Control decision-making method for linkage turning of multiple vehicles on road section

Abstract

The invention relates to the technical field of automatic driving vehicle turning, and discloses a control decision-making method for multi-vehicle linkage turning on a road section, which comprises the following steps of: determining environment information around a vehicle and position information of the vehicle through a plurality of vehicle-mounted sensors, and calculating a front vehicle risk parameter and a rear vehicle risk parameter; the turning-around vehicle makes a decision for turning around or not by judging the relative position of the opposite vehicles and the size of the gap between the opposite vehicles in advance, the turning-around vehicle comprises the head vehicle and the vehicles waiting for turning around after the head vehicle, and turning-around operation is carried out. According to the method, the position of the vehicle and the environment information around the vehicle are detected through a plurality of vehicle-mounted sensors, and judgment and control of the turning-around requirement are achieved, so that the problems that in the prior art, the vehicle turning-around driving difficulty is higher, and automatic and intelligent turning-around operation is achieved in the complex road environment are solved; and the safety and convenience of turning around of the vehicle are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of U-turn of autonomous driving vehicles, and in particular to a control decision method for coordinated U-turn of multiple vehicles on a road section. Background Art

[0002] Intersections usually need to meet the needs of going straight and turning left, which account for a large proportion of the total traffic volume. U-turn vehicles are not paid much attention because of their small traffic volume and small proportion of the total traffic volume. However, U-turn traffic flow on urban roads is an important bottleneck in road traffic operation and one of the important problems facing urban road traffic management.

[0003] Autonomous driving vehicles are one of the development trends of intelligent vehicles in the future. The research on autonomous driving vehicles will also promote the development of intelligent transportation and smart cities, which is of great significance. U-turn is an operation that drivers often need to perform in urban road environments. Autonomous driving vehicles also need to complete the vehicle U-turn function. Generally speaking, a vehicle U-turn takes more time than a vehicle turning left, right, or going straight, and it is more difficult to drive. Especially for complex and changeable real-life scenarios, the U-turn problem of autonomous driving vehicles has always been a technical difficulty. However, existing research on U-turn traffic focuses on the remote U-turn position, or the delay caused by U-turn and the form of U-turn, as well as U-turn conflict measurement indicators. There are few scenarios of multi-vehicle linkage U-turns, and there is little research on the risks between multi-vehicle linkage U-turn vehicles and U-turn vehicle decisions. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the present invention provides a control decision method for multi-vehicle coordinated U-turn on a road section, which has the advantages of ensuring the safety and smooth completion of the U-turn operation, and solves the above-mentioned technical problems.

[0006] (II) Technical solution

[0007] To achieve the above object, the present invention provides the following technical solution: a control decision method for multi-vehicle coordinated U-turn on a road section, comprising the following steps:

[0008] Step 1: Determine the environmental information around the vehicle and the location information of the vehicle through multiple on-board sensors;

[0009] Step 2, calculate the risk parameter of the leading vehicle and the risk parameter of the trailing vehicle, wherein the risk parameter of the leading vehicle is the conflict between the vehicle in the opposite lane and the U-turning vehicle when the U-turning vehicle turns to the opposite lane, and the risk parameter of the trailing vehicle is the conflict between the vehicle in the opposite lane and the current U-turning vehicle;

[0010] Step 3: The U-turn vehicle makes a decision on whether to turn by judging the relative position of the oncoming vehicle and the gap between the oncoming vehicles in advance. The U-turn vehicle includes the lead vehicle and the vehicles waiting to turn behind the lead vehicle.

[0011] Step 4: Make a U-turn based on the decision made in Step 3.

[0012] As a preferred technical solution of the present invention, the risk parameter of the preceding vehicle in Step 2 is expressed by the post-intrusion time, and the specific expression is as follows:

[0013] PET=t2-t1

[0014] Among them, PET represents the post-intrusion time, t2 represents the time when the front vehicle in the opposite lane passes the conflict point, and t1 represents the time when the U-turn vehicle reaches the conflict point.

[0015] As a preferred technical solution of the present invention, the following vehicle risk parameter includes the longitudinal distance s between the rear end of the current U-turn vehicle and the head of the following vehicle in the opposite lane after the U-turn. x , its specific expression is as follows:

[0016] s x =s0-s1-Lcosθ+r

[0017] Where s0 represents the longitudinal distance traveled by the U-turning vehicle, s1 represents the longitudinal distance traveled by the following vehicle, L represents the length of the U-turning vehicle, and r represents the redundant distance;

[0018] It also includes the minimum distance for the U-turn vehicle to reach the U-turn completion point. The specific expression is as follows:

[0019]

[0020] Among them, s min represents the minimum distance for the U-turn vehicle to reach the U-turn completion point, s(t0) represents the distance traveled by the U-turn vehicle at time t0, a0(τ) represents the acceleration of the U-turn vehicle at time τ, a1(τ) represents the acceleration of the rear vehicle in the opposite lane at time τ, v0 is the speed of the U-turn vehicle at time t0, v1 is the speed of the rear vehicle in the opposite lane at time t0, t0 represents the time when the U-turn vehicle enters the U-turn area, It represents the acceleration change of the U-turn vehicle and the distance difference between the oncoming vehicle, where τ represents the moment of acceleration change and t represents the moment when the U-turn is completed.

[0021] As a preferred technical solution of the present invention, the specific process of the vehicle U-turn in Step 3 is that the U-turn vehicle A1 is the lead vehicle and is in lane 1, vehicles B1 and B2 are in the opposite lane 2, vehicles C1 and C2 are in the opposite lane 3, lane 1 is adjacent to the opposite lane 2, and the U-turn vehicle A1 starts from lane 1, turns around along the opposite lane 2, and finally arrives at the opposite lane 3, wherein the U-turn vehicle A1 starts from lane 1 and turns around along the opposite lane 2, including the following situations:

[0022] Case 1: U-turn vehicle A1 is behind vehicles B1 and B2 in the opposite lane 2 in the driving direction during the U-turn process. At this time, the vehicles waiting to U-turn behind U-turn vehicle A1 make a new decision on whether to U-turn;

[0023] Case 2: U-turn vehicle A1 is in front of vehicles B1 and B2 in the opposite lane 2 in the driving direction during the U-turn process. At this time, U-turn vehicle A1 blocks the traffic flow, and the vehicles waiting to U-turn behind U-turn vehicle A1 directly make a U-turn;

[0024] Scenario 3: U-turn vehicle A1 merges into vehicles B1 and B2 in the opposite lane 2. At this time, the vehicles waiting to U-turn behind U-turn vehicle A1 give way to vehicles B1 and B2.

[0025] The U-turn vehicle A1 arrives at the oncoming lane 3 in the following situations:

[0026] Scenario 4: U-turn vehicle A1 merges into vehicles C1 and C2 in the opposite lane;

[0027] Scenario 5: U-turn vehicle A1 merges into the oncoming lane before vehicles C1 and C2;

[0028] Scenario 6: U-turn vehicle A1 merges into vehicles C1 and C2 in the opposite lane.

[0029] As a preferred technical solution of the present invention, the constraint condition for the occurrence of the fourth situation is: the distance from the vehicle B2, C2 to the turning position of the U-turning vehicle A1 is less than the distance from the position where the U-turning vehicle A1 is ready to turn to the turning position, and the speed of the U-turning vehicle A1 is lower than the speed of the vehicles B2, C2. The specific expression is as follows:

[0030]

[0031] Among them, L B2 (t) represents the distance from the vehicle B2 in the opposite lane to the turning position of the U-turn vehicle A1, L C2 (t) represents the distance from the vehicle C2 in the opposite lane to the turning position of the U-turn vehicle A1, L B2 (t0) represents the distance from the vehicle B2 in the opposite lane to the U-turn position at time t0, represents the distance traveled by vehicle B2 from t0 to time t, represents the distance traveled by vehicle C2 from time t0 to time t, t0 represents the time when the U-turn vehicle enters the U-turn area, s min represents the minimum distance for a U-turn vehicle to reach the U-turn completion point, v A1 (t end ) indicates t end The speed of vehicle A1 at this moment, v B2 (t end ) indicates t end The speed of vehicle B2 at this moment, v C2 (t end ) indicates t end The speed of vehicle C2 at this moment.

[0032] As a preferred technical solution of the present invention, the constraint conditions for the occurrence of the fifth situation are: the distance between the vehicles B1 and C1 and the turning position of the U-turning vehicle A1 is greater than the distance between the position where the U-turning vehicle A1 is preparing to turn and the turning position, and the speed of the U-turning vehicle A1 is higher than the speed of the vehicles B1 and C1 on the opposite lane. The specific expression is as follows:

[0033]

[0034] Among them, L B1 (t) represents the distance from the vehicle B1 in the opposite lane to the turning position of the U-turn vehicle A1, L C1 (t) represents the distance from the vehicle C1 in the opposite lane to the turning position of the U-turn vehicle A1, L B1 (t0) represents the distance from the vehicle B1 in the opposite lane to the U-turn position at time t0, represents the distance traveled by vehicle B1 from t0 to time t, represents the distance traveled by vehicle C1 from time t0 to time t, t0 represents the time when the U-turn vehicle enters the U-turn area, s min represents the minimum distance for a U-turn vehicle to reach the U-turn completion point, v A1 (t end ) indicates t end The speed of vehicle A1 at this moment, v B1 (t end ) indicates t end The speed of vehicle B1 at this moment, v C1 (t end ) indicates t end The speed of vehicle C1 at the moment.

[0035] As a preferred technical solution of the present invention, the constraint conditions for the occurrence of the sixth situation are as follows: the distance between the vehicle B2 and the turning position of the U-turning vehicle A1 is greater than the minimum distance for the U-turning vehicle to reach the U-turn completion point, and the vehicle B1 has passed the U-turning position of the U-turning vehicle A1, and when the U-turn is completed, the distance between the vehicle C2 and the U-turning position of the U-turning vehicle A1 is greater than the set distance, and the vehicle C1 has passed the U-turning position of the U-turning vehicle A1. The specific expression is as follows:

[0036] L B2 (t end )>s min

[0037] When vehicle C1 reaches the U-turn point s2, in order to prevent a collision in lane 2, vehicle B1 in the opposite lane should be allowed to go first to ensure the safety of the U-turn operation.

[0038] L B1 (t end )>s2

[0039]

[0040] Among them, L B1 (t end ) indicates t end The distance between vehicle B1 and the turning position of vehicle A1 at the moment, s 始 Indicates the position where vehicle A1 starts to turn around. It means that vehicle A1 goes from t0 to t end Distance of U-turn, L A1 (t0) represents the distance between the U-turn vehicle and the U-turn point, It indicates that vehicle C1 arrives at the U-turn point s2.

[0041] Similarly,

[0042] L C1 (t end )>s2

[0043]

[0044] When car A1 turns to lane 3, its speed is often lower than other cars in the lane. In order to avoid collision with other vehicles when turning, the distance L between vehicle C2 and the turning point is set to 0. C2 (t end ) must meet the following requirements:

[0045]

[0046] Among them, L B2 (tend ) indicates t end The distance between vehicle B2 and the turning position of vehicle A1 at the moment, s min Indicates the minimum distance for a U-turn vehicle to reach the U-turn completion point, L C2 (t end ) indicates t end The distance between vehicle C2 and the turning position of vehicle A1 at the moment, v C and v A They represent the speeds of vehicles in lane 1 and lane 3 when they are running steadily, and a represents the acceleration of the oncoming vehicle.

[0047] Compared with the prior art, the present invention provides a control decision method for multi-vehicle coordinated U-turn on a road section, which has the following beneficial effects:

[0048] The present invention detects the position of the vehicle and the environmental information around the vehicle through multiple vehicle-mounted sensors, and realizes the judgment and control of the need for U-turn to solve the problem that the vehicle U-turn driving is more difficult in the prior art, and realizes automated and intelligent U-turn operation in a complex road environment, thereby ensuring the safety and convenience of the vehicle U-turn. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of the process of the present invention;

[0050] Figure 2 It is a decision diagram of the finite state machine of the present invention;

[0051] Figure 3 This is a schematic diagram of the risk of a rear vehicle according to the present invention;

[0052] Figure 4 This is a schematic diagram of the risk of the preceding vehicle of the present invention;

[0053] Figure 5 This is a schematic diagram of the U-turn area setting of the present invention. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] See also Figure 1-Figure 5 , a control decision method for a multi-vehicle coordinated U-turn on a road section, comprising the following steps:

[0056] Step 1. Determine the environmental information around the vehicle and the location of the vehicle through multiple on-board sensors. On-board sensors include laser radar, cameras, ultrasonic sensors, etc., which are used to obtain information about the surrounding environment. On-board sensors can obtain detailed information about the surrounding environment through a variety of sensors. For example, laser radar can obtain information such as lane lines and traffic lights; cameras can obtain information such as lane lines, traffic lights, obstacles, traffic signs, etc.; ultrasonic waves can obtain obstacle information; GPS locators can obtain vehicle location information, etc.

[0057] Step 2. Calculate the risk parameters of the leading vehicle and the trailing vehicle. The risk parameter of the leading vehicle refers to the conflict between the vehicle in the opposite lane and the U-turning vehicle (main vehicle) when the U-turning vehicle turns to the opposite lane. The risk parameter of the trailing vehicle refers to the conflict between the vehicle in the opposite lane and the current U-turning vehicle.

[0058] In Step 2, the risk parameter of the preceding vehicle is expressed by the post-intrusion time. The specific expression is as follows:

[0059] PET=t2-t1

[0060] Among them, PET represents the post-intrusion time, t2 represents the time when the front vehicle in the opposite lane passes the conflict point, and t1 represents the time when the U-turn vehicle reaches the conflict point.

[0061] The rear vehicle risk parameter includes the longitudinal distance s between the rear end of the current U-turn vehicle and the head of the rear vehicle in the opposite lane after the U-turn. x , its specific expression is as follows:

[0062] s x =s0-s1-Lcosθ+r

[0063] Where s0 represents the longitudinal distance traveled by the U-turning vehicle, s1 represents the longitudinal distance traveled by the following vehicle, L represents the length of the U-turning vehicle, and r represents the redundant distance;

[0064] It also includes the minimum distance for the U-turn vehicle to reach the U-turn completion point. The specific expression is as follows:

[0065]

[0066] Among them, s min represents the minimum distance for the U-turn vehicle to reach the U-turn completion point, s(t0) represents the distance traveled by the U-turn vehicle at time t0, a0(τ) represents the acceleration of the U-turn vehicle at time τ, a1(τ) represents the acceleration of the rear vehicle in the opposite lane at time τ, v0 is the speed of the U-turn vehicle at time t0, v1 is the speed of the rear vehicle in the opposite lane at time t0, t0 represents the time when the U-turn vehicle enters the U-turn area, It represents the acceleration change of the U-turn vehicle and the distance difference between the oncoming vehicle, where τ represents the moment of acceleration change and t represents the moment when the U-turn is completed.

[0067] Step 3: The U-turn vehicle makes a decision on whether to turn by judging the relative position of the oncoming vehicle and the gap between the oncoming vehicles in advance. The U-turn vehicle includes the lead vehicle and the vehicles waiting to turn behind the lead vehicle.

[0068] Take a two-way four-lane section with a U-turn as an example. The lane from south to north is the main lane, and the lane from north to south is the opposite lane;

[0069] The specific process of the vehicle U-turn in Step 3 is that the U-turn vehicle A1 is the lead vehicle and is in lane 1, vehicles B1 and B2 are in the opposite lane 2, and vehicles C1 and C2 are in the opposite lane 3. Lane 1 is adjacent to the opposite lane 2. The U-turn vehicle A1 starts from lane 1, turns around along the opposite lane 2, and finally arrives at the opposite lane 3. Among them, the U-turn vehicle A1 starts from lane 1 and turns around along the opposite lane 2, including the following situations:

[0070] Case 1: The U-turn vehicle A1 is behind the vehicles B1 and B2 in the opposite lane 2 in the driving direction during the U-turn process. At this time, the vehicles waiting to U-turn behind the U-turn vehicle A1 make a new decision on whether to U-turn.

[0071] Case 2: U-turn vehicle A1 is in front of vehicles B1 and B2 in the opposite lane 2 in the driving direction during the U-turn process. At this time, U-turn vehicle A1 blocks the traffic flow, and the vehicles waiting to U-turn behind U-turn vehicle A1 directly make a U-turn.

[0072] Situation 3: The U-turn vehicle A1 merges into the vehicles B1 and B2 in the opposite lane 2. At this time, the vehicles waiting to U-turn behind the U-turn vehicle A1 give way to the vehicles B1 and B2.

[0073] When the vehicle makes a U-turn, the U-turn vehicle A1 needs to calculate whether there is a safe gap between the vehicles B1, B2, C1 and C2 on the opposite lane when making a U-turn, so as to determine whether a safe U-turn operation can be achieved. Here, the initial position of the U-turn vehicle A1 is recorded as S1, the position to be turned is recorded as s2, the initial position of the opposite lane B1 and C1 is S3, and the initial position of B2 and C2 is S4. If there is a safe gap between vehicles B1 and B2 on lane 2 and vehicles C1 and C2 on lane 3, vehicle A1 can provide a basis for the decision of whether to make a U-turn by judging the size of the gap in advance.

[0074] The initial time when vehicle A1 is about to enter the U-turn area is t0, and the distances between the vehicles in the opposite lane and the U-turn point s2 are L B1 (t0), L B1(t0), L C1 (t0), L C1 (t0), the distance between the U-turn vehicle and the U-turn point is L A1 (t0), t end is the end time of the U-turn, and the duration of the entire U-turn process is t∈[t0, t end ].

[0075] The U-turn vehicle A1 arrives at the oncoming lane 3 in the following situations:

[0076] Scenario 4: U-turn vehicle A1 merges into vehicles C1 and C2 in the opposite lane;

[0077] The constraint conditions for the occurrence of situation 4 are: the distance from vehicles B2 and C2 to the turning position of vehicle A1 is less than the distance from the position where vehicle A1 is preparing to turn to the turning position, and the speed of vehicle A1 is lower than that of vehicles B2 and C2. The specific expression is as follows:

[0078]

[0079] Among them, L B2 (t) represents the distance from the vehicle B2 in the opposite lane to the turning position of the U-turn vehicle A1, L C2 (t) represents the distance from the vehicle C2 in the opposite lane to the turning position of the U-turn vehicle A1, L B2 (t0) represents the distance from the vehicle B2 in the opposite lane to the U-turn position at time t0, represents the distance traveled by vehicle B2 from t0 to time t, represents the distance traveled by vehicle C2 from time t0 to time t, t0 represents the time when the U-turn vehicle enters the U-turn area, s min represents the minimum distance for a U-turn vehicle to reach the U-turn completion point, v A1 (t end ) indicates t end The speed of vehicle A1 at this moment, v B2 (t end ) indicates t end The speed of vehicle B2 at this moment, v C2 (t end ) indicates t end The speed of vehicle C2 at this moment.

[0080] If both of the above conditions are met, the U-turn vehicle A1 can turn around and merge into the oncoming vehicles C1 and C2 and complete the U-turn safely.

[0081] Scenario 5: U-turn vehicle A1 merges in front of vehicles C1 and C2 in the opposite lane.

[0082] The specific constraint conditions for the occurrence of situation 5 are: the distance between vehicles B1 and C1 and the turning position of the U-turn vehicle A1 is greater than the distance between the position where the U-turn vehicle A1 is preparing to turn and the turning position, and the speed of the U-turn vehicle A1 is higher than the speed of vehicles B1 and C1 in the opposite lane. The specific expression is as follows:

[0083]

[0084] Among them, L B1 (t) represents the distance from the vehicle B1 in the opposite lane to the turning position of the U-turn vehicle A1, L C1 (t) represents the distance from the vehicle C1 in the opposite lane to the turning position of the U-turn vehicle A1, L B1 (t0) represents the distance from the vehicle B1 in the opposite lane to the U-turn position at time t0, represents the distance traveled by vehicle B1 from t0 to time t, represents the distance traveled by vehicle C1 from time t0 to time t, t0 represents the time when the U-turn vehicle enters the U-turn area, s min represents the minimum distance for a U-turn vehicle to reach the U-turn completion point, v A1 (t end ) indicates t end The speed of vehicle A1 at this moment, v B1 (t end ) indicates t end The speed of vehicle B1 at this moment, v C1 (t end ) indicates t end The speed of vehicle C1 at the moment.

[0085] If both of the above conditions are met, the U-turn vehicle A1 can turn around and merge in front of the oncoming vehicles C1 and C2 and complete the U-turn safely.

[0086] Scenario 6: U-turn vehicle A1 merges into vehicles C1 and C2 in the opposite lane.

[0087] The specific constraint conditions for the occurrence of situation six are: the distance between vehicle B2 and the turning position of U-turn vehicle A1 is greater than the minimum distance for the U-turn vehicle to reach the U-turn completion point, and vehicle B1 has passed the U-turn position of U-turn vehicle A1, and when the U-turn is completed, the distance between vehicle C2 and the U-turn position of U-turn vehicle A1 is greater than the set distance, and vehicle C1 has passed the U-turn position of U-turn vehicle A1. The specific expression is as follows:

[0088] L B2 (t end )>s min

[0089] When vehicle C1 reaches the U-turn point s2, in order to prevent a collision in lane 2, vehicle B1 in the opposite lane should be allowed to go first to ensure the safety of the U-turn operation.

[0090] L B1 (t end )>s2

[0091]

[0092] Among them, L B1 (t end ) indicates t end The distance between vehicle B1 and the turning position of vehicle A1 at the moment, s 始 Indicates the position where vehicle A1 starts to turn around. It means that vehicle A1 goes from t0 to t end Distance of U-turn, L A1 (t0) represents the distance between the U-turn vehicle and the U-turn point, It indicates that vehicle C1 arrives at the U-turn point s2.

[0093] Similarly,

[0094] L C1 (t end )>s2

[0095]

[0096] When car A1 turns to lane 3, its speed is often lower than other cars in the lane. In order to avoid collision with other vehicles when turning, the distance L between vehicle C2 and the turning point is set to 0. C2 (t end ) must meet the following requirements:

[0097]

[0098] Among them, L B2 (t end ) indicates t end The distance between vehicle B2 and the turning position of vehicle A1 at the moment, s min Indicates the minimum distance for a U-turn vehicle to reach the U-turn completion point, L C2 (t end ) indicates t end The distance between vehicle C2 and the turning position of vehicle A1 at the moment, v C and v A They represent the speeds of vehicles in lane 1 and lane 3 when they are running steadily, and a represents the acceleration of the oncoming vehicle.

[0099] When the above four conditions are met, there is a safe gap for inserting vehicles, and A1 can make a safe U-turn.

[0100] Step 4, perform a U-turn according to the decision made in step 3;

[0101] Use the finite state machine model to make decisions; a finite state machine is an abstract mathematical model used to describe the behavior of an object, system, or program; it consists of a set of states, a set of transitions, and a set of actions. Each state represents a specific situation of the system at different points in time, a transition represents the transformation of the system between different states, and an action represents the action performed by the system when the state transitions. Finite state machines can be applied to behavioral decisions that control vehicles; states can be finite, and at any given time, the system can only be in one of these states. In a U-turn scenario, possible states include whether there is a vehicle ahead, whether the U-turn area is occupied, etc.; the transition condition indicates under what conditions the system will transfer to another state in a state; for example, when there is a vehicle ahead, the vehicle may need to wait for the vehicle ahead to pass, and only after the waiting is over can it enter the U-turn area; the behavior indicates the specific action that the system needs to perform in a certain state. For example, when the U-turn area is not occupied, the vehicle can start the U-turn operation.

[0102] In the decision model of a U-turn vehicle, a finite state machine can be used to describe the decisions that the U-turn vehicle should take in different states to achieve a safe U-turn and avoid conflicts with oncoming vehicles.

[0103] In the U-turn vehicle decision model of the present invention, the state machine includes the following states:

[0104] (1) Straight-moving state: The U-turn vehicle is traveling on a straight road and does not need to turn.

[0105] (2) U-turn preparation state: The U-turn vehicle approaches the intersection and prepares to turn.

[0106] (3) Waiting state: When a U-turn vehicle arrives at the intersection, it needs to wait for the oncoming vehicle to pass.

[0107] (4) U-turn status: After the oncoming vehicle passes, the U-turn vehicle starts to turn around.

[0108] (5) Completed U-turn status: The U-turn vehicle completes the U-turn and leaves the intersection.

[0109] In each state, the U-turn vehicle needs to make corresponding decisions based on the current scene and information. For example, in the waiting state, if the oncoming vehicle has passed, the U-turn vehicle can enter the U-turn state; if the vehicle in front has not passed, it needs to continue waiting.

[0110] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A control decision method for multi-vehicle coordinated U-turn on a road section, characterized by: The following steps are involved: Step 1: Determine the environmental information around the vehicle and the location information of the vehicle through multiple on-board sensors; Step 2, calculate the risk parameter of the leading vehicle and the risk parameter of the trailing vehicle, wherein the risk parameter of the leading vehicle is the conflict between the vehicle in the opposite lane and the U-turning vehicle when the U-turning vehicle turns to the opposite lane, and the risk parameter of the trailing vehicle is the conflict between the vehicle in the opposite lane and the current U-turning vehicle; Step 3: The U-turn vehicle makes a decision on whether to turn by judging the relative position of the oncoming vehicle and the gap between the oncoming vehicles in advance. The U-turn vehicle includes the lead vehicle and the vehicles waiting to turn behind the lead vehicle. Step 4: Make a U-turn based on the decision made in Step 3.

2. The control decision method for multi-vehicle coordinated U-turn on a road section according to claim 1 is characterized by: The risk parameter of the preceding vehicle in Step 2 is expressed by the post-intrusion time, and the specific expression is as follows: PET=t2-t1 Among them, PET represents the post-intrusion time, t2 represents the time when the front vehicle in the opposite lane passes the conflict point, and t1 represents the time when the U-turn vehicle arrives at the conflict point.

3. The control decision method for multi-vehicle coordinated U-turn on a road section according to claim 2 is characterized in that: The following vehicle risk parameter includes the longitudinal distance s between the rear end of the current U-turn vehicle and the head of the following vehicle in the opposite lane after the U-turn. x , its specific expression is as follows: s x =s0-s1-Lcosθ+r Where s0 represents the longitudinal distance traveled by the U-turn vehicle, s1 represents the longitudinal distance traveled by the following vehicle, L represents the length of the U-turn vehicle, r represents the redundant distance, θ represents the angle between the driving direction of the U-turn vehicle and the driving direction of the following vehicle in the opposite lane, and cosθ represents the cosine value; It also includes the minimum distance for the U-turn vehicle to reach the U-turn completion point. The specific expression is as follows: Among them, s min represents the minimum distance for the U-turn vehicle to reach the U-turn completion point, s(t0) represents the distance traveled by the U-turn vehicle at time t0, a0(τ) represents the acceleration of the U-turn vehicle at time t, a1(τ) represents the acceleration of the rear vehicle in the opposite lane at time τ, v0 is the speed of the U-turn vehicle at time t0, v1 is the speed of the rear vehicle in the opposite lane at time t0, t0 represents the time when the U-turn vehicle enters the U-turn area, It represents the acceleration change of the U-turn vehicle and the distance difference between the oncoming vehicle, where τ represents the moment of acceleration change and t represents the moment when the U-turn is completed.

4. The control decision method for multi-vehicle coordinated U-turn on a road section according to claim 1, characterized in that: The specific process of the vehicle U-turn in Step 3 is that the U-turn vehicle A1 is the lead vehicle and is in lane 1, vehicles B1 and B2 are in the opposite lane 2, vehicles C1 and C2 are in the opposite lane 3, lane 1 is adjacent to the opposite lane 2, and the U-turn vehicle A1 starts from lane 1, turns around along the opposite lane 2, and finally arrives at the opposite lane 3. The U-turn vehicle A1 starts from lane 1 and turns around along the opposite lane 2, including the following situations: Case 1: U-turn vehicle A1 is behind vehicles B1 and B2 in the opposite lane 2 in the driving direction during the U-turn process. At this time, the vehicles waiting to U-turn behind U-turn vehicle A1 make a new decision on whether to U-turn; Case 2: U-turn vehicle A1 is in front of vehicles B1 and B2 in the opposite lane 2 in the driving direction during the U-turn process. At this time, U-turn vehicle A1 blocks the traffic flow, and the vehicles waiting to U-turn behind U-turn vehicle A1 directly make a U-turn; Scenario 3: U-turn vehicle A1 merges into vehicles B1 and B2 in the opposite lane 2. At this time, the vehicles waiting to U-turn behind U-turn vehicle A1 give way to vehicles B1 and B2. The U-turn vehicle A1 arrives at the oncoming lane 3 in the following situations: Scenario 4: U-turn vehicle A1 merges into vehicles C1 and C2 in the opposite lane; Scenario 5: U-turn vehicle A1 merges into the oncoming lane before vehicles C1 and C2; Scenario 6: U-turn vehicle A1 merges into vehicles C1 and C2 in the opposite lane.

5. The control decision method for multi-vehicle coordinated U-turn on a road section according to claim 4 is characterized in that: The constraint conditions for the occurrence of the fourth situation are: the distance from vehicles B2 and C2 to the turning position of the U-turning vehicle A1 is less than the distance from the position where the U-turning vehicle A1 is preparing to turn to the turning position, and the speed of the U-turning vehicle A1 is lower than the speed of vehicles B2 and C2. The specific expression is as follows: Among them, L B2 (t) represents the distance from the vehicle B2 in the opposite lane to the turning position of the U-turn vehicle A1, L C2 (t) represents the distance from the vehicle C2 in the opposite lane to the turning position of the U-turn vehicle A1, L B2 (t0) represents the distance from the vehicle B2 in the opposite lane to the U-turn position at time t0, represents the distance traveled by vehicle B2 from t0 to time t, represents the distance traveled by vehicle C2 from time t0 to time t, t0 represents the time when the U-turn vehicle enters the U-turn area, s min represents the minimum distance for a U-turn vehicle to reach the U-turn completion point, v A1 (t end ) indicates t end The speed of vehicle A1 at this moment, v B2 (t end ) indicates t end The speed of vehicle B2 at this moment, ν C2 (t end ) indicates t end The speed of vehicle C2 at this moment.

6. The control decision method for multi-vehicle coordinated U-turn on a road section according to claim 4, characterized in that: The constraint conditions for the occurrence of the fifth situation are as follows: the distance from the vehicle B1 and C1 to the turning position of the U-turn vehicle A1 is greater than the distance from the position where the U-turn vehicle A1 is preparing to turn to the turning position, and the speed of the U-turn vehicle A1 is higher than the speed of the vehicles B1 and C1 in the opposite lane. The specific expression is as follows: Among them, L B1 (t) represents the distance from the vehicle B1 in the opposite lane to the turning position of the U-turn vehicle A1, L C1 (t) represents the distance from the vehicle C1 in the opposite lane to the turning position of the U-turn vehicle A1, L B1 ( t0 ) represents the distance from the vehicle B1 in the opposite lane to the U-turn position at time t0, represents the distance traveled by vehicle B1 from t0 to time t, represents the distance traveled by vehicle C1 from time t0 to time t, t0 represents the time when the U-turn vehicle enters the U-turn area, S min represents the minimum distance for a U-turn vehicle to reach the U-turn completion point, v A1 (t end ) indicates t end The speed of vehicle A1 at this moment, v B1 (t end ) indicates t end The speed of vehicle B1 at this moment, v C1 (t end ) indicates t end The speed of vehicle C1 at the moment.

7. The control decision method for multi-vehicle coordinated U-turn on a road section according to claim 4, characterized in that: The constraint conditions for the occurrence of the sixth situation are as follows: the distance between vehicle B2 and the turning position of the U-turning vehicle A1 is greater than the minimum distance for the U-turning vehicle to reach the U-turn completion point, and vehicle B1 has passed the turning position of the U-turning vehicle A1, and when the U-turn is completed, the distance between vehicle C2 and the turning position of the U-turning vehicle A1 is greater than the set distance, and vehicle C1 has passed the turning position of the U-turning vehicle A1. The specific expression is as follows: L B2 (t end )>s minm L B1 (t end )>s2 Among them, L B1 (t end ) indicates t end The distance between vehicle B1 and the turning position of vehicle A1 at the moment, s 始 Indicates the position where vehicle A1 starts to turn around. It means that vehicle A1 goes from t0 to t end Distance of U-turn, L A1 (t0) represents the distance between the U-turn vehicle and the U-turn point, It means that vehicle C1 arrives at the U-turn point s2; L C1 (t end )>s2 When the U-turn is completed, the distance L between vehicle C2 and the turning point is C2 (t end ) must meet the following requirements: Among them, L B2 (t end ) indicates t end The distance between vehicle B2 and the turning position of vehicle A1 at the moment, s min Indicates the minimum distance for a U-turn vehicle to reach the U-turn completion point, L C2 (t end ) indicates t end The distance between vehicle C2 and the turning position of vehicle A1 at the moment, v C and v A They represent the speeds of vehicles in lane 1 and lane 3 when they are running steadily, and a represents the acceleration of the oncoming vehicle.

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