Intelligent network connection automobile special lane cooperative convergence control method based on virtual automobile relaxation

Abstract

The invention discloses an intelligent network connection automobile special lane cooperative convergence control method based on virtual vehicle relaxation. The method comprises the following steps: step 1, executing step 2 when a lane changing decision condition is satisfied; 2, judging whether a queue jumping condition is met or not based on a gap selection model, and if yes, executing the step 3; 3, the intelligent networked vehicle on the mixed lane tries to change the lane to a CAV special lane, a virtual vehicle is inserted into two transversely adjacent workshops in the CAV queue, the acceleration and the vehicle distance of the CAV queue are dynamically adjusted based on a virtual vehicle relaxation model, and the step 4 is executed until the overall speed of the vehicle queue is balanced; and step 4, the intelligent networked vehicle to be subjected to lane change is changed into the intelligent networked vehicle queue of the CAV special lane. According to the method, the vehicle team disturbance phenomenon can be well reduced, so that the operation efficiency and safety of the CAV queue on the CAV special lane are ensured.

Description

Technical Field

[0001] The present invention relates to the field of autonomous driving formation control methods, and in particular to a collaborative merging control method for intelligent connected vehicles in dedicated lanes based on virtual vehicle relaxation. Background Art

[0002] In recent years, the field of autonomous driving has been developing rapidly. With the replacement of intelligent connected vehicle (CAV) technology, before achieving fully autonomous driving in the future, the phenomenon of human-machine mixed driving will first appear on the road, that is, mixed driving of human-driven vehicles (HDV) and CAV.

[0003] Because mixed lanes accommodate not only CAVs but also a large number of HDVs, CAV platooning is difficult in these lanes. The current solution is to establish dedicated CAV lanes for CAVs, allowing only CAVs to operate in these lanes, thereby ensuring a complete platoon. Within these lanes, each CAV maintains a predetermined balanced and stable acceleration, forming a platoon with equal distances between adjacent vehicles.

[0004] When a CAV in a mixed lane needs to change lanes to a dedicated CAV lane, it significantly disrupts the queue of CAVs in the dedicated CAV lane, leading to traffic safety issues in the dedicated CAV lane. Therefore, it is necessary to provide a coordinated merging control strategy for CAVs changing from a mixed lane to a dedicated CAV lane to minimize disruption to traffic flow in the dedicated CAV lane. Summary of the Invention

[0005] The present invention provides a collaborative merging control method for intelligent connected vehicle dedicated lanes based on virtual vehicle relaxation, so as to solve the problem in the prior art that when a CAV changes lanes from a mixed lane to a CAV dedicated lane, the traffic flow in the CAV dedicated lane is significantly disturbed.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A collaborative merging control method for intelligent connected vehicles (ICVs) in dedicated lanes based on virtual vehicle slack is used to control an ICV to merge from a mixed lane into a CAV-dedicated lane. The process is as follows:

[0008] Step 1: Determine whether the lane change decision conditions are met based on the lane change decision conditions. If so, proceed to step 2.

[0009] Step 2: Based on the gap selection model, determine whether the gap between two adjacent intelligent connected vehicles in the CAV dedicated lane and the intelligent connected vehicle to be changed meets the queue-jumping condition. If so, execute step 3.

[0010] Step 3: Based on the virtual vehicle relaxation model, when an intelligent connected vehicle in a mixed lane attempts to change lanes to the CAV lane, a virtual vehicle is inserted between the two vehicles in the CAV platoon that are laterally adjacent to it. The acceleration and inter-vehicle spacing of the CAV platoon are dynamically adjusted based on the virtual vehicle relaxation model until the overall platoon speed reaches equilibrium. At this point, step 4 is executed.

[0011] Step 4: The intelligent connected vehicle to be changed lanes changes lanes to between two adjacent intelligent connected vehicles in the intelligent connected vehicle queue of the CAV dedicated lane, completing the process of merging the intelligent connected vehicle to be changed lanes into the intelligent connected vehicle queue of the CAV dedicated lane.

[0012] Furthermore, in step 1, the lane change decision conditions are as follows:

[0013] Condition (a): The speed difference between the intelligent connected vehicle to be changed and the speed of the one of the two adjacent intelligent connected vehicles located behind the intelligent connected vehicle to be changed in the CAV lane is greater than 2 m / s, and the speed difference between the intelligent connected vehicle to be changed and the one behind is less than or equal to 7 m / s.

[0014] Condition (b): The number of vehicles behind the ICV in the CAV lane is less than or equal to 5;

[0015] When both conditions (a) and (b) are met, it is determined that the lane change condition is met.

[0016] Furthermore, in step 2, the gap selection model is shown in the following formula:

[0017] x i ≤x CAV ≤x i-1 -l

[0018] Where: x CAV Indicates the position of the front bumper of the smart connected car to be changed lanes; x i Indicates the front bumper position of the rear-end of the two connected vehicles adjacent to the vehicle to be changed in the CAV lane; x i-1 represents the rear bumper position of the front of the two connected vehicles in the CAV lane; l represents the length of the connected vehicle in the lane to be changed;

[0019] When the above gap selection model formula is satisfied, it is determined that the gap between two intelligent connected vehicles adjacent to the intelligent connected vehicle to be changed lanes in the CAV dedicated lane meets the queue-jumping condition.

[0020] Furthermore, in step 3, the virtual car relaxation model is shown in the following formula:

[0021]

[0022] Among them: a n (t) is the acceleration of the nth intelligent connected vehicle; A is the maximum acceleration of the intelligent connected vehicle; v n (t) is the speed of the nth intelligent connected following vehicle at time t; v f is the expected speed of the intelligent connected vehicle fleet; c is the acceleration index; s is the expected safety distance; x n-1 (t) is the position of the n-1th intelligent connected following vehicle at time t; x n (t) is the position of the nth intelligent connected vehicle at time t; l is the length of the intelligent connected vehicle; s0 is the parking safety distance; T safe is the safety time interval; v n-1 (t) is the speed of the n-1th intelligent connected following vehicle at time t; b is the maximum braking deceleration of the vehicle.

[0023] After inserting the virtual vehicle, the vehicle spacing and acceleration of each vehicle in the intelligent connected vehicle fleet on the CAV dedicated lane at time t are calculated based on the above virtual vehicle relaxation model formula. The speed of the intelligent connected vehicle fleet is dynamically adjusted according to the calculation results until the overall speed of the fleet reaches equilibrium.

[0024] Furthermore, when the intelligent connected vehicle to be changed lanes in step 4 changes lanes, a minimum safety distance between the intelligent connected vehicle to be changed lanes and the rear one of the two adjacent intelligent connected vehicles in the intelligent connected vehicle queue is controlled to avoid collision with the rear one.

[0025] Furthermore, the minimum safety distance D min The control formula is shown as follows:

[0026] D min ≥D FV -D CAV +l+W sinθ

[0027] Where: D FV The distance traveled by the rearmost of the two connected vehicles in the CAV lane within the lane-changing time.

[0028] D CAV is the distance traveled by the smart connected vehicle to be changed within the lane change time;

[0029] l is the length of the intelligent connected vehicle to be changed lanes;

[0030] W is the width of the intelligent connected vehicle to be changed lanes;

[0031] θ is the angle between the intelligent connected vehicle to be changed and the horizontal line when changing lanes.

[0032] The collaborative control method of the present invention can mitigate the impact of disturbances to the vehicle queue in the CAV-dedicated lane caused by a CAV waiting to change lanes and merging into it. Specifically, the collaborative deceleration strategy of the present invention preemptively decelerates the vehicles in front and behind the CAV in the CAV-dedicated lane. This prevents a sudden deceleration of traffic in the CAV-dedicated lane when the intelligent connected vehicle waiting to change lanes enters, thus reducing safety hazards.

[0033] In the centralized virtual vehicle relaxation strategy of this invention, when a lane-changing intelligent connected vehicle requests entry, vehicles in front and behind the CAV lane do not need to coordinate deceleration. Instead, the distance between the vehicles in front and behind the CAV lane entry point is directly adjusted. This virtual vehicle relaxation strategy utilizes the ACC linear following model to simulate vehicle following behavior. Based on the distance and speed errors between the two adjacent vehicles in the CAV lane, the acceleration of the vehicles in the CAV lane is adjusted, thereby adjusting the speed and distance between the vehicles in the CAV lane.

[0034] The CAV to be changed enters the CAV platoon in the CAV lane at the average speed of the vehicles in front and behind it, and at the middle position. After the CAV to be changed enters, all vehicles in the CAV lane continue to follow the ACC model, and the platoon eventually reaches a stable state.

[0035] The virtual vehicle relaxation strategy proposed in the present invention can effectively reduce the disturbance of the platoon, so as to ensure the high efficiency and safety of the CAV platoon operation on the CAV dedicated lane. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a flow chart of a method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The present invention will be further described below with reference to the accompanying drawings and examples.

[0038] like Figure 1 As shown, this embodiment discloses a method for controlling a coordinated merging control of a dedicated lane for intelligent connected vehicles based on virtual vehicle slack, which is used to control an intelligent connected vehicle (hereinafter referred to as CAV) to change lanes from a mixed lane to a dedicated CAV lane. The process is as follows:

[0039] Step 1: When the speed of the CAV queue in the CAV-dedicated lane is faster than the speed of the traffic flow in the mixed lane where the CAV to be changed is located, the CAV to be changed has a lane-changing intention. At this time, it is determined whether the lane-changing decision conditions are met.

[0040] The lane change decision conditions are set based on the speed difference between the CAV to be changed and the CAV queue in the CAV dedicated lane, as well as the number of following vehicles in the CAV queue in the CAV dedicated lane behind the CAV to be changed. In this embodiment, the lane change decision conditions are specifically:

[0041] Condition (a), the speed of the CAV to be changed, the CAV behind the CAV to be changed in the CAV dedicated lane i The speed difference between the two vehicles is greater than 2m / s, and the speed of the CAV to be changed is the same as that of the CAV behind it. i The speed difference between the vehicles is less than or equal to 7m / s.

[0042] Condition (b): The number of vehicles behind the CAV to be changed in the CAV dedicated lane is less than or equal to 5.

[0043] When both conditions (a) and (b) are met, it is determined that the lane change condition is met, and step 2 is executed.

[0044] When one or both of conditions (a) and (b) are not met, it is determined that the lane change condition is not met, and step 1 is repeated.

[0045] Step 2: Based on the gap selection model, determine whether the gap between two adjacent intelligent connected vehicles in the CAV dedicated lane meets the queue-jumping condition. If so, execute step 3.

[0046] In this embodiment, the gap selection considers the positional relationship between the CAV to be changed and the two adjacent CAVs in the CAV dedicated lane. Since there is a speed difference between the CAV to be changed and the CAV queue in the CAV dedicated lane, if a closer gap is selected, the CAV queue in the CAV dedicated lane needs to slow down significantly to reserve space for the CAV to be changed; if a farther gap is selected, the CAV to be changed will have its lane change request rejected during the waiting time due to the speed change of the CAV queue in the CAV dedicated lane. Therefore, the gap selection model of this embodiment stipulates that the position of the front bumper of the CAV to be changed is located behind the CAV in the CAV queue in the CAV dedicated lane. i The front bumper and the CAV located in front i-1 The gap selection model is as follows:

[0047] x i ≤x CAV ≤x i-1 -l

[0048] Where: x CAV Indicates the position of the front bumper of the CAV to be changed lanes; x i Indicates the two intelligent connected vehicles (CAVs) adjacent to the CAV to be replaced in the CAV dedicated lane. i 、CAV i-1 The CAV at the rear i Front bumper position; x i-1 Indicates the two intelligent connected vehicles (CAVs) adjacent to the CAV to be replaced in the CAV dedicated lane. i 、CAV i-1 The CAV in the front i-1 The rear bumper position of the vehicle; l represents the body length of the CAV to be changed lanes.

[0049] When the above gap selection model formula is satisfied, the two intelligent connected vehicles (CAVs) adjacent to the CAV to be changed in the CAV dedicated lane are judged. i 、CAV i-1 The gap between them meets the queue-jumping condition.

[0050] Step 3: Based on the virtual vehicle relaxation model, when an intelligent connected vehicle in a mixed lane attempts to change lanes to the CAV lane, a virtual vehicle is inserted between the two laterally adjacent vehicles in the CAV platoon. Based on the virtual vehicle relaxation model, the acceleration and inter-vehicle spacing of the CAV platoon are dynamically adjusted until the overall speed of the platoon reaches equilibrium. Then, step 4 is executed.

[0051] Since the distance between vehicles in the CAV queue in the CAV dedicated lane is small when the speed is balanced, the CAV to be changed cannot directly enter the gap in the CAV queue. Therefore, in this embodiment, the two intelligent connected vehicles CAVs adjacent to the CAV to be changed in the CAV dedicated lane selected in step 2 are i 、CAV i-1 The advantage of the virtual car is that it will not cause collisions between CAVs in the CAV-dedicated lane, and the entire CAV queue will relax due to the insertion of the virtual car, thus reaching a new speed balance.

[0052] In this embodiment, based on the virtual vehicle relaxation model, two intelligent connected vehicles (CAVs) adjacent to the CAV to be replaced in the CAV dedicated lane i 、CAV i-1 A virtual car is inserted into the gap between the two vehicles. The distance between the CAVs in the CAV-dedicated lane changes due to the presence of the virtual car. Under the action of the virtual car relaxation model, the acceleration of the CAVs in the CAV-dedicated lane is adjusted until the CAVs reach speed balance again.

[0053] The virtual vehicle relaxation model primarily considers the distance and speed differences between the front and rear vehicles in a CAV platoon on a dedicated CAV lane, as well as the current speed of the vehicles. When the distance between vehicles changes, the virtual vehicle relaxation model controls the CAV platoon based on vehicle speed, acceleration, and position information until the distance and speed of the CAV platoon approach the desired values.

[0054] In this embodiment, the virtual car relaxation model is shown in the following formula:

[0055]

[0056] Among them: a n (t) is the acceleration of the nth intelligent connected vehicle; A is the maximum acceleration of the intelligent connected vehicle; v n (t) is the speed of the nth intelligent connected following vehicle at time t; v f is the expected speed of the intelligent connected vehicle fleet; c is the acceleration index; s is the expected safety distance; x n-1 (t) is the position of the n-1th intelligent connected following vehicle at time t; x n (t) is the position of the nth intelligent connected vehicle at time t; l is the length of the intelligent connected vehicle; s0 is the parking safety distance; T safe is the safety time interval; v n-1 (t) is the speed of the n-1th intelligent connected following vehicle at time t; b is the maximum braking deceleration of the vehicle.

[0057] After inserting the virtual vehicle, the vehicle spacing and acceleration of each vehicle in the intelligent connected vehicle fleet on the CAV dedicated lane at time t are calculated based on the above virtual vehicle relaxation model formula. The speed of the intelligent connected vehicle fleet is dynamically adjusted according to the calculation results until the overall speed of the fleet reaches equilibrium.

[0058] When the CAV dedicated lane space occupancy rate is large, the intelligent networked fleet changes from the free state to the following state. n-1 (t)-v n (t)<0, at this time, the following vehicle gradually approaches the leading vehicle, resulting in a larger expected vehicle spacing of the intelligent connected vehicle fleet; when the speed of the following vehicle is less than that of the leading vehicle, that is, v n-1 (t)-v n When (t)>0, the following vehicle gradually moves away from the leading vehicle, and the expected inter-vehicle distance of the intelligent connected vehicle fleet decreases. This indicates that the virtual vehicle relaxation model can adjust the expected inter-vehicle distance based on the relative speed of the leading and trailing vehicles.

[0059] Step 4: The CAV to be changed lanes changes to the CAV dedicated lane and the two CAVs adjacent to the CAV to be changed lanes in the CAV queue i 、CAVi-1 During this time, the CAV waiting to change lanes merges into the CAV queue in the CAV dedicated lane.

[0060] When the lane-changing CAV changes lanes and enters the position of the virtual vehicle, it is greatly affected by the speed and distance between surrounding vehicles. Among them, the CAV closest to the lane-changing CAV in the CAV-dedicated lane has the greatest impact on the lane-changing CAV. In order to ensure that the lane-changing CAV does not collide with the rear vehicle FV of the two adjacent CAVs in the CAV queue, a minimum safe distance D is required between the lane-changing CAV and the rear vehicle FV. min Put forward control requirements, minimum safety distance D min Related to vehicle speed, acceleration, and the relative speed between the two vehicles.

[0061] In this embodiment, the minimum safety distance D min The control formula is shown as follows:

[0062] D min ≥D FV -D CAV +l+W sinθ

[0063] Where: D FV The distance traveled by the rearmost of the two connected vehicles in the CAV lane within the lane-changing time.

[0064] D CAV is the distance traveled by the smart connected vehicle to be changed within the lane change time;

[0065] l is the length of the intelligent connected vehicle to be changed lanes;

[0066] W is the width of the intelligent connected vehicle to be changed lanes;

[0067] θ is the angle between the intelligent connected vehicle to be changed and the horizontal line when changing lanes.

[0068] That is, when changing lanes, the CAV always maintains the minimum safe distance D between itself and the following vehicle FV. min , greater than or equal to D FV -D CAV +l+W sinθ. Thus, the lane-changing CAV completes the lane change to the CAV-only lane. After the lane change, the CAV safely enters the CAV-only lane and merges into the CAV platoon, achieving stable following of the CAV platoon in the CAV-only lane.

[0069] The preferred embodiments of the present invention are described in detail above with reference to the accompanying drawings. The embodiments described in the present invention are merely descriptions of the preferred embodiments of the present invention and do not limit the concept and scope of the present invention. The various specific technical features described in the above specific embodiments can be combined in any suitable manner unless there is any contradiction. Such combinations should also be regarded as the contents disclosed in this disclosure as long as they do not violate the concept of the present invention. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0070] The present invention is not limited to the specific details of the above-mentioned embodiments. Within the scope of the technical concept of the present invention and without departing from the design concept of the present invention, various modifications and improvements made to the technical solution of the present invention by those skilled in the art should fall within the scope of protection of the present invention. The technical contents for which protection is sought in the present invention have been fully recorded in the claims.

Claims

1. A method for controlling a CAV-only lane collaborative merging control based on virtual vehicle slack, for controlling a CAV-only lane-changing vehicle to merge from a mixed lane into a CAV-only lane, characterized in that: The process is as follows: Step 1: Determine whether the lane change decision conditions are met based on the lane change decision conditions. If so, proceed to step 2. Step 2: Based on the gap selection model, determine whether the gap between two adjacent intelligent connected vehicles in the CAV dedicated lane and the intelligent connected vehicle to be changed meets the queue-jumping condition. If so, execute step 3. Step 3: Based on the virtual vehicle relaxation model, when an intelligent connected vehicle in a mixed lane attempts to change lanes to the CAV lane, a virtual vehicle is inserted between the two vehicles in the CAV platoon that are laterally adjacent to it. The acceleration and inter-vehicle spacing of the CAV platoon are dynamically adjusted based on the virtual vehicle relaxation model until the overall platoon speed reaches equilibrium. At this point, step 4 is executed. Step 4: The intelligent connected vehicle to be changed lanes changes lanes to between two adjacent intelligent connected vehicles in the intelligent connected vehicle queue of the CAV dedicated lane, completing the process of merging the intelligent connected vehicle to be changed lanes into the intelligent connected vehicle queue of the CAV dedicated lane.

2. The method for controlling the coordinated merging of intelligent connected vehicles into a dedicated lane based on virtual vehicle slack according to claim 1, characterized in that: In step 1, the lane-changing decision conditions are as follows: Condition (a): The speed difference between the intelligent connected vehicle to be changed and the speed of the one of the two adjacent intelligent connected vehicles located behind the intelligent connected vehicle to be changed in the CAV lane is greater than 2 m / s, and the speed difference between the intelligent connected vehicle to be changed and the one behind is less than or equal to 7 m / s. Condition (b): The number of vehicles behind the ICV in the CAV lane is less than or equal to 5; When both conditions (a) and (b) are met, it is determined that the lane change condition is met.

3. The method for controlling the coordinated merging of intelligent connected vehicles into a dedicated lane based on virtual vehicle slack according to claim 1, characterized in that: In step 2, the gap selection model is shown in the following formula: x i ≤x CAV ≤x i-1 -l Where: x CAV Indicates the position of the front bumper of the smart connected car to be changed lanes; x i Indicates the front bumper position of the rear-end of the two connected vehicles adjacent to the vehicle to be changed in the CAV lane; x i-1 represents the rear bumper position of the front of the two connected vehicles in the CAV lane; l represents the length of the connected vehicle in the lane to be changed; When the above gap selection model formula is satisfied, it is determined that the gap between two intelligent connected vehicles adjacent to the intelligent connected vehicle to be changed lanes in the CAV dedicated lane meets the queue-jumping condition.

4. The method for controlling the coordinated merging of intelligent connected vehicles into dedicated lanes based on virtual vehicle slack according to claim 1, characterized in that: In step 3, the virtual car relaxation model is shown in the following formula: Among them: a n (t) is the acceleration of the nth intelligent connected vehicle; A is the maximum acceleration of the intelligent connected vehicle; v n (t) is the speed of the nth intelligent connected following vehicle at time t; v f is the expected speed of the intelligent connected vehicle fleet; c is the acceleration index; s is the expected safety distance; x n-1 (t) is the position of the n-1th intelligent connected following vehicle at time t; x n (t) is the position of the nth intelligent connected vehicle at time t; l is the length of the intelligent connected vehicle; s0 is the parking safety distance; T saft is the safety time interval; v n-1 (t) is the speed of the n-1th intelligent connected following vehicle at time t; b is the maximum braking deceleration of the vehicle. After inserting the virtual vehicle, the vehicle spacing and acceleration of each vehicle in the intelligent connected vehicle fleet on the CAV dedicated lane at time t are calculated based on the above virtual vehicle relaxation model formula. The speed of the intelligent connected vehicle fleet is dynamically adjusted according to the calculation results until the overall speed of the fleet reaches equilibrium.

5. The method for controlling the coordinated merging of intelligent connected vehicles into dedicated lanes based on virtual vehicle slack according to claim 1, characterized in that: When the intelligent connected vehicle to be changed lanes in step 4 changes lanes, a minimum safe distance is controlled between the intelligent connected vehicle to be changed lanes and the rear one of the two adjacent intelligent connected vehicles in the intelligent connected vehicle queue to avoid collision with the rear one.

6. The method for controlling the coordinated merging of intelligent connected vehicles into a dedicated lane based on virtual vehicle slack according to claim 5, characterized in that: Minimum safety distance D min The control formula is shown as follows: D min ≥D FV -D CAV +l+W sinθ Where: D FV The distance traveled by the rearmost of the two connected vehicles in the CAV lane within the lane-changing time. D CAV is the distance traveled by the smart connected vehicle to be changed within the lane change time; l is the length of the intelligent connected vehicle to be changed lanes; W is the width of the intelligent connected vehicle to be changed lanes; θ is the angle between the intelligent connected vehicle to be changed and the horizontal line when changing lanes.

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