Vehicle following control method and system, vehicle and equipment

Abstract

The invention discloses a vehicle following control method and system, a vehicle and equipment. The vehicle following control method of the vehicle comprises the steps that driving information of a front vehicle and a future track of the front vehicle are obtained; according to the driving information and the future trajectory of the preceding vehicle, obtaining a planned reference line when the vehicle follows the preceding vehicle; according to the planning reference line, an s-t graph projection of the position of the front vehicle changing along with time is obtained; and according to a set vehicle following strategy and the s-t graph projection of the front vehicle, determining a vehicle following speed curve of the vehicle. By the adoption of the method and device, the response speed of speed control during car following after automatic driving is improved, the shorter car following distance is achieved, and the safety and car following efficiency of the automatic driving car are improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a vehicle following control method, system, vehicle and equipment. Background Art

[0002] Platooning autonomous driving adds V2V (Vehicle to Vehicle) communication technology to autonomous driving technology, allowing vehicles in the same platoon to share vehicle perception, positioning, control and motion status information through V2V, thereby enabling vehicles in the queue to travel at a smaller following distance, achieving the effect of reducing air resistance, improving traffic efficiency, enhancing driving safety and reducing the burden on drivers.

[0003] String Stability is a very important concept in autonomous driving platooning control, which is used to measure the dynamic stability of platoon vehicles in longitudinal following control. Specifically, platoon stability describes whether the vehicles in the platoon can avoid the gradual amplification of disturbances (such as the sudden deceleration of the leading vehicle) when they are disturbed, so as to ensure that the following vehicles do not experience greater speed or acceleration fluctuations, thereby maintaining the stability and safety of the entire platoon. In terms of longitudinal following control of platooning autonomous driving, existing technologies use the acceleration or throttle / brake pedal signals of the leading vehicle received by V2V as feedforward signals, and combine the error feedback of speed and following distance to control the acceleration and deceleration of the following vehicle to achieve a shorter following distance and platoon stability.

[0004] Existing feedforward-plus-feedback control methods only consider the current state or control command of the leading vehicle when calculating the desired acceleration of the following vehicle. The calculated desired acceleration is simply to eliminate the current speed error and following distance error with the leading vehicle. However, in real-world vehicle control, if the leading vehicle's speed fluctuates significantly, the V2V transmission delay is large, or the chassis's response to control commands is slow, it becomes difficult to maintain a stable platoon at a small following distance. In severe cases, the following vehicle may not be able to slow down in time, resulting in a rear-end collision. Summary of the Invention

[0005] Based on this, it is necessary to provide a vehicle following control method, system, vehicle and equipment to address the above technical problems, thereby improving the response speed of speed control when the autonomous driving rear vehicle follows the vehicle, achieving a shorter following distance, and improving the safety and following efficiency of the autonomous driving vehicle.

[0006] In a first aspect, a vehicle following control method is provided, comprising:

[0007] Obtain the driving information and future trajectory of the preceding vehicle;

[0008] Obtaining a planning reference line for the self-vehicle when following the preceding vehicle based on the preceding vehicle's driving information and future trajectory;

[0009] According to the planning reference line, an ST graph projection of the position of the preceding vehicle changing with time is obtained;

[0010] According to the set following strategy and the ST diagram projection of the preceding vehicle, the following speed curve of the vehicle is determined.

[0011] In some examples, obtaining the driving information of the preceding vehicle and the future trajectory of the preceding vehicle includes:

[0012] Get the planned trajectory of the preceding vehicle;

[0013] If the planned trajectory of the preceding vehicle is obtained, the planned trajectory of the preceding vehicle is used as the future trajectory of the preceding vehicle;

[0014] If the planned trajectory of the preceding vehicle is not obtained, the predicted trajectory of the preceding vehicle is obtained based on the driving information of the preceding vehicle, and the predicted trajectory is used as the future trajectory of the preceding vehicle.

[0015] The driving information of the preceding vehicle includes at least the position, heading, speed, acceleration and yaw rate of the preceding vehicle.

[0016] In some examples, obtaining a planning reference line for the ego vehicle to follow the leading vehicle based on the driving information and future trajectory of the leading vehicle includes:

[0017] Obtaining a historical path of the preceding vehicle based on the driving information of the preceding vehicle;

[0018] A planning reference line of the vehicle is fitted based on the historical path of the preceding vehicle and the future trajectory.

[0019] In some examples, obtaining, based on the planning reference line, an ST map projection of the position of the preceding vehicle over time includes:

[0020] Establishing a curvilinear coordinate system according to the planning reference line;

[0021] In the curvilinear coordinate system, the sl coordinates of the vehicle and the preceding vehicle are obtained;

[0022] According to the sl coordinates of the preceding vehicle, an st graph projection of the preceding vehicle's position changing with time is obtained.

[0023] In some examples, determining the following speed curve of the vehicle according to the set following strategy and the ST map projection of the preceding vehicle includes:

[0024] According to the fixed-time-headroom following strategy, the expected following distance of the ego vehicle at time t is determined, where the expected following distance is:

[0025] d t =vi,t THW+d safe ,

[0026] Among them, d t is the expected following distance, v i,t is the speed of the vehicle at time t, THW is the set time distance to follow the vehicle, d safe A safe parking distance;

[0027] According to the position of the preceding vehicle at each moment, the expected position of the vehicle is obtained, where the expected position of the vehicle is:

[0028] s d,t =s 1,t -d t ,

[0029] Among them, s d,t is the expected position of the vehicle at time t, s 1,t is the position of the rear end of the preceding vehicle at time t;

[0030] According to the expected position of the ego vehicle at each moment, the following speed curve of the ego vehicle is determined.

[0031] In some examples, determining the following speed curve of the ego vehicle based on the desired position of the ego vehicle at each moment includes:

[0032] Construct the ST curve of the vehicle based on the expected position of the vehicle at each moment;

[0033] The following speed curve of the own vehicle is solved based on the ST curve of the own vehicle.

[0034] In a second aspect, a vehicle following control system is provided, comprising:

[0035] The acquisition module is used to obtain the driving information of the preceding vehicle and the future trajectory of the preceding vehicle;

[0036] A reference line generation module is used to obtain a planning reference line when the vehicle follows the preceding vehicle based on the driving information and future trajectory of the preceding vehicle;

[0037] A projection module, configured to obtain an ST graph projection of the position of the preceding vehicle changing with time based on the planned reference line;

[0038] The control module is used to determine the following speed curve of the vehicle according to the set following strategy and the ST diagram projection of the preceding vehicle.

[0039] In a third aspect, a vehicle is provided, comprising: the vehicle following control system according to the second aspect.

[0040] In a fourth aspect, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of the vehicle following control method of the first aspect and any possible implementation of the first aspect are implemented.

[0041] In a fifth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the steps of the vehicle following control method of the above-mentioned first aspect and any possible implementation method of the first aspect are implemented.

[0042] In a sixth aspect, a computer program product is provided, on which a computer program is stored. When the program is executed by a processor, the steps of the vehicle following control method of the above-mentioned first aspect and any possible implementation method of the first aspect are implemented.

[0043] According to the embodiment of the present application, the driving information and the future trajectory of the preceding vehicle are first obtained. Then, based on the driving information and the future trajectory of the preceding vehicle, the planning reference line for the self-vehicle to follow the preceding vehicle is obtained. Then, based on the planning reference line, the ST graph projection of the preceding vehicle's position changing with time is obtained. Finally, based on the set following strategy and the ST graph projection of the preceding vehicle, the self-vehicle's following speed curve is determined. Therefore, the embodiment of the present application considers the motion trajectory of the preceding vehicle for a period of time in the future at the planning level for the speed planning of the following vehicle, which can achieve a shorter following distance and ensure the following safety and queue stability. In addition, the response speed of the speed control of the following vehicle in the autonomous driving is improved, a shorter following distance is achieved, and the safety and following efficiency of the autonomous driving vehicle are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0045] Figure 1 A flow chart of a vehicle following control method provided in an embodiment of the present application;

[0046] Figure 2 A schematic diagram of an autonomous driving platoon vehicle in the vehicle following control method provided in an embodiment of the present application;

[0047] Figure 3 A schematic diagram of a planned trajectory of a leading vehicle in a vehicle following control method provided in an embodiment of the present application;

[0048] Figure 4 A schematic diagram of the predicted trajectory of a leading vehicle in the vehicle following control method provided in an embodiment of the present application;

[0049] Figure 5A schematic diagram showing the fitting of a planned reference line in the vehicle following control method provided in an embodiment of the present application;

[0050] Figure 6 A schematic diagram of the s1 coordinates of the vehicle and the preceding vehicle in a curved coordinate system in the vehicle following control method provided in an embodiment of the present application;

[0051] Figure 7 This is a schematic diagram of the ST diagram projection of the leading vehicle in the vehicle following control method provided in an embodiment of the present application under the conditions of uniform speed, uniform acceleration and uniform deceleration;

[0052] Figure 8 A schematic diagram of the ST curve of the vehicle in the vehicle following control method provided in an embodiment of the present application;

[0053] Figure 9 A schematic diagram of a non-vehicle cutting in between the vehicle and the preceding vehicle in the vehicle following control method provided in an embodiment of the present application;

[0054] Figure 10 A schematic diagram of the ST curve of the vehicle after a foreign vehicle cuts in in the vehicle following control method provided in an embodiment of the present application;

[0055] Figure 11 A structural block diagram of a vehicle following control system provided in an embodiment of the present application;

[0056] Figure 12 This is a structural block diagram of the computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0057] The present application will be further described in detail below with reference to the embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are intended only to illustrate the relevant application and are not intended to limit the application. It should also be noted that, for ease of description, only the portions relevant to the application are shown in the accompanying drawings.

[0058] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0059] The following describes in detail the vehicle following control method, system, vehicle and equipment according to the embodiments of the present application in conjunction with the accompanying drawings.

[0060] Figure 1 FIG. 1 is a flow chart of a vehicle following control method according to an embodiment of the present application. Figure 1 As shown, the vehicle following control method according to an embodiment of the present application includes the following steps:

[0061] S101: Obtain driving information of the preceding vehicle and the preceding vehicle's future trajectory.

[0062] In one embodiment of the present application, obtaining the driving information of a leading vehicle and the future trajectory of the leading vehicle includes: obtaining the planned trajectory of the leading vehicle; if the planned trajectory of the leading vehicle is obtained, using the planned trajectory of the leading vehicle as the future trajectory of the leading vehicle; if the planned trajectory of the leading vehicle is not obtained, obtaining the predicted trajectory of the leading vehicle based on the driving information of the leading vehicle, and using the predicted trajectory as the future trajectory of the leading vehicle, wherein the driving information of the leading vehicle includes at least the position, heading, speed, acceleration and yaw angular velocity of the leading vehicle.

[0063] Take the autonomous driving formation composed of N vehicles as an example, Figure 2 As shown, an autonomous driving formation consists of N vehicles, and each vehicle is numbered i=0, 1,…, N. Among them, vehicle 0 is the lead vehicle. Each vehicle in the formation except the lead vehicle receives information about its adjacent preceding vehicle through V2V, including but not limited to the preceding vehicle's speed, acceleration, position, heading angle, yaw rate, planned trajectory, perceived obstacles and other information. In the embodiment of the present application, the other vehicles in the self-parking formation except the lead vehicle are vehicles i∈[1,N]. Vehicle i can be called the self-vehicle, and vehicle i-1 can be called the preceding vehicle of the self-vehicle, i∈[1,N]. It should be noted that the lead vehicle in the formation can be an autonomous driving vehicle or a manually driven vehicle, and the other vehicles except the lead vehicle are usually autonomous driving vehicles.

[0064] The ego vehicle obtains the position, heading, speed, acceleration, and yaw rate information of the preceding vehicle. If the preceding vehicle is an autonomous vehicle, the ego vehicle also obtains the planned trajectory of the preceding vehicle. The planned trajectory contains the trajectory points of the preceding vehicle for a period of time in the future. Each trajectory point includes the position coordinates, relative time, speed, acceleration, heading angle, and yaw rate information, such as Figure 3 shown.

[0065] If the ego vehicle does not obtain the planned trajectory information of the preceding vehicle, it needs to use the preceding vehicle's position, heading, and speed as the initial state, and use the preceding vehicle's acceleration, yaw rate, and the vehicle's kinematic model to predict the preceding vehicle's trajectory in the future. Each predicted trajectory point includes position coordinates, relative time, speed, acceleration, heading angle, and yaw rate information. The acceleration and yaw rate of each predicted trajectory point are equal to the acceleration and yaw rate at the current moment. Figure 4 shown.

[0066] In the following description, the planned trajectory and predicted trajectory of the preceding vehicle are collectively referred to as the future trajectory of the preceding vehicle.

[0067] S102: Obtaining a planning reference line for the vehicle following the preceding vehicle based on the driving information and future trajectory of the preceding vehicle.

[0068] In one embodiment of the present application, a planning reference line for the vehicle following the preceding vehicle is obtained based on the driving information and future trajectory of the preceding vehicle, including: obtaining the historical path of the preceding vehicle based on the driving information of the preceding vehicle; and fitting the planning reference line of the vehicle based on the historical path of the preceding vehicle and the future trajectory.

[0069] Specifically, the ego vehicle caches the position of the preceding vehicle over the past period of time as the preceding vehicle's historical path, and extracts the position information from the preceding vehicle's future trajectory as the future path. The preceding vehicle's historical path and future path are connected, and the path points are smoothly fitted using an existing curve fitting algorithm to obtain the planning reference line of the ego vehicle. Figure 5 As shown in , the generated planning reference line can be a series of smooth discrete points or a piecewise polynomial curve.

[0070] S103: Obtaining an ST graph projection of the position of the preceding vehicle changing with time based on the planned reference line.

[0071] In one embodiment of the present application, an ST diagram projection of the position of the preceding vehicle changing with time is obtained based on the planning reference line, including: establishing a curved coordinate system based on the planning reference line; obtaining the SL coordinates of the vehicle and the preceding vehicle in the curved coordinate system; and obtaining the ST diagram projection of the position of the preceding vehicle changing with time based on the SL coordinates of the preceding vehicle.

[0072] Specifically, the fitted reference line is used as the planned path of the ego vehicle, and the existing lateral control algorithm is used to control the front wheel angle of the ego vehicle so that the ego vehicle travels along the planned path. The lateral control algorithm can be a pure tracking algorithm, PID, LQR, MPC, etc. A Frenet coordinate system (i.e., a curvilinear coordinate system) is established based on the reference line. The positive direction of s is the forward direction along the reference line, and the positive direction of l is the left direction perpendicular to the reference line. In the Frenet coordinate system, the sl coordinates of the ego vehicle and the preceding vehicle can be obtained. Figure 6 As shown, the sl coordinate corresponding to the center of the rear axle of the vehicle is (s0, l0), the sl coordinate corresponding to the center position of the rear end of the front vehicle is (s1, l1), and the sl coordinate corresponding to the center position of the front end of the front vehicle is (s2, l2).

[0073] To account for the future trajectory of the preceding vehicle, the ego vehicle's speed planning is based on the ST-graph. The ST-graph's horizontal axis represents time, and the vertical axis represents position along the reference line, or the s-coordinate in the Frenet coordinate system. The ego vehicle's current state corresponds to point (0,0) on the ST-graph. Since the ego vehicle uses the reference line as its path, the ego vehicle's future trajectory is checked at each moment to see if the preceding vehicle overlaps with the ego vehicle on the reference line. If so, the preceding vehicle is projected onto the ST-graph. Figure 7The ST diagram projection of the leading vehicle in the future for a period of time under the conditions of uniform speed, uniform acceleration and uniform deceleration is given. Figure 7 In the example, s1 and s2 are the positions of the front vehicle's rear and front at the current time (t=0), respectively. The lower edge of the front vehicle's projection corresponds to the position of its rear end in the future, and the upper edge corresponds to the position of its front end in the future.

[0074] S104: Determine a following speed curve of the vehicle according to the set following strategy and the ST graph projection of the preceding vehicle.

[0075] In one embodiment of the present application, the following speed curve of the own vehicle is determined based on the set following strategy and the ST diagram projection of the leading vehicle, including: determining the expected following distance of the own vehicle at time t based on the following strategy with a fixed time interval; obtaining the expected position of the own vehicle based on the position of the leading vehicle at each moment; and determining the following speed curve of the own vehicle based on the expected position of the own vehicle at each moment.

[0076] In this example, the following speed curve of the ego vehicle is determined based on the expected position of the ego vehicle at each moment, including: constructing the ST curve of the ego vehicle based on the expected position of the ego vehicle at each moment; and solving the following speed curve of the ego vehicle based on the ST curve of the ego vehicle.

[0077] Specifically, using a fixed time-distance following strategy, the expected following distance of the ego vehicle at time t is defined as

[0078] d t =v i,t THW+d safe

[0079] Where, d t is the expected following distance, v i,t is the speed of the vehicle at time t, THW is the set time distance to follow the vehicle, d safe This is a safe parking distance.

[0080] According to the position of the preceding vehicle at each moment, the expected position of the vehicle can be calculated:

[0081] s d,t =s 1,t -d t

[0082] Where s d,t is the expected position of the vehicle at time t, s 1,t is the position of the rear end of the preceding vehicle at time t.

[0083] On the st graph, a search algorithm (e.g., dynamic programming, A* algorithm) or a sampling-based algorithm (e.g., State Lattice algorithm) can be used to find a series of points on the st graph to form a rough st solution of the ego vehicle, so that it satisfies the vehicle's kinematic constraints, physical constraints, and safety constraints, while minimizing the error between the desired position at each moment and the relevant comfort index. The rough st solution is further smoothed using an optimization algorithm to obtain a second-order continuously differentiable ego vehicle st curve, such as Figure 8 As shown (taking the uniform deceleration of the preceding vehicle as an example), by taking the derivative of the st curve, we can obtain the velocity curve of the own vehicle.

[0084] It should be noted that, when planning the vehicle speed, the embodiment of the present application can not only consider the future trajectory of the preceding vehicle, but also other traffic participants. Figure 9 As shown in , there is another social vehicle A in the left lane that wants to cut in between the vehicle and the front vehicle. According to the predicted trajectory of vehicle A output by the prediction module, vehicle A can be projected onto the st graph, as shown in Figure 10 As shown in Figure 2. Using a search and optimization algorithm on the ST graph, an ST curve can be generated that takes into account both the preceding vehicle and other vehicles. This allows for a unified algorithmic framework that considers both vehicles in the platoon and other vehicles. This algorithm can also be used for speed planning if the ego vehicle's autonomous driving mode switches from platooning to single-vehicle autonomous driving. In this case, the only obstacles projected onto the ST graph are other vehicles, not the preceding vehicle in the platoon.

[0085] According to the vehicle following control method of the embodiment of the present application, the driving information of the leading vehicle and the future trajectory of the leading vehicle are first obtained. Then, based on the driving information and future trajectory of the leading vehicle, a planning reference line is obtained for the self-vehicle to follow the leading vehicle. Then, based on the planning reference line, an ST diagram projection of the leading vehicle's position changing with time is obtained. Finally, based on the set following strategy and the ST diagram projection of the leading vehicle, the self-vehicle following speed curve is determined. Therefore, the embodiment of the present application considers the motion trajectory of the leading vehicle for a period of time in the future at the planning level for the speed planning of the following vehicle, which can achieve a shorter following distance and ensure the following safety and queue stability. In addition, the response speed of the speed control of the following vehicle in the autonomous driving is improved, a shorter following distance is achieved, and the safety and following efficiency of the autonomous driving vehicle are improved.

[0086] Figure 11 FIG. 1 is a structural block diagram of a vehicle following control system according to an embodiment of the present application. Figure 11 As shown, a vehicle following control system according to an embodiment of the present application includes: an acquisition module 1110, a reference line generation module 1120, a projection module 1130 and a control module 1140, wherein:

[0087] An acquisition module 1110 is used to obtain the driving information of the preceding vehicle and the future trajectory of the preceding vehicle;

[0088] A reference line generation module 1120 is configured to obtain a planned reference line for the ego vehicle when following the preceding vehicle based on the preceding vehicle's driving information and future trajectory;

[0089] The projection module 1130 is used to obtain an ST map projection of the position of the preceding vehicle changing with time according to the planned reference line;

[0090] The control module 1140 is configured to determine a following speed curve of the vehicle according to a set following strategy and the ST diagram projection of the preceding vehicle.

[0091] According to the vehicle following control system of the embodiment of the present application, the driving information of the leading vehicle and the future trajectory of the leading vehicle are first obtained, and then the planning reference line when the self-vehicle follows the leading vehicle is obtained based on the driving information and future trajectory of the leading vehicle. Then, based on the planning reference line, the ST diagram projection of the position of the leading vehicle changing with time is obtained. Finally, according to the set following strategy and the ST diagram projection of the leading vehicle, the following speed curve of the self-vehicle is determined. Therefore, the embodiment of the present application considers the motion trajectory of the leading vehicle for a period of time in the future at the planning level for the speed planning of the following vehicle, which can achieve a shorter following distance and ensure the following safety and queue stability. In addition, it improves the response speed of the speed control of the following vehicle of the autonomous driving, achieves a shorter following distance, and improves the safety and following efficiency of the autonomous driving vehicle.

[0092] The specific definitions of the vehicle's following control system can be found in the definitions of the vehicle's following control method described above and will not be repeated here. Each module of the vehicle's following control system can be implemented in whole or in part through software, hardware, or a combination thereof. Each of these modules can be embedded in or independent of a processor in a computer device in hardware form, or stored in a computer device's memory in software form, so that the processor can call and execute the corresponding operations of each of these modules.

[0093] Furthermore, a vehicle is provided, comprising: a vehicle following control system according to any one of the above embodiments. When following a vehicle, the vehicle first obtains the driving information of the preceding vehicle and the future trajectory of the preceding vehicle, and then obtains a planning reference line for the vehicle following the preceding vehicle based on the driving information and future trajectory of the preceding vehicle, and then obtains an ST graph projection of the preceding vehicle's position changing with time based on the planning reference line, and finally, determines the following speed curve of the vehicle based on the set following strategy and the ST graph projection of the preceding vehicle. Therefore, the embodiment of the present application considers the motion trajectory of the preceding vehicle for a period of time in the future at the planning level for the speed planning of the following vehicle, which can achieve a shorter following distance and ensure the following safety and queue stability, thereby improving the response speed of the speed control of the following vehicle in the autonomous driving, achieving a shorter following distance, and improving the safety and following efficiency of the autonomous driving vehicle.

[0094] In addition, other structures and functions of the vehicle according to the embodiment of the present application are known to ordinary technicians in this field and will not be described in detail here.

[0095] In one embodiment, a computer device is provided. Figure 12 This is a block diagram of the computer device provided in the embodiment of the present application, refer to Figure 12 The computer device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the embodiment of the vehicle following control method is implemented. For example, the following steps are executed: obtaining the driving information of the preceding vehicle and the future trajectory of the preceding vehicle;

[0096] Obtaining a planning reference line for the self-vehicle when following the preceding vehicle based on the preceding vehicle's driving information and future trajectory;

[0097] According to the planning reference line, an ST graph projection of the position of the preceding vehicle changing with time is obtained;

[0098] According to the set following strategy and the ST diagram projection of the preceding vehicle, the following speed curve of the vehicle is determined.

[0099] The present application also provides a computer-readable storage medium storing a computer program. When the processor executes the computer program, the following vehicle control method embodiment is implemented. For example, the following method is executed: obtaining the driving information and the future trajectory of the preceding vehicle;

[0100] Obtaining a planning reference line for the self-vehicle when following the preceding vehicle based on the preceding vehicle's driving information and future trajectory;

[0101] According to the planning reference line, an ST graph projection of the position of the preceding vehicle changing with time is obtained;

[0102] According to the set following strategy and the ST diagram projection of the preceding vehicle, the following speed curve of the vehicle is determined.

[0103] The present application embodiment provides a computer program product, which includes instructions. When the instructions are executed, the method described in the embodiment of the present application is executed. For example, you can execute Figure 1 The various steps of the vehicle following control method shown, for example, are performed: obtaining driving information of a preceding vehicle and a future trajectory of the preceding vehicle;

[0104] Obtaining a planning reference line for the self-vehicle when following the preceding vehicle based on the preceding vehicle's driving information and future trajectory;

[0105] According to the planning reference line, an ST graph projection of the position of the preceding vehicle changing with time is obtained;

[0106] According to the set following strategy and the ST diagram projection of the preceding vehicle, the following speed curve of the vehicle is determined.

[0107] Those skilled in the art will appreciate that all or part of the processes in the methods for implementing the above embodiments can be accomplished by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include processes of the embodiments of the above methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0108] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0109] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A vehicle following control method, characterized in that: include: Obtain the driving information and future trajectory of the preceding vehicle; Obtaining a planning reference line for the self-vehicle when following the preceding vehicle based on the preceding vehicle's driving information and future trajectory; According to the planning reference line, an ST graph projection of the position of the preceding vehicle changing with time is obtained; According to the set following strategy and the ST diagram projection of the preceding vehicle, the following speed curve of the vehicle is determined.

2. The vehicle following control method according to claim 1, characterized in that: The obtaining of the driving information of the preceding vehicle and the future trajectory of the preceding vehicle includes: Get the planned trajectory of the preceding vehicle; If the planned trajectory of the preceding vehicle is obtained, the planned trajectory of the preceding vehicle is used as the future trajectory of the preceding vehicle; If the planned trajectory of the preceding vehicle is not obtained, the predicted trajectory of the preceding vehicle is obtained based on the driving information of the preceding vehicle, and the predicted trajectory is used as the future trajectory of the preceding vehicle. The driving information of the preceding vehicle includes at least the position, heading, speed, acceleration and yaw rate of the preceding vehicle.

3. The vehicle following control method according to claim 1, characterized in that: Obtaining a planning reference line for the vehicle following the preceding vehicle based on the preceding vehicle's driving information and future trajectory includes: Obtaining a historical path of the preceding vehicle based on the driving information of the preceding vehicle; A planning reference line of the vehicle is fitted based on the historical path of the preceding vehicle and the future trajectory.

4. The vehicle following control method according to any one of claims 1 to 3, characterized in that: Obtaining an ST graph projection of the position of the preceding vehicle changing with time according to the planned reference line includes: Establishing a curvilinear coordinate system according to the planning reference line; In the curvilinear coordinate system, the sl coordinates of the vehicle and the preceding vehicle are obtained; According to the sl coordinates of the preceding vehicle, an st graph projection of the preceding vehicle's position changing with time is obtained.

5. The vehicle following control method according to claim 4, characterized in that: The determining of the following speed curve of the vehicle according to the set following strategy and the ST graph projection of the preceding vehicle includes: According to the fixed-time-headroom following strategy, the expected following distance of the ego vehicle at time t is determined, where the expected following distance is: d t =v i,t THW+d safe , Among them, d t is the expected following distance, v i,t is the speed of the vehicle at time t, THW is the set time distance to follow the vehicle, d safe A safe parking distance; According to the position of the preceding vehicle at each moment, the expected position of the vehicle is obtained, where the expected position of the vehicle is: s d,t =s 1,t -d t , Among them, s d,t is the expected position of the vehicle at time t, s 1,t is the position of the rear end of the preceding vehicle at time t; According to the expected position of the ego vehicle at each moment, the following speed curve of the ego vehicle is determined.

6. The vehicle following control method according to claim 5, characterized in that: The method of determining the following speed curve of the vehicle according to the desired position of the vehicle at each moment includes: Construct the ST curve of the vehicle based on the expected position of the vehicle at each moment; The following speed curve of the own vehicle is solved based on the ST curve of the own vehicle.

7. A vehicle following control system, characterized in that: include: The acquisition module is used to obtain the driving information of the preceding vehicle and the future trajectory of the preceding vehicle; A reference line generation module is used to obtain a planning reference line when the vehicle follows the preceding vehicle based on the driving information and future trajectory of the preceding vehicle; A projection module, configured to obtain an ST graph projection of the position of the preceding vehicle changing with time based on the planned reference line; The control module is used to determine the following speed curve of the vehicle according to the set following strategy and the ST diagram projection of the preceding vehicle.

8. A vehicle, characterized in that: include: The vehicle following control system according to claim 7.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the vehicle following control method according to any one of claims 1 to 6 is implemented.

10. A computer-readable storage medium comprising a memory and a computer program stored in the memory and executable on a processor, characterized in that: When the program is executed by a processor, the vehicle following control method according to any one of claims 1 to 6 is implemented.

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