Vehicle lane-changing path planning method and electronic device

Abstract

The application relates to the technical field of intelligent auxiliary driving, and provides a vehicle lane-changing path planning method and electronic equipment, which are based on uniform lane changing, consider the lateral motion state of a lane-changing starting position when performing lane-changing path planning, set a first motion strategy of a vehicle in lateral acceleration during lane changing according to vehicle driving information, and confirm a speed-up and speed-down strategy of the vehicle in lateral displacement; based on different lane-changing strategies, lateral speed curves are further planned according to driving environment information, the speed change of the vehicle in lateral displacement is obtained, and then the longitudinal speed curve in longitudinal displacement is indirectly obtained; the lane-changing trajectory can be obtained by analyzing the lateral speed curve and the longitudinal speed curve at each moment. In this way, by limiting the amplitude and the change rate of the lateral acceleration, the path smoothness is improved, sudden lateral motion of the vehicle is avoided, the discomfort of passengers is reduced, and the driving safety is improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent assisted driving technology, and in particular to a vehicle lane change path planning method and electronic device. Background Technology

[0002] Intelligent vehicles can significantly improve the human travel experience and efficiency. Employing technologies such as sensors, computer vision, and artificial intelligence, intelligent vehicles can achieve safer and more precise driving and navigation, better adapting to changes in road conditions and traffic pressures, thereby greatly improving travel efficiency and providing a more comfortable travel experience. Lane changing is a crucial scenario widely used in autonomous driving, primarily aimed at enabling vehicles to navigate autonomously, avoid obstacles, or travel in lanes with better road conditions. The main challenges of lane changing in practical applications are as follows: Dynamic decision-making: It is necessary to judge the timing of lane changes in real time (such as gap selection and prediction of surrounding vehicle behavior). Existing polynomial interpolation, spline interpolation and optimization methods are based on static environment design and are difficult to efficiently handle real-time changing factors such as traffic flow and dynamic obstacles.

[0003] Multi-objective optimization includes balancing safety (collision avoidance), comfort (deceleration and steering smoothness), and efficiency (quick lane changes). Polynomial interpolation is computationally simple but produces poor smoothness; spline interpolation can generate more natural curves but has higher computational complexity; optimization methods require a trade-off between computational complexity and path smoothness.

[0004] In autonomous driving systems, static speed planning is responsible for planning the speed at each discrete point on the vehicle's driving path. When encountering obstacles during driving, the speed reliability of static speed planning is poor. Therefore, it is necessary to plan the speed in real time based on the perceived distance to the obstacle to achieve a balance between obstacle avoidance (safety) and smoothness (comfort). Summary of the Invention

[0005] This invention provides a vehicle lane change path planning method and electronic device, which solves the technical problems of existing vehicle lane change path planning schemes having large computational load and low path smoothness, resulting in low real-time performance, bumpy driving, and poor lane change efficiency.

[0006] To solve the above technical problems, the present invention provides a vehicle lane change path planning method, comprising the following steps: When a lane change command is received, vehicle driving information and driving environment information are obtained. Considering the lateral motion state at the starting position of the lane change, a first motion strategy for the vehicle in terms of lateral acceleration is set according to the vehicle driving information. Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, a lateral velocity curve is planned in terms of lateral velocity. Based on the lateral velocity curve, a longitudinal velocity curve is planned in the longitudinal velocity direction; Plan the lane change trajectory based on the lateral velocity curve and the longitudinal velocity curve.

[0007] This basic scheme is based on uniform-speed lane changing. When planning the lane change path, it considers the lateral motion state at the starting position of the lane change and sets the vehicle's first motion strategy in terms of lateral acceleration during the lane change based on the vehicle's driving information, thus confirming the vehicle's acceleration and deceleration strategies in terms of lateral displacement. Based on different lane change strategies, it further plans the lateral velocity curve according to the driving environment information to obtain the vehicle's velocity change in lateral displacement. This indirectly yields the longitudinal velocity curve in terms of longitudinal displacement. By analyzing the lateral and longitudinal velocity curves at each moment, the lane change trajectory can be obtained. In this way, by limiting the amplitude and rate of change of lateral acceleration, the smoothness of the path is improved, sudden lateral movement of the vehicle can be avoided, passenger discomfort can be reduced, and driving safety can be improved. At the same time, considering lateral acceleration constraints during planning ensures that the trajectory can be actually executed by the vehicle, satisfying kinematic and dynamic constraints, and further reducing the amount of computation to accelerate the online planning speed.

[0008] In a further implementation plan, when a lane change command is received, vehicle driving information and driving environment information are obtained, specifically: When a lane change command is received, driving environment information is obtained, and it is determined whether the lane change conditions are met based on the driving environment information. If so, vehicle driving information is further obtained; otherwise, the lane change command is detected again. The driving environment information includes obstacle information and road information.

[0009] This solution identifies the road environment based on obstacle and road information to determine whether lane-changing conditions are met, thereby ensuring lane-changing and obstacle avoidance safety.

[0010] In a further implementation scheme, considering the lateral movement state at the starting position of the lane change, a first motion strategy for the vehicle in terms of lateral acceleration during the lane change process is set based on the vehicle driving information, including: Based on steering dynamics, the centripetal force experienced by the vehicle during steering is considered, and a maximum threshold for lateral acceleration is set. Considering that the lateral motion state of the vehicle at the starting position of lane change is all in a state of no motion, the lateral velocity is determined in combination with the maximum threshold, including the first acceleration during the acceleration phase and the second acceleration during the deceleration phase.

[0011] This solution takes into account the centripetal force experienced by the vehicle during steering based on steering dynamics, and sets a maximum threshold for lateral acceleration. Since lateral acceleration is directly related to the lateral friction force (centripetal force) between the tire and the road surface, it can effectively prevent tire slippage during lane changes and ensure vehicle driving stability; at the same time, it avoids excessive thrust, which may cause dizziness or discomfort to passengers, and improves the riding experience of passengers.

[0012] In a further implementation, based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, a lateral velocity curve is planned in terms of lateral velocity, including: According to the first motion strategy planning, the lateral velocity is determined to include a first acceleration during the acceleration phase and a second acceleration during the deceleration phase; Obtain the lane width from the driving environment information; When the lane-changing strategy is to continuously accelerate in the lateral displacement direction and then directly switch to slow deceleration, the first kinematic relationship of the vehicle in the acceleration phase and the second kinematic relationship in the deceleration phase are obtained based on the first acceleration, the second acceleration and the lane width, respectively. Based on the first kinematic relationship and the second kinematic relationship, the predicted maximum velocity of the lateral velocity is solved, and the lateral velocity curve is planned in combination with the first acceleration and the second acceleration.

[0013] In a further embodiment, the first kinematic relationship is expressed as follows:

[0014] The second kinematic relationship is expressed as follows:

[0015] The relationship for lateral velocity curve planning is as follows:

[0016] In the formula, w represents the lane width. , These represent the acceleration distance during the acceleration phase and the deceleration distance during the deceleration phase, respectively. , These represent the first acceleration and the second acceleration, respectively. Represents the predicted maximum speed. Represents time, Represents lateral speed.

[0017] This solution considers the differences in lane width in different areas, the performance of different vehicles, and the perceptual abilities of different users, and sets different lane-changing strategies to meet diverse lane-changing needs. For example, when the lane-changing strategy is to continuously accelerate in the lateral displacement direction and then directly switch to slow deceleration, the lateral acceleration change is smoother and more in line with the human body's expectation of natural movement, resulting in a more comfortable riding experience. Using the lane width as a known condition, combined with the first kinematic relationship of the vehicle during the acceleration phase and the second kinematic relationship during the deceleration phase, the lateral velocity curve can be planned. This method has low computational load and high computational speed, thereby improving the real-time performance of lane-changing path planning and meeting the high real-time requirements of lane-changing scenarios.

[0018] In a further implementation, based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, a lateral velocity curve is planned in terms of lateral velocity, including: According to the first motion strategy planning, the lateral velocity is determined to include a first acceleration during the acceleration phase and a second acceleration during the deceleration phase; The lane width is obtained from the driving environment information, and the maximum expected speed for the lateral speed is set. When the lane-changing strategy is to continuously accelerate in the lateral displacement direction, then switch to uniform motion, and then slowly decelerate, the third and fourth kinematic relationships of the vehicle in the acceleration phase and the deceleration phase are obtained according to the first acceleration, the second acceleration, the maximum expected speed and the lane width, respectively. Then, the fifth kinematic relationship of the vehicle in the uniform motion phase is calculated according to the third and fourth kinematic relationships. Lateral velocity curve planning is performed based on the third, fourth, and fifth kinematic relationships and the maximum expected velocity.

[0019] In a further implementation, the third kinematic relationship is expressed as follows:

[0020] The fourth kinematic relationship is expressed as follows:

[0021] The fifth kinematic relationship is expressed as follows:

[0022] The relationship for lateral velocity curve planning is as follows:

[0023] In the formula, w represents the lane width. , , These represent the acceleration distance during the acceleration phase, the deceleration distance during the deceleration phase, and the constant speed distance during the constant speed phase, respectively. , These represent the first acceleration and the second acceleration, respectively. Represents the maximum expected speed. Represents time, Represents lateral speed.

[0024] This solution considers the differences in lane width in different areas, the performance of different vehicles, and the varying perception capabilities of different users, and sets different lane-changing strategies to meet diverse lane-changing needs. For example, when the lane-changing strategy involves continuous acceleration in the lateral displacement direction, followed by uniform motion and then slow deceleration, the third and fourth kinematic relationships of the vehicle during the acceleration and deceleration phases are obtained. Based on the third and fourth kinematic relationships, the fifth kinematic relationship of the vehicle during the uniform motion phase is calculated. Because of the known maximum expected speed and lane width, the displacement calculation is simplified in the uniform motion phase, further improving computational efficiency and enabling the system to achieve higher real-time performance.

[0025] In a further implementation, a longitudinal velocity curve is planned based on the lateral velocity curve, specifically as follows: The current vehicle speed is obtained from the vehicle driving information. Based on the vehicle changing lanes at a constant speed, the longitudinal speed curve of the vehicle is calculated according to the lateral speed curve planning and the current vehicle speed.

[0026] This scheme takes into account the safety of lane changing, and sets up a system based on vehicles changing lanes at a constant speed. The longitudinal speed is dynamically adjusted according to the lateral speed curve. The controllable motion reduces the error transmission between planning and control, thereby reducing trajectory tracking error and improving lane changing accuracy.

[0027] In a further implementation, planning the lane change trajectory based on the lateral velocity curve and the longitudinal velocity curve includes: Calculate the abscissa information of each trajectory point based on the lateral velocity curve; Calculate the ordinate information of each trajectory point based on the longitudinal velocity curve; Obtain the x-coordinate and y-coordinate information of all trajectory points to plan the lane change trajectory.

[0028] This scheme generates trajectory points directly by simultaneously integrating the lateral and longitudinal velocities, ensuring that the vehicle's motion direction is strictly consistent with its velocity direction. This avoids the dynamic inconsistency problem caused by "path-velocity decoupling" in traditional geometric planning. Furthermore, the independent calculation of the lateral and longitudinal coordinate information is simpler and more efficient, and the step-by-step calculation has high real-time performance.

[0029] The present invention also provides an electronic device, including a memory and a processor, wherein the processor is configured to execute program instructions stored in the memory to implement the vehicle lane change path planning method described above. Attached Figure Description

[0030] Figure 1 This is a flowchart of a vehicle lane change path planning method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the reference coordinate system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of obstacle detection provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the lane environment provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of a speed curve planning provided by an embodiment of the present invention; Figure 6 This is another schematic diagram of speed curve planning provided by an embodiment of the present invention; Figure 7 This is a schematic diagram of vehicle speed division provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of a vehicle lane-changing trajectory provided in an embodiment of the present invention. Detailed Implementation

[0031] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. The embodiments are given for illustrative purposes only and should not be construed as limiting the present invention. The accompanying drawings are for reference and illustration only and do not constitute a limitation on the scope of patent protection of the present invention, because many changes can be made to the present invention without departing from the spirit and scope of the present invention.

[0032] Example 1 This invention provides a vehicle lane change path planning method, such as... Figures 1-8 As shown, in this embodiment, the steps include: S0. Perform lane change intention detection. When a lane change intention is detected, generate a lane change command, including: See Figure 2 A reference coordinate system (e.g., latitude and longitude coordinates) is established based on the vehicle's driving environment, and the vehicle's pose is obtained through the vehicle positioning system and the global positioning system. The position is represented by the coordinates of the midpoint of the rear axle of the vehicle body. The angle between the vehicle's heading and the x-axis represents the yaw angle. .

[0033] The vehicle's driving environment is assessed using a sensing system to detect and locate obstacles. (See also...) Figure 3For example, the coordinates of a perceived obstacle (including pedestrians, vehicles, water-filled barriers, etc.) are ,in .

[0034] The system obtains the intention to actively change lanes based on vehicle operation; or, it determines whether the conditions for automatic lane changing are met based on obstacle location and vehicle driving status, and if so, generates an automatic lane changing intention. A lane change instruction is generated based on the stated intention to change lanes actively or automatically.

[0035] In actual driving, lane changing generally includes driver-initiated lane changes, such as activating the turn signal or, when conditions permit, using a lane change lever. There is also automatic lane changing, where the vehicle's perception system detects poor driving conditions in the current lane and a better driving condition in the adjacent lane, thus autonomously changing lanes.

[0036] S1. Upon receiving a lane change command, obtain vehicle driving information and driving environment information, specifically: When a lane change command is received, driving environment information is obtained, and it is determined whether the lane change conditions are met based on the driving environment information. If so, vehicle driving information is further obtained; otherwise, the lane change command is detected again. The driving environment information includes obstacle information and road information, with road information including lane width; vehicle driving information includes current vehicle speed.

[0037] If the vehicle is in autonomous driving mode, when the lane change requirement is met and the lane change conditions permit, the autonomous driving system plans all possible paths and guides the vehicle to change lanes.

[0038] In this embodiment, see Figure 4 The lane-changing conditions include the existence of lanes that can be changed (each lane has a width of w, i.e., the lateral displacement required to perform a lane-changing action is w), and the longitudinal safety distance for the vehicle to change lanes is s, i.e., the distance to the obstacle in front.

[0039] This embodiment identifies the road environment based on obstacle information and road information to determine whether lane-changing conditions are met, thereby ensuring lane-changing and obstacle avoidance safety.

[0040] S2. Considering the lateral motion state at the starting position of the lane change, set the first motion strategy of the vehicle in terms of lateral acceleration during the lane change process based on the vehicle driving information, including: Based on steering dynamics, the centripetal force experienced by the vehicle during steering is considered, and a maximum threshold for lateral acceleration is set. Considering that the lateral motion state of the vehicle at the starting position of lane change is all in a state of no motion, the lateral velocity is determined in combination with the maximum threshold, including the first acceleration during the acceleration phase and the second acceleration during the deceleration phase.

[0041] According to Ackermann steering kinematics, the turning radius R of a vehicle is related to the steering wheel angle:

[0042] in This refers to the vehicle's wheelbase. Let be the steering wheel angle of the vehicle, and k be the steering ratio between the steering wheel angle and the front wheel angle.

[0043] Lateral acceleration refers to acceleration perpendicular to the direction of vehicle travel. It mainly occurs when a vehicle is turning and manifests as a tendency for the vehicle to be "thrown" off its path. The formula for calculating the magnitude of lateral acceleration is:

[0044] Where v represents the actual speed of the vehicle and R represents the turning radius of the vehicle.

[0045] This means that the faster the vehicle speed and the larger the steering wheel angle, the greater the lateral acceleration. As speed increases, the centripetal force required for turning also increases, leading to greater lateral acceleration. This can cause passengers to feel a stronger thrust, potentially causing discomfort or even danger. At the same speed, a larger steering wheel angle requires more centripetal force, resulting in greater lateral acceleration. In practical driving, this manifests as a greater likelihood of skidding or rollover when the vehicle is cornering sharply. Let's assume the maximum lateral acceleration that the vehicle and its occupants can withstand is... Considering the different sensations of acceleration and deceleration, the acceleration during the lateral velocity acceleration and deceleration phases of lane changes are set as the first acceleration, respectively. Second acceleration .

[0046] Furthermore, assuming that the vehicle's lateral velocity starts from 0 when performing a lane change and also decreases to 0 at the end of the lane change, the maximum expected lateral velocity is... .

[0047] This embodiment takes into account the centripetal force experienced by the vehicle during steering based on steering dynamics, and sets a maximum threshold for lateral acceleration. Since lateral acceleration is directly related to the lateral friction force (centripetal force) between the tire and the road surface, it can effectively prevent tire slippage during lane changes and ensure vehicle driving stability; at the same time, it avoids excessive thrust, which may cause dizziness or discomfort to passengers and improve the riding experience of passengers.

[0048] S3. Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, plan the lateral velocity curve in the lateral velocity. In this embodiment, the speed is planned as follows: the lateral speed at the starting point is 0 and the lateral speed at the ending point is 0. This can be divided into two cases, namely, cases A and B below.

[0049] The first type, see below. Figure 5 Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, the lateral velocity curve is planned in terms of lateral velocity, including: S31A. According to the first motion strategy planning, the lateral velocity is determined to include a first acceleration during the acceleration phase and a second acceleration during the deceleration phase. S32A. Obtain the lane width from the driving environment information; S33A. When the lane-changing strategy is to continuously accelerate in the lateral displacement direction and then directly switch to slow deceleration, the first kinematic relationship of the vehicle in the acceleration phase and the second kinematic relationship in the deceleration phase are obtained according to the first acceleration, the second acceleration and the lane width, respectively. S34A. Based on the first kinematic relationship and the second kinematic relationship, the predicted maximum speed of the lateral velocity is solved, and the lateral velocity curve is planned in combination with the first acceleration and the second acceleration.

[0050] In this embodiment, when the lane-changing strategy involves continuous acceleration in the lateral displacement direction followed by slow deceleration, The planned velocity curve is shown in the figure, where the horizontal axis represents time and the vertical axis represents lateral velocity.

[0051] The distance traveled during the acceleration phase is shown in the first kinematic relationship below:

[0052] The travel distance during the deceleration phase is shown in the second kinematic relationship below:

[0053] Since the lateral movement distance is w, then:

[0054] The predicted maximum speed during the lane change process can be obtained. :

[0055] Therefore, the relationship for the lateral velocity curve planning is as follows:

[0056] In the formula, w represents the lane width. , These represent the acceleration distance during the acceleration phase and the deceleration distance during the deceleration phase, respectively. , These represent the first acceleration and the second acceleration, respectively. Represents the predicted maximum speed. Represents time, Represents lateral speed.

[0057] This embodiment takes into account the differences in lane width in different areas, the performance of different vehicles, and the different perception abilities of different users, and sets different lane-changing strategies to meet diverse lane-changing needs. For example, when the lane-changing strategy is to continuously accelerate in the lateral displacement direction and then directly switch to slow deceleration, the lateral acceleration change is smoother and more in line with the human body's expectation of natural movement, resulting in a more comfortable riding experience. Using the lane width as a known condition, the lateral velocity curve can be planned by combining the first kinematic relationship of the vehicle during the acceleration phase and the second kinematic relationship during the deceleration phase. The computation is small and the calculation rate is high, which can improve the real-time performance of lane-changing path planning and meet the high real-time requirements of lane-changing scenarios.

[0058] The second type, see below. Figure 6 Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, the lateral velocity curve is planned in terms of lateral velocity, including: S31B. According to the first motion strategy planning, the lateral velocity is determined to include a first acceleration during the acceleration phase and a second acceleration during the deceleration phase. S32B: Obtain the lane width from the driving environment information and set the maximum expected speed for the lateral speed; S33B. When the lane-changing strategy is to continuously accelerate in the lateral displacement direction, then switch to uniform motion, and then slowly decelerate, the third kinematic relationship and the fourth kinematic relationship of the vehicle in the acceleration phase and the deceleration phase are obtained according to the first acceleration, the second acceleration, the maximum expected speed and the lane width, respectively. Then, the fifth kinematic relationship of the vehicle in the uniform motion phase is calculated according to the third kinematic relationship and the fourth kinematic relationship. S34B. Based on the third kinematic relationship, the fourth kinematic relationship, the fifth kinematic relationship, and the maximum expected velocity, perform lateral velocity curve planning.

[0059] In this embodiment, when the lane-changing strategy involves continuous acceleration in the lateral displacement direction, followed by constant speed motion, and then slow deceleration, The planned velocity curve is shown in the figure, where the horizontal axis represents time and the vertical axis represents lateral velocity.

[0060] The travel distance during the acceleration phase is shown in the third kinematic relationship below:

[0061] The travel distance during the deceleration phase is shown in the fourth kinematic relationship below:

[0062] Since the lateral movement distance is w, then:

[0063] The distance traveled at the maximum desired speed during the uniform motion phase is shown in the fifth kinematic relationship below:

[0064] Therefore, the relationship for the lateral velocity curve planning is as follows:

[0065] In the formula, w represents the lane width. , , These represent the acceleration distance during the acceleration phase, the deceleration distance during the deceleration phase, and the constant speed distance during the constant speed phase, respectively. , These represent the first acceleration and the second acceleration, respectively. Represents the maximum expected speed. Represents time, Represents lateral speed.

[0066] This embodiment takes into account the differences in lane width in different areas, the performance of different vehicles, and the perception capabilities of different users, and sets different lane-changing strategies to meet diverse lane-changing needs. For example, when the lane-changing strategy is to continuously accelerate in the lateral displacement direction, then transition to uniform speed, and then slowly decelerate, the third and fourth kinematic relationships of the vehicle during the acceleration and deceleration phases are obtained. Based on the third and fourth kinematic relationships, the fifth kinematic relationship of the vehicle during the uniform speed phase is calculated. Based on the known maximum expected speed and lane width, the displacement calculation is simplified in the uniform speed segment, further improving the calculation efficiency and enabling the system to have higher real-time performance.

[0067] S4. Based on the aforementioned transverse velocity curve, plan the longitudinal velocity curve in the longitudinal direction, specifically as follows: The current vehicle speed is obtained from the vehicle driving information. Based on the vehicle changing lanes at a constant speed, the longitudinal speed curve of the vehicle is calculated according to the lateral speed curve planning and the current vehicle speed.

[0068] For details, see Figure 7 Assuming the vehicle's overall speed v remains constant during the lane change process, since the vehicle speed can be decomposed into lateral speed... and longitudinal speed As shown in the figure below, due to the lateral speed Given the current vehicle speed V, then the longitudinal vehicle speed... (And it is also a function of time) is:

[0069] This embodiment takes into account the safety of lane changing, and sets up a system based on uniform vehicle lane changing. The longitudinal speed is dynamically adjusted according to the lateral speed curve. The controllable motion reduces the error transmission between planning and control, thereby reducing trajectory tracking error and improving lane changing accuracy.

[0070] S5. Plan the lane-changing trajectory based on the lateral velocity curve and the longitudinal velocity curve, including: Calculate the abscissa information of each trajectory point based on the lateral velocity curve; Calculate the ordinate information of each trajectory point based on the longitudinal velocity curve; Obtain the x-coordinate and y-coordinate information of all trajectory points to plan the lane change trajectory.

[0071] For details, see Figure 8 In steps S3 and S4, the lateral and longitudinal velocities of the vehicle during the lane change process are planned as functions of time. The vehicle's trajectory points are then the integrals of these velocities with respect to time. That is, the horizontal axis represents the integral of the lateral velocity with respect to time, denoted as... The vertical axis represents the integral of the longitudinal velocity with respect to time, denoted as... This allows us to find a time-dependent path. Then the path points... , where t is time, which is a set of time-related points, thus planning the lane change trajectory.

[0072]

[0073] This embodiment generates trajectory points directly by synchronously integrating the lateral and longitudinal velocities, ensuring that the vehicle's motion direction is strictly consistent with the velocity direction. This avoids the dynamic inconsistency problem caused by "path-velocity decoupling" in traditional geometric planning. Furthermore, the independent calculation of the lateral and longitudinal coordinate information is simpler and more efficient, and the step-by-step calculation has high real-time performance.

[0074] Example 2 This invention also provides an electronic device, including a memory and a processor, wherein the processor is used to execute program instructions stored in the memory to implement the vehicle lane change path planning method as described in Embodiment 1 above. This invention, based on uniform-speed lane changing, considers the lateral motion state at the starting position of the lane change during path planning. It sets a first motion strategy for the vehicle's lateral acceleration during the lane change based on vehicle driving information, and confirms the vehicle's acceleration and deceleration strategies for lateral displacement. Based on different lane changing strategies, it further plans lateral velocity curves according to driving environment information to obtain the vehicle's velocity changes in lateral displacement. This indirectly yields the longitudinal velocity curve in longitudinal displacement. By analyzing the lateral and longitudinal velocity curves at each moment, the lane change trajectory can be obtained. Thus, by limiting the amplitude and rate of change of lateral acceleration, the path smoothness is improved, sudden lateral movement of the vehicle can be avoided, passenger discomfort can be reduced, and driving safety can be improved. Simultaneously, considering lateral acceleration constraints during planning ensures that the trajectory can be actually executed by the vehicle, satisfying kinematic and dynamic constraints, and further reducing computational load to accelerate online planning speed.

[0075] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A vehicle lane-change path planning method, characterized in that, Including the following steps: When a lane change command is received, vehicle driving information and driving environment information are obtained. Considering the lateral motion state at the starting position of the lane change, a first motion strategy for the vehicle in terms of lateral acceleration is set according to the vehicle driving information. Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, a lateral velocity curve is planned in terms of lateral velocity. Based on the lateral velocity curve, a longitudinal velocity curve is planned in the longitudinal velocity direction; Plan the lane change trajectory based on the lateral velocity curve and the longitudinal velocity curve; Specifically, considering the lateral movement state at the starting position of the lane change, a first motion strategy for the vehicle in terms of lateral acceleration is set based on the vehicle driving information, including: Based on the steering dynamics, the centripetal force experienced by the vehicle during steering is considered, and a maximum threshold for lateral acceleration is set. Considering that the lateral motion state of the vehicle at the starting position of lane change is all in a state of no motion, the lateral velocity is determined in combination with the maximum threshold, including the first acceleration during the acceleration phase and the second acceleration during the deceleration phase. The lane-changing strategy is to continuously accelerate in the lateral displacement direction and then directly switch to slow deceleration, or to continuously accelerate in the lateral displacement direction, then switch to uniform motion and then switch to slow deceleration.

2. The vehicle lane-changing path planning method as described in claim 1, characterized in that, When a lane change command is received, vehicle driving information and driving environment information are obtained, specifically: When a lane change command is received, driving environment information is obtained, and it is determined whether the lane change conditions are met based on the driving environment information. If so, vehicle driving information is further obtained; otherwise, the lane change command is detected again. The driving environment information includes obstacle information and road information.

3. The vehicle lane-changing path planning method as described in claim 1, characterized in that, Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, a lateral velocity curve is planned in terms of lateral velocity, including: According to the first motion strategy planning, the lateral velocity is determined to include a first acceleration during the acceleration phase and a second acceleration during the deceleration phase; Obtain the lane width from the driving environment information; When the lane-changing strategy is to continuously accelerate in the lateral displacement direction and then directly switch to slow deceleration, the first kinematic relationship of the vehicle in the acceleration phase and the second kinematic relationship in the deceleration phase are obtained according to the first acceleration, the second acceleration and the lane width, respectively. Based on the first kinematic relationship and the second kinematic relationship, the predicted maximum speed of the lateral velocity is solved, and the lateral velocity curve is planned in combination with the first acceleration and the second acceleration.

4. The vehicle lane-changing path planning method as described in claim 3, characterized in that: The first kinematic relationship is expressed as follows: The second kinematic relationship is expressed as follows: The relationship for lateral velocity curve planning is as follows: In the formula, w represents the lane width. , These represent the acceleration distance during the acceleration phase and the deceleration distance during the deceleration phase, respectively. , These represent the first acceleration and the second acceleration, respectively. Represents the predicted maximum speed. Represents time, Represents lateral speed.

5. The vehicle lane-changing path planning method as described in claim 1, characterized in that, Based on different lane-changing strategies, and combining the driving environment information and the first motion strategy, a lateral velocity curve is planned in terms of lateral velocity, including: According to the first motion strategy planning, the lateral velocity is determined to include a first acceleration during the acceleration phase and a second acceleration during the deceleration phase; The lane width is obtained from the driving environment information, and the maximum expected speed for the lateral speed is set. When the lane-changing strategy is to continuously accelerate in the lateral displacement direction, then switch to uniform motion, and then slowly decelerate, the third and fourth kinematic relationships of the vehicle in the acceleration phase and the deceleration phase are obtained according to the first acceleration, the second acceleration, the maximum expected speed and the lane width, respectively. Then, the fifth kinematic relationship of the vehicle in the uniform motion phase is calculated according to the third and fourth kinematic relationships. Lateral velocity curve planning is performed based on the third, fourth, and fifth kinematic relationships and the maximum expected velocity.

6. The vehicle lane change path planning method as described in claim 5, characterized in that: The third kinematic relationship is expressed as follows: The fourth kinematic relationship is expressed as follows: The fifth kinematic relationship is expressed as follows: The relationship for lateral velocity curve planning is as follows: In the formula, w represents the lane width. , , These represent the acceleration distance during the acceleration phase, the deceleration distance during the deceleration phase, and the constant speed distance during the constant speed phase, respectively. , These represent the first acceleration and the second acceleration, respectively. Represents the maximum expected speed. Represents time, Represents lateral speed.

7. The vehicle lane-changing path planning method as described in claim 1, characterized in that, Based on the aforementioned lateral velocity curve, the longitudinal velocity curve is planned as follows: The current vehicle speed is obtained from the vehicle driving information. Based on the vehicle changing lanes at a constant speed, the longitudinal speed curve of the vehicle is calculated according to the lateral speed curve planning and the current vehicle speed.

8. The vehicle lane-changing path planning method as described in claim 1, characterized in that, Planning a lane-changing trajectory based on the lateral velocity curve and the longitudinal velocity curve includes: Calculate the x-coordinate information of each trajectory point based on the lateral velocity curve; Calculate the ordinate information of each trajectory point based on the longitudinal velocity curve; Obtain the x-coordinate and y-coordinate information of all trajectory points to plan the lane change trajectory.

9. An electronic device, characterized in that, It includes a memory and a processor, the processor being configured to execute program instructions stored in the memory to implement the vehicle lane change path planning method as described in any one of claims 1 to 8.

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