CN103000035A - Information acquisition release system and method for guiding left-hand turning vehicle to pass through intersection - Google Patents

Abstract

The present invention provides a system and method for information acquisition and release for guiding left-turning vehicles through intersections. The system includes: a central controller, a first sensor, a second sensor and a display device: the central controller communicates with the first sensor, the second sensor, and the display device respectively. The second sensor is connected to the display sign, and is used to process traffic vehicle information; the first sensor is located at the design speed V distance of the road where the absolutely safe vehicle gap T* of the opposite straight lane stops, and is used to obtain the straight line entering the intersection The entry time point and driving speed of the vehicle; the second sensor is located at the stop line of the oncoming straight lane, and is used to detect the out-going straight vehicle; and the display device is used to display vehicle information on the oncoming straight lane. The system and method provide advice information for left-turning vehicles whether to turn left, help left-turning drivers judge the vehicle clearance of straight-going vehicles, increase the traffic capacity of intersections, and reduce dangerous conflicts between left-turning vehicles and straight-going vehicles.

Description

Information Acquisition and Release System and Method for Guiding Left-turning Vehicles to Pass Intersections

technical field

The invention relates to the technical field of traffic information acquisition and processing, in particular to an information acquisition and release system and method for guiding left-turn vehicles to pass through intersections in highway traffic.

Background technique

In the signal control method of the existing signalized intersection, when there are no more than 4 left-turning standard vehicles in a certain direction within a signal cycle, the left-turning vehicles in this direction do not set up a left-turning special phase separately, and the left-turning vehicles It shares a phase with the oncoming straight vehicle, and the left-turning vehicle needs to pass through the vehicle gap of the oncoming straight vehicle. Whether the left-turning driver passes depends entirely on the judgment of the vehicle gap, and the accuracy of the judgment directly affects traffic safety. , according to the road traffic regulations in the United States, when the time distance between straight-going vehicles reaches more than 5.5s, it is safe, which is called the intervehicle gap. When the left-turn driver underestimates the real time headway, he will choose to continue waiting The opportunity to pass through is wasted, and the efficiency of intersection traffic is reduced; when the left-turning driver overestimates the real headway, the driver may try to pass through, but the real vehicle gap cannot meet the vehicle passing through, so straight-going vehicles and left-turning are very likely to occur Vehicles collide, and because the direction of travel of the left-turning vehicle and the straight-going vehicle may be perpendicular, the probability of a side collision is greater, and the accident severity of the side collision accident is high and the injury is large. Especially in the case of poor sight distance at intersections, it is more likely to cause incorrect judgments. For example, mountainous areas, foggy days, and snowy days will all cause poor sight distances. Previous studies have found that about 30% of left-turn accidents are caused by misjudgment of the gaps that can be inserted into vehicles (Chovan et al., 1994), and Staplin (1995) and Yan Xuedong (2007) have found that the elderly have poor eyesight, Responses are slower and errors of judgment are more likely to occur. In addition, in the left-turn accidents, the accidents with poor sight distance as the main cause accounted for 24.4%. The poor sight distance may also be caused by the opposite left-turning vehicle. Drivers watch for oncoming through traffic, especially at intersections where the center vacancy is too large (Yan and Radwan, 2004 and 2007). The frequent occurrence of left-turn accidents and the high severity of accidents not only restrict the traffic capacity of intersections, but also pose a huge challenge to traffic safety, endangering the safety of drivers' lives and properties. Therefore, how to help left-turning vehicles to judge the gaps that can be inserted into vehicles and provide necessary information prompts for left-turning vehicles has become a major problem.

Contents of the invention

(1) Technical problems to be solved

The invention provides an information acquisition and release system and method for guiding a left-turning vehicle to pass an intersection, which helps the left-turning vehicle to judge the gap that can be inserted, and provides necessary information prompts for the left-turning vehicle.

(2) Technical solution

The present invention provides an information acquiring and distributing system for guiding left-turning vehicles through an intersection, the system comprising: a central controller, a first sensor, a second sensor and a display device:

The central controller is respectively connected with the first sensor, the second sensor and the display device, and is used to process the traffic vehicle information and control the work of each component of the system;

The first sensor is located at a distance of T*V from the stop line of the opposite through lane, and is used to obtain the entry time point and driving speed of the through vehicle entering the intersection; where T is an absolutely safe vehicle gap, and the T is greater than the Gap; V is the design speed of the road to which it belongs;

The second sensor is located at the stop line of the opposite through lane, and is used to detect the out of the through vehicle;

The display device is used to display vehicle information in the oncoming straight lane.

Preferably, the system further includes a third sensor, which is connected to the central controller and located at a preset distance from the stop line of the left-turn lane for detecting whether there is a left-turn vehicle.

Preferably, the third sensor is an induction coil.

Preferably, the first sensor is a double induction coil, the second sensor is an induction coil, and the display device is a variable information traffic sign.

Preferably, the vehicle information displayed on the variable information traffic sign includes: text prompt information on the top, color-changing vehicles in the middle, and vehicle speeds on the bottom.

Preferably, the color-changing vehicle displays red flashes, indicating that left-turning vehicles are prohibited from passing, and the vehicle displays yellow flashing, indicating that left-turning vehicles are advised to pass carefully.

Preferably, said T=5.5+1.96*σ, where σ is the standard deviation of a normal distribution.

Preferably, the value range of σ is [1, 2].

The present invention also provides a method for obtaining and distributing information for guiding left-turning vehicles through an intersection, the method comprising:

S1. The first sensor obtains the entry time point and driving speed of the straight vehicle entering the intersection, and sends the information to the controller;

S2. The central controller assigns numbers to the through vehicles entering the intersection in sequence, and controls the display device to display the speed of the vehicle represented by the first number; at the same time, subtract the entry time points of the through vehicles with adjacent numbers to obtain the vehicle time interval, and Judging whether the vehicle time interval between the first numbered vehicle and the second numbered vehicle is less than the absolutely safe vehicle gap, if so, then control the display device to display the traffic prohibition information of left-turn vehicles, otherwise, control the display device to display the traffic information of suggested left-turn vehicles;

S3. The second sensor detects the vehicle leaving the straight lane, and the central controller resets the number of the passing vehicle to zero, no longer participates in information detection, and controls the display device to release the vehicle information of the next number.

Preferably, before the step S1, the third sensor detects whether there is a left-turning vehicle. If there is no left-turning vehicle, the central controller controls the display screen of the display device to be turned off. If there is a left-turning vehicle, the central controller controls the Shows the steps in which the device display is activated.

(3) Beneficial effects

The present invention adopts a brand-new system and method for obtaining and distributing information by using the variable information traffic sign VMS to guide left-turning vehicles to safely pass through the intersection at the intersection with poor sight distance. , calculate the vehicle gap between adjacent vehicles, and provide a VMS release method to release vehicle speed and vehicle gap information, assist left-turn drivers to make stop-and-go judgments, and reduce violent conflicts between straight-going vehicles and left-turning vehicles , avoiding the occurrence of traffic accidents is of great significance to intersection safety and intersection traffic efficiency.

Description of drawings

Fig. 1 is the composition schematic diagram of the system provided by the present invention;

Fig. 2 is a schematic diagram of the system provided by the present invention in actual road application;

Fig. 3 is a flowchart of the steps of the method provided by the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

The present invention provides an information acquisition and distribution system for guiding left-turning vehicles to pass through an intersection. As shown in Figure 1, the system includes: a central controller, a first sensor, a second sensor and a display device:

The central controller is respectively connected with the first sensor, the second sensor and the display device, and is used to process the traffic vehicle information and control the work of each component of the system;

The first sensor is at a distance S from the stop line of the through lane at the intersection, and is used to obtain the entry time point and driving speed of the through vehicle entering the intersection. The distance S is determined by the absolute safety time T and the design speed V of the road to which it belongs: S=T*V . Since the time distance between straight vehicles is more than 5.5s, it is safe. Considering the driver's reaction time and the difference in operating proficiency, the absolutely safe vehicle gap T must be greater than 5.5s.

The second sensor is located at the stop line of the opposite straight lane, and is used to detect vehicles driving out of the straight lane;

The display device is used to display vehicle information in the oncoming straight lane.

The system also includes a third sensor, which is connected with the central controller and located at a preset distance from the stop line of the left-turn lane, and is used to detect whether there is a left-turn vehicle.

Fig. 2 is a schematic diagram of the system in an actual road. Here the third sensor is an induction coil 1, the first sensor is a double induction coil 2, the second sensor is an induction coil 3, and the display device is a variable information traffic sign;

The induction coil 1 is located 5m away from the stop line of the left-turning vehicle, and the double induction coil 2 is at a distance S from the through lane of the intersection. The distance S is determined by the absolute safety time T and the design speed V of the road to which it belongs: S=T*V. Since the time distance between straight vehicles is more than 5.5s, it is safe. Considering the driver's reaction time and the difference in operating proficiency, the absolutely safe vehicle gap T must be greater than 5.5s.

It is assumed here that the time that vehicles can pass through the intersection obeys the normal distribution of (5.5, σ ² ), and the time when 95% of the vehicle drivers can pass through the intersection is taken as the absolute safety vehicle clearance in the present invention, then the absolute safety vehicle clearance T= 5.5+1.96*σ, σ is the standard deviation of the normal distribution, σ is directly related to the driver's attention and operating skills, and the recommended value range is [1, 2]. For example, the absolute safety vehicle gap is 10s, and the speed limit of the main road in the city is generally 60km/h. To detect the absolute safety state of the left-turning vehicle, the distance between the coil 2 and the stop line needs to reach (10*60/3.6)= 166.666m is taken as 170m, therefore, a set of double induction coils 2 is installed 170m upstream of the intersection where the opposite through traffic flow enters. At the same time, this distance also ensures the visual distance of the intersection.

An induction coil 3 is placed at the stop line of the straight lane to detect the straight vehicles that roll out.

The variable information traffic sign VMS, the background color is black, and the VMS sign is composed of three parts, as shown in the VMS in Figure 1: the text prompt information at the top, the variable color vehicle in the middle, and the vehicle speed at the bottom. The text prompt information is "Please pay attention to the car coming ahead", reminding the left-turn driver to pay attention to the straight-going vehicle. The text color is red, which has a greater warning effect on the driver. Since it is a VMS sign, the text part can be adjusted according to the specific road and traffic. The situation changes; the color-changing vehicle has two states of red flashing and yellow flashing, red flashing means that vehicles turning left are forbidden to pass, yellow flashing means that vehicles turning left are advised to pass carefully; vehicle speed always shows the speed of the first car behind the stop line (unit is kilometers per hour), directly displayed in the form of numbers, to assist the left-turn driver to judge.

As shown in Figure 3, it is the method for obtaining and distributing information for guiding a left-turning vehicle to pass through an intersection according to the present invention, the method comprising:

S1. The first sensor obtains the entry time point and driving speed of the straight vehicle entering the intersection, and sends the information to the controller;

S2. The central controller assigns numbers to the through vehicles entering the intersection in sequence, and controls the display device to display the speed of the vehicle represented by the first number; at the same time, subtract the entry time points of the through vehicles with adjacent numbers to obtain the vehicle time interval, and Judging whether the vehicle time interval between the first numbered vehicle and the second numbered vehicle is less than the absolutely safe vehicle gap, if so, the color-changing vehicle logo in the control display device is in a red flashing state, indicating that left-turn vehicles are prohibited from passing, otherwise, the control display device can The color-changing vehicle logo is flashing yellow, indicating that vehicles turning left are advised to pass;

S3. The second sensor detects the vehicle leaving the straight lane, and the central controller resets the number of the passing vehicle to zero, no longer participates in information detection, and controls the display device to release the vehicle information of the next number.

Based on the actual road system shown in Figure 2, the information acquisition and release method for guiding left-turning vehicles through intersections:

S1. The induction coil 1 detects whether there is a left-turning vehicle. If there is no left-turning vehicle, the central controller controls the display sign display to be turned off. If there is a left-turning vehicle, the central controller controls the display sign display to be activated;

S2. The double induction coil 2 acquires the entry time point and driving speed of the straight vehicle entering the intersection, and sends the information to the controller;

S3. The central controller assigns numbers to the through vehicles entering the intersection in sequence, and controls the display device to display the speed of the vehicle represented by the first number; at the same time, subtract the entry time points of the through vehicles with adjacent numbers to obtain the vehicle time interval, and Determine whether the vehicle time interval between the first numbered vehicle and the second numbered vehicle is less than the absolute safety vehicle gap, if so, control the variable information traffic sign to display the information that the left-turning vehicle is prohibited; otherwise, control the variable informational traffic sign to display the suggested left-turning vehicle traffic information;

S4. The sensor coil 3 detects the vehicle leaving the straight lane, and the central controller resets the number of the passing vehicle to zero, no longer participates in information detection, and controls the variable information traffic sign to issue the next numbered vehicle information.

After the system starts running, when the first straight-driving vehicle passes the double induction coil 2, the induction coil will detect the vehicle information, including the speed of the vehicle and the passing time, and send the information to the central controller, which will give the vehicle Number 1, each subsequent vehicle also detects the same vehicle information, and numbers them sequentially to form a vehicle number sequence 1, 2, 3, 4... until the first vehicle is detected passing coil 3, the controller will 1 in the sequence is deleted, and then when an incoming vehicle passes the double induction coil 2, a number is added at the end of the sequence, and when a vehicle exits passes the coil 3, a number is deleted at the beginning of the sequence, forming a dynamic vehicle sequence. The speed in the VMS logo display always shows the vehicle speed of the vehicle represented by the first number in the sequence, that is, the vehicle speed of the first vehicle after the stop line.

After the double induction coil 2 obtains the entry time point of the vehicle, the central controller automatically calculates the gap between the straight vehicles, and calculates the vehicle gap between the vehicles represented by the first two numbers in the vehicle sequence, that is, the first two vehicles behind the stop line. The vehicle clearance t of the vehicle is compared with the absolute safety vehicle clearance T. When t is less than T, the color-changing vehicle in VMS will flash red, indicating that left-turning vehicles are prohibited from passing. When t is greater than or equal to T, the color-changing vehicle will display Flashing yellow means that vehicles turning left are advised to pass carefully; the vehicle speed always displays the speed of the first vehicle behind the stop line (in kilometers per hour), which is directly displayed in digital form to assist left-turning drivers to make judgments.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, some improvements and replacements can also be made, these improvements and replacements It should also be regarded as the protection scope of the present invention.

Claims (10)

1. acquisition of information delivery system that guides left turning vehicle to pass through the crossing is characterized in that this system comprises: central controller, first sensor, the second sensor and display device:

Described central controller is connected with display device with first sensor, the second sensor respectively, for the treatment of the work of vehicular traffic information and each ingredient of control system;

Described first sensor is positioned at subtend Through Lane stop line T*V distance, is used for obtaining entry time point and the speed of operation of the through vehicles that enters the crossing; Wherein T is the vehicle gap that is perfectly safe, and described T is greater than inserting the crack, workshop; V is the design speed of affiliated road;

Described the second sensor is positioned at subtend Through Lane stop line place, for detection of the through vehicles that rolls away from;

Described display device is used for showing subtend Through Lane information of vehicles.

2. system as claimed in claim 1 is characterized in that this system also comprises the 3rd sensor, and described the 3rd sensor is connected with central controller, is positioned at left turn lane stop line predeterminable range place, for detection of whether there being left turning vehicle.

3. system as claimed in claim 2 is characterized in that described the 3rd sensor is inductive coil.

4. system as claimed in claim 1 is characterized in that, described first sensor is two inductive coils, and the second sensor is inductive coil, and display device is the variable information traffic sign.

5. system as claimed in claim 4 is characterized in that, the subtend Through Lane information of vehicles that described variable information traffic sign shows comprises: the text prompt information of top, middle changeable colour vehicle, and the vehicle speed of below.

6. system as claimed in claim 5 is characterized in that described changeable colour vehicle shows red sudden strain of a muscle, and no through traffic for the expression left turning vehicle, and vehicle shows yellow the sudden strain of a muscle, and expression suggestion left turning vehicle is carefully current.

7. system as claimed in claim 1 is characterized in that described T=5.5+1.96* σ, σ are the standard deviation of normal distribution.

8. system as claimed in claim 7 is characterized in that the span of described σ is [1,2].

9. acquisition of information dissemination method that guides left turning vehicle to pass through the crossing is characterized in that the method comprises:

S1, first sensor obtain entry time point and the speed of operation of the through vehicles that enters the crossing, and information is sent to controller;

S2, central controller will enter the through vehicles of crossing and give in order numbering, and control display equipment shows the speed of a motor vehicle of first numbering representative vehicle; To number simultaneously adjacent through vehicles entry time point subtracts each other and obtains the vehicle time interval, and judge first the numbering with second the numbering vehicle the vehicle time interval whether less than the vehicle gap that is perfectly safe, if, then control display equipment shows left turning vehicle no through traffic information, otherwise control display equipment shows suggestion left turning vehicle traffic information;

S3, the second sensor detect the vehicle that rolls Through Lane away from, and central controller makes zero the through vehicles numbering of rolling away from, and no longer participation information detects, and the information of vehicles of the next numbering of control display equipment issue.

10. method as claimed in claim 9, it is characterized in that, comprise also before the described step S1 whether the detection of the 3rd sensor exists left turning vehicle, if there is not left turning vehicle, central controller controls display device display screen is in closed condition, if there is left turning vehicle, the step that central controller controls display device display screen is activated.