ratios in each pre-established ramp control scheme according to the target green-to-signal ratio, taking the ramp control scheme corresponding to the green-to-signal ratio with the smallest difference between the target green-to-signal ratio and the green-to-signal ratio as the target ramp control scheme, wherein the ramp control scheme includes the green-to-signal ratio and the ramp light control strategy;

[0183] Carry out traffic control on the expressway ramp according to the ramp light control strategy in the target ramp control plan.

[0184] For descriptions of the processing flow of each module in the device and the interaction flow between each module, reference may be made to the relevant descriptions in the above method embodiment, which will not be described in detail here.

[0185] The present application also provides an electronic device, such as Figure 7 , which is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application, includes: a processor 701, a memory 702 and a bus. The memory 702 stores machine-readable instructions executable by the processor 701 (for example, Figure 6 In the device, the execution instructions corresponding to the acquisition module 601, the first determination module 602, the second determination module 603 and the control module 604 are obtained, etc. When the computer device is running, the processor 701 communicates with the memory 702 through a bus, and when the machine-readable instructions are executed by the processor 701, the above-mentioned event-driven high-speed road ramp control method is executed.

[0186] The embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned event-driven high-speed road ramp control method are executed.

[0187] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the method embodiment, and will not be repeated in this application. In the several embodiments provided in this application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0188] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or part of the technical solution that contributes to the prior art or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, RandomAccess Memory), disk or optical disk and other media that can store program code.

[0189] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. An event-driven high-speed road ramp control method, characterized in that: The method comprises: Acquire historical vehicle data, wherein the historical vehicle data includes speed average, density average and flow sum; Determine a first speed, a second speed and a congestion density corresponding to a preset time period according to the historical vehicle data, and determine at least one light control period within the preset time period according to the first speed and the speed average, wherein the first speed is the critical vehicle speed average for starting congestion, and the second speed is the critical vehicle speed when there is a vehicle that cannot move forward on the ramp; If the current time period belongs to the light control time period, the current speed, current density and current queue length corresponding to the current time period are obtained, and a first green-to-signal ratio of the current time period is determined according to the current density and the blocking density, and a second green-to-signal ratio of the current time period is determined according to the current queue length; The current speed and the first speed and the second speed are compared to obtain a first comparison result, and the current queue length is compared with a preset queue threshold to obtain a second comparison result, and a target green-to-signal ratio is determined based on the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio and the preset maximum green-to-signal ratio, and high-speed road ramp traffic control is performed based on the target green-to-signal ratio.

2. The event-driven high-speed road ramp control method according to claim 1, characterized in that: The determining of the first speed, the second speed and the blocking density corresponding to the preset time period according to the historical vehicle data, and determining at least one light control period within the preset time period according to the first speed and the speed mean, comprises: Determine the maximum flow and the blocking density according to the historical vehicle data, use the speed value corresponding to the maximum flow as the first speed, and use the speed value corresponding to the blocking density as the second speed; The time period in which the average speed in the preset time period is less than or equal to the first speed is used as the candidate time period; Determine whether the duration of each of the selected time periods is greater than a preset duration; If yes, then determine in sequence whether the time intervals of adjacent selected time periods are less than the preset time length; If yes, the adjacent time periods to be selected and the corresponding time intervals are combined into one light control time period; if no, the adjacent time periods to be selected are each taken as one light control time period.

3. The event-driven high-speed road ramp control method according to claim 2, characterized in that: The determining the maximum flow rate and the blocking density according to the historical vehicle data comprises: Input the velocity mean and density mean into the velocity-density relationship to calculate the blocking density; The total flow rate and the mean density are input into the flow-density relationship to calculate the maximum flow rate.

4. The event-driven high-speed road ramp control method according to claim 1, characterized in that: Determining a first green-to-signal ratio of a current period according to the current density and the blocking density includes: Determine current occupancy based on current density; Calculating a difference between a preset critical occupancy rate and the current occupancy rate, and taking a product of the difference and a preset calibration parameter as a first intermediate value; The sum of the first green-to-signal ratio of the previous period of the current period and the first intermediate value is used as the first green-to-signal ratio of the current period.

5. The event-driven high-speed road ramp control method according to claim 1, characterized in that: Determining a second green-to-signal ratio of a current time period according to the current queue length includes: Calculate the quotient of the current queue length and the queue threshold, and take the difference between the quotient and 1 as the second intermediate value; The product of the second intermediate value and the preset ramp queue adjustment rate is used as the third intermediate value; The sum of the second green-to-signal ratio of the previous period of the current period and the third intermediate value is used as the second green-to-signal ratio of the current period.

6. The event-driven high-speed road ramp control method according to claim 1, characterized in that: The determining a target green-to-signal ratio according to the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio, and a preset maximum green-to-signal ratio includes: If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is less than or equal to the queue threshold, determining a first minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio, and using the first minimum value as the target green-to-signal ratio; If the first comparison result indicates that the current speed is less than the first speed and greater than the second speed, and the second comparison result indicates that the current queue length is greater than the queue threshold, determining a maximum value between the first green-to-signal ratio and the second green-to-signal ratio, and determining a second minimum value between the maximum value and the maximum green-to-signal ratio, and using the second minimum value as the target green-to-signal ratio; If the first comparison result indicates that the current speed is not greater than the second speed, a third minimum value between the first green-to-signal ratio and the maximum green-to-signal ratio is determined, and the third minimum value is used as a target green-to-signal ratio.

7. The event-driven high-speed road ramp control method according to claim 1, characterized in that: The high-speed road ramp traffic control according to the target green-to-signal ratio includes: Comparing the green-to-signal ratios in each pre-established ramp control scheme according to the target green-to-signal ratio, taking the ramp control scheme corresponding to the green-to-signal ratio with the smallest difference between the target green-to-signal ratio and the green-to-signal ratio as the target ramp control scheme, wherein the ramp control scheme includes the green-to-signal ratio and the ramp light control strategy; Carry out traffic control on the expressway ramp according to the ramp light control strategy in the target ramp control plan.

8. An event-driven high-speed road ramp control device, characterized in that: The device comprises: An acquisition module, used to acquire historical vehicle data, wherein the historical vehicle data includes a speed average, a density average, and a flow sum; A first determination module is used to determine a first speed, a second speed and a congestion density corresponding to a preset time period according to the historical vehicle data, and to determine at least one light control period within the preset time period according to the first speed and the speed average, wherein the first speed is the critical vehicle speed average for starting congestion, and the second speed is the critical vehicle speed when there is a vehicle that cannot move forward on the ramp; a second determination module, configured to obtain a current speed, a current density, and a current queue length corresponding to the current time period if the current time period belongs to a light-controlled time period, and determine a first green-to-signal ratio of the current time period according to the current density and the blocking density, and determine a second green-to-signal ratio of the current time period according to the current queue length; A control module is used to compare the current speed with the first speed and the second speed to obtain a first comparison result, and compare the current queue length with a preset queue threshold to obtain a second comparison result, determine a target green-to-signal ratio based on the first comparison result, the second comparison result, the first green-to-signal ratio, the second green-to-signal ratio and a preset maximum green-to-signal ratio, and perform high-speed road ramp traffic control based on the target green-to-signal ratio.

9. An electronic device, characterized in that: include: A processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor executes the machine-readable instructions to perform the steps of the event-driven high-speed road ramp control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the event-driven high-speed road ramp control method as claimed in any one of claims 1 to 7 are executed.

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