Collaborative formation driving control system and method based on vehicle-to-vehicle communication

Abstract

The invention discloses a cooperative formation driving control system and method based on vehicle-to-vehicle communication, and the system comprises a perception and communication layer, a decision and control layer and an execution and interaction layer which are sequentially arranged, and the perception and communication layer comprises a vehicle-to-vehicle communication module and an environment perception module. The decision-making and control layer comprises a decision-making control module and a cooperative control unit, and the execution and interaction layer comprises a vehicle execution mechanism and a human-computer interaction interface; the vehicle-to-vehicle communication module is used for data exchange between the vehicle and other vehicles in the formation; the environment sensing module is used for detecting the surrounding environment of the vehicle; the decision control module is used for decision control and generating a vehicle control instruction; the cooperative control unit is used for calculating a control instruction of the vehicle; and the vehicle execution mechanism is used for responding to the vehicle control instruction of the decision control module to realize automatic driving operation. According to the cooperative formation driving control system based on vehicle-vehicle communication, safe and efficient application of a cooperative formation driving control technology in a real and open road environment can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of networked vehicle platoon control, and more particularly to a cooperative platoon driving control system and method based on vehicle-to-vehicle communication. BACKGROUND

[0002] Vehicle cooperative platoon driving control is a cutting-edge research direction in the field of intelligent transportation systems and autonomous driving. The core idea is to let multiple vehicles form a closely coordinated driving cluster through wireless communication and cooperative control technology. In an ideal state, the following vehicles in the platoon can follow the trajectory of the leading vehicle, taking advantage of the "break wind" effect generated by the leading vehicle to significantly reduce air resistance, thereby achieving energy savings of up to 10%-20%. In addition, this technology can free the following vehicle drivers from continuous driving operations, greatly reducing the fatigue of long-distance driving, and through cooperative decision-making and control between vehicles, it can reduce human reaction delays and improve driving safety, and increase road capacity by maintaining a stable and small vehicle distance.

[0003] Although this concept has broad prospects, there are many technical challenges in achieving safe, efficient, and practical cooperative platoon. Existing research and patent technology solutions attempt to address these issues from different angles, but all have certain limitations. The existing technology presents a "each for itself" situation: some algorithms are advanced but are detached from real-time control needs, some are limited to specific scenarios and lack universality, and some only solve high-level planning problems without underlying control support. Currently, the industry still lacks a general, real-time, safe, and complete closed-loop function (from platoon formation, driving to disband) cooperative platoon driving control system solution. In particular, there is a lack of a universal method that is based on low-latency, high-reliability vehicle-to-vehicle direct communication, integrates multi-level sensor redundancy, and has a strong safety arbitration mechanism built in.

[0004] Therefore, there is an urgent need for a cooperative platoon driving control system and method based on vehicle-to-vehicle communication. SUMMARY

[0005] The purpose of the present application is to provide a cooperative platoon driving control system and method based on vehicle-to-vehicle communication to solve the problems in the above-mentioned prior art and enable the safe and efficient application of cooperative platoon driving control technology in real and open road environments.

[0006] The present application provides a cooperative platoon driving control system based on vehicle-to-vehicle communication, which comprises a perception and communication layer, a decision and control layer, and an execution and interaction layer arranged in sequence, wherein the perception and communication layer comprises a vehicle-to-vehicle communication module and an environment perception module, the decision and control layer comprises a decision control module and a cooperative control unit, and the execution and interaction layer comprises a vehicle execution mechanism and a human-computer interaction interface.

[0007] The vehicle-to-vehicle communication module is configured to exchange data between the host vehicle and other vehicles in the platoon.

[0008] The environment perception module is configured to detect the environment around the host vehicle.

[0009] The decision and control module is configured to make decision and control based on the data obtained by the vehicle-to-vehicle communication module and the environment perception module, and generate vehicle control instructions.

[0010] The cooperative control unit is configured to calculate the host vehicle control instructions based on the data obtained by the vehicle-to-vehicle communication module and the environment perception module, so that the host vehicle maintains a safe distance and consistent driving trajectory with the preceding vehicle, while ensuring smooth driving.

[0011] The vehicle execution mechanism is configured to respond to the vehicle control instructions of the decision and control module to realize automatic driving operation.

[0012] The human-machine interaction interface is configured to display the platoon state to the driver, issue a takeover request, and allow the driver to initiate a request to join the platoon or a request to exit the platoon.

[0013] The cooperative platoon driving control system based on vehicle-to-vehicle communication as described above, wherein preferably, the vehicle-to-vehicle communication module includes a direct communication unit based on 5G-V2X PC5 interface or DSRC technology.

[0014] The data transmitted by the vehicle-to-vehicle communication module uses periodic basic safety messages as a carrier, and at least includes the real-time position, speed, acceleration, heading angle, turn signal state, brake pedal opening, and vehicle unique identifier and platoon role of the host vehicle.

[0015] The environment perception module includes at least one of a millimeter wave radar, a laser radar, and a camera.

[0016] The cooperative platoon driving control system based on vehicle-to-vehicle communication as described above, wherein preferably, the decision and control layer further includes a platoon management unit and a safety arbitration unit, wherein:

[0017] The platoon management unit is configured to process platoon requests.

[0018] The safety arbitration unit is configured to continuously monitor the system state and immediately trigger a safety policy when a safety policy trigger condition is detected.

[0019] The cooperative platooning control system based on vehicle-to-vehicle communication as described above, preferably, the platoon management unit is configured to receive a joining application of a rear vehicle, or process an exit request of a vehicle in the platoon, and specifically configured to determine whether to allow a new vehicle to join according to a preset strategy, the preset strategy including at least one of vehicle model, system compatibility and destination matching degree.

[0020] The cooperative platooning control system based on vehicle-to-vehicle communication as described above, preferably, the safety arbitration unit has the highest priority; the safety strategy triggering condition of the safety arbitration unit includes communication interruption, sensor failure, other vehicle cutting in or sudden danger in front, and the safety strategy includes smoothly exiting the platoon mode and switching to basic auxiliary driving or sending a takeover reminder to the driver.

[0021] The present application also provides a cooperative platooning control method based on vehicle-to-vehicle communication using the above system, comprising the following steps:

[0022] The platoon formation stage: the driver of the potential following vehicle initiates the platoon search instruction through the human-machine interface, and the vehicle broadcasts the search signal through the vehicle-to-vehicle communication module; the head vehicle of the existing platoon or the platoon allowing to join sends a response after receiving the signal, the following vehicle and the head vehicle establish a communication link, exchange platoon parameters, the following vehicle automatically accelerates or decelerates, adjusts its own position, and safely enters the platoon sequence;

[0023] The platoon driving stage: the motion state of the head vehicle is broadcast in real time to all following vehicles through the vehicle-to-vehicle communication module, and the cooperative control unit of each following vehicle calculates the optimal control amount based on the state of the front vehicle and the state of the vehicle, so that the vehicle maintains a safe distance with the front vehicle, the whole platoon responds to the operation of the head vehicle in a coordinated and consistent manner, and a train-like linkage effect is formed;

[0024] The platoon disbanding or vehicle exit stage.

[0025] The cooperative platooning control method based on vehicle-to-vehicle communication as described above, preferably, the platoon disbanding or vehicle exit stage includes active exit, platoon disbanding and emergency exit, wherein:

[0026] The active exit includes: the driver issues an exit instruction, the vehicle sends an exit signal to the platoon, and then smoothly accelerates or decelerates to safely leave the platoon;

[0027] The platoon disbanding includes: the head vehicle driver issues a disbanding instruction, the vehicles in the platoon are safely separated in order, and the single vehicle driving mode is restored;

[0028] The emergency exit includes: when the safety arbitration unit detects a danger, the vehicle is forced to exit the platoon, and an alarm is given to remind the driver to take over.

[0029] The cooperative platooning control method based on vehicle-to-vehicle communication as described above, preferably, the normal platooning strategy in the platooning stage comprises a follow-the-leader model,

[0030] The follow-the-leader model specifically comprises: role definition is divided into a leading vehicle and a following vehicle, wherein the leading vehicle is a leader of the platoon, can be driven by a driver or started automatically, and broadcasts its own motion state; the following vehicle is a member of the platoon, follows cooperative control instructions, and each following vehicle mainly communicates and tracks a directly preceding vehicle; and the follow-the-leader model adopts a constant time distance + minimum safety distance spacing strategy,

[0031] The following distance is calculated by the following formula:

[0032] D_desired = max(D_min, V*T),

[0033] Wherein, D_desired represents the following distance, V represents the speed of the vehicle, T represents a preset fixed time distance, and D_min represents a minimum physical safety distance.

[0034] The cooperative platooning control method based on vehicle-to-vehicle communication as described above, preferably, the redundancy backup and abnormality handling strategy in the platooning stage comprises a soft isolation and reorganization strategy in the case of communication failure of a vehicle in the platoon or vehicle itself failure, an adaptive inclusion strategy in the case of external vehicle cutting into the platoon, and a replacement leader strategy in the case of abnormal exit of the leading vehicle,

[0035] The soft isolation and reorganization strategy in the case of communication failure of a vehicle in the platoon or vehicle itself failure comprises:

[0036] If any vehicle does not receive a heartbeat signal of its directly preceding vehicle for 3 consecutive communication periods, it is determined that the communication with the preceding vehicle is interrupted; if a key system failure is detected by a vehicle self-diagnosis system and an emergency failure code is broadcast through a vehicle-to-vehicle communication module,

[0037] The failure vehicle itself immediately flashes a double flash warning, the safety arbitration unit of the failure vehicle is triggered, the vehicle is controlled to decelerate smoothly, and the failure vehicle attempts to safely drive into an emergency lane; after the rear following vehicle detects that the preceding vehicle communication is lost or receives the failure code of the failure vehicle, the safety arbitration unit of the rear following vehicle immediately takes over the control, the control strategy is switched from cooperative following to emergency independent risk avoidance, based on an environment perception module of the vehicle, first, ensure that no collision occurs with the failure vehicle. Under the premise of ensuring safety, attempt to re-establish a communication link with the directly preceding vehicle;

[0038] If the rear vehicle successfully establishes a connection with the front vehicle, the platoon automatically reorganizes after skipping the faulty vehicle, forms a new platoon sequence, and informs all drivers of the platoon state change and the position of the faulty vehicle through the human-machine interface; if the connection fails to be established, the platoon is safely dispersed, and the system prompts the driver to take over,

[0039] The adaptive inclusion strategy in the case of the external vehicle cutting into the platoon includes:

[0040] The environment perception module of the vehicle identifies that a vehicle has cut in between the vehicle and the directly front vehicle, and the vehicle-to-vehicle communication system of each vehicle ensures that the perception information is shared between the platoon vehicles and cross-verified.

[0041] After the following vehicle detects the cutting-in vehicle, the vehicle-to-vehicle communication module is used to share the cutting-in information with the rear vehicle to confirm that the cutting-in behavior is stable, and after confirmation, the following vehicle regards the cutting-in vehicle as a new, non-cooperative temporary front vehicle, and the cooperative control unit of the following vehicle dynamically adjusts the following target and appropriately increases the following distance from the cutting-in vehicle to ensure safety.

[0042] The entire platoon regards this event as a common disturbance, the rear vehicle continues to follow the directly front vehicle, and the entire platoon smoothly passes through this disturbance without disbanding the platoon, and if the cutting-in vehicle drives away, the platoon vehicles automatically and smoothly reduce the distance and restore to the preset optimal following state after detecting the restored space,

[0043] The replacement head vehicle strategy in the case of abnormal exit of the head vehicle includes:

[0044] If the head vehicle voluntarily exits, the head vehicle driver issues an exit instruction, the system automatically designates the second vehicle in the platoon as a new head vehicle, and completes the leadership switch instantly, and the original head vehicle smoothly accelerates or decelerates to change lanes and leave the platoon.

[0045] If the head vehicle suddenly fails, the head vehicle broadcasts the fault code through the vehicle-to-vehicle communication module and starts to decelerate, and after the second vehicle detects the fault code of the head vehicle, the platoon management unit of the second vehicle immediately promotes itself to the head vehicle and takes over the piloting responsibility, and controls the platoon to safely decelerate or change lanes to avoid risks.

[0046] The cooperative platoon driving control method based on vehicle-to-vehicle communication as described above, wherein preferably, in any abnormal processing process, the safety arbitration unit follows the following highest priority principle: the safety of the vehicle first: if any cooperative instruction conflicts with the emergency collision avoidance requirement judged by the local sensor, the local judgment is given priority; step-down: cooperative platoon -> independent adaptive cruise -> emergency braking -> alarm and request the driver to take over; information sharing: when any vehicle triggers a safety strategy, the vehicle must broadcast the dangerous information and its intention to all vehicles in the platoon through the vehicle-to-vehicle communication module to achieve cooperative early warning of danger.

[0047] The application provides a cooperative platoon driving control system and method based on vehicle-to-vehicle communication. Based on vehicle-to-vehicle communication, the automatic formation, stable following and safe dispersion of a platoon are realized through an inter-vehicle self-organizing network, self-organizing platoon management is realized, no external infrastructure is needed, no central scheduling is needed, real traffic flow can be adapted, strong adaptability and flexibility are achieved, the following vehicle receives real-time motion data of the front vehicle and controls the self-execution mechanism to perform synchronous operation, stable and energy-saving close-range following is realized, cooperative following control is realized, the wind resistance of the rear vehicle is greatly reduced under the wind-breaking effect of the front vehicle, energy saving of up to 10%-20% of fuel or electricity is achieved, the driver of the rear vehicle is liberated from repetitive driving operation, fatigue is reduced, safety and comfort are improved, and a more stable riding experience is provided, the distance between the platoon vehicles is small and stable, the traffic efficiency of the highway can be improved, and the road capacity can be increased, through multi-level safety redundancy design (communication + perception + safety arbitration), it is ensured that a single node failure will not cause an accident, and the safety is high. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to make the object, technical scheme and advantages of the present application clearer, the present application will be further described below with reference to the drawings, in which:

[0049] Figure 1 The structure block diagram of the cooperative platoon driving control system based on vehicle-to-vehicle communication provided by the present application is shown in the figure.

[0050] Figure 2 The flowchart of the cooperative platoon driving control system based on vehicle-to-vehicle communication provided by the present application is shown in the figure.

[0051] Figure 3 The redundancy backup and abnormality processing strategy flowchart of the platoon driving stage is shown in the figure.

[0052] Figure 4 The platoon driving scene schematic diagram is shown in the figure.

[0053] Explanation of reference signs: 1-vehicle-to-vehicle communication module, 2-environment perception module, 3-platoon management unit, 4-cooperative control unit, 5-safety arbitration unit, 6-decision control module, 7-vehicle execution mechanism, 8-human-machine interaction interface. DETAILED DESCRIPTION

[0054] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative in nature and is in no way intended to limit the disclosure, its application or uses. The disclosure can be implemented in numerous different forms, not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the disclosure to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangement of components and steps set forth in these embodiments, the composition of materials, numerical expressions, and numerical values should be interpreted as merely exemplary, rather than as a limitation.

[0055] The "first", "second", and similar words used in the present disclosure do not represent any order, number or importance, but are only used to distinguish different parts. "Include" or "contain" and similar words mean that the elements before the word cover the elements listed after the word, and do not exclude the possibility of also covering other elements. "Up", "down" and the like are only used to represent the relative positional relationship, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0056] In the present disclosure, when it is described that a specific component is located between a first component and a second component, there can be an intervening component between the specific component and the first component or the second component, or there can be no intervening component. When it is described that a specific component is connected to other components, the specific component can be directly connected to the other components without an intervening component, or it can not be directly connected to the other components with an intervening component.

[0057] All terms used in the present disclosure, including technical terms or scientific terms, have the same meaning as understood by those skilled in the art to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted to have meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or excessively formalized sense, unless specifically defined here.

[0058] Techniques, methods and equipment known to those skilled in the relevant art can not be discussed in detail, but in appropriate cases, the techniques, methods and equipment should be considered as part of the specification.

[0059] The existing vehicle cooperative platoon technical solutions present diversified technical paths, some solutions focus on improving the accuracy and stability of platoon driving through optimization control algorithm; some solutions are designed for specific application scenarios, such as mixed platoon mode composed of manually driven lead trucks and unmanned following trucks; some technical solutions focus on high-level decision and path planning of platoon, using search algorithm and fuzzy judgment algorithm to dynamically decide where to platoon in the road network.

[0060] The disadvantages of the existing vehicle cooperative platoon technical solutions are as follows: the existing optimization control algorithm aims to improve control accuracy, but it relies on multiple iterations of model training and parameter transmission, has large communication overhead, and may not have sufficient real-time responsiveness, and is difficult to cope with emergency working conditions requiring millisecond-level response in highway scenarios; the application field of the existing technology is too specific, and the system architecture and logic are tightly coupled with specific vertical scenes such as freight logistics, lack of universality, and are difficult to migrate to more general applications such as ordinary passenger car platooning; the existing technology solves the macro planning problem of "when and where to platoon", but does not provide specific and effective technical means for the real-time, safe and smooth micro cooperative following control between vehicles after the formation of the platoon.

[0061] As shown in Figure 1 The cooperative platoon driving control system based on vehicle-to-vehicle communication provided by the embodiment includes a perception and communication layer, a decision and control layer, and an execution and interaction layer arranged in sequence, the perception and communication layer includes a vehicle-to-vehicle communication module 1 and an environment perception module 2, the decision and control layer includes a decision control module 6 and a cooperative control unit 4, and the execution and interaction layer includes a vehicle execution mechanism 7 and a human-machine interaction interface 8.

[0062] The vehicle-to-vehicle communication module 1 is configured to exchange data between the vehicle and other vehicles in the platoon.

[0063] The environment perception module 2 is configured to detect the environment around the vehicle.

[0064] The decision control module 6 is configured to perform decision control and generate vehicle control instructions based on the data obtained by the vehicle-to-vehicle communication module 1 and the environment perception module 2.

[0065] The cooperative control unit 4 is configured to calculate the vehicle control instructions based on the data obtained by the vehicle-to-vehicle communication module 1 and the environment perception module 2, so that the vehicle maintains a safe distance and consistent driving trajectory with the preceding vehicle, while ensuring the smoothness of driving.

[0066] The vehicle execution mechanism 7 is configured to respond to the vehicle control instructions of the decision control module 6 to implement automatic driving operation.

[0067] The human-machine interaction interface (HMI) 8 is configured to display the platoon state to the driver, issue a takeover request, and allow the driver to initiate a platoon joining instruction or a platoon exiting instruction.

[0068] The human-machine interaction interface (HMI) 8 is, for example, a central control screen, and the platoon state displayed by the human-machine interaction interface 8 includes "in platoon", "looking for platoon", etc.

[0069] The vehicle-to-vehicle communication module 1 comprises a direct communication unit based on 5G-V2X PC5 interface or DSRC (IEEE 802.11p) technology, for low-latency and high-reliability data exchange with other vehicles in the platoon, especially the front vehicle and the lead vehicle.

[0070] The data transmitted by the vehicle-to-vehicle communication module 1 is carried by periodic basic safety messages (such as BSM, CAM), and at least includes: real-time position, speed, acceleration, heading angle, turn signal state, brake pedal opening, and vehicle unique identifier and platoon role (such as lead vehicle, following vehicle) of the vehicle. In a specific implementation, the vehicle-to-vehicle communication module 1 supports high-frequency information broadcast at least 10 times per second (100 ms / time), and the end-to-end communication delay is required to be less than 50 milliseconds, to meet the stringent real-time requirements of platoon cooperative control.

[0071] Further, the cooperative control unit 4 is specifically configured to calculate the throttle, brake and steering control instructions of the vehicle according to the motion state information of the front vehicle (or the lead vehicle) obtained by the vehicle-to-vehicle communication module 1, and in combination with the data of the environment perception module. The vehicle actuator 7 is specifically configured to receive the instructions of the decision control module 6, and accurately control the throttle, brake and steering system of the vehicle to realize automatic driving operation.

[0072] Further, the environment perception module 2 comprises at least one of a millimeter wave radar, a laser radar and a camera. Through the environment perception module 2, lane lines, obstacles and other non-platoon vehicles can be identified, to provide local environment information for platoon control.

[0073] Further, the decision and control layer further comprises: a platoon management unit 3 and a safety arbitration unit 5, wherein:

[0074] The platoon management unit 3 is configured to process platoon requests;

[0075] The safety arbitration unit 5 is configured to continuously monitor the system state, and immediately trigger a safety policy when detecting that a safety policy trigger condition is met.

[0076] Specifically, the platoon management unit 3 is configured to receive a joining application of a rear vehicle, or process an exit request of a vehicle in the platoon, and is specifically configured to judge whether to allow a new vehicle to join according to a preset policy, the preset policy comprising at least one of vehicle type, system compatibility and destination matching degree.

[0077] Further, in the present application, the safety arbitration unit 5 has the highest priority level; the safety policy trigger condition of the safety arbitration unit 5 includes communication interruption, sensor failure, other vehicles cutting in, or sudden danger ahead (such as the preceding vehicle emergency braking), and the safety policy includes smoothly exiting the platoon mode and switching to basic auxiliary driving or sending a takeover reminder to the driver.

[0078] As shown in the embodiment provided by the present application, the cooperative platoon driving control method based on vehicle-to-vehicle communication specifically includes the following steps in actual execution process: Figure 2

[0079] Step S1, platoon formation stage: the driver of the potential following vehicle initiates the platoon searching instruction through the human-computer interaction interface 8, and the vehicle broadcasts a search signal through the vehicle-to-vehicle communication module 1. After receiving the signal, the head vehicle of the existing platoon or the platoon allowing to join sends a response, the following vehicle and the head vehicle establish a communication link, exchange platoon parameters, the following vehicle automatically accelerates or decelerates, adjusts its own position, and safely joins the platoon sequence.

[0080] For example, the platoon parameters can be desired vehicle distance and cruise speed.

[0081] In specific implementation, the driver of the vehicle selects "search and apply to join the platoon" through the human-computer interaction interface 8 to initiate the platoon process. The human-computer interaction interface 8 transmits the driver's instruction to the decision and control layer (specifically, the platoon management unit 3), and converts the instruction into a system signal. The platoon management unit 3 triggers the vehicle-to-vehicle communication module 1 to broadcast a "platoon joining request" signal and actively search for available platoons.

[0082] The vehicle-to-vehicle communication module 1 receives the "response signal" and the platoon parameters (such as target speed and allowed vehicle distance) from the head vehicle, establishes a communication link, the platoon management unit 3 confirms and accepts the platoon parameters, issues a "start merging" instruction to the cooperative control unit 4, and approves to enter the automatic control stage. The cooperative control unit 4 continuously receives the real-time state (speed, position) of the head vehicle / preceding vehicle through the vehicle-to-vehicle communication module 1, obtains the surrounding environment of the vehicle through the environment perception module 2, and ensures the safety of the merging path. Based on the above inputs, the required acceleration and steering angle of the vehicle are calculated, and a safe and smooth merging trajectory is planned.

[0083] Step S2, platoon driving stage: the motion state of the head vehicle is broadcast in real time to all following vehicles through the vehicle-to-vehicle communication module 1, and the cooperative control unit 4 of each following vehicle calculates the optimal control amount based on the state of the preceding vehicle and the state of the vehicle, so that the vehicle and the preceding vehicle maintain a safe distance in a dynamic stable state. The whole platoon responds to the operation of the head vehicle in a cooperative and consistent manner, forming a train-like linkage effect.

[0084] ​The head vehicle is driven by a driver or is started in automatic driving, and the motion state of the head vehicle is, for example, acceleration, steering angle, etc. The cooperative control unit 4 of each following vehicle calculates an optimal control amount based on the state of the preceding vehicle and the state of the vehicle itself by using a predictive control model, so that the vehicle itself and the preceding vehicle maintain a safe distance in a dynamic stable manner.

[0085] In an embodiment of the application, the cooperative control unit 4 sends the calculated control instructions (accelerator, brake, steering) to the vehicle execution mechanism 7 to accurately control the vehicle action. The vehicle execution mechanism 7 executes the instructions, and the vehicle automatically accelerates, decelerates or turns, smoothly enters the platoon sequence, and realizes automatic driving. The man-machine interaction interface 8 displays the state feedback of "in the process of merging into the platoon..." and "in the platoon..." to the driver.

[0086] Further, the normal platoon strategy in the platoon driving stage includes a series car-following model,

[0087] The series car-following model specifically includes role definition into a head vehicle and a following vehicle. The head vehicle is the leader of the platoon, can be driven by a driver or started in automatic driving, is responsible for setting a cruise speed, initiating a lane change, etc., and broadcasts its own motion state. The following vehicle is a member of the platoon, follows cooperative control instructions, and the main communication and tracking object of each following vehicle is the directly preceding vehicle, not only the head vehicle. This series structure avoids single-point failure leading to paralysis of the entire platoon. The series car-following model adopts a constant time distance + minimum safe distance spacing strategy,

[0088] The following distance is calculated by the following formula:

[0089] D_desired = max(D_min, V*T),

[0090] Wherein, D_desired represents the following distance, V represents the speed of the vehicle, T represents a preset fixed time distance, and D_min represents the minimum physical safe distance. This strategy can balance safety and efficiency at different speeds.

[0091] Further, as shown in the figure, Figure 3 The redundancy backup and abnormality processing strategy in the platoon driving stage includes a soft isolation and reorganization strategy in the case of communication failure of a vehicle in the platoon or vehicle itself failure, an adaptive inclusion strategy in the case of external vehicle cutting into the platoon, and a head vehicle replacement strategy in the case of abnormal exit of the head vehicle.

[0092] Specifically, the soft isolation and reorganization strategy in the case of communication failure of a vehicle in the platoon or vehicle itself failure (i.e., vehicle failure) includes:

[0093] If any vehicle does not receive the heartbeat signal from its direct front vehicle for 3 consecutive communication cycles (e.g. 300 ms), it is determined that the communication with the front vehicle is interrupted; if the vehicle's self-diagnosis system detects a fault in a critical system (e.g. drive system, brake system) and broadcasts an emergency fault code through the vehicle-to-vehicle communication module 1;

[0094] The faulty vehicle itself immediately flashes a double warning light, the safety arbitration unit 5 of the faulty vehicle is triggered, and the vehicle is controlled to decelerate smoothly and attempt to safely enter the emergency lane. After the rear following vehicle detects that the front vehicle communication is lost or receives the fault code of the faulty vehicle, the safety arbitration unit 5 of the rear following vehicle immediately takes control, and the control strategy is switched from cooperative following to emergency independent risk avoidance. Based on the environmental perception module 2 of the vehicle, it is first ensured that there is no collision with the faulty vehicle. Under the premise of safety, it attempts to re-establish a communication link with the front front vehicle (i.e. the front vehicle of the faulty vehicle).

[0095] If the rear vehicle successfully establishes a connection with the front front vehicle, the platoon automatically reorganizes after skipping the faulty vehicle, forms a new platoon sequence, and informs all drivers of the platoon state change and the position of the faulty vehicle through the human-machine interaction interface 8; if the connection fails, the platoon is safely dissolved, and the driver is prompted to take over.

[0096] Further, the adaptive inclusion strategy under the condition of external vehicle cutting into the platoon (i.e. cutting in) includes:

[0097] The environmental perception module 2 of the vehicle identifies that a vehicle has cut in between the vehicle and the direct front vehicle, and ensures that the platoon vehicles share perception information through the vehicle-to-vehicle communication system to cross-verify;

[0098] Upon detection of the cutting-in vehicle by the following vehicle, instead of immediately taking emergency braking, the following vehicle first shares the cutting-in information with the rear vehicle through the vehicle-to-vehicle communication module 1 to confirm that the cutting-in behavior is stable (the vehicle is not temporarily changing lanes), and after confirmation, the following vehicle considers the cutting-in vehicle as a new, non-cooperative temporary front vehicle. The cooperative control unit 4 of the following vehicle will dynamically adjust the following target and increase the following distance from the cutting-in vehicle to ensure safety.

[0099] The entire platoon regards this event as a common disturbance, and the rear vehicles continue to follow their direct front vehicles, and the entire platoon smoothly passes through this disturbance without the need to disband the platoon. If the cutting-in vehicle drives away, the platoon vehicles will automatically and smoothly reduce the vehicle distance and return to the preset optimal following state after detecting the restoration of space.

[0100] Further, the replacement head vehicle strategy under the condition of abnormal exit of the head vehicle (i.e. driver takeover or fault) includes:

[0101] If the head car voluntarily exits, the head car driver issues an exit command, the system automatically designates the second car in the platoon as the new head car, and instantaneously completes the leadership switch, and the original head car smoothly accelerates or decelerates and leaves the platoon;

[0102] If the head car suddenly fails, the head car broadcasts the fault code through the vehicle-to-vehicle communication module 1 and starts to decelerate, and after the second car detects the fault code of the head car, the platoon management unit 3 of the second car immediately promotes itself to the head car, takes over the navigation responsibility, and controls the platoon to safely decelerate or change lanes to avoid risks.

[0103] Through the redundancy backup and abnormal processing strategy, various sudden events in the vehicle driving process are fully considered, the safety during the platoon driving process is guaranteed, and the ability to handle sudden events is improved.

[0104] In any abnormal processing process, the safety arbitration unit 5 follows the following highest priority principle: the safety of the vehicle first: any cooperative command conflicts with the emergency collision avoidance requirement judged by the local sensor, and the local judgment is used as the reference; Gradually degrade: cooperative platoon -> independent adaptive cruise -> emergency braking -> alarm and request the driver to take over; Information sharing: when any vehicle triggers a safety strategy, the vehicle must broadcast the danger information and its intention to all vehicles in the platoon through the vehicle-to-vehicle communication module 1, and realize danger cooperative early warning.

[0105] In the platoon driving stage, the safety arbitration unit 5 monitors throughout the process to ensure the absolute safety of the whole process as the highest priority safety redundancy. The platoon strategy of the application is a multi-level and multi-mode dynamic control process, and the core design concept is: efficient cooperation in normal state and safe degradation in abnormal state.

[0106] Step S3, platoon disbanding or vehicle exit stage.

[0107] The platoon disbanding or vehicle exit stage includes: voluntary exit, platoon disbanding, and emergency exit, specifically:

[0108] The voluntary exit includes: the driver issues an exit command, the vehicle sends an exit signal to the platoon, and then smoothly accelerates or decelerates to safely leave the platoon;

[0109] The platoon disbanding includes: the head car driver issues a disbanding command, the vehicles in the platoon safely separate in order, and return to single-vehicle driving mode;

[0110] The emergency exit includes: when the safety arbitration unit 5 detects a danger, the vehicle is forced to exit the platoon, and an alarm is given to remind the driver to take over.

[0111] In one embodiment of the application, as Figure 4As shown, taking the formation of three electric vehicles of the same brand on the highway as an example. The head vehicle (A) starts the system and sets the cruise speed to 100 km / h. The drivers of the rear vehicles (B, C) select "join the formation" through the human-computer interaction interface 8, and the system automatically establishes communication with A. B first accelerates to approach A, merges into the rear at a safe distance, and starts to synchronize the acceleration and deceleration of A. C merges into the rear of B in the same way. The three vehicles maintain a distance of 20 meters (much smaller than the safe braking distance, because the system reacts faster), as shown in Figure 4 .

[0112] When A brakes slightly due to road conditions, B and C almost simultaneously brake, and the whole process is smooth without jerk. During formation driving, the environmental perception module 2 of C suddenly detects an obstacle in front, but the radar data is inconsistent with the data received from B. The safety arbitration unit 5 determines that there is a potential risk, immediately alarms the driver of C, and controls C to smoothly increase the distance from B until the driver takes over or the risk is removed.

[0113] The cooperative formation driving control system and method based on vehicle-to-vehicle communication provided by the embodiment of the present application can realize automatic formation, stable following and safe disbanding of the formation through vehicle-to-vehicle communication and self-organizing network between vehicles, realize self-organizing formation management, do not need to rely on external infrastructure, do not need central scheduling, can adapt to real traffic flow, and have strong adaptability and flexibility; the following vehicle receives the motion data of the front vehicle in real time, and controls the self-execution mechanism to perform synchronous operation, realizes stable and energy-saving close following, realizes cooperative following control, the wind resistance of the rear vehicle is greatly reduced under the breaking wind effect of the head vehicle, and energy can be saved by up to 10%-20%. The driver of the rear vehicle is liberated from repetitive driving operation, fatigue is reduced, safety and comfort are improved, and a more stable driving experience is provided. The distance between the formation vehicles is small and stable, the passing efficiency of the highway can be improved, and the road capacity can be increased. Through multi-level safety redundancy design (communication + perception + safety arbitration), it is ensured that a single node failure will not cause an accident, and the safety is high.

[0114] So far, the embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein according to the above description.

[0115] Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration, and are not intended to limit the scope of the present disclosure. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be replaced equivalently without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A cooperative platooning control system based on car-to-car communication, characterized by, Comprise: The perception and communication layer, decision and control layer and execution and interaction layer are sequentially arranged, the perception and communication layer comprises a vehicle-to-vehicle communication module and an environment perception module, the decision and control layer comprises a decision control module and a cooperative control unit, and the execution and interaction layer comprises a vehicle execution mechanism and a man-machine interaction interface; The vehicle-to-vehicle communication module is used for data exchange between the vehicle and other vehicles in the platoon; The environment perception module is used for detecting the surrounding environment of the vehicle; The decision control module is used for decision control according to the data obtained by the vehicle-to-vehicle communication module and the environment perception module, and generating vehicle control instructions; The cooperative control unit is used for calculating the vehicle control instructions according to the data obtained by the vehicle-to-vehicle communication module and the environment perception module, so that the vehicle maintains a safe distance and consistent driving trajectory with the front vehicle, while ensuring the smoothness of driving; The vehicle execution mechanism is used for automatic driving operation in response to the vehicle control instructions of the decision control module; The man-machine interaction interface is used for displaying the platoon state to the driver, issuing a takeover request, and allowing the driver to initiate a platoon joining instruction or a platoon exiting instruction.

2. The cooperative platooning control system based on vehicle-to-vehicle communication according to claim 1, characterized by, The vehicle-to-vehicle communication module comprises a direct communication unit based on 5G-V2X PC5 interface or DSRC technology; The data transmitted by the vehicle-to-vehicle communication module takes a periodic basic safety message as a carrier and at least includes the real-time position, speed, acceleration, heading angle, turn signal state, brake pedal opening, and vehicle unique identifier and platoon role of the vehicle; The environment perception module comprises at least one of a millimeter wave radar, a laser radar and a camera.

3. The cooperative platooning control system based on vehicle-to-vehicle communication according to claim 1, characterized by, The decision and control layer further comprises a platoon management unit and a safety arbitration unit, wherein: The platoon management unit is used for processing platoon requests; The safety arbitration unit is used for continuously monitoring the system state and triggering a safety policy when detecting that the safety policy trigger condition is met.

4. The cooperative platooning control system based on vehicle-to-vehicle communication according to claim 3, characterized by, The platoon management unit is used for receiving the joining application of the rear vehicle or processing the exit request of the vehicle in the platoon, and is specifically used for judging whether to allow a new vehicle to join according to a preset policy, the preset policy comprising at least one of vehicle type, system compatibility and destination matching degree.

5. The cooperative platooning control system based on vehicle-to-vehicle communication according to claim 3, characterized by, The safety arbitration unit has the highest priority; the safety policy trigger condition of the safety arbitration unit comprises communication interruption, sensor failure, other vehicle cutting in or sudden danger in front, and the safety policy comprises a smooth platoon exit mode and switching to basic auxiliary driving or sending a takeover reminder to the driver.

6. A cooperative platooning control method based on vehicle-to-vehicle communication using the system according to any one of claims 1 to 5, characterized by, Comprise: The platoon formation stage: the driver of the potential following vehicle initiates a platoon search instruction through the man-machine interaction interface, the vehicle broadcasts a search signal through the vehicle-to-vehicle communication module, the head vehicle of the existing platoon or the platoon allowing to join sends a response after receiving the signal, the following vehicle and the head vehicle establish a communication link, exchange platoon parameters, the following vehicle automatically accelerates or decelerates, adjusts its own position, and safely enters the platoon sequence; The platoon driving stage: the motion state of the head vehicle is broadcast in real time to all following vehicles through the vehicle-to-vehicle communication module, and the cooperative control unit of each following vehicle calculates the optimal control amount based on the state of the preceding vehicle and the state of the vehicle, so that the vehicle maintains a safe distance with the preceding vehicle, and the whole platoon responds to the operation of the head vehicle in a coordinated manner, forming a train-like linkage effect. The platoon disbanding or vehicle exiting stage.

7. The cooperative platooning control method based on vehicle-to-vehicle communication according to claim 6, characterized by, The platoon disbanding or vehicle exiting stage includes active exiting, platoon disbanding and emergency exiting, wherein: The active exiting includes that the driver issues an exiting instruction, the vehicle sends an exiting signal to the platoon, and then smoothly accelerates or decelerates to safely drive away from the platoon. The platoon disbanding includes that the driver of the head vehicle issues a disbanding instruction, the vehicles in the platoon are safely separated in sequence, and the single-vehicle driving mode is restored. The emergency exiting includes that when the safety arbitration unit detects a danger, the vehicle is forced to exit the platoon, and an alarm is given to remind the driver to take over.

8. The cooperative platooning control method based on vehicle-to-vehicle communication according to claim 6, characterized by, The normal platoon strategy in the platoon driving stage includes a string-type following model, The string-type following model specifically includes role definition into a head vehicle and a following vehicle, wherein the head vehicle is the leader of the platoon, can be driven by the driver or started to automatically drive, and broadcasts its own motion state; the following vehicle is a member of the platoon, follows the cooperative control instruction, and the main communication and tracking object of each following vehicle is the directly preceding vehicle; and the string-type following model adopts a constant time distance + minimum safe distance spacing strategy, Wherein, the following distance is calculated by the following formula: D_desired = max(D_min, V*T), Wherein, D_desired represents the following distance, V represents the speed of the vehicle, T represents a preset fixed time distance, and D_min represents the minimum physical safe distance.

9. The cooperative platooning control method based on vehicle-to-vehicle communication according to claim 6, characterized by, The redundancy backup and abnormal processing strategy in the platoon driving stage includes a soft isolation and reorganization strategy in the case of communication failure of a vehicle in the platoon or vehicle itself failure, an adaptive inclusion strategy in the case of external vehicle cutting into the platoon, and a replacement head vehicle strategy in the case of abnormal exiting of the head vehicle, The soft isolation and reorganization strategy in the case of communication failure of a vehicle in the platoon or vehicle itself failure includes: If any vehicle does not receive the heartbeat signal of its directly preceding vehicle in three consecutive communication periods, it is determined that the communication with the preceding vehicle is interrupted; if the vehicle self-diagnosis system detects a key system failure and broadcasts an emergency fault code through the vehicle-to-vehicle communication module; The safety arbitration unit of the faulty vehicle is triggered, the vehicle is controlled to smoothly decelerate, and the vehicle tries to safely drive into the emergency lane; after the rear following vehicle detects the loss of communication with the preceding vehicle or receives the fault code of the faulty vehicle, the safety arbitration unit of the rear following vehicle immediately takes over the control, the control strategy is switched from cooperative following to emergency independent risk avoidance, and based on the environment perception module of the vehicle, firstly, it is ensured that no collision occurs with the faulty vehicle. Under the premise of safety, the vehicle tries to re-establish the communication link with the directly preceding vehicle. If the rear vehicle successfully connects with the front vehicle, the platoon automatically reorganizes after skipping the faulty vehicle, forms a new platoon sequence, and informs all drivers of the platoon state change and the position of the faulty vehicle through the human-machine interface; if the connection fails, the platoon is safely dispersed, and the system prompts the driver to take over, The adaptive inclusion strategy of the external vehicle cutting into the platoon includes: The environment perception module of the vehicle identifies that a vehicle cuts in between the vehicle and the directly front vehicle, and the vehicle-to-vehicle communication system of each vehicle ensures that the platoon vehicles share perception information and cross-verify; After the following vehicle detects the cutting-in vehicle, the following vehicle first shares the cutting-in information with the rear vehicle through the vehicle-to-vehicle communication module to confirm that the cutting-in behavior is stable, and after confirmation, the following vehicle regards the cutting-in vehicle as a new, non-cooperative temporary front vehicle, and the cooperative control unit of the following vehicle dynamically adjusts the following target and appropriately increases the following distance from the cutting-in vehicle to ensure safety; The entire platoon regards this event as a common disturbance, the rear vehicle continues to follow the directly front vehicle, and the entire platoon smoothly passes through this disturbance without dissolving the platoon, and if the cutting-in vehicle drives away, the platoon vehicles automatically and smoothly reduce the vehicle distance and restore to the preset optimal following state after detecting the restored space, The replacement of the head vehicle in the case of abnormal exit of the head vehicle includes: If the head vehicle voluntarily exits, the head vehicle driver issues an exit instruction, the system automatically designates the second vehicle in the platoon as a new head vehicle, and completes the leadership switch in an instant, and the original head vehicle smoothly accelerates or decelerates and changes lanes to leave the platoon; If the head vehicle suddenly fails, the head vehicle broadcasts the fault code through the vehicle-to-vehicle communication module and starts to decelerate, and after the second vehicle detects the fault code of the head vehicle, the platoon management unit of the second vehicle immediately promotes itself to the head vehicle and takes over the piloting responsibility, and controls the platoon to safely decelerate or change lanes to avoid risks.

10. The cooperative platooning control method based on vehicle-to-vehicle communication according to claim 9, characterized by, In any abnormal processing process, the safety arbitration unit follows the following highest priority principle: the safety of the vehicle first: any cooperative instruction conflicts with the emergency collision avoidance requirement determined by the local sensor, and the local determination is given priority; Gradually degrade: cooperative platoon -> independent adaptive cruise control -> emergency braking -> alarm and request the driver to take over; Information sharing: when any vehicle triggers a safety strategy, the vehicle must broadcast the dangerous information and its intention to all vehicles in the platoon through the vehicle-to-vehicle communication module to achieve cooperative warning of danger.

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