Method for forming continuous flow of small-volume straight-right mixed vehicles at intersections under the Internet of Things

Abstract

The present invention relates to a method for forming a continuous flow of small-volume straight-right mixed vehicles at an intersection under the Internet of Things, comprising the following steps: S1, setting the desired control speed of vehicles in the direction of the intersection entrance; S2, setting the control section and road section; S3, controlling the area and the process of passing through the control area; S4, setting the minimum stopping sight distance between vehicles; S5, defining the conflict area between vehicles; S6, determining the optimal motion state process and the minimum arrival time of the vehicle; S7, determining the occupation time of the conflict area; S8, predicting the conflict between vehicles; S9, determining the speed control strategy of non-opposite vehicles; S10, regulating the vehicle according to the data obtained in step S4-S5. The present invention is suitable for small-volume intersections with straight-right mixed lanes at the entrance, reducing the time loss in the case of stopping and waiting at the intersection and slowing down and the conflict time of the physical area of ​​the intersection, increasing the operation speed and traffic efficiency of the intersection, and alleviating the traffic congestion problem of key nodes in the city.

Description

Technical Field

[0001] The present invention relates to the field of vehicle-road collaboration technology, and more specifically, to a method for forming a continuous flow of small-volume straight-right mixed vehicles at an intersection under the Internet of Things. Background Art

[0002] The development of vehicle-road collaboration and the Internet of Things technology has provided new perspectives and solutions for intersection management. By comprehensively applying modern communication technology, high-speed computing power, and high-precision sensor technology, it realizes real-time dynamic monitoring of vehicle driving status. The system can track the vehicle's position, speed, and other key driving parameters in real time. By integrating and analyzing these real-time data, the vehicle-road collaboration system can pre-adjust the vehicle's driving strategy before the vehicle approaches the intersection. For example, the system can notify the driver to slow down or speed up in advance, complete the allocation of time and space road rights, avoid potential conflicts, and optimize traffic flow. This intelligent regulation not only reduces vehicle conflicts at intersections, but also significantly improves traffic efficiency.

[0003] At intersections with low traffic volume, due to low traffic density, common problems include insufficient sight distance and unclear signs and markings, which require drivers to slow down or even stop to ensure safety when passing through the intersection, thus seriously affecting the smoothness and safety of traffic. In particular, in the straight right lane, straight and right-turning vehicles are more likely to conflict, greatly increasing safety risks. There is no control method for small-volume straight-right mixed vehicles at intersections in the prior art. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for safe, high-speed continuous flow of straight-right mixed traffic at a small-volume intersection consisting of automatic driving and natural human driving.

[0005] The technical solution adopted by the present invention to solve the technical problem is: constructing a method for forming a continuous flow of small-volume straight-right mixed vehicles at an intersection under the Internet of Things, comprising the following steps:

[0006] S1. Set the expected control speed of vehicles entering the intersection. The intersection is a symmetrical intersection with four entrance directions: east entrance, south entrance, west entrance and north entrance. Each entrance vehicle consists of straight-going and right-turning vehicles. To ensure that vehicles can pass through the intersection safely, quickly and continuously, set the expected speed v of vehicles entering the intersection. 期 , unit is m / s;

[0007] S2. Set control sections and sections;

[0008] A control section 1 is set in the physical area of ​​the intersection. The control section 1 is the extension of the right side marking line of the outermost straight right lane in each entrance direction of the intersection in the physical area of ​​the intersection. Straight-going and right-turning vehicles should maintain the expected speed of the vehicle when passing through the control section 1. The control sections 1 in each entrance direction of the intersection and the edge line of the right-turn curb are intertwined to form an area, which is the central area;

[0009] Control section 2 is set at the entrance direction of the intersection functional area. When the vehicle reaches control section 2, the speed must be the expected speed, and the vehicle must adapt to the speed and drive toward control section 1. The section between control section 2 and control section 1 is the adaptation section.

[0010] Control section 3 is set at the entrance direction of the intersection functional area, and the section between control section 3 and control section 2 is set as the straightening section, and the vehicle speed is adjusted to the expected speed in the straightening section;

[0011] Control section 4 is set at the entrance direction of the functional area of ​​the intersection; when the vehicle arrives at control section 4, the roadside control system interacts with the vehicle and requires the right-turning vehicle in the mixed traffic to turn on the turn signal. The roadside sensing device determines whether the vehicle is going straight or turning right and collects the position and speed information of the corresponding vehicle based on this; the section between control section 4 and control section 3 is the sensing pre-control section;

[0012] S3, control areas and processes through control areas;

[0013] Vehicles on the entrance road of each direction of the intersection pass through control section 4, control section 3, control section 2 and control section 1 in sequence. The central area, adaptation section, rectification section and perception pre-control section formed between the sections are collectively called the control area. Vehicles are not allowed to overtake in the control area. The process of vehicles passing through the control area is as follows: (1) Vehicle i arrives at control section 4 and enters the perception pre-control section. The speed of the vehicle is Location Information Initial moment And whether it is a right-turning vehicle sensed by the road test facility, the road test control system formulates a corresponding strategy; (2) the vehicle accepts the control of the speed control strategy in the sensing pre-control section and the rectification section, and passes through the sensing pre-control section and the rectification section without stopping with certain speed control measures; (3) the vehicle reaches the control section 2 at the expected speed, and adapts to the speed through the adaptation section to reach the control section 1; (4) the vehicle stabilizes the vehicle speed in the control section 1 and passes through the comprehensive conflict area;

[0014] S4. Set the minimum parking sight distance between vehicles;

[0015] S5. Define the conflict area between vehicles;

[0016] S6, determining the optimal motion state process of the vehicle and the minimum time to reach it;

[0017] S7. Determine the occupation time of the conflict area;

[0018] S8, predicting conflicts between vehicles;

[0019] S9, determining a speed control strategy for non-oncoming vehicles;

[0020] S10. Control the vehicle according to the data acquired in steps S4-S5.

[0021] According to the above scheme, in step S1, the expected speed v is set according to the road standard conditions. 期 The methods for applying constraints include:

[0022] S11, the constraint of the maximum road speed on the expected speed;

[0023] S12, the constraints of the expected speed on the basic road capacity calculation; the constraints of the vehicle speed v on the basic road capacity calculation model C car Take the derivative and set it to 0, solve the equation to get the control speed v under small flow continuous flow car Recommended value; the specific formula of the calculation model is shown in the following formula (1):

[0024]

[0025] Where: C is the theoretical vehicle capacity, in veh / h; h is the headway, in m; v car is the driving speed, in m / s;

[0026] S13, the right-turning vehicle is subject to the turning radius limit on the expected speed; the running trajectory of the right-turning vehicle is an arc along the curb. The maximum safe speed of the right-turning vehicle along the curb is calculated according to the ramp transition curve design specification, as shown in the following formula (2):

[0027]

[0028] Where:

[0029] v 右 is the maximum speed of a right-turning vehicle limited by the turning radius, in m / s; R is the radius of the circular curve, which is the radius of the curb at the intersection, in m; μ is the lateral force coefficient; i is the superelevation, "+" is used when setting the superelevation, and "-" is used when setting the directional superelevation;

[0030] The expected speed of each incoming vehicle at the intersection should meet the recommended value v when the road capacity is maximum. car , and should be less than or equal to the turning speed v subject to the right turn constraint 右 , and at the same time less than or equal to the maximum speed v of the roads in each import direction maxThe control speed of the expected speed of each incoming vehicle at the intersection is shown in the following formula (3):

[0031] v 期 =min(v car ,v 右 ,v max ) (3).

[0032] According to the above scheme, in step S2, the adaptation segment length L AD Affected by vehicle speed and adaptation time, the calculation process is shown in the following formula (4):

[0033] L AD =nv 期 t AD (4)

[0034] Where: n is the safety factor, which takes the value in [1, +∞); t AD is the minimum adaptation time, in seconds;

[0035] The length of the rectifier section L R Affected by the maximum acceleration, the calculation process is shown in formula (5):

[0036]

[0037] Where: v min is the minimum possible speed of a mixed right-traveling vehicle reaching the control section 3, which is 0 m / s; a max It is the maximum acceleration under human comfort conditions, in m / s 2 ;

[0038] The length of the sensing pre-control section L P Affected by the maximum acceleration, the calculation process is shown in formula (6):

[0039]

[0040] Where: v max is the maximum driving speed of the roads in each import direction.

[0041] According to the above scheme, in step S3, the process of the vehicle passing through the control area includes:

[0042] (1) Vehicle i arrives at control section 4 and enters the perception pre-control section. The vehicle's speed Location Information Initial moment And whether the right-turning vehicle is sensed by the road test facility, the road test control system formulates a corresponding strategy;

[0043] (2) The vehicle is regulated by the speed control strategy in the sensing pre-control section and the rectification section, and passes through the sensing pre-control section and the rectification section without stopping with certain speed control measures;

[0044] (3) The vehicle reaches control section 2 at the expected speed, and adapts to the speed to reach control section 1 through the adaptation section;

[0045] (4) The vehicle stabilizes its speed at control section 1 and passes through the comprehensive conflict area.

[0046] According to the above scheme, in step S4, the front vehicle is vehicle j, the rear vehicle is vehicle i, and the stopping sight distance calculation process is shown in formula (7):

[0047]

[0048] Where: v i is the driving speed of vehicle i; t is the driver’s reaction time; is the longitudinal friction coefficient between the road surface and the tire; S0 is the safety distance.

[0049] According to the above scheme, in step S5, when vehicle i enters the perception pre-control section, and its trajectory extension line intersects or overlaps with the trajectory extension line of other vehicles j in the control area, there is a conflict area between vehicle i and vehicle j; the conflict area includes the conflict area between straight vehicles in adjacent import directions and the conflict area between right-turning vehicles and straight vehicles in adjacent import directions.

[0050] According to the above scheme, in step S6, the method for determining the optimal motion state process and the minimum reaching time of the vehicle includes:

[0051] S61, initial speed when the vehicle reaches control section 4 Greater than v 期 At this time, the optimal motion state of the vehicle is: when the vehicle passes through control section 4, it continues to travel at a constant speed for a distance, then decelerates at the maximum deceleration to reach the desired speed, so that the vehicle reaches the desired speed just when it reaches control section 2, and then maintains a constant speed until it passes through the conflict area;

[0052] S62, when the vehicle reaches the initial speed of control section 4 Less than v 期 At this time, the optimal motion state of the vehicle is: when the vehicle passes through the control section 4, it immediately accelerates at the maximum acceleration until the speed reaches v 期 Then, the vehicle will maintain a constant speed until it passes through the conflict area. When the vehicle moves in the optimal motion process, it will reach the conflict area in the shortest time and pass through the conflict area.

[0053] When there is a conflict area between the vehicle and other vehicles, vehicle i reaches the conflict area section x in the best motion state. i-c The required time is the minimum arrival time; then the minimum arrival time of vehicle i is Including the speed change time during vehicle speed change and the constant speed time when driving at a constant speed Minimum arrival time The calculation of is shown in formula (8);

[0054]

[0055] Among them, the speed change time The calculation of is shown in formula (9),

[0056]

[0057] The calculation of is shown in formula (10):

[0058]

[0059] Where:

[0060] is the corresponding speed change distance in the speed change process, and the calculation formula is shown in formula (11):

[0061]

[0062] l 右转 is the turning trajectory curve length of the right-turning vehicle, in meters; L P , L R and L AD They are the lengths of the perception pre-control section, the rectification section, and the adaptation section, respectively, in meters.

[0063] According to the above scheme, in step S7, the method for determining the conflict area occupation time includes:

[0064] For conflicts between vehicles going straight in adjacent entrance directions, when the vehicle reaches control section 2, it has already maintained the expected speed of the intersection. The vehicle's occupation time in the conflict area is As shown in formula (12):

[0065]

[0066] Where: is the lane width of the vehicle that conflicts with vehicle i, in meters; l i is the length of vehicle i, in meters; ΔT is the reserved error of the time required for the vehicle to pass through the conflict area, in seconds;

[0067] For conflicts between right-turning vehicles and straight-moving vehicles in the adjacent entrance direction, the vehicle reaches x i-c To ensure safety, the distance between the surrounding vehicles and the vehicle should not be less than the minimum stopping sight distance; convert the distance into the headway time T secure That is, the time that the vehicle occupies the conflict area, which is calculated as shown in formula (13):

[0068]

[0069] Where: v i is the speed of vehicle i. Since the vehicle has maintained the desired speed when passing through control section 2, v i =v 期 ;

[0070] According to the initial time and the minimum arrival time of vehicles in the dynamic zone Get the starting time of the vehicle occupying the conflict area As shown in formula (14):

[0071]

[0072] Where, T i The section x where vehicle i reaches the conflict area i-c The time required for the vehicle i to reach the conflict area section x in the best motion state i-c hour,

[0073] Combined with the above vehicle occupation time of the conflict area, the end time of the vehicle's occupation of the conflict area is calculated As shown in formula (15):

[0074]

[0075] According to the above scheme, in step S9, determining the speed control strategy for non-oncoming vehicles includes eliminating conflicts between non-oncoming vehicles, boundary conditions for the vehicle speed control strategy, and determining the vehicle speed control strategy.

[0076] According to the above scheme, in step S10, the vehicle control method includes:

[0077] Step 1: When vehicle i reaches control section 4, the vehicle's speed Location Information Initial moment The road test facility senses information such as whether the right turn signal is turned on; based on the vehicle's turn signal status and initial speed, it is determined whether the vehicle is a right-turning vehicle and whether the initial speed is greater than the expected speed, thereby determining the corresponding optimal motion process of vehicle i;

[0078] Step 2: Assume that the vehicle executes the corresponding optimal motion process control, and predicts the conflict between it and other controlled vehicles; if there is no conflict, execute Step 3; if there is a conflict, execute Step 4;

[0079] Step 3: The vehicle immediately performs optimal motion process control and marks the vehicle as controlled;

[0080] Step 4: If there is a conflict between vehicles, calculate the overlapping time length TD ij , when vehicle i arrives at the conflict area, it is delayed by TD ij , the conflict between vehicle i and other vehicles can be eliminated; according to the overlapping time length TD ij The speed control strategy is designed for the vehicle in step S9, and the speed control strategy is executed in the sensing pre-control section and the rectification section, so that the vehicle can eliminate the conflict by accelerating and decelerating, and finally maintain the desired speed at the control section 2 to pass through the central area; it must be noted that: when the calculated TD ij When it is greater than T3-T0, the speed control strategy must include a stop waiting time. At this time, it exceeds the scope of small traffic and is not considered.

[0081] The method for forming a continuous flow of small-volume straight-right mixed vehicles at an Internet of Things intersection according to the present invention has the following beneficial effects:

[0082] 1. Based on the research object of straight-right mixed traffic flow at intersections, the present invention proposes a method for forming and regulating straight-right mixed continuous traffic flow under low traffic conditions using vehicle-road cooperative technology, clarifies the road right allocation between vehicles, enables vehicles to form a continuous flow, and ensures the safety and efficiency of the continuous flow when passing through the intersection. This method not only improves the safety of the intersection, but also enhances the overall efficiency of the traffic system, allowing the intersection to maintain efficient operation even under low traffic conditions.

[0083] 2. The present invention is applicable to small traffic intersections with mixed straight and right lanes at the entrance, and has no strict requirements on the number of lanes in each entrance direction of the intersection and the type of motor vehicles. If a vehicle needs to go straight or turn right through the intersection, it can pass through the physical area of ​​the intersection without stopping by using the content of the invention, breaking the traditional traffic mode of waiting for release at the stop line, greatly improving the traffic efficiency of the intersection while ensuring safe passage, and creating a new direction of distributed traffic control for continuous driving of cross-conflicting traffic, which has extremely high scientific and application value.

[0084] 3. The present invention reduces the time loss caused by waiting and slowing down at intersections and the conflict time of the physical area of ​​the intersection, increases the operation speed and traffic efficiency of the intersection, and alleviates the traffic congestion problem at key nodes in the city. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0086] Figure 1 It is a schematic diagram of the regulation section and control area;

[0087] Figure 2 A schematic diagram of the conflict area between straight-moving vehicles;

[0088] Figure 3 A schematic diagram of the conflict area between straight-moving and right-turning vehicles;

[0089] Figure 4 is the initial speed Greater than v 期 Schematic diagram of the optimal motion state of the vehicle when ;

[0090] Figure 5 is the initial speed Less than v 期 Schematic diagram of the optimal motion state of the vehicle when ;

[0091] Figure 6 This is a schematic diagram of overlapping time. DETAILED DESCRIPTION

[0092] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0093] like Figure 1-6 As shown, the method for forming a continuous flow of small-volume straight-right mixed vehicles at an intersection under the Internet of Things of the present invention includes the following steps:

[0094] Step 1: Set the desired control speed for vehicles entering the intersection

[0095] The intersection is a symmetrical intersection with four entrance directions, namely the east entrance, south entrance, west entrance and north entrance. Among them, the east-west entrance (or north-south entrance) are opposite entrances. The remaining two combinations of different entrances are called non-opposite entrances, such as the east entrance and the south entrance, the east entrance and the north entrance, etc. Each entrance vehicle consists of straight-going and right-turning vehicles. In order to ensure that vehicles can pass through the intersection safely, quickly and continuously, the expected control speed v of the vehicles in the intersection entrance direction is set 期 , unit is m / s.

[0096] The expected control speed v according to the road standard conditions 期 The constraints are as follows.

[0097] 1.1 Constraints of the maximum road speed on the desired speed

[0098] The maximum road speed refers to the highest speed that a vehicle can reach under actual road and traffic conditions. This speed may be affected by many factors, such as road conditions, traffic flow, weather conditions, etc. You can obtain information on the maximum driving speed by consulting relevant traffic regulations or traffic management departments.

[0099] 1.2 Constraints on the expected speed in calculating basic road capacity

[0100] According to the basic road capacity calculation model C, the vehicle speed v car Take the derivative and set it to 0, solve the equation to get the control speed v under small flow continuous flow car The specific formula of the calculation model is shown in the following formula (1).

[0101]

[0102] Where:

[0103] C is the theoretical vehicle capacity, in veh / h;

[0104] h is the headway between vehicles, in meters;

[0105] v car is the vehicle speed in m / s.

[0106] 1.3 The desired speed of a right-turning vehicle is limited by the turning radius

[0107] The running trajectory of a right-turning vehicle is an arc along the curb. The maximum safe speed of a right-turning vehicle along the curb can be calculated based on the ramp transition curve design specifications, as shown in the following formula (2).

[0108]

[0109] Where:

[0110] v 右 The maximum speed of a right-turning vehicle limited by the turning radius, in m / s;

[0111] R is the radius of the circular curve, here it is the radius of the intersection curb, in meters;

[0112] μ is the lateral force coefficient;

[0113] i stands for superelevation. Use “+” to set superelevation and use “-” to set directional superelevation.

[0114] The expected speed of each incoming vehicle at the intersection should meet the recommended value v when the road capacity is maximum. car , and should be less than or equal to the turning speed v subject to the right turn constraint 右, and at the same time less than or equal to the maximum speed v of the roads in each import direction max The control speed of the expected speed of each incoming vehicle at the intersection is shown in the following formula (3).

[0115] v 期 =min(v car ,v 右 ,v max ) (3)

[0116] Step 2: Set control sections and sections

[0117] 2.1 Set control section 1 and central area

[0118] Control section 1 is set in the physical area of ​​the intersection. Control section 1 is the extension of the right side marking line of the outermost straight right lane in each entrance direction of the intersection in the physical area of ​​the intersection. Straight-going and right-turning vehicles should maintain the expected speed of the vehicle when passing through control section 1. Control section 1 in each entrance direction of the intersection and the right-turn curb edge line will interweave to form an area, which is called the central area.

[0119] 2.2 Setting Control Section 2 and Adaptation Section

[0120] In order to maintain the stability of speed, a control section 2 is set at the entrance direction of the intersection functional area. When the vehicle reaches the control section 2, the speed must be v 期 , and adapt to the speed to drive towards control section 1. The section between control section 2 and control section 1 is called the adaptation section. The length of the adaptation section L AD Affected by vehicle speed and adaptation time, the calculation process is shown in Equation 4:

[0121] L AD =nv 期 t AD (4)

[0122] Where:

[0123] n is the safety factor, which ranges from [1, +∞);

[0124] t AD is the minimum adaptation time, in seconds.

[0125] 2.3 Setting the control section Sanhe rectifier section

[0126] Control section 3 is set at the entrance direction of the intersection functional area, and the section between control section 3 and control section 2 is called the straightening section. Vehicles in the straightening section take a certain acceleration to adjust the speed to the expected speed according to the corresponding strategy. The length of the straightening section L R Affected by the maximum acceleration, the calculation process is shown in formula (5).

[0127]

[0128] Where:

[0129] v min The minimum possible speed for a straight-right mixed traffic vehicle to reach the third control section is 0m / s;

[0130] a max It is the maximum acceleration under human comfort conditions, generally within [-5, +5], in m / s 2 .

[0131] 2.4 Setting the control section 4 and the perception pre-control section

[0132] Control section 4 is set at the entrance direction of the intersection functional area. When the vehicle arrives at control section 4, the roadside control system interacts with the vehicle and requires the right-turning vehicle in the mixed traffic to turn on the turn signal. The roadside sensing equipment determines whether the vehicle is going straight or turning right and collects information such as the position and speed of the corresponding vehicle. Subsequently, the roadside coordination control unit will conduct an in-depth analysis of this data and optimize the vehicle's trajectory. Based on the system's accurate prediction of vehicle behavior and real-time intelligence, the best strategy will be formulated to regulate the vehicle's driving behavior. The section between control section 4 and control section 3 is called the perception pre-control section.

[0133] The length of the sensing pre-control section L P Affected by the maximum acceleration, the calculation process is shown in formula (6).

[0134]

[0135] Where:

[0136] v max is the maximum driving speed of the roads in each import direction.

[0137] 2.5 Analysis of the length of the rectification section and the sensing pre-control section

[0138] The straightening section and the sensing pre-control section are the sections that the vehicle travels during the speed change process, and their lengths must meet the length required for the vehicle to change speed. The lengths of the straightening section and the sensing pre-control section assume that the vehicle starts to accelerate from the initial state (initial speed is 0) until it leaves the section and the speed just reaches the expected speed and the maximum driving speed of the entrance road. Therefore, the lengths of the sensing pre-control area and the straightening section can meet the speed change process of the vehicle.

[0139] Step 3: Control Areas and Flow Through Control Areas

[0140] Vehicles on the entrance roads of each direction of the intersection pass through control sections 4, 3, 2 and 1 in sequence. The central area, adaptation section, rectification section and perception pre-control section formed between the sections are collectively referred to as the control area. Figure 1 As shown in the figure, vehicles are not allowed to overtake in the control area. The process of vehicles passing through the control area is as follows: (1) Vehicle i arrives at control section 4 and enters the perception pre-control section. The speed of the vehicle Location Information Initial moment And whether it is a right-turning vehicle sensed by the road test facilities, the road test control system formulates a corresponding strategy; (2) the vehicle accepts the control of the speed control strategy in the perception pre-control section and the straightening section, and passes through the perception pre-control section and the straightening section without stopping with certain speed control measures; (3) the vehicle reaches control section two at the expected speed, and adapts to the speed through the adaptation section to reach control section one; (4) the vehicle stabilizes the vehicle speed in control section one and passes through the comprehensive conflict area.

[0141] Step 4: Minimum stopping sight distance between vehicles

[0142] The stopping sight distance between vehicles is to ensure that braking can be performed in an emergency to avoid collision with the vehicle in front. That is, the stopping sight distance is the distance traveled by the driver's reaction time plus the distance traveled by the braking time and a certain safety distance. It should be noted that after the vehicle passes through the central area, it will not be within the control range of the control system. Taking the front vehicle as vehicle j and the rear vehicle as vehicle i as an example, the calculation process of the stopping sight distance is shown in formula (7):

[0143]

[0144] Where:

[0145] v i is the speed of vehicle i; t is the driver’s reaction time, which is generally 2.0s. If all vehicles are self-driving vehicles, the reaction time can be reduced according to the characteristics of self-driving vehicles. In mixed driving state, the value is taken according to human driving;

[0146] is the longitudinal friction coefficient between the road surface and the tire;

[0147] S0 is the safety distance, and it is recommended to be determined according to the latest intersection design standards.

[0148] Step 5: Defining the conflict area between vehicles

[0149] When vehicle i enters the perception pre-control section, and its trajectory extension line intersects or overlaps with the trajectory extension line of other vehicles j in the control area, there is a conflict area between vehicles i and j. There are two types of conflict areas.

[0150] 5.1 Conflict area between vehicles going straight in adjacent entrance directions

[0151] A conflict area will be formed between the straight vehicles in the adjacent entrance directions. The length and width of the conflict area are the width of the lanes where the two vehicles are located. Figure 2 shown.

[0152] 5.2 Conflict area between right-turning vehicles and vehicles going straight in the adjacent entrance direction

[0153] A conflict zone will be formed between the right-turning vehicle and the straight-moving vehicle in the adjacent entrance direction. That is, when the right-turning vehicle completes the right turn and merges into the adjacent straight-moving lane, in order to ensure safety, the front and rear vehicles should maintain a safe headway, as shown in the following figure. Figure 3 At this time, the length of the conflict area is the minimum parking sight distance between vehicles, and the width is the lane width.

[0154] Since the control area may include multiple vehicles, there will be multiple conflict areas containing vehicle i. To avoid conflicts between vehicles, each conflict area is allowed to be occupied by at most one vehicle at any time, so conflicting vehicles must wait for the previous vehicle to pass through the conflict area before arriving at the conflict area. The cross-sectional position of each conflict area closest to vehicle i is recorded as x i-c , where the conflict area between the right-turning vehicle and the straight-moving vehicle in the adjacent entrance direction shows that: i-c Fixed to the boundary section where the vehicle leaves the center area.

[0155] Step 6: Vehicle optimal motion state process and minimum reaching time

[0156] According to the comparison between the initial speed and the expected speed, the optimal motion state of the vehicle can be divided into two cases.

[0157] 6.1 Initial speed of vehicle when it reaches control section 4 Greater than v 期

[0158] At this time, the optimal motion state of the vehicle is: when the vehicle passes through control section 4, it continues to travel at a constant speed for a distance, then decelerates at the maximum deceleration to reach the desired speed, so that the vehicle reaches the desired speed just when it reaches control section 2, and then maintains a constant speed until it passes through the conflict area, as shown in the figure below. Figure 4 shown.

[0159] 6.2 Initial speed of vehicle arriving at control section 4 Less than v 期

[0160] At this time, the optimal motion state of the vehicle is: when the vehicle passes through the control section 4, it immediately accelerates at the maximum acceleration until the speed reaches v 期Then keep driving at a constant speed until you pass the conflict area. Figure 5 When the vehicle moves in the optimal motion process, it will reach the conflict area in the shortest time and pass through the conflict area.

[0161] When there is a conflict area between the vehicle and other vehicles, vehicle i reaches the conflict area section x in the best motion state. i-c The required time is the minimum arrival time. Then the minimum arrival time of vehicle i is Including the speed change time during vehicle speed change and the constant speed time when driving at a constant speed Minimum arrival time The calculation of is shown in formula (8).

[0162]

[0163] Among them, the speed change time The calculation of is shown in formula (9),

[0164]

[0165] The calculation of is shown in formula (10):

[0166]

[0167] Where:

[0168] is the corresponding speed change distance in the speed change process, and the calculation formula is shown in formula (11).

[0169]

[0170] lRight turn is the length of the turning trajectory curve of the right-turning vehicle, in meters;

[0171] L P , L R and L AD are the lengths of the sensing pre-control section, rectification section, and adaptation section, respectively, in meters;

[0172] Step 7: Conflict Area Occupancy Time

[0173] For conflicts between vehicles going straight in adjacent entrance directions, when the vehicle reaches control section 2, it has already maintained the expected speed of the intersection. The vehicle's occupation time in the conflict area is As shown in formula (12).

[0174]

[0175] Where:

[0176] is the lane width of the vehicle that conflicts with vehicle i, in meters;

[0177] l i is the length of vehicle i, in meters;

[0178] ΔT is the reserved error of the time required for the vehicle to pass through the conflict area, in seconds. When the vehicle passes through the intersection strictly according to the regulated speed, the corresponding error Δt is 0. In general, it is set according to the specific operating environment.

[0179] For conflicts between right-turning vehicles and straight-moving vehicles in the adjacent entrance direction, the vehicle reaches x i-c To ensure safety, the distance between the surrounding vehicles and the vehicle should not be less than the minimum stopping sight distance. Convert this distance into the headway T secure That is, the time that the vehicle occupies the conflict area, which is calculated as shown in formula (13).

[0180]

[0181] Where: v i is the speed of vehicle i. Since the vehicle has maintained the desired speed when passing through control section 2, v i =v 期 .

[0182] According to the initial moment in step 3 and the minimum arrival time of the vehicle in step 6 to the dynamic area The starting time of the vehicle occupying the conflict area can be obtained As shown in formula (14).

[0183]

[0184] Where, T i The section x where vehicle i reaches the conflict area i-c The time required. When vehicle i reaches the conflict area section x in the best motion state i-c hour,

[0185] Combined with the above vehicle occupation time of the conflict area, the end time of the vehicle's occupation of the conflict area can be calculated As shown in formula (15).

[0186]

[0187] Step 8: Vehicle-to-vehicle conflict prediction

[0188] Based on steps 4 to 7, the conflict between vehicles can be predicted. According to the different import directions of the vehicles, the objects involved in the conflict between vehicles can be divided into three categories: vehicles in a single import direction, vehicles in opposite import directions, and vehicles in non-opposite import directions.

[0189] The conflict prediction between vehicles can be divided into the following categories:

[0190] 8.1 Conflict Prediction between Vehicles in a Single Import Direction

[0191] There is a following relationship between vehicles in the same lane in a certain import direction. To ensure safety, the headway time T of the following vehicle is h Should not be less than the headway time T corresponding to the stopping sight distance secure , whose calculation formula is shown in the above formula (13). When the vehicle is driving in the optimal motion state, the headway between it and other vehicles in the same lane will be less than T secure If the situation is such, it is considered that there is a conflict between the vehicles.

[0192] It is worth noting that when a certain entrance direction contains multiple through lanes, and there is no through vehicle in at least one through lane, the next through vehicle entering the entrance direction is not considered to be in the same lane as other through vehicles, because the vehicle can be adjusted to the through lane without through vehicles through a short lane change process, and thus does not have a following relationship with other vehicles in the same lane.

[0193] 8.2 Conflict Prediction between Oncoming Vehicles

[0194] Since there is no conflict area or following relationship between vehicles in the object's entrance direction, the movements of the two are relatively independent, and safety can be maintained under any conditions, and there will be no conflict between vehicles.

[0195] 8.3 Conflict Prediction between Non-Opposite Imported Vehicles

[0196] There is a conflict area between non-opposite import vehicles. The main conflict between vehicles is that the occupation time of the conflict area cannot overlap. Therefore, the next vehicle is allowed to occupy the conflict area only after the previous vehicle releases the occupation of the conflict area. For example, the front vehicle is vehicle j and the rear vehicle is vehicle i, and the two vehicles maintain the best motion process. The time when the rear vehicle arrives at the conflict area Should be greater than the time when the front car leaves the conflict area Otherwise, it is considered that there is a conflict. The condition for avoiding conflict between non-opposite vehicles is shown in formula (16).

[0197]

[0198] Step 9: Speed ​​control strategy for non-oncoming vehicles

[0199] The non-oncoming vehicle speed control strategy includes non-oncoming vehicle conflict elimination, vehicle speed control strategy boundary conditions and determination of vehicle speed control strategy.

[0200] 9.1 Elimination of conflicts between non-oncoming vehicles

[0201] When all vehicles are running in the best state of motion, conflicts may occur between vehicles. For example, vehicles in a single import direction cannot meet the safe headway requirements; or vehicles in non-opposite directions have a situation where the previous vehicle has not yet released the occupation of the conflict area, while the next vehicle has already started to occupy the conflict area. In both cases, a conflict area is repeatedly used within a certain period of time, as shown in the attached Figure 6 As shown. Then the overlapping time length TD when vehicle i and vehicle j use the public area is ij , as shown in formula (17).

[0202]

[0203] When vehicle i arrives at the conflict area, it is delayed by TD ij , then the conflict between vehicle i and vehicle j can be eliminated. Since vehicle i may conflict with multiple vehicles, in order to ensure that multiple conflicts can be eliminated, the delay time of vehicle i arriving at the conflict area should be greater than the length of all repeated times. That is, the minimum delay time TD of vehicle i arriving at the conflict area without conflict is min , which is equal to the maximum overlapping time length of the conflicting vehicle i and any vehicle k, as shown in formula (18).

[0204] TD min =max{TD ik},k∈N * (18)

[0205] 9.2 Vehicle Speed ​​Control Strategy Selection Conditions

[0206] According to the initial speed of the vehicle passing through the control section Develop corresponding speed control strategies based on the size of the

[0207] 9.2.1 Initial velocity Less than the expected speed v 期

[0208] There are three vehicle speed control strategies, namely strategy 1, strategy 2 and strategy 3. Strategy 1: After passing through control section 4, the vehicle accelerates at a constant acceleration, and then drives at a constant speed after accelerating to the desired speed. Strategy 2: After passing through control section 4, the vehicle first drives at a constant speed for a period of time, and then accelerates to the desired speed at a constant acceleration when it reaches control section 2. Strategy 3: The vehicle decelerates at a constant deceleration in the perception pre-control section, and after passing through control section 3, it accelerates to the desired speed at a constant acceleration when it reaches control section 2.

[0209] The boundary conditions between adjacent strategies are given below.

[0210] (1) Benchmark passing time for optimal motion state

[0211] The vehicle passes through the perception pre-control section and the rectification section in the optimal motion state as the reference condition, and the required time is T0, as shown in formula (19).

[0212]

[0213] (2) Boundary conditions of strategy 1 and strategy 2

[0214] The boundary states of strategy 1 and strategy 2 are: the vehicle is based on the initial speed After passing through control section 4, it accelerates at a constant acceleration, and the speed just accelerates to the desired speed when reaching control section 2. In this state, the time required to pass through the sensing pre-control section and the rectification section is T1, as shown in formula (20).

[0215]

[0216] The minimum delay time TD of vehicle i arriving at the conflict area under safety conditions is min , when it is less than or equal to the difference T1-T0 between boundary condition 1 and reference condition, speed control strategy 1 can be used to regulate the vehicle; otherwise, speed control strategy 2 or 3 can be selected.

[0217] (3) Boundary conditions of strategies 2 and 3

[0218] The boundary states of strategy 2 and strategy 3 are: the vehicle is based on the initial speed After running at a constant speed for a period of time, it starts to accelerate in the optimal motion state, and the speed is just the expected speed when it reaches the control section 2. In this state, the time required to pass through the sensing pre-control section and the rectification section is T2, as shown in formula (21).

[0219]

[0220] The minimum delay time TD of vehicle i arriving at the conflict area under safety conditions is min, when it is greater than T1-T0 and less than or equal to the difference between boundary condition 2 and reference condition T2-T0, the speed control strategy 2 can be used to regulate the vehicle; otherwise, the speed control strategy 3 can be selected.

[0221] (4) Maximum driving time of strategy 3

[0222] The state when the driving time of strategy three is the longest is: after the vehicle passes through control section four, it starts to decelerate in the perception pre-control section, and the speed just decreases to 0 when it reaches control section three, and then accelerates at the maximum acceleration, and the speed just accelerates to the expected speed when the vehicle reaches control section two. In this state, the time required to pass through the perception pre-control section and the rectification section is T3, as shown in formula (22).

[0223]

[0224] In summary, based on the minimum delay time of vehicle i arriving at the conflict area under safety conditions and the three boundary conditions, the selection conditions of the vehicle speed control strategy can be obtained, as shown in formula (23).

[0225]

[0226] 9.2.2 Initial velocity Greater than the expected speed v 期

[0227] There are three vehicle speed control strategies, namely strategy 1, strategy 2 and strategy 3. Strategy 1: After passing through control section 4, the vehicle maintains a constant speed for a period of time, then decelerates at a constant deceleration, and the speed just reaches the expected speed when it reaches control section 2. Strategy 2: After passing through control section 4, the vehicle decelerates at a constant deceleration, and after decelerating to the expected speed, it maintains a constant speed to control section 2. Strategy 3: The vehicle decelerates at a constant deceleration in the perception pre-control section, and after passing through control section 3, it accelerates at a constant acceleration, reaching the expected speed before control section 2.

[0228] The boundary conditions between adjacent strategies are given below:

[0229] (1) Benchmark passing time for optimal motion state

[0230] The vehicle passes through the perception pre-control section and the rectification section in the optimal motion state as the reference condition, and the required time is T0, as shown in formula (24).

[0231]

[0232] (2) Boundary conditions of strategy 1 and strategy 2

[0233] The boundary state between strategy 1 and strategy 2 is: the vehicle starts to decelerate at a constant deceleration after passing through control section 4, and the speed just reaches the expected speed when reaching control section 2. In this state, the time required to pass through the sensing pre-control section and the rectification section is T1, as shown in formula (25).

[0234]

[0235] The minimum delay time TD of vehicle i arriving at the conflict area under safety conditions is min , when it is less than or equal to the difference T1-T0 between boundary condition 1 and reference condition, speed control strategy 1 can be used to regulate the vehicle; otherwise, speed control strategy 2 or 3 can be selected.

[0236] (3) Boundary conditions between strategies 2 and 3

[0237] The boundary state between strategy 2 and strategy 3 is: after the vehicle passes through control section 4, it starts to decelerate at the maximum deceleration, and after decelerating to the desired speed, it maintains a constant speed to control section 2. In this state, the time required to pass through the sensing pre-control section and the rectification section is T2, as shown in formula (26).

[0238]

[0239] The minimum delay time TD of vehicle i arriving at the conflict area under safety conditions is min , when it is greater than T1-T0 and less than or equal to the difference between boundary condition 2 and reference condition T2-T0, the speed control strategy 2 can be used to regulate the vehicle; otherwise, the speed control strategy 3 can be selected.

[0240] (4) Maximum driving time of strategy 3

[0241] The state when strategy three has the longest driving time is: the vehicle decelerates at a constant deceleration after passing through control section four, and the speed is just 0 when reaching control section three, and then accelerates at the maximum acceleration. The length of the rectification section can just meet the vehicle to reach the expected speed when reaching control section two. In this state, the time required to pass through the sensing pre-control section and the rectification section is T2, as shown in formula (27).

[0242]

[0243] In summary, based on the minimum delay time of vehicle i arriving at the conflict area under safety conditions and the two boundary conditions, the selection conditions of the vehicle speed control strategy can be obtained, as shown in formula (28).

[0244]

[0245] 9.3 Determine the accurate control information of the vehicle speed control strategy

[0246] Based on the selection conditions of the speed control strategy in Section 9.2, combined with TD min , the accurate control information of the vehicle’s speed control strategy can be determined.

[0247] The following are the relevant parameters to be determined for several control strategies.

[0248] 9.3.1 Initial velocity Less than the expected speed v 期

[0249] When the vehicle's initial speed Less than the expected speed v 期 When , let the time taken by the vehicle to move from control section 4 to control section 2 in the optimal motion state be T4, and its size can be calculated by formula (29).

[0250]

[0251] (1) Strategy 1 mainly determines the acceleration during acceleration, which can be obtained by solving the constraint condition (30).

[0252]

[0253] Where:

[0254] a1 is the magnitude of the acceleration of strategy one;

[0255] t1 and t2 are the times of vehicle acceleration and constant speed in strategy one.

[0256] (2) Strategy 2 mainly determines the uniform speed time and acceleration, which can be obtained by solving the constraint condition (31).

[0257]

[0258] Where:

[0259] t3 and t4 are the uniform speed and acceleration times of strategy 2, respectively;

[0260] a2 is the acceleration magnitude for strategy 2.

[0261] (3) Strategy 3 mainly determines the deceleration and acceleration, which can be obtained by solving the constraint condition (32).

[0262]

[0263] Where:

[0264] v3 is the speed of the vehicle when it passes through control section three in strategy three;

[0265] a3 and a4 are the deceleration and acceleration of strategy three respectively.

[0266] 9.3.2 Initial velocity Greater than the expected speed v 期

[0267] When the vehicle's initial speed Greater than the expected speed v 期 When , let the time taken by the vehicle to move from control section 4 to control section 2 in the optimal motion state be T5, and its size can be calculated by formula (33).

[0268]

[0269] (1) Strategy 1 mainly determines the uniform speed time and deceleration, which can be obtained by solving the constraint condition (34).

[0270]

[0271] Where:

[0272] t5 and t6 are the uniform speed and deceleration time of the vehicle in strategy 1;

[0273] a5 is the deceleration of strategy one.

[0274] (2) Strategy 2 mainly determines the deceleration, which can be obtained by solving the constraint (35).

[0275]

[0276] Where:

[0277] t7 and t8 are the deceleration and constant speed times of the vehicle in strategy 2;

[0278] a6 is the deceleration of strategy 2.

[0279] (3) Strategy 3 mainly determines the deceleration and acceleration, which can be obtained by solving the constraint condition (36).

[0280]

[0281] Where:

[0282] v4 is the speed of the vehicle when it passes through control section three in strategy three;

[0283] a7 and a8 are the deceleration and acceleration of strategy three respectively.

[0284] Step 10: The vehicle control method is as follows:

[0285] Step 1: When vehicle i reaches control section 4, the vehicle's speed Location Information Initial moment The road test facility senses information such as whether the right turn signal is turned on. According to the vehicle's turn signal status and initial speed, it can be determined whether the vehicle is a right-turning vehicle and whether the initial speed is greater than the expected speed, thereby determining the corresponding optimal motion process of vehicle i.

[0286] Step 2: Assume that the vehicle executes the corresponding optimal motion process control and predicts the conflict between it and other controlled vehicles. If there is no conflict, execute Step 3; if there is a conflict, execute Step 4.

[0287] Step 3: The vehicle immediately performs optimal motion process control and marks the vehicle as controlled;

[0288] Step 4: If there is a conflict between vehicles, calculate the overlapping time length TD ij , when vehicle i arrives at the conflict area, it is delayed by TD ij , the conflict between vehicle i and other vehicles can be eliminated. According to the overlapping time length TD ij The size of the vehicle is designed through step 9, and the speed control strategy is executed in the perception pre-control section and the rectification section, so that the vehicle can eliminate the conflict by accelerating and decelerating, and finally maintain the desired speed at the control section 2 to pass through the central area; it must be noted that: when the calculated TD ij When it is greater than T3-T0, the speed control strategy must include a stop waiting time. At this time, it exceeds the scope of small traffic and is not considered.

[0289] It should be understood that parts not elaborated in detail in this specification belong to the prior art.

[0290] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A method for forming a continuous flow of small-volume straight-right mixed vehicles at an Internet of Things intersection, characterized in that: The steps include: S1. Set the expected control speed of vehicles entering the intersection. The intersection is a symmetrical intersection with four entrance directions: east entrance, south entrance, west entrance and north entrance. Each entrance consists of straight-going and right-turning vehicles. To ensure that vehicles can pass through the intersection safely, quickly and continuously, set the expected speed of vehicles entering the intersection. , the unit is ; S2. Setting control sections and sections; A control section 1 is set in the physical area of ​​the intersection. The control section 1 is the extension of the right side marking line of the outermost straight right lane in each entrance direction of the intersection in the physical area of ​​the intersection. Straight-going and right-turning vehicles should maintain the expected speed of the vehicle when passing through the control section 1. The control sections 1 in each entrance direction of the intersection and the edge line of the right-turn curb are intertwined to form an area, which is the central area; Control section 2 is set at the entrance direction of the intersection functional area. When the vehicle reaches control section 2, the speed must be the expected speed, and the vehicle must adapt to the speed and drive toward control section 1. The section between control section 2 and control section 1 is the adaptation section. Control section 3 is set at the entrance direction of the intersection functional area, and the section between control section 3 and control section 2 is set as the straightening section, and the vehicle speed is adjusted to the expected speed in the straightening section; Control section 4 is set at the entrance direction of the functional area of ​​the intersection; when the vehicle arrives at control section 4, the roadside control system interacts with the vehicle and requires the right-turning vehicle in the mixed traffic to turn on the turn signal. The roadside sensing device determines whether the vehicle is going straight or turning right and collects the position and speed information of the corresponding vehicle based on this; the section between control section 4 and control section 3 is the sensing pre-control section; The adaptation segment length Affected by vehicle speed and adaptation time, the calculation process is shown in the following formula (4): （4） Where: is the safety factor, and its value is ; is the minimum adaptation time, in units of ; Length of rectifier section Affected by the maximum acceleration, the calculation process is shown in formula (5): （5） Where: is the minimum possible speed for a mixed right-traveling vehicle to reach the third control section, and is 0 ; is the maximum acceleration under human comfort conditions, in units of ; Length of sensing pre-control section Affected by the maximum acceleration, the calculation process is shown in formula (6): （6） Where: is the maximum speed of the roads in each import direction; S3, control areas and processes through control areas; Vehicles passing through control sections 4, 3, 2, and 1 in the entrance lanes of the intersection in each direction are called control areas. The central area, adaptation section, rectification section, and perception pre-control section formed between the sections are collectively referred to as the control area. Vehicles are not allowed to overtake in the control area. The process of vehicles passing through the control area is as follows: (1) Vehicle Arriving at control section 4 and entering the perception pre-control section, the vehicle's speed , location information , the initial moment And whether it is a right-turning vehicle detected by the road test facilities, the road test control system formulates a corresponding strategy; (2) The vehicle accepts the control of the speed control strategy in the perception pre-control section and the rectification section, and passes through the perception pre-control section and the rectification section without stopping with certain speed control measures; (3) The vehicle reaches the control section 2 at the expected speed, and adapts to the speed through the adaptation section to reach the control section 1; (4) The vehicle stabilizes the vehicle speed in the control section 1 and passes through the comprehensive conflict area; S4. Set the minimum stopping sight distance between vehicles; S5. Define the conflict area between vehicles; S6, determining the optimal motion state process of the vehicle and the minimum time to reach it; Methods for determining the optimal motion state process and the minimum time to reach the optimal motion state of the vehicle include: S61, initial speed when the vehicle reaches control section 4 Greater than At this time, the optimal motion state of the vehicle is: when the vehicle passes through control section 4, it continues to travel at a constant speed for a distance, then decelerates at the maximum deceleration to reach the desired speed, so that the vehicle reaches the desired speed just when it reaches control section 2, and then maintains a constant speed until it passes through the conflict area; S62, when the vehicle reaches the initial speed of control section 4 Less than At this time, the optimal motion state of the vehicle is: when the vehicle passes through the control section 4, it immediately accelerates at the maximum acceleration, and when the speed reaches Then, the vehicle will maintain a constant speed until it passes through the conflict area. When the vehicle moves in the optimal motion process, it will reach the conflict area in the shortest time and pass through the conflict area. When there is a conflict zone between the vehicle and other vehicles, the vehicle Reach the conflict zone section in optimal motion The required time is the minimum arrival time; then the vehicle Minimum arrival time Including the speed change time during vehicle speed change and the constant speed time when driving at a constant speed ; Minimum arrival time The calculation of is shown in formula (8); （8） Among them, the speed change time The calculation of is shown in formula (9): （9） The calculation of is shown in formula (10): （10） Where: is the corresponding speed change distance in the speed change process, and the calculation formula is shown in formula (11): （11） is the curve length of the turning trajectory of the right-turning vehicle, in units of ; , and are the lengths of the perception pre-control section, rectification section, and adaptation section, respectively, in units of ; S7. Determine the occupation time of the conflict area; Methods for determining the time occupied by a conflict zone include: For conflicts between vehicles going straight in adjacent entrance directions, when the vehicle reaches control section 2, it has already maintained the expected speed of the intersection. The vehicle's occupation time in the conflict area is As shown in formula (12): （12） Where: For vehicles The width of the lane where the conflicting vehicles are located, in ; For vehicles The length of ; The reserved error for the time required for the vehicle to pass through the conflict area, in units of ; For conflicts between right-turning vehicles and straight-moving vehicles in the adjacent entrance direction, vehicles arriving at To ensure safety, the distance between the surrounding vehicles and the vehicle should not be less than the minimum stopping sight distance; convert the distance into the headway time distance. That is, the time that the vehicle occupies the conflict area, which is calculated as shown in formula (13): （13） Where: For vehicles The vehicle has been traveling at a constant speed since it has been traveling at the desired speed when passing through the control section 2. ; According to the initial time and the minimum arrival time of vehicles in the dynamic zone , get the starting time of vehicle occupation of the conflict area , as shown in formula (14): （14） In the formula, For vehicles Reaching the conflict zone section The time required for the vehicle Reach the conflict zone section in optimal motion hour, ; Combined with the above vehicle occupation time of the conflict area, the end time of the vehicle's occupation of the conflict area is calculated , as shown in formula (15): （15）； S8, predicting conflicts between vehicles; S9, determining a speed control strategy for non-oncoming vehicles; S10, regulating the vehicle according to the data obtained in steps S4-S5; The vehicle control methods include: Step 1: Vehicle When reaching control section 4, the vehicle's speed , location information , the initial moment The road test facility senses whether the right turn signal is on and other information; based on the vehicle's turn signal status and initial speed, it determines whether the vehicle is turning right and whether the initial speed is greater than the expected speed, thereby judging the vehicle The corresponding optimal movement process; Step 2: Assume that the vehicle executes the corresponding optimal motion process control, and predicts the conflict between it and other controlled vehicles; if there is no conflict, execute Step 3; if there is a conflict, execute Step 4; Step 3: The vehicle immediately performs optimal motion process control and marks the vehicle as controlled; Step 4: If there is a conflict between vehicles, calculate the length of the overlapping time , when the vehicle Arrival at conflict zone delayed , then the vehicle can be eliminated Conflicts with other vehicles; based on the length of overlap The speed control strategy is designed for the vehicle in step S9, and the speed control strategy is executed in the perception pre-control section and the rectification section, so that the vehicle eliminates the conflict by accelerating and decelerating, and finally maintains the desired speed at the control section 2 to pass through the central area.

2. The method for forming a continuous flow of small-volume straight-right mixed vehicles at an Internet of Things intersection according to claim 1 is characterized in that: In step S1, the expected speed is set according to the road standard conditions. The methods for applying constraints include: S11, the constraint of the maximum road speed on the expected speed; S12. Constraints on the expected speed for basic road capacity calculation; Based on the basic road capacity calculation model Speed Take the derivative and set it to 0, solve the equation to get the control speed under small flow continuous flow Recommended value; the specific formula of the calculation model is shown in the following formula (1): （1） Where: is the theoretical vehicle capacity, in units of ; is the headway distance, in units of ; is the driving speed, in units of ; S13. The desired speed of a right-turning vehicle is constrained by the turning radius. The running trajectory of a right-turning vehicle is an arc along the curb. The maximum safe speed of a right-turning vehicle along the curb is calculated according to the ramp transition curve design specification, as shown in the following formula (2): （2） Where: The maximum speed of a right-turning vehicle limited by the turning radius, in units of ; is the radius of the circular curve, here it is the radius of the intersection curb, in units of ; is the lateral force coefficient; For superelevation, use "+" when setting superelevation, and use "-" when setting directional superelevation; The expected speed of each incoming vehicle at the intersection should meet the recommended value when the road capacity is maximum. , and should be less than or equal to the turning speed constrained by the right turn , and at the same time less than or equal to the maximum speed of the roads in each import direction The control speed of the expected speed of each incoming vehicle at the intersection is shown in the following formula (3): （3） 3. The method for forming a continuous flow of small-volume straight-right mixed vehicles at an Internet of Things intersection according to claim 1 is characterized in that: In step S4, the preceding vehicle is a vehicle , the rear vehicle is a vehicle , the parking sight distance calculation process is shown in formula (7): （7） Where: For vehicles The driving speed is for driver reaction time; is the longitudinal friction coefficient between the road surface and the tire; For a safe distance.

4. The method for forming a continuous flow of small-volume straight-right mixed vehicles at an Internet of Things intersection according to claim 1 is characterized in that: In step S5, when the vehicle Entering the perception pre-control section, the extension of its trajectory is consistent with other vehicles in the control area When the trajectory extension lines of the vehicles intersect or overlap, With vehicle There is a conflict area between the adjacent import directions; the conflict area includes the conflict area between the straight vehicles in the adjacent import directions and the conflict area between the right-turning vehicle and the straight vehicles in the adjacent import directions.

5. The method for forming a continuous flow of small-volume straight-right mixed vehicles at an Internet of Things intersection according to claim 1 is characterized in that: In the step S9, determining the speed control strategy for non-oncoming vehicles includes eliminating conflicts between non-oncoming vehicles, boundary conditions for the vehicle speed control strategy, and determining the vehicle speed control strategy.

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