Lane change trajectory acquisition method, device, computer equipment, medium and program product

Abstract

The present application relates to a lane-changing trajectory acquisition method, apparatus, computer equipment, storage medium and computer program product. A target coordinate system is established with the center line of a vehicle's driving lane as the S axis and a line perpendicular to the vehicle's driving lane as the L axis. A trajectory is calculated based on the origin coordinates as the lane-changing starting point and the L-axis coordinates of the lane-changing end point in a lane adjacent to the vehicle's driving lane to obtain an initial lane-changing trajectory. Then, the terminal S-axis coordinates corresponding to the terminal trajectory of a preset length at the end of the initial lane-changing trajectory are obtained, and the terminal S-axis coordinates of the terminal trajectory in the initial lane-changing trajectory are attenuated to finally obtain a target lane-changing trajectory. In an intelligent driving scenario, the lane-changing trajectory end can be guaranteed to be smooth, and the smoothness of the lane-changing trajectory is greatly improved. While achieving fast lane changing, it is guaranteed that the vehicle can smoothly drive to the center of the lane after entering the target lane.

Description

Technical Field

[0001] The present application relates to the field of intelligent driving, and in particular to a lane change trajectory acquisition method, device, computer equipment, medium and program product. Background Art

[0002] The curvature of the lane-changing trajectory directly affects the centripetal acceleration of the vehicle during the lane-changing process. The centripetal acceleration not only affects the driver's comfort, but also has a certain impact on the vehicle's safety performance. Excessive lateral acceleration will cause the vehicle to roll over. The curvature change rate of the lane-changing trajectory greatly affects the tracking error of the trajectory tracking module. Excessive curvature change rate will make it difficult for the trajectory tracking module to track the lane-changing trajectory at a small error level.

[0003] Existing trajectory tracking algorithms usually use polynomial trajectory methods to ensure the smoothness of the lane change curve and the curvature change rate. However, the dynamic performance of commercial vehicles is poor, and it is difficult to ensure that the trajectory tracking module can achieve lane change trajectory tracking at a small error level. In order to solve this problem, it is often necessary to increase the length of the lane change process to make the lane change process smoother, thereby reducing the difficulty of trajectory tracking.

[0004] However, increasing the lane-changing time will increase the time vehicles spend riding the lane, which will have an adverse effect on traffic flow. Summary of the invention

[0005] Based on this, it is necessary to provide a lane changing trajectory acquisition method, device, computer equipment, medium and program product that can realize fast and smooth lane changing of vehicles in response to the above technical problems.

[0006] In a first aspect, the present application provides a lane change trajectory acquisition method, the method comprising:

[0007] The target coordinate system is established with the center line of the vehicle lane as the S axis and the line perpendicular to the vehicle lane as the L axis;

[0008] Acquire lane-changing coordinate information, the lane-changing coordinate information including an origin coordinate as a lane-changing starting point and an L-axis coordinate of a lane-changing end point in a lane adjacent to the vehicle driving lane;

[0009] Calculate the trajectory based on the lane-changing coordinate information to obtain an initial lane-changing trajectory;

[0010] Obtaining a terminal trajectory of a preset length at the end of the initial lane-changing trajectory and a terminal S-axis coordinate corresponding to the terminal trajectory;

[0011] The terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory is attenuated to obtain the target lane-changing trajectory.

[0012] In one embodiment, the above-mentioned trajectory calculation based on the lane change coordinate information to obtain the initial lane change trajectory includes:

[0013] Constructing a preset trajectory expression with the S-axis coordinate as an independent variable and the L-axis coordinate as a dependent variable, wherein the preset trajectory expression includes a plurality of first coefficients and a plurality of second coefficients;

[0014] Determining values ​​of a plurality of first coefficients according to the origin coordinates as the lane change starting point and the L-axis coordinates of the lane change end point;

[0015] Calculating values ​​of a plurality of second coefficients according to the vehicle driving data, the L-axis coordinate of the lane change end point, and the preset lane change duration;

[0016] Substitute the values ​​of the multiple first coefficients and the values ​​of the multiple second coefficients into the preset trajectory expression to obtain an initial lane changing trajectory.

[0017] In one embodiment, the attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain the target lane-changing trajectory includes:

[0018] Performing attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain an attenuated S-axis coordinate;

[0019] Based on the preset trajectory expression and the attenuated S-axis coordinate, the L-axis coordinate of the terminal trajectory is calculated, and the target lane changing trajectory is obtained according to the attenuated S-axis coordinate and L-axis coordinate of the terminal trajectory.

[0020] In one embodiment, the attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain the attenuated S-axis coordinate includes:

[0021] Determine the S-axis coordinate of the terminal initial point in the terminal trajectory;

[0022] Determine the difference between the S-axis coordinates of each trajectory point after the terminal initial point in the terminal trajectory and the S-axis coordinates of the terminal initial point;

[0023] An exponential decay process is performed based on the difference and the S-axis coordinate of the terminal initial point to obtain the decayed S-axis coordinate of each trajectory point after the terminal initial point.

[0024] In one embodiment, the method further comprises:

[0025] Determine whether the trajectory trend of the target lane-changing trajectory meets the target accuracy requirement;

[0026] If not, the S-axis coordinate of the lane-changing end point in the target lane-changing trajectory is obtained;

[0027] Filtering the S-axis coordinate of the lane-changing end point to obtain the filtered S-axis coordinate of the lane-changing end point;

[0028] If the filtered S-axis coordinate of the lane change end point does not meet the target accuracy requirement, the filtering process is continued until the filtered S-axis coordinate of the lane change end point meets the target accuracy requirement.

[0029] In one embodiment, filtering the S-axis coordinate of the lane change endpoint to obtain the filtered S-axis coordinate of the lane change endpoint includes:

[0030] Obtain the coordinate error between the S-axis coordinate of the lane change end point and the S-axis coordinate of the target position;

[0031] The coordinate error is filtered according to a preset filter coefficient to obtain the filtered S-axis coordinate of the lane change endpoint.

[0032] In a second aspect, the present application further provides a lane change trajectory acquisition device, the device comprising:

[0033] A coordinate system establishment module is used to establish a target coordinate system with the center line of the vehicle lane as the S axis and the line perpendicular to the vehicle lane as the L axis;

[0034] A coordinate acquisition module, used to acquire lane change coordinate information, the lane change coordinate information including an origin coordinate as a lane change starting point and an L-axis coordinate of a lane change end point in a lane adjacent to the vehicle driving lane;

[0035] A trajectory calculation module, used to perform trajectory calculation based on the lane-changing coordinate information to obtain an initial lane-changing trajectory;

[0036] An end acquisition module is used to acquire an end trajectory of a preset length at the end of the initial lane-changing trajectory, and an end S-axis coordinate corresponding to the end trajectory;

[0037] The trajectory acquisition module is used to perform attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain the target lane-changing trajectory.

[0038] In a third aspect, the present application further provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor implements any one of the method steps in the first aspect when executing the computer program.

[0039] In a fourth aspect, the present application further provides a computer-readable storage medium, wherein a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the method steps of any one of the first aspects are implemented.

[0040] In a fifth aspect, the present application further provides a computer program product, including a computer program, which implements any one of the method steps in the first aspect when executed by a processor.

[0041] The lane changing trajectory acquisition method, device, computer equipment, storage medium and computer program product above establish a target coordinate system with the center line of the vehicle's driving lane as the S axis and the line perpendicular to the vehicle's driving lane as the L axis, and perform trajectory calculation based on the origin coordinates as the lane changing starting point and the L axis coordinates of the lane changing end point in the lane adjacent to the vehicle's driving lane to obtain an initial lane changing trajectory, and then obtain the terminal S axis coordinates corresponding to the terminal trajectory of a preset length at the end of the initial lane changing trajectory, and perform attenuation processing on the terminal S axis coordinates of the terminal trajectory in the initial lane changing trajectory to finally obtain the target lane changing trajectory. In the intelligent driving scenario, the lane changing trajectory end can be guaranteed to be smooth, and the smoothness of the lane changing trajectory can be greatly improved. While achieving fast lane changing, it is ensured that the vehicle can smoothly drive to the center of the lane after entering the target lane. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A diagram showing an application environment of a lane-changing trajectory acquisition method in one embodiment;

[0043] Figure 2 is a flow chart of a lane-changing trajectory acquisition method in one embodiment;

[0044] Figure 3 for Figure 2 A schematic diagram of the process flow of step S203 in the illustrated embodiment;

[0045] Figure 4 is a flow chart of a lane-changing trajectory acquisition method in one embodiment;

[0046] Figure 5 It is a schematic flow chart of a terminal attenuation lane-changing trajectory planning method in one embodiment;

[0047] Figure 6 for Figure 5 A schematic diagram of a lane-changing trajectory in the illustrated embodiment;

[0048] Figure 7 for Figure 5 A schematic diagram of the relationship between the coordinates after attenuation and the coordinates before attenuation in the embodiment shown;

[0049] Figure 8 for Figure 5 A comparison diagram of the trajectory after terminal attenuation and the standard trajectory in the embodiment shown;

[0050] Fig. 9 is a structural block diagram of a lane-changing trajectory acquisition device in one embodiment;

[0051] Fig.10 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0053] The lane change trajectory acquisition method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. Among them, the main control device 10 communicates with the measuring device 20 through the network. The data storage system can store the data that the measuring device 20 needs to process, and the data storage system is integrated on the measuring device 20. Among them, the measuring device 20 is used to measure the environmental data of the vehicle and send the environmental data to the main control device 10. The main control device 10 establishes a target coordinate system based on the environmental data measured by the measurement module, with the center line of the vehicle's driving lane as the S axis and the line perpendicular to the vehicle's driving lane as the L axis, and obtains the lane change coordinate information. Among them, the lane change coordinate information includes the origin coordinates as the starting point of the lane change, and the L axis coordinates of the lane change end point in the lane adjacent to the vehicle's driving lane. The main control device 10 is also used to calculate the trajectory based on the lane change coordinate information to obtain the initial lane change trajectory, and obtain the terminal trajectory of the preset length at the end of the initial lane change trajectory, and the terminal S axis coordinates corresponding to the terminal trajectory, and the terminal S axis coordinates of the terminal trajectory in the initial lane change trajectory are attenuated to obtain the target lane change trajectory. Among them, the main control device 10 can be a vehicle-mounted computing computer. The measuring device 20 includes a video camera 201 , a radar sensor 202 , a laser rangefinder 203 and other devices.

[0054] In one embodiment, Figure 2 As shown, a lane change trajectory acquisition method is provided, and the method is applied to Figure 1 Taking the master control device 10 in the example as an example, the method includes the following steps:

[0055] S201: Establish a target coordinate system with the center line of the vehicle lane as the S axis and the line perpendicular to the vehicle lane as the L axis.

[0056] The target coordinate system refers to the Frenet coordinate system. When defining the position of a spatial point, the Cartesian coordinate system is usually used. However, in actual applications, roads are often not "straight", so the coordinate position of the vehicle in the lane cannot be accurately defined based on the Cartesian coordinate system. In the Frenet coordinate system, the coordinate position of a point on the ground can be located by the longitudinal axis and the transverse axis, and the longitudinal axis is always the center line of the road and is not affected by the curvature of the road.

[0057] Among them, the establishment of the Frenet coordinate system is based on a given reference line (i.e., the center line of the vehicle's driving lane, denoted as the S axis). Assuming that the coordinates of the vehicle in the coordinate system are (x, y), a projection is made from the vehicle's position (x, y) to the reference line S axis, and the projection point is F. The distance between point F and the vehicle's position (x, y) is the lateral displacement d (i.e., the distance on the L axis), and the distance from the starting point of the reference line to the projection point F is the longitudinal displacement s (i.e., the distance on the S axis).

[0058] S202: Acquire lane-changing coordinate information, where the lane-changing coordinate information includes an origin coordinate as a lane-changing starting point and an L-axis coordinate of a lane-changing end point in a lane adjacent to the vehicle driving lane.

[0059] Among them, the origin coordinates are the coordinates of the starting position of the vehicle lane change on the vehicle's driving lane, which are regarded as the coordinates of the origin in the Frenet coordinate system. The lane change end point refers to a point on the center line of the lane adjacent to the vehicle's driving lane. When the vehicle moves from the center line of the vehicle's driving lane to the center line of the adjacent lane, the lane change is considered successful. Therefore, the L-axis coordinates of the lane change end point are known, that is, the distance between the center line of the vehicle's driving lane and the center line of the adjacent lane.

[0060] The lane change coordinate information can be obtained by measuring equipment, including video cameras, radar sensors, laser rangefinders and other devices. The video camera is used to identify moving objects, such as the vehicle in front; the radar sensor is used to scan the surrounding environment and present the scanning results in the form of a 3D map; the laser rangefinder is used to measure the lateral displacement of the vehicle to determine the vehicle position. The coordinate information of the vehicle is determined according to the vehicle position, specifically, the lateral position of the vehicle is the L-axis position, and the longitudinal position of the vehicle is the S-axis position.

[0061] S203: Calculate a trajectory based on the lane-changing coordinate information to obtain an initial lane-changing trajectory.

[0062] Among them, trajectory calculation refers to constructing the polynomial planning functions s(t) and d(s) of the lateral and longitudinal displacements. After obtaining the planning functions of the lateral and longitudinal displacements, time interpolation can be performed to obtain the trajectory points in the reference line Frenet coordinate system. Since both the lateral and longitudinal directions are obtained through high-order polynomial interpolation, the trajectory in this Frenet coordinate system is smooth. Specifically, taking the cubic polynomial trajectory and the quintic polynomial trajectory as examples, the cubic polynomial trajectory is obtained by specifying the initial and end state positions (q0, q1) and velocities (v0, v1), 4 conditions, and the expression is:

[0063] q(t)=a 0 +a 1 (tt 0 )+a 2 (tt0 ) 2 +a 3 (tt 0 ) 3 ,t 0 ≤t≤t 1

[0064] Solving for each coefficient is:

[0065]

[0066] Among them, t 0 represents the lane change start time; t represents the current lane change time; t 1 Indicates the lane change end time; v 0 Indicates the speed of the vehicle at the lane change origin; v 1 Indicates the speed at the end of the lane change; h = q 1 -q 0 (q 1 The angle of the lane change end point, q 0 represents the angle of the lane change origin); T represents the lane change duration.

[0067] Therefore, the corresponding L-axis coordinate is calculated according to the S-axis coordinate of the trajectory point, thus obtaining the lane change trajectory. However, since the trajectory planned by the cubic polynomial has a continuous path and velocity curve, the acceleration is step-like. In order to obtain a trajectory with continuous acceleration, the position and velocity require appropriate initial and terminal conditions, as well as appropriate initial and terminal acceleration values. There are a total of six boundary conditions, so a quintic polynomial is required:

[0068] q(t)=a 0 +a 1 (tt 0 )+a 2 (tt 0 ) 2 +a 3 (tt 0 ) 3 +a 4 (tt 0 ) 4 +a 5 (tt 0 ) 5

[0069] in:

[0070] q(t 0 )=q 0 ,q(t 1 )=q 1

[0071]

[0072] Among them, t 0 represents the lane change start time; t represents the current lane change time; t 1 Indicates the lane change end time; v 0 Indicates the speed of the vehicle at the lane change origin; v 1 Indicates the speed at the end of lane change; q 1 Indicates the angle of the lane change end point; q 0 Indicates the angle of the lane change origin; a i represents the polynomial coefficient; a i represents acceleration;

[0073] Define T = t 1 -t 0 , then the polynomial coefficients are solved as:

[0074]

[0075] S204: Obtaining a terminal trajectory of a preset length at the terminal of the initial lane-changing trajectory and a terminal S-axis coordinate corresponding to the terminal trajectory.

[0076] Among them, the preset length can be set according to the actual application needs. For example, it can be a trajectory of 40% of the length of the end of the lane changing trajectory. The terminal S-axis coordinate refers to the S-axis coordinate of each trajectory point on the terminal trajectory. Since the L-axis coordinate represents the horizontal distance between the corresponding trajectory point and the lane changing starting point, it is equivalent to the lane changing progress. In order to process the smoothness of the terminal trajectory, it can only be done through the S-axis coordinate. Therefore, it is necessary to obtain the S-axis coordinate corresponding to each trajectory point on the terminal trajectory.

[0077] S205: performing attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain a target lane-changing trajectory.

[0078] Among them, the attenuation processing can extend the trajectory length without changing the smoothness of the initial lane-changing trajectory of the polynomial planning, making the terminal trajectory smoother. Specifically, assuming that the coordinates of a certain trajectory point on the terminal trajectory are (S0, L0), if the coordinates of the point can be changed to (S0+x, L0) while ensuring the smoothness of the trajectory, where x is a positive number greater than zero, the new trajectory point will be smoother than the original trajectory point. In this way, the S coordinates of all trajectory points on the terminal trajectory are translated backward through the main control device, and the terminal trajectory will become smoother as a whole.

[0079] In the above lane changing trajectory acquisition method, a target coordinate system is established with the center line of the vehicle's driving lane as the S axis and the line perpendicular to the vehicle's driving lane as the L axis. The trajectory is calculated based on the origin coordinates as the lane changing starting point and the L axis coordinates of the lane changing end point in the lane adjacent to the vehicle's driving lane to obtain an initial lane changing trajectory. Then, the terminal S axis coordinates corresponding to the terminal trajectory of a preset length at the end of the initial lane changing trajectory are obtained, and the terminal S axis coordinates of the terminal trajectory in the initial lane changing trajectory are attenuated to finally obtain the target lane changing trajectory. In the intelligent driving scenario, the smoothness of the lane changing trajectory end can be guaranteed, which greatly improves the smoothness of the lane changing trajectory. While achieving fast lane changing, it can ensure that the vehicle can smoothly drive to the center of the lane after entering the target lane.

[0080] In one embodiment, Figure 3 As shown, the above trajectory calculation based on the lane change coordinate information to obtain the initial lane change trajectory includes:

[0081] S301: constructing a preset trajectory expression with the S-axis coordinate as an independent variable and the L-axis coordinate as a dependent variable, wherein the preset trajectory expression includes a plurality of first coefficients and a plurality of second coefficients.

[0082] Among them, when using a quintic polynomial to calculate the trajectory, since six boundary conditions are involved, the polynomial coefficients are relatively complex. Therefore, when applying it, the quintic polynomial is simplified, the initial and terminal conditions of the position and velocity are represented by the initial orientation angle and the terminal orientation angle of the vehicle, and the initial and terminal acceleration values ​​are represented by the rate of change of the initial orientation angle and the rate of change of the terminal orientation angle of the vehicle. The preset trajectory expression can be expressed as:

[0083] L = a 0 +a 1 ×s+a 2 ×s 2 +a 3 ×s 3 +a 4 ×s 4 +a 5 ×s 5

[0084] Among them, s represents the distance between the S-axis coordinate and the origin, a 0 Indicates the starting position of the vehicle changing lanes, i.e. the origin coordinate; a 1 represents the first-order derivative of the L coordinate at the origin, that is, the speed corresponding to the L coordinate, which is calculated by the initial heading angle and the final heading angle of the vehicle; a 2 represents the second-order derivative of the L coordinate at the origin, that is, the acceleration corresponding to the L coordinate, and the rate of change of the initial orientation angle and the rate of change of the terminal orientation angle of the vehicle. Therefore, the multiple first coefficients include a 0 、a 1and a 2 , which means that it can be directly obtained from the relevant data of the vehicle's heading angle, while the second coefficient cannot be directly obtained, including a 3 、a 4 and a 5 .

[0085] S302: Determine values ​​of a plurality of first coefficients according to the origin coordinates of the lane change start point and the L-axis coordinates of the lane change end point.

[0086] Among them, from the origin coordinates of the lane change starting point, it can be seen that when the vehicle is at the origin, the center line of the vehicle coincides with the center line of the vehicle's driving lane, the initial heading angle is zero, and the rate of change of the initial heading angle is also zero. When the lane change is completed, the center line of the vehicle coincides with the center line of the target lane, so the terminal heading angle is zero, and the rate of change of the terminal heading angle is also zero. Therefore, a 0 =0, a 1 =0, a 2 =0.

[0087] S303: Calculate the values ​​of a plurality of second coefficients according to the vehicle driving data, the L-axis coordinate of the lane change endpoint, and the preset lane change duration.

[0088] The vehicle driving data refers to the vehicle speed, and the L-axis coordinate of the lane change end point is used to calculate the distance between the center line of the lane at the lane change end point and the center line of the vehicle driving lane, that is, the distance of the lane change trajectory on the L-axis. Therefore, the calculation formula for obtaining multiple second coefficients is:

[0089]

[0090] Where w is the distance of the lane change trajectory on the L axis, v x is the vehicle speed, T is the preset lane changing time, and the value of T can be adjusted. The larger T is, the longer the lane changing time is and the smoother the lane changing trajectory is.

[0091] S304: Substitute the values ​​of the plurality of first coefficients and the values ​​of the plurality of second coefficients into a preset trajectory expression to obtain an initial lane-changing trajectory.

[0092] Among them, a preset lane changing duration is set for the preset trajectory expression. At a certain trajectory point, the main control device calculates the coordinate of the L axis according to the current vehicle speed and the distance of the lane changing trajectory on the L axis, thereby obtaining a series of trajectory points as the initial lane changing trajectory.

[0093] In this embodiment, by constructing a preset trajectory expression with the S-axis coordinate as the independent variable and the L-axis coordinate as the dependent variable, and determining the parameters of the preset trajectory expression according to the origin coordinate as the lane change starting point and the L-axis coordinate as the lane change end point, according to the vehicle driving data, and parameters such as the preset lane change duration, the initial lane change trajectory can be accurately obtained, providing the corresponding coordinates for the subsequent terminal trajectory attenuation processing.

[0094] In one embodiment, the above-mentioned attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory to obtain the target lane changing trajectory includes: attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory to obtain the attenuated S-axis coordinate; based on a preset trajectory expression and the attenuated S-axis coordinate, calculating the L-axis coordinate of the terminal trajectory, and obtaining the target lane changing trajectory according to the attenuated S-axis coordinate and the L-axis coordinate of the terminal trajectory.

[0095] Among them, the attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory is equivalent to moving the terminal S-axis coordinate backward and extending the length of the terminal trajectory. Specifically, the main control device performs exponential function attenuation processing on the terminal S-axis coordinate to avoid excessive attenuation resulting in excessive deviation between the terminal trajectory and the lane-changing trajectory before the decay starting point, thereby affecting the smoothness of the lane-changing trajectory. The S-axis coordinate after decay is re-substituted into the preset trajectory expression to calculate the corresponding L-axis coordinate to obtain the target lane-changing trajectory.

[0096] In this embodiment, the target lane changing trajectory is obtained by decaying the S-axis coordinates of the terminal trajectory and calculating the corresponding L-axis coordinates based on the decayed S-axis coordinates. The terminal trajectory can be further processed on the basis of maintaining the original smoothness of the polynomial planning trajectory to reduce the error of trajectory planning.

[0097] In one embodiment, Figure 4 As shown, the above-mentioned attenuation processing is performed on the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain the attenuated S-axis coordinate, including:

[0098] S401: Determine the S-axis coordinate of the terminal initial point in the terminal trajectory.

[0099] The end initial point is the coordinate point where decay begins, and from this point on, all subsequent S-axis coordinates are decayed.

[0100] S402: Determine the S-axis coordinates of each track point after the terminal initial point in the terminal track, and the differences between the S-axis coordinates of the terminal initial point and each of them.

[0101] When performing exponential decay processing, the exponential calculation is performed based on the difference between the coordinates of the decay point and the coordinates of the decay starting point. Therefore, it is necessary to obtain the S-axis coordinates of all trajectory points that need to decay after the decay starting point in the terminal trajectory.

[0102] S403: Perform exponential decay processing according to the difference and the S-axis coordinate of the terminal initial point to obtain the decayed S-axis coordinate of each trajectory point after the terminal initial point.

[0103] The master control device performs exponential calculation based on the difference between the S-axis coordinates of all trajectory points that need to decay after the decay starting point in the terminal trajectory and the S coordinate of the decay starting point, which can be expressed as:

[0104]

[0105] Among them, S 1 Represents the S-axis coordinate of the trajectory point after decay, S 0 represents the S coordinate of the trajectory point before decay, S t represents the S coordinate of the decay starting point, v x represents the vehicle speed, and T represents the preset lane change time.

[0106] In this embodiment, the decayed S coordinate is obtained by performing exponential calculation on the difference between the S-axis coordinates of each trajectory point after the terminal initial point in the terminal trajectory and the S-axis coordinates of the terminal initial point. This can further process the terminal trajectory on the basis of maintaining the original smoothness of the polynomial planning trajectory, thereby reducing the error of trajectory planning.

[0107] In one embodiment, the lane change trajectory acquisition method further includes: determining whether the trajectory trend of the target lane change trajectory meets the target accuracy requirement; if not, obtaining the S-axis coordinate of the lane change endpoint in the target lane change trajectory; filtering the S-axis coordinate of the lane change endpoint to obtain the filtered S-axis coordinate of the lane change endpoint; if the filtered S-axis coordinate of the lane change endpoint does not meet the target accuracy requirement, continuing the filtering process until the filtered S-axis coordinate of the lane change endpoint meets the target accuracy requirement.

[0108] Among them, in actual application, the L-axis coordinate of the terminal trajectory is calculated based on the S-axis coordinate after decay. When the S-axis coordinate reaches a certain size, the L-axis coordinate is infinitely close to the center line of the target lane change lane, but it does not completely overlap. Therefore, the target accuracy requirement refers to whether the end point of the lane change trajectory reaches the expected ideal position, that is, whether the distance of the L-axis coordinate of the lane change end point from the lane change origin on the L-axis is consistent with the distance of the center line of the target lane change trajectory from the lane change origin on the L-axis. If the accuracy requirement is not met, the coordinates of the lane change end point need to be filtered so that the error between the filtered L-axis coordinate of the end point and the target position is small enough.

[0109] In this embodiment, the accuracy of the lane changing trajectory can be guaranteed by judging whether the trajectory trend of the target lane changing trajectory meets the target accuracy requirement, and filtering the S-axis coordinate of the lane changing endpoint when it does not meet the target accuracy requirement, until the trajectory trend of the target lane changing trajectory meets the target accuracy requirement.

[0110] In one embodiment, the above-mentioned filtering processing of the S-axis coordinates of the lane change end point to obtain the filtered S-axis coordinates of the lane change end point includes: obtaining the coordinate error between the S-axis coordinates of the lane change end point and the S-axis coordinates of the target position; filtering the coordinate error according to a preset filtering coefficient to obtain the filtered S-axis coordinates of the lane change end point.

[0111] Among them, the preset filter coefficient is the filter coefficient of the first-order filter, and filtering the coordinate error according to the preset filter coefficient is to perform a smoothing process on the coordinate error, and the formula is:

[0112] dy(k+1)=(1-k)×[dy(k)-0]+k×0

[0113] Wherein, k is the filter coefficient, dy(k) is the error value at time k, and dy(k+1) is the error value at time k+1.

[0114] In this embodiment, the accuracy of the lane changing trajectory can be ensured by filtering the coordinate error between the S-axis coordinate of the lane changing end point and the S-axis coordinate of the target position.

[0115] In one embodiment, Figure 5 As shown, a terminal attenuation lane change trajectory planning method is provided.

[0116] (1) The centerline of the lane is used as the horizontal axis of the coordinate system, that is, the S axis. For any point on the non-lane line, its coordinates are determined as follows: a perpendicular line is drawn from the point to the lane centerline. The length of the intersection with the lane centerline from the starting point is the S coordinate value, and the length from the point on the perpendicular line to the intersection with the lane centerline is the L coordinate value.

[0117] (2) In the SL coordinate system, a fifth-order polynomial trajectory is calculated based on the lane-changing time length T; the trajectory extends from the origin of the center line of the lane at time 0 to the center line of the adjacent lane at time T. The fifth-order polynomial describes the trajectory as follows:

[0118] L = a 0 +a 1 ×s+a 2 ×s 2 +a 3 ×s 3 +a 4 ×s 4 +a5 ×s 5 (1)

[0119] Among them, a 0 =0, a 1 =0, a 2 =0,

[0120]

[0121] Among them, s represents the distance between the S-axis coordinate and the origin, w is the distance of the lane change trajectory on the L-axis, and v x is the vehicle speed, and T is the preset lane change time.

[0122] Assume that the vehicle speed is 20m / s, the lane change time T is set to 5s, and the width from the center line of the lane to the center line of the adjacent lane is 3.75m. The lane change trajectory obtained according to the above quintic polynomial is as follows: Figure 6 shown.

[0123] (3) Set the terminal length and perform attenuation processing on the terminal trajectory to achieve smooth lane change. The S coordinate attenuation formula is:

[0124] S1=S(S <St)

[0125]

[0126] for Figure 6 The obtained lane-changing trajectory is subjected to attenuation processing on the terminal trajectory, and S1 is used as the new S-axis coordinate value and substituted into equation (1) to obtain a new lane-changing trajectory. Among them, the comparison relationship between the coordinate S1 after attenuation and the coordinate S before attenuation is as follows: Figure 7 As shown; the new lane-changing trajectory after terminal attenuation is Figure 6 The contrast relationship between lane-changing trajectories in Figure 8 shown.

[0127] In this embodiment, by combining a quintic polynomial and attenuating the terminal trajectory, the final lane-changing trajectory after attenuation is obtained, thereby achieving trajectory planning for fast and smooth lane changes.

[0128] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0129] Based on the same inventive concept, the embodiment of the present application also provides a lane-changing trajectory acquisition device for implementing the lane-changing trajectory acquisition method involved above. The implementation solution provided by the device to solve the problem is similar to the implementation solution recorded in the above method, so the specific limitations in one or more lane-changing trajectory acquisition device embodiments provided below can refer to the limitations of the lane-changing trajectory acquisition method above, and will not be repeated here.

[0130] In one embodiment, Fig. 9 As shown, a lane change trajectory acquisition device is provided, including: a coordinate system establishment module 901, a coordinate acquisition module 902, a trajectory calculation module 903, a terminal acquisition module 904 and a trajectory acquisition module 905, wherein:

[0131] A coordinate system establishing module 901 is used to establish a target coordinate system with the center line of the vehicle driving lane as the S axis and the line perpendicular to the vehicle driving lane as the L axis;

[0132] A coordinate acquisition module 902 is used to acquire lane change coordinate information, where the lane change coordinate information includes an origin coordinate as a lane change start point and an L-axis coordinate of a lane change end point in a lane adjacent to the vehicle driving lane;

[0133] A trajectory calculation module 903 is used to perform trajectory calculation based on the lane-changing coordinate information to obtain an initial lane-changing trajectory;

[0134] The terminal acquisition module 904 is used to acquire a terminal trajectory of a preset length at the end of the initial lane-changing trajectory and a terminal S-axis coordinate corresponding to the terminal trajectory;

[0135] The trajectory acquisition module 905 is used to perform attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain a target lane-changing trajectory.

[0136] In one embodiment, the trajectory calculation module 903 includes: an expression building unit, a first coefficient determination unit, a second coefficient determination unit and an initial trajectory acquisition unit, wherein:

[0137] An expression construction unit, used to construct a preset trajectory expression with the S-axis coordinate as an independent variable and the L-axis coordinate as a dependent variable, wherein the preset trajectory expression includes a plurality of first coefficients and a plurality of second coefficients;

[0138] A first coefficient determination unit, configured to determine values ​​of a plurality of first coefficients according to the origin coordinates as the lane change start point and the L-axis coordinates of the lane change end point;

[0139] A second coefficient determination unit, configured to calculate a plurality of second coefficient values ​​according to the vehicle driving data, the L-axis coordinate of the lane change end point, and a preset lane change duration;

[0140] The initial trajectory acquisition unit is used to substitute the values ​​of the plurality of first coefficients and the values ​​of the plurality of second coefficients into a preset trajectory expression to obtain an initial lane-changing trajectory.

[0141] In one embodiment, the trajectory acquisition module 905 includes: an attenuation processing unit and a target trajectory acquisition unit, wherein:

[0142] an attenuation processing unit, used for performing attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane-changing trajectory to obtain an attenuated S-axis coordinate;

[0143] The target trajectory acquisition unit is used to calculate the L-axis coordinate of the terminal trajectory based on the preset trajectory expression and the attenuated S-axis coordinate, and obtain the target lane changing trajectory according to the attenuated S-axis coordinate and L-axis coordinate of the terminal trajectory.

[0144] In one embodiment, the attenuation processing unit includes: a coordinate determination unit, a difference acquisition unit and an attenuation processing unit, wherein:

[0145] A coordinate determination unit, used to determine the S-axis coordinate of the terminal initial point in the terminal trajectory;

[0146] A difference acquisition unit, used to determine the difference between the S-axis coordinates of each track point after the terminal initial point in the terminal track and the S-axis coordinates of the terminal initial point;

[0147] The attenuation processing unit is used to perform exponential attenuation processing according to the difference and the S-axis coordinate of the terminal initial point to obtain the attenuated S-axis coordinate of each trajectory point after the terminal initial point.

[0148] In one embodiment, the trajectory acquisition module 905 is also used to determine whether the trajectory trend of the target lane changing trajectory meets the target accuracy requirement; if not, the S-axis coordinate of the lane changing end point in the target lane changing trajectory is obtained; the S-axis coordinate of the lane changing end point is filtered to obtain the filtered S-axis coordinate of the lane changing end point; if the filtered S-axis coordinate of the lane changing end point does not meet the target accuracy requirement, the filtering process is continued until the filtered S-axis coordinate of the lane changing end point meets the target accuracy requirement.

[0149] In one embodiment, the trajectory acquisition module 905 is further used to obtain the coordinate error between the S-axis coordinate of the lane change endpoint and the S-axis coordinate of the target position; the coordinate error is filtered according to a preset filter coefficient to obtain the filtered S-axis coordinate of the lane change endpoint.

[0150] Each module in the lane change trajectory acquisition device can be implemented in whole or in part by software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0151] In one embodiment, a computer device is provided. The computer device may be the main control device in the above embodiment. The internal structure diagram thereof may be as follows: Fig.10 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface, the display unit and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for acquiring a lane change trajectory is implemented. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device shell, or an external keyboard, touchpad or mouse.

[0152] Those skilled in the art will understand that Fig.10 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0153] In one embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the following steps when executing the computer program: establishing a target coordinate system with a center line of a vehicle driving lane as an S axis and a line perpendicular to the vehicle driving lane as an L axis; obtaining lane change coordinate information, wherein the lane change coordinate information includes an origin coordinate as a lane change starting point and an L axis coordinate of a lane change end point in a lane adjacent to the vehicle driving lane; performing trajectory calculation based on the lane change coordinate information to obtain an initial lane change trajectory; obtaining an end trajectory of a preset length at the end of the initial lane change trajectory and an end S axis coordinate corresponding to the end trajectory; and performing attenuation processing on the end S axis coordinate of the end trajectory in the initial lane change trajectory to obtain a target lane change trajectory.

[0154] In one embodiment, when a processor executes a computer program, trajectory calculation based on lane change coordinate information is performed to obtain an initial lane change trajectory, including: constructing a preset trajectory expression with S-axis coordinates as an independent variable and L-axis coordinates as a dependent variable, the preset trajectory expression including multiple first coefficients and multiple second coefficients; determining values ​​of the multiple first coefficients based on the origin coordinates as the lane change starting point and the L-axis coordinates of the lane change end point; calculating values ​​of the multiple second coefficients based on vehicle driving data, the L-axis coordinates of the lane change end point, and a preset lane change duration; substituting the values ​​of the multiple first coefficients and the values ​​of the multiple second coefficients into the preset trajectory expression to obtain the initial lane change trajectory.

[0155] In one embodiment, the processor executes a computer program involving performing attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory to obtain a target lane changing trajectory, including: performing attenuation processing on the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory to obtain an attenuated S-axis coordinate; calculating the L-axis coordinate of the terminal trajectory based on a preset trajectory expression and the attenuated S-axis coordinate, and obtaining the target lane changing trajectory based on the attenuated S-axis coordinate and the L-axis coordinate of the terminal trajectory.

[0156] In one embodiment, when the processor executes a computer program, the attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane change trajectory is involved to obtain the attenuated S-axis coordinate, including: determining the S-axis coordinate of the terminal initial point in the terminal trajectory; determining the S-axis coordinates of each trajectory point after the terminal initial point in the terminal trajectory, and the differences between the S-axis coordinates of the terminal initial point and the S-axis coordinates of the terminal initial point; performing exponential attenuation processing according to the differences and the S-axis coordinate of the terminal initial point to obtain the attenuated S-axis coordinates of each trajectory point after the terminal initial point.

[0157] In one embodiment, the processor further implements the following steps when executing the computer program: determining whether the trajectory trend of the target lane change trajectory meets the target accuracy requirement; if not, obtaining the S-axis coordinate of the lane change end point in the target lane change trajectory; filtering the S-axis coordinate of the lane change end point to obtain the filtered S-axis coordinate of the lane change end point; if the filtered S-axis coordinate of the lane change end point does not meet the target accuracy requirement, continuing the filtering process until the filtered S-axis coordinate of the lane change end point meets the target accuracy requirement.

[0158] In one embodiment, when a processor executes a computer program, filtering is performed on the S-axis coordinate of the lane change endpoint to obtain the filtered S-axis coordinate of the lane change endpoint, including: obtaining the coordinate error between the S-axis coordinate of the lane change endpoint and the S-axis coordinate of the target position; filtering the coordinate error according to a preset filtering coefficient to obtain the filtered S-axis coordinate of the lane change endpoint.

[0159] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented: a target coordinate system is established with a center line of a vehicle driving lane as an S axis and a line perpendicular to the vehicle driving lane as an L axis; lane change coordinate information is obtained, the lane change coordinate information includes an origin coordinate as a lane change starting point, and an L-axis coordinate of a lane change end point in a lane adjacent to the vehicle driving lane; trajectory calculation is performed based on the lane change coordinate information to obtain an initial lane change trajectory; an end trajectory of a preset length at the end of the initial lane change trajectory and an end S-axis coordinate corresponding to the end trajectory are obtained; and the end S-axis coordinate of the end trajectory in the initial lane change trajectory is attenuated to obtain a target lane change trajectory.

[0160] In one embodiment, when a computer program is executed by a processor, trajectory calculation based on lane change coordinate information is performed to obtain an initial lane change trajectory, including: constructing a preset trajectory expression with S-axis coordinates as an independent variable and L-axis coordinates as a dependent variable, the preset trajectory expression including multiple first coefficients and multiple second coefficients; determining values ​​of the multiple first coefficients based on the origin coordinates as the lane change starting point and the L-axis coordinates of the lane change end point; calculating values ​​of the multiple second coefficients based on vehicle driving data, the L-axis coordinates of the lane change end point, and a preset lane change duration; substituting the values ​​of the multiple first coefficients and the values ​​of the multiple second coefficients into the preset trajectory expression to obtain an initial lane change trajectory.

[0161] In one embodiment, when the computer program is executed by a processor, the attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory is involved to obtain a target lane changing trajectory, including: attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory to obtain an attenuated S-axis coordinate; based on a preset trajectory expression and the attenuated S-axis coordinate, calculating the L-axis coordinate of the terminal trajectory, and obtaining the target lane changing trajectory according to the attenuated S-axis coordinate and the L-axis coordinate of the terminal trajectory.

[0162] In one embodiment, when a computer program is executed by a processor, the computer program involves performing attenuation processing on the terminal S-axis coordinates of the terminal trajectory in the initial lane change trajectory to obtain the attenuated S-axis coordinates, including: determining the S-axis coordinates of the terminal initial point in the terminal trajectory; determining the S-axis coordinates of each trajectory point after the terminal initial point in the terminal trajectory, and the differences between the S-axis coordinates of the terminal initial point and the S-axis coordinates of the terminal initial point; performing exponential attenuation processing according to the differences and the S-axis coordinates of the terminal initial point to obtain the attenuated S-axis coordinates of each trajectory point after the terminal initial point.

[0163] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: determining whether the trajectory trend of the target lane change trajectory meets the target accuracy requirement; if not, obtaining the S-axis coordinate of the lane change end point in the target lane change trajectory; filtering the S-axis coordinate of the lane change end point to obtain the filtered S-axis coordinate of the lane change end point; if the filtered S-axis coordinate of the lane change end point does not meet the target accuracy requirement, continuing the filtering process until the filtered S-axis coordinate of the lane change end point meets the target accuracy requirement.

[0164] In one embodiment, when a computer program is executed by a processor, the filtering process involved in filtering the S-axis coordinate of the lane change endpoint to obtain the filtered S-axis coordinate of the lane change endpoint includes: obtaining the coordinate error between the S-axis coordinate of the lane change endpoint and the S-axis coordinate of the target position; filtering the coordinate error according to a preset filtering coefficient to obtain the filtered S-axis coordinate of the lane change endpoint.

[0165] In one embodiment, a computer program product is provided, including a computer program, which implements the following steps when executed by a processor: establishing a target coordinate system with the center line of a vehicle driving lane as the S axis and a line perpendicular to the vehicle driving lane as the L axis; obtaining lane change coordinate information, the lane change coordinate information including the origin coordinates as the lane change starting point and the L axis coordinates of the lane change end point in the lane adjacent to the vehicle driving lane; performing trajectory calculation based on the lane change coordinate information to obtain an initial lane change trajectory; obtaining an end trajectory of a preset length at the end of the initial lane change trajectory and the end S axis coordinates corresponding to the end trajectory; and performing attenuation processing on the end S axis coordinates of the end trajectory in the initial lane change trajectory to obtain a target lane change trajectory.

[0166] In one embodiment, when a computer program is executed by a processor, trajectory calculation based on lane change coordinate information is performed to obtain an initial lane change trajectory, including: constructing a preset trajectory expression with S-axis coordinates as an independent variable and L-axis coordinates as a dependent variable, the preset trajectory expression including multiple first coefficients and multiple second coefficients; determining values ​​of the multiple first coefficients based on the origin coordinates as the lane change starting point and the L-axis coordinates of the lane change end point; calculating values ​​of the multiple second coefficients based on vehicle driving data, the L-axis coordinates of the lane change end point, and a preset lane change duration; substituting the values ​​of the multiple first coefficients and the values ​​of the multiple second coefficients into the preset trajectory expression to obtain an initial lane change trajectory.

[0167] In one embodiment, when the computer program is executed by a processor, the attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory is involved to obtain a target lane changing trajectory, including: attenuation processing of the terminal S-axis coordinate of the terminal trajectory in the initial lane changing trajectory to obtain an attenuated S-axis coordinate; based on a preset trajectory expression and the attenuated S-axis coordinate, calculating the L-axis coordinate of the terminal trajectory, and obtaining the target lane changing trajectory according to the attenuated S-axis coordinate and the L-axis coordinate of the terminal trajectory.

[0168] In one embodiment, when a computer program is executed by a processor, the computer program involves performing attenuation processing on the terminal S-axis coordinates of the terminal trajectory in the initial lane change trajectory to obtain the attenuated S-axis coordinates, including: determining the S-axis coordinates of the terminal initial point in the terminal trajectory; determining the S-axis coordinates of each trajectory point after the terminal initial point in the terminal trajectory, and the differences between the S-axis coordinates of the terminal initial point and the S-axis coordinates of the terminal initial point; performing exponential attenuation processing according to the differences and the S-axis coordinates of the terminal initial point to obtain the attenuated S-axis coordinates of each trajectory point after the terminal initial point.

[0169] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: determining whether the trajectory trend of the target lane change trajectory meets the target accuracy requirement; if not, obtaining the S-axis coordinate of the lane change end point in the target lane change trajectory; filtering the S-axis coordinate of the lane change end point to obtain the filtered S-axis coordinate of the lane change end point; if the filtered S-axis coordinate of the lane change end point does not meet the target accuracy requirement, continuing the filtering process until the filtered S-axis coordinate of the lane change end point meets the target accuracy requirement.

[0170] In one embodiment, when a computer program is executed by a processor, the filtering process involved in filtering the S-axis coordinate of the lane change endpoint to obtain the filtered S-axis coordinate of the lane change endpoint includes: obtaining the coordinate error between the S-axis coordinate of the lane change endpoint and the S-axis coordinate of the target position; filtering the coordinate error according to a preset filtering coefficient to obtain the filtered S-axis coordinate of the lane change endpoint.

[0171] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed 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 the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. 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). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0172] The technical features of the above embodiments may be combined arbitrarily. 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.

[0173] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for obtaining a lane-changing trajectory, It is characterized in that The method comprises: The target coordinate system is established by taking the center line of the vehicle lane as the S axis and the line perpendicular to the vehicle lane as the L axis; Acquire lane-changing coordinate information, the lane-changing coordinate information including an origin coordinate as a lane-changing starting point and an L-axis coordinate of a lane-changing end point in a lane adjacent to the lane in which the vehicle is traveling; Performing trajectory calculation based on the lane-changing coordinate information to obtain an initial lane-changing trajectory; Acquire a terminal trajectory of a preset length at the terminal of the initial lane-changing trajectory, and a terminal S-axis coordinate corresponding to the terminal trajectory; Determine the S-axis coordinate of the terminal initial point in the terminal trajectory; the terminal initial point is the decay starting point; Determine the difference between the S-axis coordinates of each track point after the terminal initial point in the terminal track and the S-axis coordinates of the terminal initial point; Performing exponential decay processing according to the difference and the S-axis coordinate of the terminal initial point to obtain the decayed S-axis coordinate of each track point after the terminal initial point; Based on a preset trajectory expression and a decaying S-axis coordinate, the L-axis coordinate of the terminal trajectory is calculated, and according to the decaying S-axis coordinate and the L-axis coordinate of the terminal trajectory, a target lane-changing trajectory is obtained; Among them, the exponential decay processing is performed according to the difference and the S-axis coordinate of the terminal initial point, and the mathematical expression of the decayed S-axis coordinate of each trajectory point after the terminal initial point is obtained as follows: Among them, S 1 Represents the S-axis coordinate of the trajectory point after decay, S 0 represents the S coordinate of the trajectory point before decay, S t Indicates the S-axis coordinate of the decay starting point, v x represents the vehicle speed, T represents the preset lane change time; The process of constructing the preset trajectory expression includes: A preset trajectory expression is constructed with the S-axis coordinate as an independent variable and the L-axis coordinate as a dependent variable, wherein the preset trajectory expression includes a plurality of first coefficients and a plurality of second coefficients.

2. The method according to claim 1, It is characterized in that The performing trajectory calculation based on the lane-changing coordinate information to obtain an initial lane-changing trajectory includes: Determining values ​​of a plurality of first coefficients according to the origin coordinates as the lane change starting point and the L-axis coordinates of the lane change end point; Calculating values ​​of a plurality of second coefficients according to the vehicle driving data, the L-axis coordinate of the lane change endpoint, and a preset lane change duration; Substituting the values ​​of the plurality of first coefficients and the values ​​of the plurality of second coefficients into the preset trajectory expression, an initial lane-changing trajectory is obtained.

3. The method according to claim 1, It is characterized in that The method further comprises: Determining whether the trajectory trend of the target lane change trajectory meets the target accuracy requirement; If not satisfied, obtaining the S-axis coordinate of the lane-changing end point in the target lane-changing trajectory; Performing filtering processing on the S-axis coordinate of the lane-changing end point to obtain the filtered S-axis coordinate of the lane-changing end point; If the filtered S-axis coordinate of the lane change endpoint does not meet the target accuracy requirement, the filtering process is continued until the filtered S-axis coordinate of the lane change endpoint meets the target accuracy requirement.

4. The method according to claim 3, It is characterized in that The filtering process on the S-axis coordinate of the lane-changing end point to obtain the filtered S-axis coordinate of the lane-changing end point includes: Obtaining a coordinate error between the S-axis coordinate of the lane change endpoint and the S-axis coordinate of the target position; The coordinate error is filtered according to a preset filter coefficient to obtain a filtered S-axis coordinate of the lane change endpoint.

5. A lane-changing trajectory acquisition device, It is characterized in that The device comprises: A coordinate system establishment module, used to establish a target coordinate system with the center line of the vehicle driving lane as the S axis and a line perpendicular to the vehicle driving lane as the L axis; A coordinate acquisition module, used to acquire lane change coordinate information, wherein the lane change coordinate information includes an origin coordinate as a lane change starting point and an L-axis coordinate of a lane change end point in a lane adjacent to the vehicle driving lane; A trajectory calculation module, used to perform trajectory calculation based on the lane-changing coordinate information to obtain an initial lane-changing trajectory; An end acquisition module, used to acquire an end trajectory of a preset length at the end of the initial lane-changing trajectory, and an end S-axis coordinate corresponding to the end trajectory; A trajectory updating module is used to determine the S-axis coordinate of the terminal initial point in the terminal trajectory; the terminal initial point is the decay starting point; determine the S-axis coordinates of each trajectory point after the terminal initial point in the terminal trajectory, and the difference between the S-axis coordinates of the terminal initial point and the S-axis coordinates of the terminal initial point; perform exponential decay processing according to the difference and the S-axis coordinate of the terminal initial point to obtain the decayed S-axis coordinates of each trajectory point after the terminal initial point; calculate the L-axis coordinate of the terminal trajectory based on a preset trajectory expression and the decayed S-axis coordinate, and obtain the target lane change trajectory according to the decayed S-axis coordinate and the L-axis coordinate of the terminal trajectory; Among them, the exponential decay processing is performed according to the difference and the S-axis coordinate of the terminal initial point, and the mathematical expression of the decayed S-axis coordinate of each trajectory point after the terminal initial point is obtained as follows: Among them, S 1 Represents the S-axis coordinate of the trajectory point after decay, S 0 represents the S coordinate of the trajectory point before decay, S t Indicates the S-axis coordinate of the decay starting point, v x represents the vehicle speed, T represents the preset lane change time; The process of constructing the preset trajectory expression includes: A preset trajectory expression is constructed with the S-axis coordinate as an independent variable and the L-axis coordinate as a dependent variable, wherein the preset trajectory expression includes a plurality of first coefficients and a plurality of second coefficients.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, It is characterized in that When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

7. A computer-readable storage medium having a computer program stored thereon, It is characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

8. A computer program product comprising a computer program, It is characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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