Trajectory planning method and device, computer equipment and computer readable storage medium

Abstract

The application provides a trajectory planning method. The method comprises: generating a basic trajectory according to a dynamically set curvature-related parameter; diffusing a plurality of starting point basic trajectories along a plurality of preset directions with the starting point as the center; diffusing a plurality of target point basic trajectories along a plurality of preset directions with the target point as the center; combining the basic trajectories of the starting point and the target point to form a plurality of trajectory combinations; for each trajectory combination, fitting the end point of the starting point basic trajectory as a starting circle to obtain a circle center and a radius, fitting the end point of the target point basic trajectory as a target circle to obtain a circle center and a radius, determining a tangent corresponding to the two circles according to the relationship between the distance between the two circle centers and the sum of the two circle radii, screening out the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point, and connecting the screened tangent with the corresponding starting point basic sub-trajectory and target point basic sub-trajectory to form an overall planning trajectory. The method improves the control accuracy and motion stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of trajectory planning. Specifically, the present application relates to a trajectory planning method, device, computer equipment and computer readable storage medium. BACKGROUND

[0002] When an unmanned mobile platform (such as an unmanned wheeled robot, an unmanned vehicle, etc.) works, it needs to execute a task from a starting point to a target point, and the process relies on a trajectory generated by global path planning to guide the moving route of the mobile platform.

[0003] Traditional trajectory planning methods usually use Dubins curves or Reeds-Shepp curves to generate basic trajectories. However, the trajectories generated by these two curves have the problem of sudden change of curvature. Without post-trajectory smoothing optimization, such trajectories with sudden change of curvature will cause unstable control in high-speed motion scenarios, affecting the task execution efficiency and platform safety. SUMMARY

[0004] Therefore, it is necessary to provide a trajectory planning method, device, computer equipment and computer readable storage medium to solve the above technical problems.

[0005] In a first aspect, the present application provides a trajectory planning method. The method comprises:

[0006] generating a basic trajectory based on a dynamically set curvature-related parameter; wherein the curvature-related parameter includes a maximum curvature and a curvature change rate; the basic trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature, connected in turn, the curvature of the first spiral trajectory gradually increases from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreases from the maximum curvature to the initial value at the curvature change rate;

[0007] spreading to generate a plurality of starting point basic trajectories along a plurality of preset directions with the starting point as the center; spreading to generate a plurality of target point basic trajectories along a plurality of preset directions with the target point as the center; combining each basic trajectory of the starting point and the target point to form a plurality of trajectory combinations;

[0008] For the starting point base trajectory and the target point base trajectory in each trajectory combination, the end point of the starting point base trajectory is fitted as a starting circle, the center and the radius are obtained, the end point of the target point base trajectory is fitted as a target circle, the center and the radius are obtained, the tangent corresponding to the two circles is determined according to the relationship between the distance of the two centers and the sum of the two radii, the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point is screened out, the sub-trajectory of the starting point base trajectory from the starting point to the tangent point of the screened tangent on the starting circle is intercepted, the sub-trajectory of the target point base trajectory from the tangent point of the screened tangent on the target circle to the target point is intercepted, the screened tangent is connected with the corresponding intercepted starting point base sub-trajectory and target point base sub-trajectory, and the overall planning trajectory is formed.

[0009] In one of the embodiments, the base trajectory is generated according to the dynamically set curvature-related parameters, including:

[0010] Starting from the initial value of the curvature, the trajectory points are discretely sampled at a fixed interval, the circular arc is constructed between adjacent points according to the current curvature, the curvature is increased according to the curvature change rate, until the curvature reaches the maximum curvature, and the first spiral trajectory is obtained.

[0011] In one of the embodiments, the base trajectory is generated according to the dynamically set curvature-related parameters, and further including:

[0012] After the curvature reaches the maximum curvature, the maximum curvature is kept unchanged, the trajectory points are sampled according to the preset number, and the circular arc trajectory is obtained.

[0013] In one of the embodiments, the base trajectory is generated according to the dynamically set curvature-related parameters, and further including:

[0014] After the circular arc trajectory is generated, the trajectory points are discretely sampled at a fixed interval starting from the maximum curvature, the circular arc is constructed between adjacent points according to the current curvature, the curvature is decreased according to the curvature change rate, until the curvature falls back to the initial value, and the second spiral trajectory is obtained.

[0015] In one of the embodiments, a plurality of starting point base trajectories are generated by diffusing from the starting point along a plurality of preset directions, a plurality of target point base trajectories are generated by diffusing from the target point along a plurality of preset directions, and each base trajectory of the starting point and the target point is combined to form a plurality of trajectory combinations, including:

[0016] Four starting point base trajectories are generated by diffusing from the starting point along the left front, right front, left rear and right rear directions respectively;

[0017] Four target point base trajectories are generated by diffusing from the target point along the left front, right front, left rear and right rear directions respectively;

[0018] The four starting point base tracks and the four target point base tracks are combined to form sixteen track combinations.

[0019] In one of the embodiments, the tangent line corresponding to the two circles is determined according to the relationship between the distance between the two circle centers and the sum of the two circle radii, including:

[0020] If the distance between the two circle centers is greater than the sum of the two circle radii, four tangent lines of the two circles are calculated.

[0021] If the distance between the two circle centers is less than or equal to the sum of the two circle radii, two tangent lines of the two circles are calculated.

[0022] In one of the embodiments, the method further includes:

[0023] For each overall planning track, it is checked whether it intersects with the environmental obstacles. If it intersects, the overall planning track is discarded. If it does not intersect, the overall planning track is marked as a collision-free track.

[0024] The cost function of each collision-free track is calculated by weighting. The cost function includes the number of gear shifts and the length of the track.

[0025] The collision-free track with the minimum cost function value is selected as the final executed planning track.

[0026] In a second aspect, the application provides a trajectory planning device. The device includes:

[0027] A base track generation module is configured to generate a base track according to a dynamically set curvature-related parameter. The curvature-related parameter includes a maximum curvature and a curvature change rate. The base track is composed of a first spiral track with increasing curvature, a circular arc track with fixed curvature, and a second spiral track with decreasing curvature, which are sequentially connected. The curvature of the first spiral track gradually increases from an initial value to the maximum curvature at the curvature change rate. The curvature of the circular arc track is the maximum curvature. The curvature of the second spiral track gradually decreases from the maximum curvature to the initial value at the curvature change rate.

[0028] A base track combination module is configured to generate a plurality of starting point base tracks by spreading around a starting point along a plurality of preset directions, generate a plurality of target point base tracks by spreading around a target point along a plurality of preset directions, and combine the base tracks of the starting point and the target point to form a plurality of track combinations.

[0029] The whole trajectory planning module is configured to, for the start point base trajectory and the target point base trajectory in each trajectory combination, fit the end point of the start point base trajectory as a start circle, obtain the center and radius of the start circle, fit the end point of the target point base trajectory as a target circle, obtain the center and radius of the target circle, determine the tangent corresponding to the two circles according to the relationship between the distance between the two centers and the sum of the two radii, screen the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point, intercept a sub-trajectory of the start point base trajectory from the start point to the tangent point of the screened tangent on the start circle, intercept a sub-trajectory of the target point base trajectory from the tangent point of the screened tangent on the target circle to the target point, connect the screened tangent with the corresponding intercepted start point base sub-trajectory and target point base sub-trajectory, and form a whole planning trajectory.

[0030] In a third aspect, the present application also provides a computer device. The computer device comprises a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0031] According to the dynamically set curvature-related parameters, a base trajectory is generated; wherein the curvature-related parameters include a maximum curvature and a curvature change rate; the base trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature connected in sequence, the curvature of the first spiral trajectory gradually increases from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreases from the maximum curvature to the initial value at the curvature change rate;

[0032] A plurality of start point base trajectories are generated by diffusing in a plurality of preset directions with the start point as the center; a plurality of target point base trajectories are generated by diffusing in a plurality of preset directions with the target point as the center; and each base trajectory of the start point and the target point is combined to form a plurality of trajectory combinations.

[0033] For the start point base trajectory and the target point base trajectory in each trajectory combination, the end point of the start point base trajectory is fitted as a start circle, the center and radius of the start circle are obtained, the end point of the target point base trajectory is fitted as a target circle, the center and radius of the target circle are obtained, the tangent corresponding to the two circles is determined according to the relationship between the distance between the two centers and the sum of the two radii, the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point is screened, a sub-trajectory of the start point base trajectory from the start point to the tangent point of the screened tangent on the start circle is intercepted, a sub-trajectory of the target point base trajectory from the tangent point of the screened tangent on the target circle to the target point is intercepted, the screened tangent is connected with the corresponding intercepted start point base sub-trajectory and target point base sub-trajectory, and a whole planning trajectory is formed.

[0034] In a fourth aspect, the present application also provides a computer readable storage medium. The computer readable storage medium has a computer program stored thereon, and the computer program, when executed by a processor, implements the following steps:

[0035] generating a basic trajectory according to a dynamically set curvature-related parameter, wherein the curvature-related parameter comprises a maximum curvature and a curvature change rate; the basic trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature connected in sequence, the curvature of the first spiral trajectory gradually increases from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreases from the maximum curvature to the initial value at the curvature change rate;

[0036] generating a plurality of starting point basic trajectories by diffusion along a plurality of preset directions with the starting point as the center; generating a plurality of target point basic trajectories by diffusion along a plurality of preset directions with the target point as the center; and combining the basic trajectories of the starting point and the target point to form a plurality of trajectory combinations;

[0037] for the starting point basic trajectory and the target point basic trajectory in each trajectory combination, fitting the end point of the starting point basic trajectory as a starting circle to obtain a center and a radius, fitting the end point of the target point basic trajectory as a target circle to obtain a center and a radius, determining a tangent corresponding to the two circles according to the relationship between the distance between the two centers and the sum of the two radii, screening a tangent whose direction is consistent with the heading of the corresponding circle at the tangent point, intercepting a sub-trajectory of the starting point basic trajectory from the starting point to the tangent point of the screened tangent on the starting circle, intercepting a sub-trajectory of the target point basic trajectory from the tangent point of the screened tangent on the target circle to the target point, and connecting the screened tangent and the corresponding intercepted starting point basic sub-trajectory and target point basic sub-trajectory to form an overall planning trajectory.

[0038] In a fifth aspect, the present application also provides a computer program product. The computer program product comprises a computer program, and the computer program, when executed by a processor, implements the following steps:

[0039] generating a basic trajectory according to a dynamically set curvature-related parameter, wherein the curvature-related parameter comprises a maximum curvature and a curvature change rate; the basic trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature connected in sequence, the curvature of the first spiral trajectory gradually increases from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreases from the maximum curvature to the initial value at the curvature change rate;

[0040] The starting point is taken as a center to diffuse in multiple preset directions to generate multiple starting point basis tracks, and the target point is taken as a center to diffuse in multiple preset directions to generate multiple target point basis tracks; the basis tracks of the starting point and the target point are combined to form multiple track combinations;

[0041] For the starting point basis track and the target point basis track in each track combination, the end point of the starting point basis track is fitted as a starting circle to obtain a circle center and a radius, the end point of the target point basis track is fitted as a target circle to obtain a circle center and a radius, the tangent corresponding to the two circles is determined according to the relationship between the distance between the two circle centers and the sum of the two circle radii, the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point is screened out, the sub-track of the starting point basis track from the starting point to the tangent point of the screened-out tangent on the starting circle is intercepted, the sub-track of the target point basis track from the tangent point of the screened-out tangent on the target circle to the target point is intercepted, the screened-out tangent and the corresponding intercepted starting point basis sub-track and target point basis sub-track are connected to form an overall planning track.

[0042] The above-mentioned track planning method, device, computer equipment and computer readable storage medium, by dynamically configuring the maximum curvature and the curvature change rate, construct the basis track composed of the first spiral track with increasing curvature, the circular arc track with fixed curvature and the second spiral track with decreasing curvature. The first spiral track and the second spiral track are spiral tracks with uniform curvature change rate and fixed curvature change rate, so that the curvature of the basis track gradually and uniformly increases from zero to the set maximum curvature, and then gradually and uniformly decreases from the maximum curvature to zero. Then, the basis tracks generated by the multi-direction diffusion of the starting point and the target point are fitted into circles, the tangent is determined according to the relationship between the distance between the two circle centers and the sum of the radii, and the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point is screened out for track connection. The problem of sudden change and discontinuity of curvature in traditional track planning is effectively solved, the continuous connection of the track curvature from the starting point to the target point is realized, and the control accuracy and motion stability are improved. At the same time, the maximum curvature and the curvature change rate are dynamic adjustable parameters, which can be dynamically set before planning according to different vehicles and track requirements, so as to meet the diversified requirements of curvature characteristics in different scenes and enhance the flexibility and adaptability of track planning. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 It is a flowchart of the track planning method in one embodiment;

[0044] Figure 2 It is a starting point basis track sampling schematic diagram in one embodiment;

[0045] Figure 3 It is a local sampling track effect diagram in one embodiment;

[0046] Figure 4 Fig. 1 is a schematic diagram of sampling a base trajectory of a starting point and a target point in an embodiment;

[0047] Figure 5 Fig. 2 is a schematic diagram of calculating a tangent corresponding to a circular arc of a starting point and a target point in an embodiment;

[0048] Figure 6 Fig. 3 is a schematic diagram of calculating a final overall planning trajectory in an embodiment;

[0049] Figure 7 Fig. 4 is a structural block diagram of a trajectory planning device in an embodiment;

[0050] Figure 8 Fig. 5 is an internal structural diagram of a computer device in an embodiment. DETAILED DESCRIPTION

[0051] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0052] In an embodiment, as shown in Fig. 1, a trajectory planning method is provided, which comprises the following steps S102-S106: Figure 1

[0053] Step S102, generating a base trajectory according to a dynamically set curvature-related parameter.

[0054] The curvature-related parameter includes a maximum curvature and a curvature change rate. The base trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature, the curvature of the first spiral trajectory gradually increases from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreases from the maximum curvature to the initial value at the curvature change rate.

[0055] Specifically, first, a segmented base trajectory is calculated according to a dynamically set maximum curvature and a curvature change rate . The base trajectory is composed of three parts, the first part is a first spiral trajectory from a curvature initial value zero to the maximum curvature , the second part is a circular arc trajectory with a curvature of , and the third part is a second spiral trajectory with a curvature from to zero. Since the curvature change rate ​is the value of the initialization setting, so in the calculation of the spiral trajectory, the trajectory is discretized into trajectory points at 10 cm intervals, and each two trajectory points are approximately considered as a circular arc curve with fixed curvature, and the change of the curvature is calculated according to the curvature change rate, so that the spiral trajectory is calculated step by step, as shown in Figures 2-4 The circular arc trajectory samples the lengths of the circular arc trajectories at different point numbers, from 2 points to the length of the target point number set, to calculate the circular arc trajectories at different lengths, and finally the first spiral trajectory, the circular arc trajectory and the second spiral trajectory are combined to obtain the basic trajectory.

[0056] In step S104, a plurality of starting point basic trajectories are generated by diffusing from the starting point along a plurality of preset directions, and a plurality of target point basic trajectories are generated by diffusing from the target point along a plurality of preset directions. The basic trajectories of the starting point and the target point are combined to form a plurality of trajectory combinations.

[0057] Specifically, the global planning considers both forward and backward directions, so four starting point basic trajectories are generated by diffusing from the starting point along the left front, right front, left rear and right rear directions respectively. Four target point basic trajectories are generated by diffusing from the target point along the left front, right front, left rear and right rear directions respectively. The four starting point basic trajectories and the four target point basic trajectories are combined to form sixteen trajectory combinations.

[0058] In step S106, for the starting point basic trajectory and the target point basic trajectory in each trajectory combination, the end point of the starting point basic trajectory is fitted as a starting circle to obtain the center and the radius, the end point of the target point basic trajectory is fitted as a target circle to obtain the center and the radius, according to the relationship between the distance between the two centers and the sum of the two radii, the tangent corresponding to the two circles is determined, the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point is selected, as shown in Figure 5 The sub-trajectory of the starting point basic trajectory from the starting point to the tangent point of the selected tangent on the starting circle is intercepted, the sub-trajectory of the target point basic trajectory from the tangent point of the selected tangent on the target circle to the target point is intercepted, the selected tangent and the corresponding intercepted starting point basic sub-trajectory and target point basic sub-trajectory are connected to form an overall planning trajectory, as shown in Figure 6 .

[0059] Specifically, sixteen trajectory combinations are calculated to find reasonable trajectories. After the basic trajectory is diffused, the last point of each sampled trajectory is fitted with a circle to calculate the radius and center coordinates of the circle. Therefore, the trajectory center corresponding to the current starting point and target point needs to be calculated, and then the corresponding circular arc tangent is calculated according to the distance relationship of the center. If the distance between the centers is greater than 2 times the radius, the two circles correspond to four tangents. If the distance between the centers is less than or equal to 2 times the radius, the two circles correspond to two tangents. Then it is calculated whether the heading direction of the tangent is consistent with the heading direction of the circular arc. If it is consistent, the trajectory calculation is complete, and the tangent point of the tangent at the starting point and the target point corresponding to the trajectory arc is found. The starting point and the target point of the basic sub-trajectory under the tangent point are obtained. The overall planning trajectory is the starting point basic sub-trajectory, the straight line tangent trajectory and the target point basic sub-trajectory.

[0060] The above trajectory planning method configures the maximum curvature and the curvature change rate dynamically, constructs a basic trajectory composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature. The first spiral trajectory and the second spiral trajectory are spiral trajectories with uniform curvature change at a fixed curvature change rate, so that the curvature of the basic trajectory gradually and uniformly increases from zero to the set maximum curvature, and then gradually and uniformly decreases from the maximum curvature to zero. Then, the basic trajectory fitting circles generated by the multi-direction diffusion of the starting point and the target point are used, the tangents are determined using the relationship between the distance of the two centers and the sum of the radii, and the tangents whose directions are consistent with the heading of the corresponding circle at the tangent point are selected for trajectory connection. The problem of curvature discontinuity in traditional trajectory planning is effectively solved, the continuous connection of the trajectory curvature from the starting point to the target point is realized, and the control accuracy and motion stability are improved. At the same time, the maximum curvature and the curvature change rate are dynamic adjustable parameters, which can be dynamically set before planning according to different vehicles and trajectory requirements, meeting the diversified requirements of curvature characteristics in different scenarios and enhancing the flexibility and adaptability of trajectory planning.

[0061] In one embodiment, the method further comprises the following steps S1082-S1086:

[0062] Step S1082, for each overall planning trajectory, check whether it intersects with the environmental obstacles. If it intersects, discard the overall planning trajectory. If it does not intersect, mark the overall planning trajectory as a collision-free trajectory;

[0063] Step S1084, calculate the cost function of each collision-free trajectory by weighting;

[0064] Step S1086, select the collision-free trajectory with the minimum cost function value as the final executed planning trajectory.

[0065] The cost function includes the number of gear shifts and the length of the trajectory.

[0066] Specifically, collision detection and cost calculation are performed on all successfully calculated overall planning trajectories. The cost calculation uses a weighted approach to calculate the overall cost function, which includes the number of trajectory shifts and trajectory length. .in, Represents the weight coefficient. Finally, the trajectory with no collision and the minimum cost is selected as the output trajectory.

[0067] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0068] Based on the same inventive concept, the present application also provides a trajectory planning device for implementing the trajectory planning method mentioned above. The solution provided by the device is similar to the solution described in the above method. Therefore, the specific limitations of one or more trajectory planning device embodiments provided below can be found in the above limitations of the trajectory planning method, and will not be repeated here.

[0069] In one embodiment, Figure 7 As shown, a trajectory planning device is provided. The device includes:

[0070] A basic trajectory generation module 202 is configured to generate a basic trajectory based on dynamically set curvature-related parameters, wherein the curvature-related parameters include a maximum curvature and a curvature change rate. The basic trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with a fixed curvature, and a second spiral trajectory with decreasing curvature, wherein the curvature of the first spiral trajectory gradually increases from an initial value to a maximum curvature at a curvature change rate, the curvature of the circular arc trajectory is a maximum curvature, and the curvature of the second spiral trajectory gradually decreases from the maximum curvature to the initial value at a curvature change rate.

[0071] The basic trajectory combination module 204 is configured to generate multiple basic trajectories of the starting point by diffusing along multiple preset directions with the starting point as the center; generate multiple basic trajectories of the target point by diffusing along multiple preset directions with the target point as the center; and combine the basic trajectories of the starting point and the target point to form multiple trajectory combinations;

[0072] The whole trajectory planning module 206 is configured to, for the start point basis trajectory and the target point basis trajectory in each trajectory combination, fit the end point of the start point basis trajectory as a start circle, obtain the center and the radius of the circle, fit the end point of the target point basis trajectory as a target circle, obtain the center and the radius of the circle, determine the tangent corresponding to the two circles according to the relationship between the distance between the two centers and the sum of the two radii, screen the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point, intercept a sub-trajectory in the start point basis trajectory from the start point to the tangent point of the screened tangent on the start circle, intercept a sub-trajectory in the target point basis trajectory from the tangent point of the screened tangent on the target circle to the target point, connect the screened tangent with the intercepted start point basis sub-trajectory and the target point basis sub-trajectory, and form a whole planning trajectory.

[0073] In the trajectory planning device, the maximum curvature and the curvature change rate are dynamically configured, a basis trajectory composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with fixed curvature, and a second spiral trajectory with decreasing curvature is constructed. The first spiral trajectory and the second spiral trajectory are spiral trajectories with uniform curvature change at a fixed curvature change rate, so that the curvature of the basis trajectory gradually and uniformly increases from zero to the set maximum curvature, and then gradually and uniformly decreases from the maximum curvature to zero. Then, the basis trajectory fitting circles generated by the start point and the target point are used, the tangent is determined according to the relationship between the distance between the two centers and the sum of the radii, the tangent whose direction is consistent with the heading of the corresponding circle at the tangent point is screened, and the trajectory is connected, thereby effectively solving the problem of sudden change and discontinuity of curvature in traditional trajectory planning, realizing continuous connection of the trajectory curvature from the start point to the target point, and improving the control accuracy and motion stability. Meanwhile, the maximum curvature and the curvature change rate are dynamically adjustable parameters, which can be dynamically set before planning according to different vehicles and trajectory requirements, thereby meeting the diversified requirements for curvature characteristics in different scenarios and enhancing the flexibility and adaptability of trajectory planning.

[0074] It should be noted that the trajectory planning device provided in the above embodiments is only used as an example for the division of the above functional modules when realizing the corresponding functions. In actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the above described functions. In addition, the trajectory planning device and the trajectory planning method provided in the above embodiments belong to the same concept, and the specific implementation process is described in the method embodiments, which will not be described here.

[0075] According to an aspect of the present application, the embodiments of the present application further provide a computer program product, which comprises a computer program containing program codes for executing the method shown in the flow chart. In such embodiments, the computer program can be downloaded and installed from a network by a communication part. When the computer program is executed by a processor, the trajectory planning method provided by the embodiments of the present application is executed.

[0076] In addition, the embodiments of the present application further provide a computer device, which comprises a processor and a memory. The memory stores a computer program. The processor can execute the computer program stored in the memory. When the computer program is executed by the processor, the trajectory planning method provided by any of the above-mentioned embodiments can be implemented.

[0077] For example, Figure 8 A computer device provided by the embodiments of the present application is shown, which comprises a bus 1110, a processor 1120, a transceiver 1130, a bus interface 1140, a memory 1150 and a user interface 1160.

[0078] In the embodiments of the present application, the device further comprises a computer program stored in the memory 1150 and executable on the processor 1120. When the computer program is executed by the processor 1120, the processes of the trajectory planning method embodiments described above are implemented.

[0079] The transceiver 1130 is configured to receive and send data under the control of the processor 1120.

[0080] In the embodiments of the present application, the bus architecture (represented by the bus 1110) can include any number of interconnected buses and bridges. The bus 1110 connects various circuits including one or more processors represented by the processor 1120 and the memory represented by the memory 1150.

[0081] Bus 1110 represents one or more of any of several types of bus structures, including an address bus, a data bus, a control bus, a memory bus, and a storage bus, each of which can be implemented using various technologies and standards. Bus 1110 can include one or more buses implementing various bus standards, such as Industry Standard Architecture (ISA), Micro Channel Architecture (MCA), Extended ISA (EISA), Video Electronics Standards Association (VESA), and Peripheral Component Interconnect (PCI), to name a few.

[0082] Processor 1120 can be an integrated circuit chip located on a motherboard or a die containing logic for handling signals. In implementations, steps of the above-described method embodiments can be completed by integrated logic circuitry of the hardware or instructions of software in the processor. The processor described above includes a general-purpose processor, a central processing unit (CPU), a network processor (NP), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a complex programmable logic device (CPLD), a programmable logic array (PLA), a microcontroller unit (MCU), or other programmable logic device, discrete gate or transistor logic, discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed by the processor. For example, the processor can be a single-core processor or a multi-core processor, and the processor can be integrated into a single chip or located in multiple different chips.

[0083] The processor 1120 can be a microprocessor or any conventional processor. The disclosed method steps in conjunction with the embodiments of the present application can be directly executed by a hardware coded processor, or be executed by a combination of hardware and software modules in the coded processor. The software modules can be located in a readable storage medium such as random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), registers, or other known readable storage media in the art. The readable storage medium is located in the memory, and the processor reads the information in the memory to complete the steps of the above method in conjunction with its hardware.

[0084] The bus 1110 can also connect various other circuits such as peripheral devices, voltage stabilizers, or power management circuits, etc. The bus interface 1140 provides an interface between the bus 1110 and the transceiver 1130, which are well known in the art. Therefore, the embodiments of the present application will not be further described.

[0085] The transceiver 1130 can be one element or multiple elements, such as multiple receivers and transmitters, which provide a unit for communicating with various other devices on a transmission medium. For example, the transceiver 1130 receives external data from other devices, and the transceiver 1130 is used to send data processed by the processor 1120 to other devices. Depending on the nature of the computer system, a user interface 1160 can also be provided, such as a touch screen, a physical keyboard, a display, a mouse, a speaker, a microphone, a trackball, a joystick, a stylus.

[0086] It should be appreciated that in embodiments of the present application, the memory 1150 can further include a memory that is remote from the processor 1120, and the remote memory can be connected to a server through a network. One or more portions of the network can be an ad hoc network, an intranet, an extranet, a virtual private network (VPN), a local area network (LAN), a wireless LAN (WLAN), a wide area network (WAN), a wireless wide area network (WWAN), a metropolitan area network (MAN), the Internet, a public switched telephone network (PSTN), a public or private telephone network, a wireless phone network, a Wi-Fi network, and a combination of two or more of the aforementioned networks. For example, the wireless phone network and the wireless network can be a Global System for Mobile Communications (GSM) system, a Code Division Multiple Access (CDMA) system, a Worldwide Interoperability for Microwave Access (WiMAX) system, a General Packet Radio Service (GPRS) system, a Wideband Code Division Multiple Access (WCDMA) system, a Long Term Evolution (LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD) system, an LTE-Advanced (LTE-A) system, a Universal Mobile Telecommunications (UMTS) system, an Enhanced Mobile Broadband (eMBB) system, a massive Machine Type of Communication (mMTC) system, an Ultra Reliable Low Latency Communication (uRLLC) system, and the like.

[0087] It should be appreciated that the memory 1150 in embodiments of the present application can be a volatile memory or a non-volatile memory, or can include both a volatile memory and a non-volatile memory. Among them, the non-volatile memory includes a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically EPROM (EEPROM), or a Flash Memory.

[0088] The volatile memory includes random access memory (RAM), which acts to provide external cache to the processor. By way of example, and not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), synchronous Dynamic Random Access Memory (SDRAM), double-data rate synchronous DRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM). The memory 1150 of the subject embodiments includes, but is not limited to, those types as described above and any other suitable type of memory.

[0089] In the embodiments of the present application, the memory 1150 stores an operating system 1151 and an application program 1152, including executable modules, data structures, or subsets thereof, or expanded sets thereof.

[0090] In particular, the operating system 1151 includes various system programs, such as a framework layer, a core library layer, a driver layer, and the like, for implementing various basic services and processing hardware-based tasks. The application program 1152 includes various application programs, such as a media player, a browser, and the like, for implementing various application services. The program for implementing the method of the embodiments of the present application can be included in the application program 1152. The application program 1152 includes applets, objects, components, logic, data structures, and other computer system executable instructions for performing specific tasks or implementing specific abstract data types.

[0091] In addition, the embodiments of the present application also provide a computer readable storage medium, having stored thereon a computer program, which, when executed by a processor, implements each process of the trajectory planning method embodiments described above and achieves the same technical effects. To avoid repetition, details are not described here.

[0092] Computer-readable storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer-readable storage media includes, but is not limited to, RAM, ROM, EEPROM, solid state drives (SSDs), flash memory, phase-change memory (PRAM), other types of memory, other types of storage mediums, or any combination thereof. Computer-readable storage media does not include a transitory signal per se, but can be embodied in a computer-readable storage medium, such as a transitory signal propagating through a waveguide or other transmission media.

[0093] In the description of the present embodiments, those skilled in the art shall appreciate that the present embodiments can be implemented as methods, devices, apparatuses and storage media. Therefore, the present embodiments can be embodied in the form of entire hardware, entire software (including firmware, resident software, microcode, etc.), or a combination of hardware and software. In addition, in some embodiments, the present embodiments can also be embodied in the form of a computer program product in one or more computer-readable storage media, which includes computer program codes.

[0094] The above computer-readable storage medium can adopt any combination of one or more computer-readable storage media. The computer-readable storage medium includes an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or apparatus, or any combination thereof. More specific examples of the computer-readable storage medium include a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any combination thereof. In the present embodiments, the computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device or apparatus.

[0095] The computer program code embodied in the computer-readable storage medium described above can be transmitted using any appropriate medium, including but not limited to wireless, wired, optical fiber cable, Radio Frequency (RF), or any suitable combination thereof.

[0096] Computer program code for carrying out operations of embodiments of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0097] It should be understood that each block of the flowchart and / or block diagram illustrations, and combinations of blocks in the flowchart and / or block diagram illustrations, can be implemented by computer readable program instructions. These computer readable program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0098] These computer readable program instructions can also be stored in a computer readable storage medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable storage medium produce an article of manufacture including instructions which implement the function / act specified in the flowchart and / or block diagram block or blocks.

[0099] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0100] The above merely describes specific implementation manners of the embodiments of the present application, but the protection scope of the embodiments of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical region disclosed by the embodiments of the present application, and all should be covered in the protection scope of the embodiments of the present application. Therefore, the protection scope of the embodiments of the present application should be subject to the protection scope of the claims.

Claims

1. A trajectory planning method, characterized in that: The method comprises: Generate a basic trajectory based on dynamically set curvature-related parameters; wherein the curvature-related parameters include a maximum curvature and a curvature change rate; the basic trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with a fixed curvature, and a second spiral trajectory with decreasing curvature, the curvature of the first spiral trajectory gradually increasing from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreasing from the maximum curvature to the initial value at the curvature change rate; Taking the starting point as the center, multiple starting point basic trajectories are generated along multiple preset directions; taking the target point as the center, multiple target point basic trajectories are generated along multiple preset directions; combining the basic trajectories of the starting point and the target point to form multiple trajectory combinations; For the starting point basic trajectory and the target point basic trajectory in each trajectory combination, fit the end point of the starting point basic trajectory to the starting circle, obtain the center and radius of the circle, fit the end point of the target point basic trajectory to the target circle, obtain the center and radius of the circle, determine the corresponding tangents of the two circles according to the relationship between the distance between the two circle centers and the sum of the two circle radii, screen out the tangents whose directions are consistent with the headings of the corresponding circles at the tangent points, intercept the sub-trajectory from the starting point to the tangent point of the screened tangent on the starting circle in the starting point basic trajectory, intercept the sub-trajectory from the tangent point of the screened tangent on the target circle to the target point in the target point basic trajectory, connect the screened tangents with the corresponding intercepted starting point basic sub-trajectory and target point basic sub-trajectory to form the overall planning trajectory.

2. The method according to claim 1, characterized in that Generate basic trajectories based on dynamically set curvature-related parameters, including: Starting from the initial value of the curvature, the trajectory points are discretely sampled at fixed intervals, and arcs are constructed between adjacent points according to the current curvature. The curvature increases according to the curvature change rate until the curvature reaches the maximum curvature, thereby obtaining a first spiral trajectory.

3. The method according to claim 2, characterized in that Generates basic trajectory based on dynamically set curvature related parameters, including: After the curvature reaches the maximum curvature, the maximum curvature is kept unchanged, and the trajectory points are sampled according to a preset number of points to obtain an arc trajectory.

4. The method according to claim 3, characterized in that Generates basic trajectory based on dynamically set curvature related parameters, including: After the arc trajectory is generated, starting from the maximum curvature, the trajectory points are discretely sampled at fixed intervals, and arcs are constructed between adjacent points according to the current curvature. The curvature decreases according to the curvature change rate until the curvature falls back to the initial value, thereby obtaining a second spiral trajectory.

5. The method according to claim 4, characterized in that Taking the starting point as the center, multiple starting point basic trajectories are generated along multiple preset directions; taking the target point as the center, multiple target point basic trajectories are generated along multiple preset directions; Combine the basic trajectories of the starting point and the target point to form a variety of trajectory combinations, including: With the starting point as the center, four starting point basic trajectories are generated by spreading along the left front, right front, left back, and right back directions respectively; With the target point as the center, four basic trajectories of the target point are generated by spreading along the left front, right front, left back, and right back directions respectively; The four starting point basic trajectories and the four target point basic trajectories are combined to form sixteen trajectory combinations.

6. The method according to claim 5, characterized in that Based on the relationship between the distance between the two circle centers and the sum of the two circle radii, determine the corresponding tangent lines of the two circles, including: If the distance between the centers of the two circles is greater than the sum of the radii of the two circles, calculate the four tangents of the two circles; If the distance between the centers of the two circles is less than or equal to the sum of the radii of the two circles, calculate the two tangent lines of the two circles.

7. The method according to claim 6, characterized in that The method further comprises: For each overall planned trajectory, check whether it intersects with environmental obstacles. If so, discard the overall planned trajectory. If not, mark the overall planned trajectory as a collision-free trajectory. Calculating a cost function for each collision-free trajectory in a weighted manner; wherein the cost function includes the number of gear shifts and the trajectory length; The collision-free trajectory with the smallest cost function value is selected as the final planned trajectory.

8. A trajectory planning device, characterized in that: The device comprises: a basic trajectory generation module, configured to generate a basic trajectory based on dynamically set curvature-related parameters; wherein the curvature-related parameters include a maximum curvature and a curvature change rate; the basic trajectory is composed of a first spiral trajectory with increasing curvature, a circular arc trajectory with a fixed curvature, and a second spiral trajectory with decreasing curvature, the curvature of the first spiral trajectory gradually increasing from an initial value to the maximum curvature at the curvature change rate, the curvature of the circular arc trajectory is the maximum curvature, and the curvature of the second spiral trajectory gradually decreasing from the maximum curvature to the initial value at the curvature change rate; The basic trajectory combination module is used to generate multiple basic trajectories of the starting point along multiple preset directions with the starting point as the center; to generate multiple basic trajectories of the target point along multiple preset directions with the target point as the center; and to combine the basic trajectories of the starting point and the target point to form multiple trajectory combinations; The overall trajectory planning module is used to fit the end point of the starting point basic trajectory and the target point basic trajectory in each trajectory combination into a starting circle, obtain the center and radius of the circle, fit the end point of the target point basic trajectory into a target circle, obtain the center and radius of the circle, determine the corresponding tangents of the two circles according to the relationship between the distance between the two circle centers and the sum of the two circle radii, screen out the tangents whose directions are consistent with the headings of the corresponding circles at the tangent points, intercept the sub-trajectory from the starting point to the tangent point of the screened tangent on the starting circle in the starting point basic trajectory, intercept the sub-trajectory from the tangent point of the screened tangent on the target circle to the target point in the target point basic trajectory, connect the screened tangents with the corresponding intercepted starting point basic sub-trajectory and target point basic sub-trajectory to form an overall planning trajectory.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, 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 7 are implemented.

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