A traffic simulation method and device, electronic equipment and storage medium

Abstract

The application relates to the technical field of traffic, in particular to the technical field of automatic driving, and provides a traffic simulation method and device, an electronic device and a storage medium, so as to simultaneously improve the operation efficiency and authenticity of traffic simulation. The method comprises the following steps: determining a target lane-changing vehicle to be simulated and first driving data of a tractor in the target lane-changing vehicle; adjusting the first driving data by using a deviation adjustment coefficient based on a lane-changing time interval of each trailer, so as to obtain second driving data of each trailer; the deviation adjustment coefficient is an adjustment parameter used for the deviation phenomenon of the trailer relative to the tractor during lane changing; and updating the lane-changing trajectory of each trailer based on the second driving data. The application introduces the deviation adjustment coefficient to describe the deviation of the trailer during lane changing, and uses a relatively simple method to respectively describe the motion of the tractor and the trailer, so that the authenticity and calculation efficiency of the trajectory during lane changing are well balanced.

Description

Technical Field

[0001] This application relates to the field of transportation technology, and more particularly to the field of autonomous driving technology, providing a traffic simulation method, apparatus, electronic device, and storage medium. Background Technology

[0002] Traffic simulation is a technique that uses simulation technology to study traffic behavior. It describes the changes in traffic movement over time and space by establishing mathematical models of the real-time movement of a transportation system over a certain period. Based on the level of detail in the simulation, traffic simulation can be divided into macroscopic, mesoscopic, and microscopic traffic simulation.

[0003] In related technologies, for microscopic traffic simulation of trailers, in order to ensure simulation efficiency, the tractor and trailer in the front of the trailer are simulated by a rectangular rigid body with a length equal to the sum of the lengths of the two vehicles. That is, the movement of the trailer and the tractor is completely consistent. This makes it impossible to describe the motion characteristics of the trailer, resulting in a lack of realism.

[0004] Alternatively, to ensure the realism of the simulation as much as possible, a vehicle dynamics module can be used to model the motion of the vehicle in detail. However, for large-scale simulations involving many vehicles, this detailed modeling will frequently call the vehicle dynamics model for calculation, resulting in reduced computational efficiency and affecting the real-time performance of the simulation.

[0005] Therefore, balancing realism and simulation efficiency has become the key to the successful operation of large-scale simulations involving a large number of trailers. Summary of the Invention

[0006] This application provides a traffic simulation method, apparatus, electronic device, and storage medium to simultaneously improve the operational efficiency and realism of traffic simulation.

[0007] This application provides a traffic simulation method, including:

[0008] The target lane-changing vehicle to be simulated is determined, and the first driving data of the tractor in the target lane-changing vehicle is determined. The target lane-changing vehicle also includes at least one trailer towed by the tractor.

[0009] Based on the lane-changing time interval of each of the at least one trailer, the first driving data is adjusted by a deviation adjustment coefficient to obtain the second driving data of each of the at least one trailer; the deviation adjustment coefficient is an adjustment parameter used to address the deviation phenomenon of the trailer relative to the tractor during the lane-changing process; the lane-changing time interval is the time interval from the start to the end of the lane-changing for the corresponding trailer.

[0010] Each trailer's lane-changing trajectory is updated based on the second driving data.

[0011] This application provides a traffic simulation device, comprising:

[0012] The determining unit is used to determine the target lane-changing vehicle to be simulated, and the first driving data of the tractor in the target lane-changing vehicle. The target lane-changing vehicle also includes at least one trailer towed by the tractor.

[0013] An adjustment unit is used to adjust the first driving data based on the lane-changing time interval of each of the at least one trailer by means of a deviation adjustment coefficient, so as to obtain the second driving data of each of the at least one trailer; the deviation adjustment coefficient is an adjustment parameter used to address the deviation phenomenon of the trailer relative to the tractor during the lane-changing process, and the lane-changing time interval is the time interval corresponding to the start and end of the lane-changing for the corresponding trailer.

[0014] The update unit is used to update the lane-changing trajectory of each trailer based on each second driving data.

[0015] Optionally, the first driving data includes a first lateral velocity and a first longitudinal velocity; the second driving data includes a second lateral velocity and a second longitudinal velocity.

[0016] The adjustment unit is specifically used for:

[0017] For each trailer, perform the following operations:

[0018] The second longitudinal speed of a trailer is adjusted to the first longitudinal speed of the tractor.

[0019] If a trailer is in its corresponding lane-changing time interval, the first lateral speed of the tractor is adjusted by the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0020] Optionally, the adjustment unit is further configured to:

[0021] If a trailer is not in its corresponding lane-changing time interval, then the second lateral speed of the trailer is determined to be zero.

[0022] Optionally, the lane-changing time interval includes: a first lane-changing time sub-interval and a second lane-changing time sub-interval obtained based on a critical point; the critical point is the time when the trailer reaches its maximum lateral speed.

[0023] The adjustment unit is specifically used for:

[0024] If a trailer is in the first lane-changing time sub-interval, the first lateral speed is decelerated and adjusted based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0025] If a trailer is in the second lane-changing time sub-interval, the first lateral speed is adjusted to increase the speed based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0026] Optionally, the adjustment unit is specifically used for:

[0027] The difference between the preset parameter and the deviation adjustment coefficient is used as the deceleration coefficient; the preset parameter is greater than the deviation adjustment coefficient.

[0028] Based on the aforementioned tractor at tT d The first lateral velocity at time t, together with the deceleration coefficient, determines the second lateral velocity of the trailer at time t, where t is the current time and T is the deceleration coefficient. d The lateral lag time is the time that the trailer lags behind the tractor in generating lateral speed.

[0029] Optionally, the adjustment unit is specifically used for:

[0030] The sum of the preset parameter and the deviation adjustment coefficient is used as the growth coefficient; the preset parameter is greater than the deviation adjustment coefficient.

[0031] Based on the aforementioned tractor at tT d The first lateral velocity at time t, together with the growth coefficient, determines the second lateral velocity of the trailer at time t, where t is the current time and T is the speed of the trailer. d The lateral lag time is the time that the trailer lags behind the tractor in generating lateral speed.

[0032] Optionally, the adjustment unit is further configured to determine the lane-changing time interval corresponding to each trailer in the following manner:

[0033] Obtain the lane-changing duration and lane-changing start time corresponding to the tractor;

[0034] Based on the lane change duration and the lane change start time, the corresponding lane change end time is determined;

[0035] Based on the lateral lag time corresponding to a trailer and the start time of the lane change, the left boundary of the lane change time interval is determined, and based on the lateral lag time corresponding to a trailer and the end time of the lane change, the right boundary of the lane change time interval is determined; the lateral lag time is the lag time of the trailer relative to the tractor in generating lateral speed.

[0036] Optionally, the lateral lag time is determined based on the inherent characteristics of the target lane-changing vehicle; for a trailer, the corresponding lateral lag time of the trailer is positively correlated with the distance between the trailer and the tractor.

[0037] Optionally, the first driving data includes a first lateral velocity and a first longitudinal velocity;

[0038] The determining unit is specifically used to determine the first driving data of the tractor in the following ways:

[0039] Based on the third driving data of the vehicle preceding the target lane-changing vehicle in the same lane, and the distance between the preceding vehicle and the target lane-changing vehicle, the first longitudinal speed of the tractor is determined; the same lane is either the current lane before lane changing or the target lane after lane changing.

[0040] Based on the lane change duration and lane change distance, the first lateral speed of the tractor is determined, whereby the lane change distance is the lateral distance that the target lane-changing vehicle needs to traverse during the process of changing from the current lane to the target lane.

[0041] Optionally, the deviation adjustment coefficient is determined by any of the following methods:

[0042] Obtain the pre-set deviation adjustment coefficient;

[0043] The deviation adjustment coefficient is determined based on the inherent characteristics of the target lane-changing vehicle.

[0044] Optionally, the second driving data includes a second lateral speed and a second longitudinal speed;

[0045] The update unit is specifically used for:

[0046] Perform the following operations for each trailer:

[0047] For a trailer, the second lateral velocity and the second longitudinal velocity of the trailer are vectored together to determine the heading angle of the trailer;

[0048] Based on the heading angle, the driving posture of the trailer is adjusted, and the lane-changing trajectory of the trailer is updated based on the adjustment result.

[0049] An electronic device provided in this application includes a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of any of the traffic simulation methods described above.

[0050] This application provides a computer-readable storage medium including a computer program. When the computer program is run on an electronic device, the computer program is used to cause the electronic device to perform the steps of any of the above-described traffic simulation methods.

[0051] This application provides a computer program product, which includes a computer program stored in a computer-readable storage medium. When the processor of an electronic device reads the computer program from the computer-readable storage medium, the processor executes the computer program, causing the electronic device to perform the steps of any of the above-described traffic simulation methods.

[0052] The beneficial effects of this application are as follows:

[0053] This application provides a traffic simulation method, apparatus, electronic device, and storage medium. Because this application defines the tractor and trailer as two independent objects and describes the longitudinal and lateral movements of the trailer separately, it introduces a deviation adjustment coefficient to describe the trailer's deviation during lane changes. Furthermore, the description of trailer deviation only requires adjusting the tractor's driving data based on the deviation adjustment coefficient, eliminating the need to construct a detailed dynamic model. This relatively simple approach to describing the motion of the tractor and trailer effectively balances the realism of the trajectory during lane changes with computational efficiency, resulting in a more realistic simulation of the trailer while simplifying computation.

[0054] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0055] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0056] Figure 1 This is an optional schematic diagram of an application scenario in an embodiment of this application;

[0057] Figure 2 This is a flowchart illustrating a traffic simulation method in an embodiment of this application;

[0058] Figure 3 This is a schematic diagram of the motion posture of a semi-trailer truck in an embodiment of this application;

[0059] Figure 4 This is a schematic diagram of car following and lane changing in a microscopic traffic simulation according to an embodiment of this application;

[0060] Figure 5 This is a schematic diagram illustrating a low-speed deviation phenomenon in an embodiment of this application.

[0061] Figure 6 This is a schematic diagram illustrating a high-speed deviation phenomenon in an embodiment of this application;

[0062] Figure 7 This is a schematic diagram of the lane-changing trajectory of a trailer in an embodiment of this application;

[0063] Figure 8 This is a schematic diagram of a trailer vehicle according to an embodiment of this application;

[0064] Figure 9 This is a schematic diagram of the heading angle of a trailer in one embodiment of this application;

[0065] Figure 10 This is a schematic diagram illustrating the lateral speed adjustment of a trailer in an embodiment of this application;

[0066] Figure 11 This is a schematic diagram illustrating the lateral positional relationship of a trailer in an embodiment of this application;

[0067] Figure 12 This is a flowchart illustrating the update speed of a trailer in one embodiment of this application;

[0068] Figure 13 This is a schematic diagram of the composition structure of a traffic simulation device according to an embodiment of this application;

[0069] Figure 14 This is a schematic diagram of the hardware structure of an electronic device using an embodiment of this application;

[0070] Figure 15 This is a schematic diagram of the hardware structure of a computing device according to an embodiment of this application. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this application. Obviously, the described embodiments are only some embodiments of the technical solutions of this application, and not all embodiments. Based on the embodiments recorded in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the technical solutions of this application.

[0072] The following describes some of the concepts involved in the embodiments of this application.

[0073] Tractor and Trailer: A trailer is a truck that combines one or more vehicle bodies to transport goods. The tractor unit (also called the trailer) with driving capability at the front is called the tractor (or trailer), and the trailer without driving capability at the rear is called the trailer. The trailer is towed by the tractor. There are two ways to connect the tractor and trailer: The first is that the front half of the trailer rests on the towing saddle on the rear section of the tractor, and the rear axle of the tractor bears part of the trailer's weight; this is a semi-trailer. The second is that the front end of the trailer is connected to the rear end of the tractor, and the tractor only provides forward pulling force, towing the trailer but not bearing the trailer's downward weight; this is a full trailer. The most obvious difference between a full trailer and a semi-trailer is that a full trailer can stand independently, while a semi-trailer must rely on outriggers to stand. Common container trucks are typical semi-trailer trucks, with the semi-trailer being the cargo section at the rear.

[0074] Driving data: Data used to describe the vehicle's driving process and driving status, such as acceleration, speed, position, heading angle, etc. When the vehicle is not traveling in a straight line (such as changing lanes or turning), the speed can be further divided into: lateral speed and longitudinal speed. Lateral speed refers to the direction perpendicular to the vehicle's driving direction, while longitudinal speed refers to the direction of the vehicle's driving direction.

[0075] Trailing deviation: This refers to the phenomenon where the trailer deviates from the trajectory of the tractor unit. The yaw rate and lateral velocity of the tractor unit increase with the transmission at the articulation point, which means that the lateral movement amplitude of the trailer may be greater than that of the tractor unit. At the same time, when the lateral velocity of the trailer and trailer changes (such as changing lanes), trailing deviation (off-tracking) will occur. That is, when the tractor unit is not traveling in a straight line (such as changing lanes or turning), the trajectory of the trailer will be different from that of the tractor unit.

[0076] Lane drift adjustment coefficient: An adjustment parameter used during lane changing to address the lane drift phenomenon caused by the trailer relative to the tractor. Based on this lane drift adjustment coefficient, the lateral displacement of the trailer can be adjusted to ensure that, at the same time, the lateral position of the trailer is always closer to its original position before lane changing than that of the tractor.

[0077] Lateral lag time: This refers to the time lag between the trailer and the tractor unit in generating lateral velocity when a vehicle changes lanes. Since the tractor unit provides power, it generates lateral velocity first. The trailer, lacking independent power, only generates lateral velocity T after the tractor unit has generated lateral velocity. d It takes seconds for lateral velocity to begin to form; this lag time is defined here as T. d This is the horizontal lag time.

[0078] Lane change duration: refers to the time elapsed from the start of a lane change to the completion of the lane change, that is, the duration of the period during which the lateral speed is not zero, such as the time required to change from the center line of the current lane to the center line of the target lane.

[0079] Lane change time interval: The process of a vehicle changing lanes from its current lane to its target lane is a continuous process, and the time period corresponding to this process is a time interval, which is the lane change time interval for that vehicle. For trailers, the lane change time interval for each trailer refers to the time interval from the start of the lane change to the end of the lane change. For example, if a trailer starts changing lanes at time T1 and ends at time T2, then the lane change time interval for that trailer is [T1, T2].

[0080] Vehicle inherent characteristics refer to the attributes inherent in a vehicle, such as vehicle type, body weight, vehicle model, performance, and length. For trailers, which include both a tractor and trailer, vehicle type includes, but is not limited to, tractor and trailer models; body weight includes, but is not limited to, tractor weight, trailer weight, and total weight of the trailer; and vehicle model, performance, and length follow a similar logic. Furthermore, there are articulation points between the tractor and trailer, and when a trailer contains multiple trailers, there may also be articulation points between the trailers. The characteristics of these articulation points also fall under the category of vehicle inherent characteristics.

[0081] Car-following theory, also known as car-following algorithm, is a theory that uses dynamics to explore the driving state of a following vehicle when vehicles are traveling in a convoy on a single lane where overtaking is not possible. It is expressed and analyzed using mathematical models.

[0082] Artificial intelligence (AI) is the theory, methods, technology, and application systems that use digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to achieve optimal results. In other words, AI is a comprehensive technology within computer science that attempts to understand the essence of intelligence and produce a new kind of intelligent machine that can react in a way similar to human intelligence. AI studies the design principles and implementation methods of various intelligent machines, enabling them to possess the functions of perception, reasoning, and decision-making.

[0083] With the research and advancement of artificial intelligence (AI) technology, AI is being studied and applied in various fields, such as smart homes, smart wearable devices, virtual assistants, smart speakers, smart marketing, autonomous driving, drones, robots, smart healthcare, smart customer service, and smart video services. As the technology develops, AI will be applied in more fields and play an increasingly important role.

[0084] Autonomous driving technology typically includes high-precision maps, environmental perception, behavioral decision-making, path planning, and motion control, and has broad application prospects. Furthermore, the development of autonomous driving systems requires a process from simulation to real-vehicle testing. Simulation experiments based on autonomous driving simulation systems, as a zero-risk, rapid-iteration, and reproducible testing method, lay a solid foundation for the deployment of autonomous driving on public roads.

[0085] The traffic simulation method provided in this application can be applied to fields such as maps, navigation, autonomous driving, intelligent vehicle control, vehicle networking, intelligent transportation, and cloud computing. For example, it can be applied to intelligent traffic systems (ITS) and intelligent vehicle infrastructure cooperative systems (IVICS) in the transportation field.

[0086] Intelligent Transportation Systems (ITS), also known as Intelligent Transportation Systems, effectively integrate advanced technologies (information technology, computer technology, data communication technology, sensor technology, electronic control technology, automatic control theory, operations research, artificial intelligence, etc.) into transportation, service control, and vehicle manufacturing. This strengthens the connection between vehicles, roads, and users, thereby forming a comprehensive transportation system that ensures safety, improves efficiency, enhances the environment, and conserves energy. Based on the traffic simulation method provided in this application, microscopic traffic simulation of trailers can be performed efficiently and accurately.

[0087] Among them, the intelligent vehicle-road cooperative system, or vehicle-road cooperative system for short, is a development direction of intelligent transportation systems (ITS). The vehicle-road cooperative system utilizes advanced wireless communication and next-generation Internet technologies to implement comprehensive, dynamic, real-time information interaction between vehicles and roads. Based on the collection and fusion of dynamic traffic information across all times and spaces, it conducts active vehicle safety control and cooperative road management, fully realizing effective coordination between people, vehicles, and roads, ensuring traffic safety, improving traffic efficiency, and thus forming a safe, efficient, and environmentally friendly road traffic system. The traffic simulation method provided in the embodiments of this application can provide technical support for traffic safety and vehicle-road cooperation.

[0088] The design concept of the embodiments of this application is briefly introduced below:

[0089] Simulation technology is a simulation modeling technology that uses simulation hardware and software to reflect the behavior or process of a system through simulation experiments, with the help of certain numerical calculations and problem solving.

[0090] Traffic simulation is an important tool for studying complex traffic problems, especially when a system is too complex to be described by a simple, abstract mathematical model. The purpose of traffic simulation is to reproduce or predict the traffic operation of a relevant or future system, thereby explaining and analyzing complex traffic phenomena, identifying the root causes of problems, and ultimately optimizing the studied traffic system. The goal is to create a model that accurately reflects the actual operation of a real traffic system, realistically simulating various actual traffic behaviors in a real road network. Examples include pre-trip planning and decision-making, vehicle following during travel, lane changes, overtaking, and route changes caused by intersection signal delays. Traffic policies can clearly assist in analyzing and predicting traffic congestion locations and causes, comparing and evaluating relevant urban planning, traffic engineering, and traffic management solutions, and preventing or preparing for problems before they materialize.

[0091] Microscopic traffic simulation provides the highest level of detail in describing the elements and behaviors of traffic systems. For example, microscopic traffic simulation models describe traffic flow using individual vehicles as the basic unit, and can realistically reflect the microscopic behaviors of vehicles on the road, such as following, overtaking, and lane changing.

[0092] In related microscopic traffic simulations, either the tractor and trailer are described as a single rigid body, resulting in a loss of realism, or vehicle dynamics models are used to describe their motion separately, reducing computational efficiency. Therefore, balancing realism and simulation efficiency has become crucial for the successful operation of large-scale simulations involving numerous trailers.

[0093] In view of this, embodiments of this application propose a traffic simulation method, device, electronic device, and storage medium. Because this application defines the tractor and trailer as two independent objects and describes the longitudinal and lateral movements of the trailer separately, it introduces a deviation adjustment coefficient to describe the trailer's deviation during lane changes. Furthermore, the description of trailer deviation only requires adjusting the tractor's driving data based on the deviation adjustment coefficient, eliminating the need to construct a detailed dynamic model. This relatively simple approach to describing the motion of the tractor and trailer effectively balances the realism of the trajectory during lane changes with computational efficiency, resulting in a more realistic simulation effect for the trailer while simplifying computation.

[0094] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application. Furthermore, the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0095] like Figure 1 The diagram shown is an application scenario illustration of an embodiment of this application. The application scenario diagram includes two terminal devices 110 and one server 120.

[0096] In this embodiment, the terminal device 110 includes, but is not limited to, mobile phones, tablets, laptops, desktop computers, e-book readers, smart voice interaction devices, smart home appliances, and in-vehicle terminals. The terminal device may have a traffic simulation-related client installed. This client can be software (such as a browser, simulation software, etc.), or a webpage, mini-program, etc. The server 120 is the backend server corresponding to the software, webpage, mini-program, etc., or a server specifically used for traffic simulation; this application does not impose specific limitations. The server 120 can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDN), and big data and artificial intelligence platforms.

[0097] It should be noted that the traffic simulation method in each embodiment of this application can be executed by an electronic device, which can be a terminal device 110 or a server 120. That is, the method can be executed by the terminal device 110 or the server 120 alone, or by both the terminal device 110 and the server 120. For example, when executed by the terminal device 110 alone, simulation software can be installed on the terminal device 110. This simulation software can be a microscopic traffic simulation software. The logic algorithm involved in the traffic simulation method of this application is embedded in the simulation software to realize the traffic simulation of controlling the target lane-changing vehicle according to the logic algorithm through the simulation software, and the simulation results are displayed through a simulation result display window. Specifically, the simulation results can be displayed in text form (such as lane-changing trajectory), or the simulation results can be simulated and displayed in animation form, etc.

[0098] Alternatively, when executed independently by server 120, server 120 can directly control the traffic simulation of the target lane-changing vehicles according to the logic algorithm involved in the traffic simulation method of this application, and obtain the final simulation result. In addition, server 120 can also send the simulation result to terminal device 110 for display, and so on.

[0099] The simulation software installed on the terminal device 110 can be the microscopic simulation software TAD Sim. For example, the logic algorithm involved in the traffic simulation method of this application can be embedded in the microscopic simulation software TAD Sim to simulate the behavior of traffic vehicles with trailers. In each simulation step, when it is necessary to update the speed of the trailer, the method of this application is used to describe the lateral and longitudinal motion of the trailer.

[0100] In one alternative implementation, the terminal device 110 and the server 120 can communicate via a communication network.

[0101] In one alternative implementation, the communication network is a wired network or a wireless network.

[0102] It should be noted that, Figure 1 The examples shown are merely illustrative; in reality, the number of terminal devices and servers is unlimited and is not specifically limited in the embodiments of this application.

[0103] In this embodiment of the application, when there are multiple servers, the multiple servers can form a blockchain, and the server is a node on the blockchain; as disclosed in the traffic simulation method of this application, the simulation data involved can be stored on the blockchain, such as driving data, deviation adjustment coefficient, etc.

[0104] Furthermore, the embodiments of this application can be applied to various scenarios, including but not limited to cloud technology, artificial intelligence, smart transportation, and assisted driving.

[0105] The traffic simulation method provided by the exemplary embodiments of this application will be described below with reference to the accompanying drawings and the application scenarios described above. It should be noted that the application scenarios described above are only shown to facilitate understanding of the spirit and principles of this application, and the embodiments of this application are not limited in any way in this respect.

[0106] See Figure 2 The diagram shown is a flowchart of a traffic simulation method provided in this application. Taking the server as the execution entity as an example, the specific implementation process of this method is as follows (S21-S23):

[0107] S21: The server determines the target lane-changing vehicle to be simulated, and the first driving data of the tractor unit in the target lane-changing vehicle. The target lane-changing vehicle also includes at least one trailer towed by the tractor unit.

[0108] In related technologies, microscopic traffic simulations generally treat the body of small vehicles as a rigid body (approximately a cuboid). When calculating lateral and longitudinal velocities and accelerations, it can be considered as a point mass, meaning that any part of the vehicle body moves in a consistent manner without deformation. However, in a trailer, the tractor and trailer are connected by hooks or tow pins. When lateral velocities exist (such as during lane changes), their motion postures differ, such as... Figure 3 As shown, it is a schematic diagram of the motion posture of a semi-trailer truck in an embodiment of this application. Obviously, when turning and changing lanes, the motion posture of the tractor and the trailer is different. If the tractor and the trailer are still described as a rigid body, the realism will be lost.

[0109] Therefore, in this application, the tractor and trailer are considered as different rigid bodies. For example, a trailer consisting of only one tractor and one trailer can be represented by two cuboid rigid bodies containing the outer contours of the tractor and trailer, respectively. A trailer consisting of one tractor and multiple trailers can be represented by multiple cuboid rigid bodies containing the outer contours of the tractor and each trailer, respectively. Furthermore, this application temporarily does not consider the case of trailers being towed by ropes (such as a non-specialized vehicle towing a disabled vehicle with a rope).

[0110] The target lane-changing vehicle consists of a tractor unit and at least one trailer. Since the tractor unit and trailer are considered as different rigid bodies in this application, for ease of description, the driving data of the tractor unit will be referred to as the first driving data, and the driving data of the trailer will be referred to as the second driving data.

[0111] It should be noted that the driving data in this application embodiment is data used to describe the vehicle's driving process, driving status, etc., including but not limited to the vehicle's speed, acceleration, position, heading angle, etc. during the driving process.

[0112] The following detailed explanation mainly focuses on driving data including speed. When the driving data includes other data besides speed, the traffic policy method in this application embodiment is also applicable, and will not be elaborated on here.

[0113] One possible implementation is that the first driving data includes a first lateral speed and a first longitudinal speed; wherein the lateral speed refers to the direction perpendicular to the direction of travel of the target lane-changing vehicle, and the longitudinal speed refers to the direction of travel of the target lane-changing vehicle.

[0114] Optionally, for the tractor unit among the target lane-changing vehicles, the first longitudinal speed of the tractor unit can be determined in the following manner:

[0115] Based on the third driving data of the vehicle preceding the target lane-changing vehicle in the same lane, and the distance between the preceding vehicle and the target lane-changing vehicle, the first longitudinal speed of the tractor is determined; the same lane is either the current lane before the lane change or the target lane after the lane change.

[0116] like Figure 4 As shown, it is a schematic diagram of car following and lane changing in a microscopic traffic simulation according to an embodiment of this application.

[0117] In this application, the longitudinal micro-driving behavior of the tractor unit can be determined by a car-following algorithm. That is, within each simulation step, the tractor unit updates its longitudinal acceleration, speed, and position based on the speed of the vehicle ahead in the same lane and the distance between the preceding vehicle and the tractor unit. The following explanation uses the updating of longitudinal speed as an example:

[0118] exist Figure 4 In the context of the target lane-changing vehicle E (including tractor-trailers and trailers), Figure 4 (This is just a simple example.) The vehicle needs to change lanes from its current lane to the target lane. In the current lane, the vehicle in front of it is P, and the distance between the vehicle in front of P and the vehicle itself (i.e., the target vehicle E) is G. P On the target lane, the vehicle in front is TP, and the distance between the vehicle in front of TP and the vehicle in the target lane is G. TP The following vehicle is TR, and the distance between the vehicle in front (TR) and this vehicle in the target lane is G. TR .

[0119] It should be noted that, assuming the target lane-changing vehicle E intends to change lanes, the distance G between it and the vehicle in front in the target lane... TP Distance G to the car behind TR All distances should be greater than a certain preset safety distance. Lane changing operations can only be performed when safety conditions are met.

[0120] In this embodiment of the application, when updating the longitudinal speed of the vehicle based on the speed of the vehicle in front in the same direction lane and the distance between the vehicle in front and the vehicle in front, considering that the same direction lane of the target lane-changing vehicle will change during the lane-changing process, in order to simplify the process, the entire lane-changing process can be divided into two equal parts: the first half of the entire lane-changing process is divided into the first half, and the second half of the entire lane-changing process is divided into the second half. Based on this, the same direction lane can be determined in the following way:

[0121] In the first half of the lane change where the target vehicle moves from the current lane to the target lane, the current lane is taken as the same-direction lane, and the corresponding preceding vehicle is the preceding vehicle P in the current lane. Therefore, the speed V of the preceding vehicle P can be used as a reference. P and the corresponding vehicle distance G P To determine the longitudinal velocity V of the target lane-changing vehicle E. E When a vehicle changes lanes from its current lane to the target lane in the latter half of its journey, the target lane is taken as the same-direction lane, and the corresponding preceding vehicle is designated as the preceding vehicle TP in the target lane. Therefore, the speed V of the preceding vehicle TP can be used as a basis for determining the direction of travel. TP and the corresponding vehicle distance G TP To determine the longitudinal velocity V of the target lane-changing vehicle E. E .

[0122] It should be noted that the above method of dividing the lane-changing process is only a simplified explanation. The specific method of division can also be determined according to the actual situation. For example, the time when the tractor of the target lane-changing vehicle E crosses the boundary line between the current lane and the target lane can be used as the dividing point to divide the entire lane-changing process into the first half and the second half, etc. This article does not make specific limitations.

[0123] Optionally, for the tractor unit among the target lane-changing vehicles, the first lateral speed of the tractor unit can be determined in the following way:

[0124] The first lateral speed of the tractor is determined based on the lane change duration and lane change distance.

[0125] The lane change duration refers to the time elapsed from the start of the lane change to the completion of the lane change when the target lane-changing vehicle changes lanes. It is the duration of the time when the lateral speed is not zero, such as the time required to change from the center line of the current lane to the center line of the target lane.

[0126] Lane change distance is the lateral distance that a vehicle needs to traverse when changing lanes from its current lane to its target lane. Specifically, it refers to the lateral distance that the target vehicle needs to traverse from the start of the lane change to the completion of the lane change, such as the lateral distance between the center lines of the current lane and the center lines of the target lane when changing from the center line of the current lane to the center line of the target lane.

[0127] Specifically, in the embodiments of this application, the lateral velocity can be determined by combining higher-order polynomials, such as by determining the coefficients of a fifth-order polynomial, and then determining the lateral velocity, acceleration, and position at each moment during the lane change process.

[0128] Assume that the initial time T of the lane change is... a =0, use (Q) d0 V d0 A d0 Let (Q) describe the lateral position, velocity, and acceleration at time t=0, with the lane change duration being T. dT V dT A dT The lateral position, velocity, and acceleration at time t=T are described by , and h (usually the lane width) represents the distance from the original lane centerline to the target lane centerline. Correspondingly, V... d0 =V dT =0, A d0 =A dT =0, Q d0 =0, Q dT =h.

[0129] There are a total of six boundary conditions. Correspondingly, a fifth-order polynomial can be used to describe the vehicle's position Q in the lateral direction at any time t. d =a0+a1t+a2t 2 +a3t 3 +a4t 4 +a5t 5 Based on V d0 =V dT =0, A d0 =A dT =0, Q d0 =0, Q dT =h can be used to solve for the polynomial coefficients a0, a1, a2, a3, a4 and a5.

[0130] a0 = Q d0 ;

[0131] a1=V d0 ;

[0132] a2 = 0.5a0;

[0133] a3=1 / 2T 3 [20h-(8V dT +12V d0 )T-(3a0-a1)T 2 ;

[0134] a4=1 / 2T 4 -30h-(14V) dT +16Vd0 )T+(3a0-2a1)T 2 ;

[0135] a5 = 1 / 2T 5 [12h-6(V dT +V d0 )T+(a1-a0)T 2 .

[0136] After obtaining the polynomial coefficients a0, a1, a2, a3, a4, and a5, the lateral position of the target lane-changing vehicle at each moment can be determined. Furthermore, based on the lateral position during the lane-changing process and the lateral velocity in the initial lateral travel data and the preset end lateral travel data, the lateral velocity at each moment during the lane-changing process can be determined.

[0137] It should be noted that the methods for determining the lateral speed of the tractor by combining a fifth-order polynomial as described in the above embodiments are merely illustrative examples. Any method combining a higher-order polynomial is applicable to the embodiments of this application, and no specific limitation is made herein.

[0138] In this embodiment of the application, when the tractor considers rule-based lane changing, it will take into account the length of the trailer and its own tractor (i.e., the total vehicle length) and judge the lane changing conditions such as the safety distance. If all conditions are met, it will start the lane changing process, that is, calculate the coefficients of the fifth-order polynomial according to the lane changing duration and the distance crossed by the lane changing, and update the lateral speed.

[0139] Once the driving data of the tractor unit is determined, the driving data of each trailer towed by the tractor unit can be determined by referring to the driving data of the tractor unit.

[0140] S22: The server adjusts the first driving data based on the lane-changing time interval of at least one trailer by using a deviation adjustment coefficient to obtain the second driving data of at least one trailer.

[0141] The deviation adjustment coefficient is an adjustment parameter used during lane changing to address the deviation of the trailer relative to the tractor. This deviation adjustment coefficient is non-negative, meaning it can be 0, or a parameter greater than 0 and less than a preset parameter. For example, if the preset parameter is 1, the deviation adjustment coefficient is greater than or equal to 0 and less than 1. Similarly, if the preset parameter is 1.01, the deviation adjustment coefficient is greater than or equal to 0 and less than 1.01; and if the preset parameter is 0.99, the deviation adjustment coefficient is greater than or equal to 0 and less than 0.99. It should be noted that the preset parameter in this embodiment is 1 or a parameter close to 1.

[0142] The following is a detailed explanation of the aforementioned deviation phenomenon:

[0143] Specifically, the study found that the yaw rate and lateral velocity of the tractor increase with the transmission at the articulation point, which means that the lateral motion amplitude of the trailer may be greater than that of the tractor. At the same time, the trailer will experience off-tracking when there is a change in lateral velocity (such as changing lanes), that is, when the tractor is not traveling in a straight line (such as changing lanes or turning), the trajectory of the trailer is different from that of the tractor.

[0144] See Figure 5 The diagram shown illustrates a low-speed lane-hopping phenomenon in an embodiment of this application. The target lane-changing vehicle is a trailer truck. When the trailer truck is traveling at a low speed, such as 8 km / h, its trajectory (dashed line) is inside the trajectory (solid line) of the tractor truck.

[0145] See Figure 6 The diagram shown illustrates a high-speed vehicle drift phenomenon in an embodiment of this application. When the trailer travels at a high speed, such as 100 km / h, the trailer's trajectory (dashed line) is outside the tractor's trajectory (solid line).

[0146] In this embodiment of the application, the deviation adjustment coefficient can be determined in any of the following ways:

[0147] Method 1: Obtain the pre-set deviation adjustment coefficient.

[0148] For example, a uniform coefficient preset by the user can be used as the deviation adjustment coefficient for all trailers, such as 0.5.

[0149] Method 2: Determine the deviation adjustment coefficient based on the inherent characteristics of the target lane-changing vehicle.

[0150] The inherent characteristics of a vehicle refer to its inherent attributes, such as vehicle type, body weight, vehicle model, performance, and length. For a trailer, which includes both a tractor and a trailer, the vehicle type includes, but is not limited to, the tractor and trailer models; the body weight includes, but is not limited to, the tractor weight, trailer weight, and the total weight of the trailer; and the vehicle model, performance, and length follow a similar logic. Furthermore, there are articulation points between the tractor and trailer, and when a trailer contains multiple trailers, there may also be articulation points between the trailers. The characteristics of these articulation points also fall under the category of inherent vehicle characteristics.

[0151] For example, the drift adjustment coefficient can be determined based on the vehicle model, performance, weight, etc. A heavier vehicle corresponds to a smaller drift adjustment coefficient, or better vehicle performance corresponds to a smaller drift adjustment coefficient, and so on.

[0152] Furthermore, when lateral offset adjustment is not considered, this coefficient can be set to 0. That is, when the deviation adjustment coefficient is 0, it means that deviation is not considered, and only the first driving data corresponding to the tractor needs to be adjusted based on the lane-changing time interval corresponding to the trailer (which can also be understood as the corresponding lateral lag time) to obtain the second driving data corresponding to the trailer.

[0153] It should be noted that the above method of determining the drift adjustment coefficient based on the inherent characteristics of the vehicle is only an example. This article does not limit the specific form and calculation of the drift adjustment coefficient. Any method of determining the drift adjustment coefficient is applicable to the embodiments of this application.

[0154] consider Figure 5 and Figure 6 The observed lane drift phenomenon generally occurs because the lateral speed of a vehicle changing lanes is not very high. Therefore, the lateral movement trajectory of the trailer can be considered only at low speeds, meaning that at low speeds, the lateral movement trajectory of the trailer is within the trajectory of the tractor. To account for this phenomenon, this application introduces a floating-point lane drift adjustment coefficient α between (0, 1), which is applied to the lateral speed of the trailer to keep the trailer's trajectory within the tractor's trajectory, while ensuring that the lateral movement distance is still the difference between the centerline distance of the target lane and the current lane (also known as the original lane) (or the lane width if the lane widths are the same).

[0155] Furthermore, this application also takes into account that when a vehicle changes lanes, since the tractor unit provides the power, the tractor unit in front will first generate a lateral velocity V. x0 (i.e., the first lateral velocity), since the trailer has no independent power, it only has T after the tractor generates lateral velocity. d It takes seconds for lateral velocity to begin to form; this lag time T is defined in this application. d This is the lateral lag time, which is the time it takes for a trailer to lag behind the tractor in generating lateral speed.

[0156] See Figure 7 As shown, this is a schematic diagram of the lane-changing trajectory of a trailer in an embodiment of this application. Combining the aforementioned lateral velocity lag, the lane-changing trajectory ("S"-shaped curve) of the rigid body point of the trailer can be derived as follows: Figure 7 As shown, the trailer's trajectory is the same as the tractor's, but the trailer lags behind the tractor in lateral speed by T. d time.

[0157] Optionally, the lateral lag time can also be determined based on the inherent characteristics of the target lane-changing vehicle. This can be related to factors such as vehicle type, vehicle weight, and articulation points. Vehicle type includes, but is not limited to, the type of tractor unit and trailer unit; vehicle weight includes, but is not limited to, the weight of the tractor unit, the weight of the trailer, the total weight of the tractor unit and trailer, and the total weight of multiple trailers; articulation points include, but are not limited to, the articulation points between the tractor unit and trailer, and the articulation points between trailers. For example, a greater trailer weight corresponds to a greater lateral lag time, and a longer trailer length also corresponds to a greater lateral lag time, and so on.

[0158] Furthermore, when the target lane-changing vehicle comprises multiple trailers, the lateral lag time for each trailer is positively correlated with the distance between the trailer and the tractor unit. That is, the greater the distance between a trailer and the tractor unit towing it, the greater the lateral lag time for that trailer; conversely, the closer the distance, the smaller the lateral lag time.

[0159] For example, if a tractor unit has multiple trailers attached longitudinally behind it, such as Figure 8 As shown, this is a schematic diagram of a trailer according to an embodiment of this application. The trailer includes a tractor unit and multiple trailers longitudinally attached to the tractor unit in sequence. The lateral lag time of each trailer is different, such as the first trailer lagging by 1 second, the second trailer lagging by 1.6 seconds, etc.

[0160] It should be noted that the determination of the lateral lag time listed above is only an example. Any method of determining the lateral lag time is applicable to the embodiments of this application, and will not be described in detail here.

[0161] In this embodiment, since each trailer has its own lateral lag time relative to the tractor, the start time of lane changing for each trailer is different, and the end time of lane changing is also different. Therefore, each trailer has its own corresponding lane changing time interval. Specifically, the lane changing time interval corresponding to each trailer refers to the time interval from the start to the end of lane changing for the corresponding trailer; for example, if a trailer starts lane changing at time T1 and ends lane changing at time T2, then the lane changing time interval corresponding to that trailer is [T1, T2].

[0162] In one alternative implementation, the lane-changing time interval for each trailer is determined in the following way:

[0163] First, obtain the lane-changing duration corresponding to the tractor, as well as the lane-changing start time, such as the pre-configured lane-changing duration T and lane-changing start time T. a Furthermore, based on the lane change duration and the lane change start time, the corresponding lane change end time T can be determined. b (T b=T a +T); The lane change start and end times determined here are for the tractor unit. Based on the above, each trailer will have a certain lateral lag time relative to the tractor unit. Therefore, when determining the lane change time interval for a trailer, it is necessary to determine the left boundary of the lane change time interval based on the trailer's corresponding lateral lag time and lane change start time. That is, the left boundary is T. a +T d Based on the lateral lag time corresponding to the trailer and the end time of the lane change, the right boundary of the lane change time interval is determined, that is, the right boundary is T. b +T d .

[0164] When the target lane-changing vehicle includes multiple trailers, the lateral lag time T for each trailer is different. d Because of these differences, their corresponding lane-changing time intervals are also different.

[0165] S23: The server updates the lane-changing trajectory of each trailer based on the second driving data.

[0166] In this embodiment of the application, after obtaining the driving data (i.e., the second driving data) of each trailer based on the above method, the lane-changing trajectory of the corresponding trailer can be simulated.

[0167] One optional implementation involves updating the lane-changing trajectory based on the second speed data, where the second driving data includes a second lateral speed and a second longitudinal speed. Specifically, the following operations are performed for each trailer:

[0168] For a trailer, the second lateral velocity and the second longitudinal velocity of the trailer are vectorized to determine the heading angle of the trailer; then, based on the heading angle, the driving attitude of the trailer is adjusted, and the lane-changing trajectory of the trailer is updated based on the adjustment result.

[0169] In this application, the microscopic traffic simulation of trailers treats the tractor as a rectangular rigid body and each trailer as a rectangular rigid body. After the longitudinal and lateral velocities of the trailers are updated, the orientation angle of the rectangular rigid body representing the trailer (i.e., the heading angle of the trailer) is determined by vector synthesis based on the longitudinal and lateral velocities.

[0170] like Figure 9 As shown, this is a schematic diagram of the heading angle of a trailer in an embodiment of this application. Figure 9 This example illustrates the process of determining the trailer's heading angle by vector synthesis of lateral and longitudinal velocities, where the trailer's second lateral velocity is V. x1 The second longitudinal velocity is Vy1 , Figure 9 The rectangular rigid body in the diagram represents the trailer.

[0171] In this embodiment of the application, after adjusting the driving posture of the trailer in the above manner, the lane-changing trajectory of the trailer can be updated on this basis.

[0172] It should be noted that the above is only an example of a trailer containing one trailer. When there are multiple trailers, each trailer can be regarded as a rigid body. The specific update method is similar to the above process, and the repeated parts will not be repeated.

[0173] Furthermore, the traffic simulation process can be iterative, meaning it is updated at regular intervals, with each iteration corresponding to a simulation step size. The simulation step size represents the duration of one simulation iteration.

[0174] The traffic simulation method in this application embodiment can also characterize the update process in a single iteration, such as determining the target lane-changing vehicle to be simulated at the current simulation step length, and the first driving data of the tractor in the target lane-changing vehicle at the current simulation step length; then, based on the lane-changing time interval of at least one trailer, the first driving data is adjusted by the deviation adjustment coefficient to obtain the second driving data of at least one trailer at the current simulation step length; finally, based on each of the second driving data, the lane-changing trajectory of each trailer at the current simulation step length is updated.

[0175] In this embodiment, the tractor and trailer are defined as two independent objects, and the longitudinal and lateral movements of the trailer are described separately. A deviation adjustment coefficient is introduced to describe the deviation of the trailer during lane changes. The description of trailer deviation only needs to be obtained by adjusting the driving data of the tractor based on the deviation adjustment coefficient, without the need to build a detailed dynamic model. The movement of the tractor and trailer is described in a relatively simple way, which well balances the realism of the trajectory during lane changes and the problem of computational efficiency. While simplifying the calculation, it makes the simulation effect of the trailer more realistic.

[0176] The following is a detailed explanation of the process of updating the trailer speed based on the tractor unit:

[0177] Considering that the specific trajectory of a trailer is generally related to the rear wheelbase of both the tractor and trailer, as well as the mass of the tractor, and that a truck dynamics model is required for calculation, frequent calls to the dynamics model can lead to low computational efficiency, which is detrimental to the efficient operation of large-scale traffic simulations. Therefore, this application introduces a relatively easy-to-implement calculation method that can calculate the lane-changing trajectory of trailers with high efficiency while minimizing the impact on the factors considered in the traffic simulation.

[0178] The following example mainly uses a target lane-changing vehicle consisting of a tractor-trailer and a trailer:

[0179] In traffic simulation, vehicles follow a certain car-following (or following-vehicle) model algorithm in their longitudinal motion. This algorithm only reacts to the longitudinal speed and position of the vehicle in front of it (in the distance-time (st) coordinate system), and does not react to vehicles traveling laterally in adjacent lanes, unless a lane-changing judgment is made. When a vehicle is traveling normally longitudinally (along the lane centerline, without changing lanes) on a road with non-zero curvature (such as a curve), since the tractor and trailer cabs always remain within the lane (i.e., assuming the trailer will not leave the lane due to the tractor turning, meaning all parts of the vehicle body remain within the lane), the lateral deviation of the trailer can be ignored if the vehicle does not change lanes. That is, only the longitudinal speed of the trailer is always the same as the tractor, while its lateral speed is always one T behind the tractor. d Time. Under this assumption, the trailer's longitudinal speed is consistent with that of the tractor unit, which is controlled solely by the car-following algorithm. The vehicles behind the trailer will only react to the longitudinal speed and position of the trailer and tractor unit. Therefore, ignoring the effect of deviation will not affect the vehicle's longitudinal car-following.

[0180] During the lane-changing process of the tractor and trailer, this embodiment assumes that the vehicles both change lanes from the center line of their current lane to the center line of the target lane, and the time elapsed is the lane-changing duration T. Therefore, the longitudinal speeds of the two vehicles remain consistent, while the lateral distances covered are the same. If the tractor moves from lane T... a If the lane change begins at a certain time, then the time it spends in the lane change process (i.e., the period during which its lateral speed is not zero) is [T]. a T a +T], because the trailer lags behind the tractor by T d Therefore, for the trailer, the time it spends in the lane-changing process is [T]. a +T d T a +T+T d This is defined as the lane-changing time interval for trailers.

[0181] In one alternative implementation, the trailer and the tractor are connected by a hook or a towing pin. Therefore, in this application, it is assumed that the longitudinal speed of the trailer and the tractor are always consistent, that is, the second longitudinal speed of each trailer is adjusted to be consistent with the first longitudinal speed of the tractor. When multiple trailers are sequentially attached longitudinally behind a tractor, the longitudinal speed of these multiple trailers is consistent with that of the tractor.

[0182] As for the lateral velocity, assuming V x0 (t) and V x1(t) are the lateral speeds of the tractor and the trailer at time t, which can be specifically divided into the following two cases:

[0183] When not considering the deviation phenomenon, that is, when the deviation adjustment coefficient is 0, for any time t, the lateral speed V x1 (t) = V x0 (t - T d ), that is, the lateral speed of the trailer needs to follow the lateral speed of the tractor T d before.

[0184] When considering Figure 5 the deviation phenomenon in, an optional implementation is that for each trailer, the following operations are performed respectively:

[0185] For a trailer, when calculating the speed of the trailer at a certain moment, it is first necessary to determine whether the trailer is in its corresponding lane-changing time interval. Based on the judgment result, it is discussed in different cases, which are specifically divided into the following two cases:

[0186] Case 1: If the trailer is not in its corresponding lane-changing time interval at the current moment, it is determined that the second lateral speed of the trailer at the current moment is zero.

[0187] For example, if the lane-changing time interval corresponding to trailer A is [t1, t2], and the current moment is t3, t3 < t1, that is, it is not in this lane-changing time interval. Therefore, the lateral speed (also called the second lateral speed) of trailer A at this moment can be set to 0.

[0188] Case 2: If the trailer is in its corresponding lane-changing time interval at the current moment, the first lateral speed of the tractor is adjusted through the deviation adjustment coefficient to obtain the second lateral speed of the trailer at the current moment.

[0189] Still taking trailer A as an example above, if the current moment is t4, t1 < t4 < t2, and it is in this lane-changing time interval. Therefore, it is necessary to adjust the first lateral speed of the tractor based on the deviation adjustment coefficient to obtain the lateral speed (also called the second lateral speed) of trailer A at this moment.

[0190] In the above implementation, by judging the lane-changing time interval, it can be simply distinguished whether the trailer generates a lateral speed to determine different calculation methods, which is simple and convenient and can effectively improve the calculation efficiency and the simulation operation efficiency.

[0191] Optionally, considering that the generation of the trailer lateral speed is later than that of the tractor, therefore, when adjusting the first lateral speed of the tractor through the deviation adjustment coefficient to obtain the second lateral speed of the trailer at the current moment, the specific process is as follows:

[0192] Refer to Figure 10The diagram shown is a schematic representation of a trailer lateral speed adjustment in an embodiment of this application. Assuming the lane-changing duration is T, for the tractor, in the calculation of the lateral lane-changing position defined by the fifth-order polynomial, the lane-changing start time T is used as the starting point. a Taking a lane change time of t = T / 2 as an example, the lateral speed reaches its maximum value when the lane change time is t = T / 2. For instance, assuming the lane change duration is T = 4 seconds, and the lane change distance equals the lane width (4.5 meters), T... d = 1 second, then the lateral speed of the tractor when changing lanes is as follows: Figure 10 As shown by the solid line, the lateral speed of the tractor unit reaches its maximum value at the 2nd second when it changes lanes.

[0193] In this example, compared to the tractor's lateral velocity, the trailer's lateral velocity differs only in time (T). d In addition to the lag, the amplitude was also adjusted in segments (here, t=0 is calculated from the point where the trailer's lateral speed is not zero, that is, for the trailer, Figure 10 The dotted line in the middle is shifted to the left by T. d (Obtained in time, i.e., 1 second).

[0194] Based on the above analysis, one possible implementation method is as follows:

[0195] Based on the critical point, the lane-changing time corresponding to the trailer is divided into a first lane-changing time sub-interval and a second lane-changing time sub-interval; where the critical point is the time when the trailer reaches its maximum lateral speed, and relative to the tractor unit, this critical point also has a time interval T. d Time lag.

[0196] Based on this, when adjusting the first lateral speed of the tractor unit using the deviation adjustment coefficient to obtain the second lateral speed of the trailer, the process can be divided into the following two steps:

[0197] Process 1: If a trailer is in the first lane change time sub-interval, the first lateral speed is decelerated and adjusted based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0198] That is, based on this deviation adjustment coefficient, the tractor unit will be adjusted at tT d The first lateral velocity at time t is adjusted downwards to obtain the second lateral velocity of the trailer at time t.

[0199] Optionally, the difference between the preset parameters and the deviation adjustment coefficient can be used as the deceleration coefficient; furthermore, based on the tractor vehicle's tT d The first lateral velocity at time t, along with the deceleration coefficient, determines the second lateral velocity of the trailer at time t, where t is the current time and T is the deceleration coefficient. d This represents the lateral lag time corresponding to one trailer.

[0200] Taking the deviation adjustment coefficient as α as an example, assuming α is greater than 0 and less than 1, and the preset parameter is 1, the calculation formula for a second lateral velocity is as follows:

[0201] In t∈[T] a +T d T a +T / 2+T d When V x1 (t)=(1-α)·V x0 (tT d ).

[0202] Among them, T a T represents the start time of the lane change for the tractor unit, and T represents the corresponding lane change duration.

[0203] Step 2: If a trailer is in the second lane-changing time sub-interval, the first lateral speed is adjusted based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0204] That is, based on this deviation adjustment coefficient, the tractor unit will be adjusted at tT d The first lateral velocity at time t is adjusted upwards to obtain the second lateral velocity of the trailer at time t.

[0205] Optionally, the sum of the preset parameters and the deviation adjustment coefficient can be used as the speed increase coefficient; furthermore, based on the tractor vehicle's speed in tT d The first lateral velocity at time t, along with the growth rate coefficient, determines the second lateral velocity of a trailer at time t.

[0206] Taking the deviation adjustment coefficient as α as an example, assuming α is greater than 0 and less than 1, and the preset parameter is 1, the formula for calculating the second lateral velocity is as follows:

[0207] In t∈(T) a +T / 2+T d T a +T+T d When V x1 (t)=(1+α)·V x0 (tT d ).

[0208] That is, before reaching the maximum lateral speed, the magnitude of the first lateral speed of the tractor is reduced accordingly, and after reaching the maximum lateral speed, the speed is increased accordingly.

[0209] It should be noted that, in order to clearly demonstrate the effect of speed adjustment, Figure 10 To shift the time axis (shift the trailer's speed curve to the left by T) d=1 second) After that, the diagram shows the lateral speed adjustment of the trailer (assuming the lane change duration T = 4 seconds, the lane width = 4.5 meters, T d = 1 second), the dashed line is the trailer's lateral virtual speed after shifting the original speed along the time axis, and the solid line is the speed of the tractor that it needs to keep up with before adjusting for deviation. It can be seen that before 2 seconds, the dashed line is below the solid line, which means that the trailer's lateral speed is lower than the tractor's speed at the corresponding time, and conversely, it becomes higher after 2 seconds.

[0210] In this example, the lateral positional relationship between the trailer and the tractor is as follows: Figure 11 As shown, this is a schematic diagram of the lateral positional relationship of a trailer in an embodiment of this application. Figure 11 In the diagram, the vertical axis represents the lateral distance from the current lane centerline (in the ST coordinate system). The solid line represents the lateral position of the tractor unit over time, and the thin dashed line represents the lateral position of the trailer. Before any lane deviation adjustment is made, the two should differ by only one time lag T. d = 1 second. To clearly show the relationship between the two amplitudes, the thin dashed line is shifted T to the left. d =After 1 second, the thick dashed line is compared with the thick solid line. After the deviation adjustment, the thick dashed line is always below the thick solid line. That is, at the same "time", the lateral displacement of the trailer is always smaller than that of the tractor. In other words, the lateral position of the trailer is always closer to the original position before the lane change than that of the tractor. This shows that the trajectory of the trailer is always within the trajectory of the tractor throughout the lane change process, which is consistent with the deviation at low speed.

[0211] In summary, this application first simulates the tractor and trailer as different rigid bodies, and describes the longitudinal and lateral motion of the trailer separately. It introduces a deviation adjustment coefficient to describe the lateral deviation of the trailer when changing lanes. It uses a relatively simple method to describe their motion, which well balances the realism of the trajectory during lane changes and the problem of computational efficiency. While ensuring computational efficiency, it also ensures the realism of the simulated vehicle motion, thereby improving the running efficiency and realism of large-scale simulations at the same time.

[0212] See Figure 12 The diagram shown is a flowchart illustrating the update speed of a trailer in an embodiment of this application. Taking traffic simulation with multiple trailers, each including only one trailer, as an example, the specific implementation flow of this method is as follows:

[0213] S1201: Preparing to update the speed of the trailer;

[0214] S1202: Determine whether all trailers have been traversed at the current simulation moment. If yes, proceed to step S1211; otherwise, proceed to step S1203.

[0215] S1203: Select a trailer that has not yet been traversed by the following process and update the longitudinal and lateral speeds of the tractor.

[0216] S1204: Update the longitudinal speed of the trailer to match that of its tractor;

[0217] S1205: Determine whether the trailer is within the lane-changing time interval. If yes, proceed to step S1206; otherwise, proceed to step S1207.

[0218] S1206: Determine whether it is within the first T / 2 of the lane change time interval (i.e., whether it is within the first lane change time sub-interval). If yes, proceed to step S1208; otherwise, proceed to step S1209.

[0219] S1207: Lateral velocity is 0;

[0220] S1208: Deceleration adjustment is achieved through a deviation adjustment coefficient;

[0221] S1209: Adjust the growth rate by using the deviation adjustment coefficient;

[0222] S1210: Update trailer orientation angle based on lateral and longitudinal speeds;

[0223] S1211: Continue with other simulation modules;

[0224] S1212: Determine if the simulation time has expired. If yes, proceed to step S1213; otherwise, proceed to step S1214.

[0225] S1213: Simulation ends;

[0226] S1214: The simulation clock continues to advance.

[0227] Traffic simulation can be implemented based on a traffic simulation model. Before the traffic simulation model is officially run, the data and travelers' plans need to be initialized, and then an iterative process begins. Each iteration corresponds to one simulation step.

[0228] The above process describes that, within a simulation step, when it's the trailer's turn to be updated, the longitudinal speed of the tractor is first updated using a car-following model, based on the speed and position of the vehicle ahead. The trailer's longitudinal speed also remains consistent with the tractor's. When the tractor considers rule-based lane changing, it takes into account the length of both the trailer and its own tractor (i.e., the total vehicle length) and assesses lane-changing conditions such as safety distance. If all conditions are met, it begins the lane-changing process, calculating the coefficients of a fifth-order polynomial based on the lane-changing duration and the distance traversed, and updating the lateral speed. The trailer adjusts its speed accordingly based on whether it is within the lane-changing time interval and whether it is in the first or second half of the interval. After both longitudinal and lateral speeds are updated, the trailer's attitude is adjusted based on the vector synthesis results.

[0229] After traversing all trailers, other modules of the simulation can be run. There are no restrictions on these other modules; for example, updating vehicle positions. Once all modules have been updated within this step, the simulation clock continues to advance.

[0230] When the simulation runs out, the entire module can be terminated. There are no restrictions here; we will only focus on the trailer speed update process.

[0231] Based on the same inventive concept, embodiments of this application also provide a traffic simulation device. For example... Figure 13 As shown, this is a structural schematic diagram of the traffic simulation device 1300, which may include:

[0232] The determining unit 1301 is used to determine the target lane-changing vehicle to be simulated, and the first driving data of the tractor in the target lane-changing vehicle. The target lane-changing vehicle also includes at least one trailer towed by the tractor.

[0233] The adjustment unit 1302 is used to adjust the first driving data based on the lane-changing time interval of at least one trailer by means of a deviation adjustment coefficient to obtain the second driving data of at least one trailer. The deviation adjustment coefficient is an adjustment parameter used to address the deviation phenomenon of the trailer relative to the tractor during the lane-changing process. The lane-changing time interval is the time interval from the start of the lane-changing to the end of the lane-changing for the corresponding trailer.

[0234] Update unit 1303 is used to update the lane-changing trajectory of each trailer based on each second driving data.

[0235] Optionally, the first driving data includes a first lateral velocity and a first longitudinal velocity; the second driving data includes a second lateral velocity and a second longitudinal velocity.

[0236] Adjustment unit 1302 is specifically used for:

[0237] For each trailer, perform the following operations:

[0238] Adjust the second longitudinal speed of a trailer to the first longitudinal speed of the tractor.

[0239] If a trailer is in its corresponding lane-changing time interval, the first lateral speed of the tractor is adjusted by the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0240] Optionally, the adjustment unit 1302 is also used for:

[0241] If a trailer is not in its corresponding lane-changing time interval, then the second lateral speed of the trailer is determined to be zero.

[0242] Optionally, the lane-changing time interval includes: a first lane-changing time sub-interval and a second lane-changing time sub-interval obtained based on a critical point; the critical point is the time it takes for a trailer to reach its maximum lateral speed.

[0243] Adjustment unit 1302 is specifically used for:

[0244] If a trailer is in the first lane change time sub-interval, the first lateral speed is decelerated and adjusted based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0245] If a trailer is in the second lane-changing time sub-interval, the first lateral speed is adjusted based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

[0246] Optionally, the adjustment unit 1302 is specifically used for:

[0247] The difference between the preset parameter and the deviation adjustment coefficient is used as the deceleration coefficient; the preset parameter is greater than the deviation adjustment coefficient.

[0248] Based on the tractor in tT d The first lateral velocity at time t, along with the deceleration coefficient, determines the second lateral velocity of a trailer at time t, where t is the current time and T is the deceleration coefficient. d The lateral lag time is the time that a trailer lags behind the tractor in terms of lateral speed.

[0249] Optionally, the adjustment unit 1302 is specifically used for:

[0250] The sum of the preset parameters and the deviation adjustment coefficient is used as the growth rate coefficient; the preset parameters are greater than the deviation adjustment coefficient.

[0251] Based on the tractor in tT d The first lateral velocity at time t, along with the acceleration coefficient, determines the second lateral velocity of a trailer at time t, where t is the current time and T is the acceleration coefficient.d The lateral lag time is the time that a trailer lags behind the tractor in terms of lateral speed.

[0252] Optionally, the adjustment unit 1302 is also used to determine the lane-changing time interval corresponding to each trailer in the following ways:

[0253] Obtain the lane-changing duration corresponding to the tractor, as well as the lane-changing start time;

[0254] The corresponding lane change end time is determined based on the lane change duration and the lane change start time;

[0255] Based on the lateral lag time corresponding to a trailer and the start time of lane change, the left boundary of the lane change time interval is determined, and based on the lateral lag time corresponding to a trailer and the end time of lane change, the right boundary of the lane change time interval is determined; the lateral lag time is the lag time of a trailer relative to the tractor in generating lateral speed.

[0256] Optionally, the lateral lag time is determined based on the inherent characteristics of the target lane-changing vehicle; for a trailer, the corresponding lateral lag time of a trailer is positively correlated with the distance between the trailer and the tractor.

[0257] Optionally, the first driving data includes a first lateral velocity and a first longitudinal velocity;

[0258] The determining unit 1301 is specifically used to determine the first driving data of the tractor in the following ways:

[0259] Based on the third driving data of the vehicle in front of the target lane-changing vehicle in the same lane, and the distance between the vehicle in front and the target lane-changing vehicle, the first longitudinal speed of the tractor is determined; the same lane is the current lane before lane change or the target lane after lane change.

[0260] Based on the lane change duration and lane change distance, the first lateral speed of the tractor is determined. The lane change distance is the lateral distance that the target lane-changing vehicle needs to cross during the process of changing from the current lane to the target lane.

[0261] Optionally, the deviation adjustment factor can be determined using any of the following methods:

[0262] Obtain the pre-set deviation adjustment coefficient;

[0263] Based on the inherent characteristics of the target lane-changing vehicle, the deviation adjustment coefficient is determined.

[0264] Optionally, the second driving data includes a second lateral speed and a second longitudinal speed;

[0265] Update unit 1303 is specifically used for:

[0266] Perform the following operations for each trailer:

[0267] For a trailer, the second lateral velocity and the second longitudinal velocity of the trailer are vectored together to determine the heading angle of the trailer;

[0268] Based on the heading angle, the driving posture of a trailer is adjusted, and the lane-changing trajectory of a trailer is updated based on the adjustment result.

[0269] This application defines the tractor and trailer as two independent objects and describes the longitudinal and lateral motion of the trailer separately. It introduces a deviation adjustment coefficient to describe the deviation of the trailer during lane changes. The description of trailer deviation only needs to be obtained by adjusting the driving data of the tractor based on the deviation adjustment coefficient. There is no need to build a detailed dynamic model. It uses a relatively simple method to describe the motion of the tractor and trailer, which well balances the realism of the trajectory during lane changes and the problem of computational efficiency. While simplifying the calculation, it makes the simulation effect of the trailer more realistic.

[0270] For ease of description, the above sections are divided into modules (or units) according to their functions and described separately. Of course, in implementing this application, the functions of each module (or unit) can be implemented in one or more software or hardware components.

[0271] Having introduced the traffic simulation method and apparatus according to exemplary embodiments of this application, we will now introduce an electronic device according to another exemplary embodiment of this application.

[0272] Those skilled in the art will understand that various aspects of this application can be implemented as a system, method, or program product. Therefore, various aspects of this application can be specifically implemented in the following forms: a completely hardware implementation, a completely software implementation (including firmware, microcode, etc.), or a combination of hardware and software implementations, collectively referred to herein as a "circuit," "module," or "system."

[0273] Based on the same inventive concept as the above-described method embodiments, this application also provides an electronic device. In this embodiment, the structure of the electronic device can be as follows: Figure 14 As shown, it includes a memory 1401, a communication module 1403, and one or more processors 1402.

[0274] The memory 1401 is used to store computer programs executed by the processor 1402. The memory 1401 may mainly include a program storage area and a data storage area. The program storage area may store the operating system and programs required to run instant messaging functions, etc.; the data storage area may store various instant messaging information and operation instruction sets, etc.

[0275] Memory 1401 may be volatile memory, such as random-access memory (RAM); memory 1401 may also be non-volatile memory, such as read-only memory, flash memory, hard disk drive (HDD), or solid-state drive (SSD); or memory 1401 may be any other medium capable of carrying or storing a desired computer program having the form of instructions or data structures and accessible by a computer, but is not limited thereto. Memory 1401 may be a combination of the above-described memories.

[0276] The processor 1402 may include one or more central processing units (CPUs) or digital processing units, etc. The processor 1402 is used to implement the traffic simulation method described above when it calls the computer program stored in the memory 1401.

[0277] The communication module 1403 is used to communicate with terminal devices and other servers.

[0278] This application embodiment does not limit the specific connection medium between the memory 1401, communication module 1403, and processor 1402. This application embodiment... Figure 14 The memory 1401 and the processor 1402 are connected via a bus 1404, and the bus 1404 is in Figure 14 The diagram uses thick lines to describe the connections between other components; these are for illustrative purposes only and should not be considered limiting. The 1404 bus can be divided into address bus, data bus, control bus, etc. For ease of description, Figure 14 It is described using only a thick line, but does not indicate that there is only one bus or one type of bus.

[0279] The memory 1401 stores a computer storage medium, which in turn stores computer-executable instructions for implementing the traffic simulation method of this application embodiment. The processor 1402 is used to execute the aforementioned traffic simulation method, such as... Figure 2 As shown.

[0280] The following reference Figure 15 To describe a computing device 150 according to this embodiment of the present application. Figure 15 The computing device 150 is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0281] like Figure 15 The computing device 150 is manifested in the form of a general-purpose computing device. The components of the computing device 150 may include, but are not limited to: at least one processing unit 151, at least one storage unit 152, and a bus 153 connecting different system components (including storage unit 152 and processing unit 151).

[0282] Bus 153 represents one or more of several bus structures, including a memory bus or memory controller, peripheral bus, processor, or local bus using any of the various bus structures.

[0283] Storage unit 152 may include a readable medium in the form of volatile memory, such as random access memory (RAM) 1521 and / or cache storage unit 1522, and may further include read-only memory (ROM) 1523.

[0284] Storage unit 152 may also include a program / utility 1525 having a set (at least one) program module 1524, such program module 1524 including but not limited to: operating system, one or more application programs, other program modules and program data, each of these examples or some combination of these may include an implementation of a network environment.

[0285] The computing device 150 can also communicate with one or more external devices 154 (e.g., keyboard, pointing device, etc.), one or more devices that enable a user to interact with the computing device 150, and / or any device that enables the computing device 150 to communicate with one or more other computing devices (e.g., router, modem, etc.). This communication can be performed via input / output (I / O) interface 155. Furthermore, the computing device 150 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 156. As shown, network adapter 156 communicates with other modules for the computing device 150 via bus 153. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with the computing device 150, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0286] In some possible implementations, various aspects of the traffic simulation method provided in this application can also be implemented in the form of a program product, which includes a computer program. When the program product is run on an electronic device, the computer program causes the electronic device to perform the steps in the traffic simulation method according to the various exemplary embodiments of this application described above. For example, the electronic device can perform actions such as... Figure 2The steps are shown in the figure.

[0287] The program product may employ any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0288] The program product of the embodiments of this application may employ a portable compact disc read-only memory (CD-ROM) and include a computer program, and may run on an electronic device. However, the program product of this application is not limited thereto. In this document, the readable storage medium may be any tangible medium that contains or stores a program that may be used by or in conjunction with a command execution system, apparatus, or device.

[0289] A readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying a readable computer program. This propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium, capable of sending, propagating, or transmitting a program for use by or in conjunction with a command execution system, apparatus, or device.

[0290] Computer programs contained on readable media may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination thereof.

[0291] Computer programs for performing the operations of this application can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, and conventional procedural programming languages ​​such as C or similar languages. The computer program can execute entirely on the user's electronic device, partially on the user's electronic device, as a standalone software package, partially on the user's electronic device and partially on a remote electronic device, or entirely on a remote electronic device or server. In cases involving remote electronic devices, the remote electronic device can be connected to the user's electronic device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external electronic device (e.g., via the Internet using an Internet service provider).

[0292] It should be noted that although several units or sub-units of the device have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of this application, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of one unit described above can be further divided and embodied by multiple units.

[0293] Furthermore, although the operations of the method of this application are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0294] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing a computer-usable computer program.

[0295] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, produce a machine for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0296] These computer program commands may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the commands stored in the computer-readable storage medium produce an article of manufacture including command means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0297] These computer program commands can also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing the commands executed on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0298] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0299] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A traffic simulation method, characterized in that, The method includes: The target lane-changing vehicle to be simulated is determined, and the first driving data of the tractor unit in the target lane-changing vehicle is determined; the target lane-changing vehicle also includes at least one trailer towed by the tractor unit, and the first driving data includes a first lateral speed and a first longitudinal speed. For each trailer, the following steps are performed: the second longitudinal speed of a trailer is adjusted to the first longitudinal speed of the tractor; if the trailer is within its corresponding lane-changing time interval, the first lateral speed of the tractor is adjusted using a lane-shifting adjustment coefficient to obtain the second lateral speed of the trailer, and the second longitudinal speed and the second lateral speed are determined as the second driving data of the trailer; the lane-shifting adjustment coefficient is an adjustment parameter used during lane-changing to address the lane-shifting phenomenon of the trailer relative to the tractor, and the lane-changing time interval is the time interval from the start to the end of the lane-changing for the corresponding trailer; Each trailer's lane-changing trajectory is updated based on the second driving data.

2. The method as described in claim 1, characterized in that, The method further includes: If a trailer is not in its corresponding lane-changing time interval, then the second lateral speed of the trailer is determined to be zero.

3. The method as described in claim 1, characterized in that, The lane-changing time interval includes: a first lane-changing time sub-interval and a second lane-changing time sub-interval, which are divided based on a critical point; the critical point is the time when the trailer reaches its maximum lateral speed. The step of adjusting the first lateral speed of the tractor unit by using a deviation adjustment coefficient to obtain the second lateral speed of the trailer includes: If a trailer is in the first lane-changing time sub-interval, the first lateral speed is decelerated and adjusted based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer. If a trailer is in the second lane-changing time sub-interval, the first lateral speed is adjusted to increase the speed based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer.

4. The method as described in claim 3, characterized in that, The step of adjusting the first lateral speed based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer includes: The difference between the preset parameter and the deviation adjustment coefficient is used as the deceleration coefficient; the preset parameter is greater than the deviation adjustment coefficient. Based on the aforementioned tractor at tT d The first lateral velocity at time t, together with the deceleration coefficient, determines the second lateral velocity of the trailer at time t, where t is the current time and T is the deceleration coefficient. d The lateral lag time is the time that the trailer lags behind the tractor in generating lateral speed.

5. The method as described in claim 3, characterized in that, The step of adjusting the first lateral speed based on the deviation adjustment coefficient to obtain the second lateral speed of the trailer includes: The sum of the preset parameter and the deviation adjustment coefficient is used as the growth coefficient; the preset parameter is greater than the deviation adjustment coefficient. Based on the aforementioned tractor at tT d The first lateral velocity at time t, together with the growth coefficient, determines the second lateral velocity of the trailer at time t, where t is the current time and T is the speed of the trailer. d The lateral lag time is the time that the trailer lags behind the tractor in generating lateral speed.

6. The method as described in claim 1, characterized in that, The lane-changing time interval for each trailer is determined using the following method: Obtain the lane-changing duration and lane-changing start time corresponding to the tractor; Based on the lane change duration and the lane change start time, the corresponding lane change end time is determined; Based on the lateral lag time corresponding to a trailer and the start time of the lane change, the left boundary of the lane change time interval is determined, and based on the lateral lag time corresponding to a trailer and the end time of the lane change, the right boundary of the lane change time interval is determined; the lateral lag time is the lag time of the trailer relative to the tractor in generating lateral speed.

7. The method according to any one of claims 4 to 6, characterized in that, The lateral lag time is determined based on the inherent characteristics of the target lane-changing vehicle; for a trailer, the corresponding lateral lag time of the trailer is positively correlated with the distance between the trailer and the tractor.

8. The method according to any one of claims 1 to 6, characterized in that, The first driving data of the tractor is determined by the following method: Based on the third driving data of the vehicle preceding the target lane-changing vehicle in the same lane, and the distance between the preceding vehicle and the target lane-changing vehicle, the first longitudinal speed of the tractor is determined; the same lane is either the current lane before lane changing or the target lane after lane changing. Based on the lane change duration and lane change distance, the first lateral speed of the tractor is determined, whereby the lane change distance is the lateral distance that the target lane-changing vehicle needs to traverse during the process of changing from the current lane to the target lane.

9. The method according to any one of claims 1 to 6, characterized in that, The deviation adjustment coefficient is determined by any of the following methods: Obtain the pre-set deviation adjustment coefficient; The deviation adjustment coefficient is determined based on the inherent characteristics of the target lane-changing vehicle.

10. The method according to any one of claims 1 to 6, characterized in that, The process of updating the lane-changing trajectory of each trailer based on the respective second driving data includes: Perform the following operations for each trailer: For a trailer, the second lateral velocity and the second longitudinal velocity of the trailer are vectored together to determine the heading angle of the trailer; Based on the heading angle, the driving posture of the trailer is adjusted, and the lane-changing trajectory of the trailer is updated based on the adjustment result.

11. A traffic simulation device, characterized in that, include: The determining unit is used to determine the target lane-changing vehicle to be simulated, and the first driving data of the tractor in the target lane-changing vehicle; The target lane-changing vehicle also includes at least one trailer towed by the tractor, and the first driving data includes a first lateral speed and a first longitudinal speed; The adjustment unit is used to perform the following for each trailer: adjusting the second longitudinal speed of a trailer to the first longitudinal speed of the tractor; if the trailer is in its corresponding lane-changing time interval, adjusting the first lateral speed of the tractor through a deviation adjustment coefficient to obtain the second lateral speed of the trailer, and determining the second longitudinal speed and the second lateral speed as the second driving data of the trailer; the deviation adjustment coefficient is an adjustment parameter used during lane changing to address the deviation phenomenon of the trailer relative to the tractor, and the lane-changing time interval is the time interval corresponding to the start and end of the lane change for the corresponding trailer; The update unit is used to update the lane-changing trajectory of each trailer based on each second driving data.

12. An electronic device, characterized in that, It includes a processor and a memory, wherein the memory stores a computer program that, when executed by the processor, causes the processor to perform the steps of any of the methods described in claims 1 to 10.

13. A computer-readable storage medium, characterized in that, It includes a computer program that, when run on an electronic device, causes the electronic device to perform the steps of any of the methods described in claims 1 to 10.

14. A computer program product, characterized in that, The method includes a computer program stored in a computer-readable storage medium; when a processor of an electronic device reads the computer program from the computer-readable storage medium, the processor executes the computer program, causing the electronic device to perform the steps of any one of claims 1 to 10.

Images