Highway small-radius ramp vehicle-road cooperative driving warning and merging method

Abstract

The present application relates to the technical field of intelligent driving, and discloses a highway small-radius ramp vehicle-road cooperative driving early warning and merging method, comprising the following steps: step 1: information acquisition hardware facilities are arranged at the ramp and the main road, identity information, weather information and ramp data of vehicles are acquired, and the movement and position information of vehicles on the main road and the ramp are collected in real time; step 2: a dynamic speed limit reminding device is arranged on the ramp, the dynamic safe driving speed of the current ramp is calculated according to the ramp data and the weather information, and speed early warning is issued on the dynamic speed limit reminding device; step 3: ramp vehicle merging information is predicted, and networked vehicles are segmented and cooperatively grouped in real time, and the ramp vehicles in each group intelligently and cooperatively merge into the main road of the highway; if the vehicle is not networked, the driving track of the vehicle is predicted according to the movement and position information of the vehicle on the ramp. A method for early warning of driving at a small-radius ramp is provided.

Description

Technical Field

[0001] This invention relates to the field of intelligent driving technology, specifically to a method for early warning and merging of vehicle-road cooperative driving on small-radius ramps of highways. Background Technology

[0002] Due to limitations imposed by economic, aesthetic, environmental, and social factors, the curve radius of ramps must be controlled within a small range during construction. This makes them highly susceptible to traffic accidents after they are put into operation, which has an adverse impact on safe operation.

[0003] With the rapid development of the Internet of Things (IoT) and connected vehicles, applying vehicle-road cooperative technology to small-radius ramps has significant advantages. These advantages lie in its ability to assist drivers in making better decisions and judgments, thereby improving driving safety. Furthermore, compared to traditional vehicles, intelligent connected vehicles offer the following advantages: higher safety, as they are equipped with advanced safety systems that effectively reduce traffic accidents; enhanced information exchange and data sharing capabilities, enabling interconnection between vehicles and people, and between vehicles themselves; and real-time traffic information acquisition and processing. Finally, this technology also demonstrates excellent performance and effectiveness on light-duty grade-separated highways.

[0004] If the design speed of the interchange mainline is 100-120 km / h, and the ramp radius uses the extreme radius, vehicles entering the ramp's basic section will have a relatively high speed. If drivers fail to slow down in time before entering the small-radius ramp, or if they make a driving error, they may exit the interchange mainline at a high speed. If drivers cannot accurately judge the appropriate speed for the small-radius ramp and fail to slow down in time, the superelevation will not provide the centrifugal force needed for separation, leading to traffic accidents. Furthermore, vehicles (especially large vehicles) with a high center of gravity are highly susceptible to serious accidents such as overturning off the ramp. Because small-radius ramps present safety hazards such as excessive turning speeds, high driving difficulty, and poor visibility, the accident rate at small-radius ramps on highways remains high, posing a significant threat to life and property. Therefore, excessive speed at small-radius ramps is a major cause of traffic accidents, making enhanced speed warnings at these locations crucial. Summary of the Invention

[0005] The present invention aims to provide a method for vehicle-road cooperative driving warning and merging at small-radius ramps on highways, so as to provide a method for providing warning of traffic at small-radius ramps.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for early warning and merging of vehicle-road cooperative driving on small-radius ramps of highways, comprising the following steps:

[0007] Step 1: Set up information collection hardware facilities at ramps and main roads to obtain vehicle identity information, weather information and ramp data, and collect real-time information on vehicle movement and location on the main road and ramps.

[0008] Step 2: Install dynamic speed limit reminder devices on the ramps, calculate the current dynamic safe driving speed of the ramps based on ramp data and weather information, and issue speed warnings on the dynamic speed limit reminder devices;

[0009] Step 3: Predict the merging information of vehicles on the ramp, including determining whether the vehicles on the ramp are connected vehicles. If they are connected vehicles, the connected vehicles are grouped in real time and each group of ramp vehicles intelligently and collaboratively merges into the main road of the highway. If they are not connected vehicles, the vehicle's trajectory is predicted based on the vehicle's movement and location information on the ramp. Vehicle detection warning signs are set up at the point where ramp vehicles merge into the main road to issue warnings to vehicles on the main road.

[0010] The beneficial effects of this plan are:

[0011] This invention enables real-time processing of high-precision radar monitoring data and high-precision positioning data in ramp areas through multi-source access to ramp area data. This reduces information flow time, increases the timeliness of events, and, in conjunction with dynamic alerts for main roads and ramps, provides early warnings to assist drivers in assessing road conditions, thereby effectively preventing accidents.

[0012] By calculating the ramp area, the behavior trajectory prediction of multiple vehicles in the ramp area can be realized; by predicting the position of vehicles in the ramp area, lane-level early warning information can be realized, providing strategic and lane-level control service support for ramp lane change accident early warning, traffic violation information reminder, traffic condition prediction, etc., thereby improving the safety level of the ramp area and reducing the accident rate of the ramp area.

[0013] Preferably, as an improvement: in step 3, the cooperative grouping of connected vehicles specifically includes the following steps:

[0014] Step 3.1: From the entrance end of the ramp to the exit end, there are sequentially a control section, a grouping section, a grouping completion section, and a merging section. When a vehicle on the ramp arrives at the first section of the control section, the vehicle's identity information is identified to determine whether the vehicle is an intelligent connected vehicle. If the vehicle is an intelligent connected vehicle, the intelligent connected vehicles on the ramp are coordinated and controlled.

[0015] Step 3.2: Ramp vehicles are grouped in the grouping section, so that all intelligent connected vehicles from the control area to the grouping section form a group. If a non-connected vehicle appears in the middle, the grouping will end automatically. The location range of the mainline cooperative vehicle is calculated, and the connected vehicles on the mainline cooperative vehicle are coordinated and controlled. A gap is reserved on the main road for the grouped vehicles on the ramp to merge.

[0016] Step 3.3: Calculate the merging time available on the main road and coordinate the control of the train group to accelerate into the main road.

[0017] The beneficial effects are as follows: Real-time coordinated grouping of vehicles on ramps and intelligent merging them into the main highway. This improves the driving efficiency of ramp vehicles and the overall traffic flow; information processing hardware predicts vehicle trajectories. This helps to more accurately understand vehicle dynamics and make corresponding decisions and warnings. Through intelligent grouping of ramp vehicles via the Internet of Things, while ensuring safe and smooth traffic flow on the main line, information prompts facilitate lane exchanges between connected and non-connected vehicles on the main line, providing space for ramp vehicles to merge.

[0018] By optimizing train formation, providing merging gaps, and controlling merging speed, this method can improve the merging efficiency and safety of ramp vehicles. Ramp vehicles can accelerate and merge into the main road more smoothly, reducing dangerous behaviors such as emergency braking and rapid acceleration during the merging process, thereby reducing the probability of accidents.

[0019] Preferably, as an improvement, if the vehicle speed exceeds the dynamic safe driving speed threshold during driving, the in-vehicle navigation system will issue an overspeed warning.

[0020] The beneficial effect is that if the vehicle speed exceeds the dynamic safe driving speed threshold, the in-vehicle navigation system will issue an overspeed warning, thereby reducing the frequency of traffic accidents at ramps.

[0021] Preferably, as an improvement, the dynamic safe driving speed threshold is calculated using the following formula:

[0022]

[0023] The beneficial effects are as follows: This dynamic safe driving speed threshold comprehensively considers factors such as ramp speed limit, comfort acceleration, ramp width, number of lanes, ramp radius, and adverse weather correction coefficient to calculate the maximum safe speed threshold of the ramp. By performing real-time calculation and analysis for the specific conditions of different ramps, the reliability of this speed threshold is ensured, while meeting the comfort and safety needs of drivers.

[0024] Preferably, as an improvement, the value of β is as follows: β is 0.83 for rainy days, β is 0.72 for snowy days, and β is 0.85 for foggy days.

[0025] The beneficial effects are as follows: Under different weather conditions, such as rain, snow and fog, the slipperiness of the road and visibility will be affected. By using different correction coefficients β, the maximum safe speed threshold can be adjusted according to the specific weather conditions to adapt to the current road conditions, avoid potential dangers caused by the weather, and improve driving safety.

[0026] Preferably, as an improvement, the ramp data includes current ramp accident data, ramp curvature, slope, traffic flow, and speed limit; the accident data includes accident location, accident type, and accident severity; and the affected road sections and scope are marked on the vehicle-mounted high-precision map.

[0027] The beneficial effect is that by utilizing accident data and ramp data, drivers can be provided with more accurate real-time risk warnings. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall method for vehicle-road cooperative grouping and merging of small-radius ramps according to the present invention;

[0029] Figure 2 This is a schematic diagram of the vehicle detection and warning sign of the present invention;

[0030] Figure 3 This is a schematic diagram of the dynamic speed limit reminder device of the present invention. Detailed Implementation

[0031] The following detailed description illustrates the specific implementation method:

[0032] The reference numerals in the accompanying drawings include: 1. High-precision radar; 2. Vehicle detection and warning sign; 3. Dynamic speed limit reminder device; 4. Connected vehicle; 5. Non-connected vehicle; 6. Trained vehicle; 7. Mainline cooperative vehicle; 8. Display screen; 9. Variable LED speed dynamic prompt screen; 10. Overspeed warning screen.

[0033] Example

[0034] The implementation examples are basically as follows Figures 1-3 As shown, Figure 1 The method for vehicle-road cooperative driving warning and merging on small-radius ramps of highways, as shown, includes the following steps:

[0035] Step 1: Install information collection hardware facilities at ramps and main roads, such as... Figure 1As shown, a high-precision radar 1 is installed at the starting point M of the ramp and at the beginning point N of the acceleration lane. The high-precision radar 1 is installed at a spacing of 100-200m within the ramp section. A high-definition camera is installed every 80-120m along the ramp section. A high-precision radar 1 is installed every 250-350m along the side of the main road of the highway. The information collection hardware facilities acquire vehicle identity information, weather information, and ramp data, and collect real-time data on vehicle movement and location information on the main road and ramps.

[0036] Ramp data includes current ramp accident data, ramp curvature, slope, traffic flow, and speed limit. Accident data includes accident location, accident type, and accident severity. Combining accident type, data reception status, and vehicle operation status, the system can determine the scope of the accident's impact in real time, down to the lane and radius of influence. The affected road sections and the scope involved are marked on the vehicle-mounted high-precision map to remind vehicles to pay attention to driving safety.

[0037] Step 2: Install dynamic speed limit reminder devices 3 on the ramps, such as... Figure 3 As shown, the dynamic speed limit reminder device 3 is equipped with a variable LED speed dynamic prompt screen 9 and an overspeed warning screen 10. On the ramp section, from point M to point N, a dynamic speed limit reminder device 3 is installed every 100-200m. The dynamic safe driving speed of the current ramp is calculated based on ramp data and weather information, and a speed warning is issued on the dynamic speed limit reminder device 3.

[0038] The dynamic safe driving speed threshold is calculated using the following formula:

[0039]

[0040] In the formula: V max V0 is the maximum safe speed threshold for the ramp, in km / h; V0 is the speed limit displayed on the ramp speed limit sign, in km / h; a best To ensure driver comfort, an acceleration value of 2 m / s² is chosen. 2 ; d is the ramp width, m; n is the number of ramp lanes; R is the ramp radius, m; β is the adverse weather impact correction factor.

[0041] The following table shows the correction factors for the impact of adverse weather on maximum vehicle speed:

[0042] Table 1 Correction Factors for the Impact of Adverse Weather

[0043]

[0044] If the vehicle speed exceeds the dynamic safe driving speed threshold during driving, the in-vehicle navigation system will issue an overspeed warning.

[0045] Step 3: Predict the merging information of vehicles on the ramp, including determining whether the vehicles on the ramp are connected vehicles 4. If they are connected vehicles 4, they are grouped into segments for real-time collaborative merging. Each group of vehicles on the ramp intelligently and collaboratively merges into the main road of the highway. If they are non-connected vehicles 5, the vehicle's trajectory is predicted based on the vehicle's movement and location information on the ramp. Vehicle detection warning signs 2 are set up at the point where the ramp vehicles merge into the main road to issue warnings to vehicles on the main road. Warning signs are set up on both sides of the main road.

[0046] Step 3.1: From the entrance end of the ramp to the exit end, there are sequentially a control section, a grouping section, a grouping completion section, and a merging section. When a vehicle on the ramp arrives at point A at the beginning of the control section, the vehicle's identity information is identified to determine whether the vehicle is an intelligent connected vehicle. If the vehicle is an intelligent connected vehicle, it is grouped into a group.

[0047] Step 3.2: After being grouped in the grouping section, connected vehicle 4 becomes grouped vehicle 6. The starting point of the grouping section is 250-300m away from the beginning of the acceleration lane along the ramp direction. The length of the grouping section is 50m. All intelligent connected vehicles 4 from point A at the beginning of the ramp control area to the grouping section form a group. If a non-connected vehicle 5 appears in the middle, the grouping will end automatically. When connected vehicle 4 reaches point C at the end of the grouping section, the grouping is completed, and the grouped vehicle 6 is coordinated and controlled.

[0048] The location range of the mainline cooperative vehicle 7 is calculated, and the location range of the mainline cooperative vehicle 7 is determined according to the following formula:

[0049]

[0050] In the formula: l i The distance traveled from point A to the end of the acceleration lane is the actual distance traveled, in meters (m). L1 is the average speed of vehicles on the main road, in m / s; L1 is the distance of the cooperating vehicle from the right end of the expected merging interval, in m; v max This is the maximum speed limit within the ramp, in m / s.

[0051] After adjusting their speed and spacing, the convoy of vehicles 6 on the ramp reaches the merging completion section. The starting point F of the merging completion section coincides with the starting point of the acceleration lane, and the straight-line length of the merging completion section is 30 meters. At this point, the speed of connected vehicles within the range of the mainline cooperating vehicle 7 is adjusted. Vehicles on the mainline reserve merging gaps for the convoy of vehicles 6 on the ramp, ensuring that the convoy arrives at the merging section empty of any other vehicles. Simultaneously, non-connected vehicles in this area will be reminded by signs to drive in the two leftmost lanes, providing a good merging environment for ramp vehicles.

[0052] For non-intelligent connected vehicles and intelligent connected vehicles that cannot be grouped, the speed limit displayed on the ramp speed limit sign is used as a basis. At the same time, high-precision radar 1 and high-definition camera transmit traffic flow information to the vehicle speed controller. Based on the above information, the maximum safe speed threshold of the current vehicle is calculated through the dynamic safe driving speed threshold. The current vehicle must travel at a speed lower than this speed. If the vehicle speed exceeds the above threshold during driving, the on-board navigation system and intelligent speed limit sign will issue an overspeed warning.

[0053] Step 3.3: Calculate the merging time available on the main road and coordinate the acceleration of train 6 to merge onto the main road.

[0054] The available inbound time G of the mainline is calculated according to the following formula:

[0055]

[0056] In the formula: C max Q represents the maximum capacity of the rightmost lane on the main line, expressed as pcu / h; Q represents the traffic volume of each lane on the main line, expressed as pcu / h. Let be the average headway, in seconds.

[0057] like Figure 2 As shown, the vehicle detection and warning sign 2 assists vehicles merging into the main road from the ramp. When the vehicle detection and warning sign 2 receives information about a convoy merging into the main road, the display screen 8 on the vehicle detection and warning sign 2 will display a "Caution and Avoidance" sign, thereby improving the safety of vehicle merging.

[0058] Taking a small-radius ramp of a certain expressway as an example,

[0059] 1) The basic data of a small-radius ramp of a certain expressway are shown in Table 1 after investigation.

[0060] Table 1 Basic data of a small-radius ramp on a certain expressway

[0061] <![CDATA[l i ]]> <![CDATA[v0]]> d n R 800m 40km / h 7m 2 70m

[0062] 2) The data collection and calculation module collects weather conditions and real-time road conditions. Taking a ramp in rainy weather as an example, the following data was collected.

[0063] Table 2 Data collected on a certain highway

[0064]

[0065] 3) Based on the formula, substituting the relevant data into the calculation yields the location interval of the mainline cooperating vehicle 7 and the merging time gap T that the mainline vehicle can provide. G :

[0066] 1600m≤L1≤1700m

[0067] T G =6.3s

[0068] 4) Based on the formula, substituting the relevant data into the calculation, the maximum safe speed threshold for small-radius ramps under the intelligent speed limit method for ramps in rainy conditions can be obtained:

[0069] V max =28.47km / h

[0070] This invention also aims to provide a system for early warning and merging of vehicle-road cooperative driving on small-radius ramps on highways, applicable to the aforementioned method for early warning and merging of vehicle-road cooperative driving on small-radius ramps on highways, including:

[0071] The data acquisition module includes a high-precision radar 1, a high-precision GPS, a camera, and a high-precision detector installed on ramps and main roads;

[0072] The data processing module performs boundary processing of the ramps, extracts and calculates data at the data level, feature level, and decision level, and predicts the vehicle's driving trajectory.

[0073] The calculation module calculates the location range of the mainline cooperating vehicle 7, and calculates the merging length and maximum safe speed threshold that the mainline can provide.

[0074] The early warning information release module includes vehicle detection and early warning signs set on the main road and dynamic speed limit reminder devices set on the ramps.

[0075] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for early warning and merging of vehicle-road cooperative driving on small-radius ramps of expressways, characterized by: Step 1: Install information collection hardware facilities at the ramps and main roads, including installing a high-precision radar at the starting point M of the ramp and at the beginning point N of the acceleration lane, with high-precision radars spaced every 100-200m along the ramp section; install a high-definition camera every 80-120m along the ramp section; and install a high-precision radar every 250-350m along the side of the highway main road. These hardware facilities will acquire vehicle identification information, weather information, and ramp data, and will collect real-time data on vehicle movement and location on the main road and ramps. Ramp data includes current ramp accident data, ramp curvature, slope, traffic flow, and speed limit. Accident data includes accident location, accident type, and accident severity. On the vehicle-mounted high-precision map, the affected road sections and the scope of the accident are marked. Step 2: Install dynamic speed limit reminder devices on the ramps. Each dynamic speed limit reminder device is equipped with a variable LED speed dynamic display screen and an overspeed warning screen. On the ramp section, from point M to point N, install a dynamic speed limit reminder device every 100-200m. Calculate the current dynamic safe driving speed of the ramp based on ramp data and weather information, and issue a speed warning on the dynamic speed limit reminder device. The dynamic safe driving speed threshold is calculated using the following formula: In the formula: The maximum safe speed threshold for the ramp is [value] km / h. The speed limit displayed on the ramp speed limit sign is in km / h. To ensure driver comfort, the acceleration value is set to [value to be filled in]. d is the ramp width, in meters; n is the number of ramp lanes; R is the ramp radius, in meters. This is a correction factor for the impact of adverse weather conditions. Step 3: Predict the merging information of vehicles on the ramp, including determining whether the vehicles on the ramp are connected vehicles. If they are connected vehicles, the connected vehicles are divided into segments and coordinated in real time. Each group of vehicles on the ramp intelligently and coordinatedly merges into the main road of the highway. If they are not connected vehicles, the vehicle's trajectory is predicted based on the vehicle's movement and location information on the ramp. Vehicle detection and warning signs are installed at the points where vehicles merge from ramps onto the main road to warn vehicles on the main road of ramp merging.

2. The method for early warning and merging of vehicle-road cooperative driving on highway small-radius ramps according to claim 1, characterized in that: Step 3 specifically includes the following steps for the collaborative grouping of connected vehicles: Step 3.1: From the entrance end of the ramp to the exit end, there are sequentially a control section, a grouping section, a grouping completion section, and a merging section. When a vehicle on the ramp arrives at the first section of the control section, the vehicle's identity information is identified to determine whether the vehicle is an intelligent connected vehicle. If the vehicle is an intelligent connected vehicle, the intelligent connected vehicles on the ramp are coordinated and controlled. Step 3.2: Ramp vehicles are grouped in the grouping section, so that all intelligent connected vehicles from the control area to the grouping section form a group. If a non-connected vehicle appears in the middle, the grouping will end automatically. The location range of the mainline cooperative vehicle is calculated, and the connected vehicles on the mainline cooperative vehicle are coordinated and controlled. A gap is reserved on the main road for the grouped vehicles on the ramp to merge. Step 3.3: Calculate the merging time available on the main road and coordinate the control of the train group to accelerate into the main road.

3. The method for early warning and merging of vehicle-road cooperative driving on small-radius ramps of expressways according to claim 2, characterized in that: If the vehicle speed exceeds the dynamic safe driving speed threshold during driving, the in-vehicle navigation system will issue an overspeed warning.

4. The method for early warning and merging of vehicle-road cooperative driving on small-radius ramps of expressways according to claim 3, characterized in that: The values ​​of β are as follows: 0.83 for rainy days, 0.72 for snowy days, and 0.85 for foggy days.

Images