Unmanned vehicle path planning method, device, electronic equipment, unmanned vehicle and medium

Abstract

The embodiment of the present invention discloses a method, device, electronic device, unmanned vehicle and medium for path planning of an unmanned vehicle, the method comprising: when detecting that the target path planning in the current first coordinate system fails, determining the second position coordinate of the unmanned vehicle in the second coordinate system according to the first position coordinate of the unmanned vehicle in the current first coordinate system, the second coordinate system comprising coordinate axes along the center line of the road and perpendicular to the center line of the road respectively; in the second coordinate system, generating an alternative path connecting the second position coordinate and the center line of the road, wherein the alternative path is a monotonic curve; controlling the unmanned vehicle to travel along the alternative path from the second position coordinate to the center line of the road, and travel to the destination along the current target path. The problem of low success rate of path planning in complex scenes of existing unmanned vehicle technology is solved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of unmanned vehicle control, and in particular to an unmanned vehicle path planning method, device, electronic equipment, unmanned vehicle and medium. Background Art

[0002] At present, mobile robot technology is developing rapidly. With the increasing number of robot application scenarios and modes, various mobile robots have emerged, and unmanned vehicles are one of them. Under normal circumstances, the path planning module of unmanned vehicles can output a safe and feasible path, but in more complex environments, path planning may fail.

[0003] In summary, in the process of implementing the present invention, the inventors found that there are at least the following technical problems in the prior art: when existing unmanned vehicles encounter path planning failures, the strategy usually adopted is to reuse the path planned in the previous frame, but the success rate of this strategy in complex scenarios is still low. Summary of the invention

[0004] The embodiments of the present invention provide an unmanned vehicle path planning method, device, electronic device, unmanned vehicle and medium, which solve the problem of low path planning success rate in complex scenarios of existing unmanned vehicle technology.

[0005] In a first aspect, an embodiment of the present invention provides a method for unmanned vehicle path planning, comprising:

[0006] When it is detected that the target path planning in the first coordinate system fails, determining the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system, wherein the second coordinate system includes coordinate axes respectively along the center line of the road and perpendicular to the center line of the road;

[0007] In the second coordinate system, generating an alternative path connecting the second position coordinates and the center line of the road, wherein the alternative path is a monotonic curve;

[0008] The unmanned vehicle is controlled to travel along the alternative path from the second position coordinate to the center line of the road, and travel to the destination along the current target path.

[0009] In a second aspect, an embodiment of the present invention further provides a path planning device for an unmanned vehicle, comprising:

[0010] A coordinate conversion module, configured to determine, when detecting that the target path currently in the first coordinate system fails, a second position coordinate of the unmanned vehicle in a second coordinate system according to the first position coordinate of the unmanned vehicle currently in the first coordinate system, wherein the second coordinate system includes coordinate axes respectively along a center line of the road and perpendicular to the center line of the road;

[0011] An alternative path module, used for generating an alternative path connecting the second position coordinates and the center line of the road in a second coordinate system; wherein the alternative path is a monotonic curve;

[0012] The driving module is used to control the unmanned vehicle to drive from the second position coordinates along the alternative path to the center line of the road, and to drive to the destination along the current target path.

[0013] In a third aspect, an embodiment of the present invention further provides an electronic device, including:

[0014] one or more processors;

[0015] A memory for storing one or more programs;

[0016] When the one or more programs are executed by the one or more processors, the one or more processors implement the unmanned vehicle path planning method described in any embodiment.

[0017] In a fourth aspect, an embodiment of the present invention further provides an unmanned vehicle, comprising:

[0018] Vehicle body;

[0019] A traveling mechanism, arranged on the vehicle body, and used for driving the vehicle body to travel;

[0020] A processor is used to determine the second position coordinates of the unmanned vehicle in a second coordinate system based on the first position coordinates of the unmanned vehicle in the first coordinate system when a target path planning failure is detected, wherein the second coordinate system includes coordinate axes along a road centerline and perpendicular to the road centerline respectively; generate an alternative path connecting the second position coordinates and the road centerline in the second coordinate system; wherein the alternative path is a monotonic curve; and control a traveling mechanism to drive the vehicle body along the alternative path from the second position coordinates to the road centerline, and travel to the destination along the current target path.

[0021] In a fifth aspect, an embodiment of the present invention further provides a storage medium comprising computer executable instructions, which, when executed by a computer processor, are used to execute the unmanned vehicle path planning method described in any embodiment.

[0022] The technical solution of the unmanned vehicle path planning method provided by an embodiment of the present invention determines the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system when it is detected that the current target path planning in the first coordinate system fails; in the second coordinate system, an alternative path with the second position coordinates as the starting point is generated, and the alternative path is a monotonic curve, which can guide the unmanned vehicle to travel from the second position coordinates to the center line of the road, thereby quickly escaping from the current complex scene; the unmanned vehicle that returns to the center line of the road travels along the current target path to the destination, and can reach the destination accurately and safely. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 is a flow chart of the unmanned vehicle path planning method provided by the first embodiment of the present invention;

[0025] Figure 2 It is a road schematic diagram provided by the first embodiment of the present invention in both the Cartesian coordinate system and the Frenet coordinate system;

[0026] Figure 3 This is a schematic diagram of alternative paths provided in the first embodiment of the present invention;

[0027] Figure 4 is a structural block diagram of an unmanned vehicle path planning device provided in Embodiment 2 of the present invention;

[0028] Figure 5 is a structural block diagram of an electronic device provided by Embodiment 3 of the present invention;

[0029] Figure 6 This is a structural block diagram of an unmanned vehicle provided in Embodiment 4 of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described through implementation methods with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Embodiment 1

[0032] Figure 1 : is a flow chart of the unmanned vehicle path planning method provided in the first embodiment of the present invention. The technical solution of this embodiment is applicable to the case where the unmanned vehicle quickly returns to the center line of the road through an alternative path when the target path planning fails. The method can be executed by the unmanned vehicle path planning device provided in the embodiment of the present invention, which can be implemented in software and / or hardware and configured in the controller of the unmanned vehicle. The method specifically includes the following steps:

[0033] S101. When it is detected that the target path planning in the first coordinate system fails, the second position coordinates of the unmanned vehicle in the second coordinate system are determined according to the first position coordinates of the unmanned vehicle in the first coordinate system, and the second coordinate system includes coordinate axes along the center line of the road and perpendicular to the center line of the road.

[0034] The target path planning failure includes the unmanned vehicle deviating from the center line of the road, and the distance from the edge of the road is within the preset warning range. The first coordinate system includes but is not limited to the Cartesian coordinate system and the UTM (Universal Transverse Mercator Grid System, referred to as UTM, Universal Transverse Mercator Grid System) coordinate system. The second coordinate system is preferably but not limited to the frenet coordinate system, as long as it includes coordinate axes along the center line of the road and perpendicular to the center line of the road.

[0035] Take the case where the first coordinate system is a Cartesian coordinate system and the second coordinate system is a Frenet coordinate system. If the road is complex, for example, the road is particularly curved, it is difficult to quickly plan a target path that is completely along the center line of the road in the Cartesian coordinate system. If the target path is not completely along the center line of the road, the unmanned vehicle will deviate from the center line of the road and drive toward the edge of the road when driving along the target path. Once this situation occurs and is not resolved in time, the unmanned vehicle will run off the road. To this end, this embodiment determines the second position coordinates of the unmanned vehicle in the Frenet coordinate system based on the first position coordinates of the unmanned vehicle in the Cartesian coordinate system, that is, quickly switches from the current Cartesian coordinate system to the Frenet coordinate system.

[0036] In one embodiment, the method for switching between the Cartesian coordinate system and the Frenet coordinate system is as follows: Figure 2 As shown, the Cartesian coordinate system is yMx, and the frenet coordinate system is SL. In the frenet coordinate system, the S axis is along the direction of the road centerline 11, and the L axis is perpendicular to the road centerline 11. The road centerline is composed of a series of discrete points. The coordinates of each discrete point in the Cartesian coordinate system can be expressed as r i (x i ,y i ,θ i ,kappa i,dkappa i ),i=1,2,...,n, where x i Represents the horizontal coordinate value of the discrete point in the Cartesian coordinate system, y i Represents the ordinate value of a discrete point in the Cartesian coordinate system, θ i represents the orientation angle of the discrete point in the Cartesian coordinate system; kappa represents the curvature corresponding to the discrete point in the Cartesian coordinate system, and dkappa represents the curvature change rate corresponding to the discrete point in the Cartesian coordinate system. Set the coordinates of the discrete point p in the Cartesian coordinate system to p(x p ,y p ,θ p ,kappa p ,dkappa p ), the coordinates of the point p in the Frenet coordinate system are (s p ,l p ,l p ',l p ”). Determine the two discrete points s(x) closest to the discrete point p on the center line of the road. s ,y s ,θ s ,kappa s ,dkappa s ) and e(x e ,y e ,θ e ,kappa e ,dkappa e ), set the coordinates of discrete point s in the Frenet coordinate system to (s s ,0.0,0.0,0.0), the coordinates of the discrete point e in the Frenet coordinate system are (s e ,0.0,0.0,0.0), then:

[0037] The vector from discrete point s to discrete point p can be expressed as:

[0038]

[0039] The vector from discrete point e to discrete point p can be expressed as:

[0040]

[0041] The vector is calculated by the following formula With vector Conversion factor between

[0042]

[0043]

[0044] Therefore, p It can be expressed as:

[0045]

[0046] l p It can be expressed as:

[0047]

[0048] Assume that the coordinates of the projection point of the discrete point p on the road centerline in the Cartesian coordinate system are r(x r ,y r ,θ r ,kappa r ,dkappa r ), we can get:

[0049]

[0050] From formula (6) and formula (7), we can get:

[0051]

[0052]

[0053] In summary, according to formulas (5), (6), (8) and (9), the first position coordinates in the Cartesian coordinate system can be converted to the second position coordinates in the Frenet coordinate system.

[0054] S102. In a second coordinate system, generate an alternative path connecting the second position coordinates and the center line of the road, wherein the alternative path is a monotonic curve.

[0055] Since the S axis of the frenet coordinate system is always along the road centerline, the road centerline can be quickly located by the S axis along the road centerline in the frenet coordinate system. Then, according to the distribution of the second position coordinates and the road centerline, an alternative path 2 connecting the second position coordinates and the road centerline 11 is planned (see Figure 3 ), and the alternative path 2 is a monotonic curve.

[0056] In some embodiments, see Figure 3 In the direction along the second position coordinate to the intersection of the alternative path and the road centerline, the coordinate values ​​of each discrete point of the alternative path on the S axis (direction of the road centerline) increase uniformly, the distance between each discrete point of the alternative path and the road centerline decreases uniformly, and the curvature and curvature change rate of each discrete point decrease uniformly.

[0057] Exemplarily, each discrete point on the alternative path can be expressed as:

[0058]

[0059] Among them, i is the index number of the discrete point on the alternative path, s i is the position of the discrete point with index number i on the alternative path in the direction parallel to the centerline of the road, l i is the position of the discrete point with index number i on the alternative path in the direction perpendicular to the centerline of the road, l′ i is the curvature of the alternative path corresponding to the discrete point with index number i on the alternative path, l″ i is the curvature change rate of the alternative path corresponding to the coordinate point with index number i on the alternative path, (s p , l p , l' p , l″ p ) is the coordinate of the second position, s p is the value of the second position coordinate on the S axis, l p is the value of the second position coordinate on the l-axis, l' p is the curvature corresponding to the second position coordinate, l″ p is the curvature change rate corresponding to the second position coordinate; N is the total number of discrete points on the alternative path, and the index number gradually increases in the direction from the second position coordinate to the alternative path and the center line of the road.

[0060] From formula (10) and Figure 3 It can be seen that the alternative path From the appearance, it is a smooth path that gradually progresses from the second position coordinate to the center line of the road, and the arc center direction of each arc portion contained therein is consistent with the arc center direction of each arc portion of the corresponding road center line. Figure 3 The alternative path in includes two arc parts, and the arc center direction of each arc part is consistent with the arc center direction of the corresponding road center line. It can be understood that the trend of the alternative path is consistent with the trend of the road center line. When the road center line is a straight line, the alternative path is also a straight line; when the road center line near the unmanned vehicle has only one arc part, the alternative path also has only one arc part; when the road center line near the unmanned vehicle is composed of two arc parts, that is, the unmanned vehicle currently corresponds to an arc part of the road center line, but cannot complete the operation of returning to the road center line near the arc part, and needs to enter the road center line at the next arc part, the alternative path also has two arc parts, and the arc center direction of each arc part of the alternative path is consistent with the arc center direction of the arc part of the corresponding road center line.

[0061] S103: Control the unmanned vehicle to travel from the second position coordinates to the center line of the road along the alternative path, and travel to the destination along the current target path.

[0062] Set the alternate path as the current path, see Figure 3 As shown, the unmanned vehicle 3 is controlled to travel along the alternative path 2 from the second position coordinate to the road center line 11 to escape from the current complex situation, so that it can travel to the destination along the current target path. Figure 3 It is also shown that when the unmanned vehicle 3 travels along the alternative path to the road centerline 11 , the orientation angle of the unmanned vehicle 3 is the same as the direction of the road centerline 11 .

[0063] In some embodiments, the road on which the unmanned vehicle is traveling has a serious road curvature only near the second position coordinate and the alternative path. Then, when the unmanned vehicle enters the center line of the road along the alternative path, it can be considered that the unmanned vehicle has returned to the original target path. At this time, the original target path is still used as the current target path, and the unmanned vehicle is controlled to continue traveling along the original target path; or the intersection of the alternative path and the center line of the road is used as the starting point, and the target path is replanned in the Cartesian coordinate system or the Frenet coordinate system to update the target path, and the unmanned vehicle is controlled to continue traveling to the destination along the updated target path, so that the destination can be reached accurately and safely.

[0064] In some embodiments, if there are a large number of curved sections on the road that the unmanned vehicle is traveling on, the intersection of the alternative path and the center line of the road is used as the starting point, and the target path is replanned in the Frenet coordinate system, and the target path is always along the center line of the road. When the unmanned vehicle travels from the alternative path to the center line of the road, the replanned target path is used as the current target path, and the unmanned vehicle is controlled to travel along the current target path to the destination.

[0065] The technical solution of the unmanned vehicle path planning method provided by an embodiment of the present invention determines the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system when it is detected that the current target path planning in the first coordinate system fails; in the second coordinate system, an alternative path connecting the second position coordinates and the center line of the road is generated, and the alternative path is a monotonic curve, which can guide the unmanned vehicle to travel from the second position coordinates to the center line of the road, thereby quickly escaping from the current complex scene; the unmanned vehicle that returns to the center line of the road travels along the current target path to the destination, and can reach the destination accurately and safely.

[0066] Embodiment 2

[0067] Figure 4 : is a structural block diagram of the unmanned vehicle path planning device provided in the second embodiment of the present invention. The device is used to execute the unmanned vehicle path planning method provided in any of the above embodiments, and the device can be implemented in software or hardware. The device includes

[0068] A coordinate conversion module 41 is used to determine the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system when it is detected that the target path currently in the first coordinate system fails, wherein the second coordinate system includes coordinate axes respectively along the center line of the road and perpendicular to the center line of the road;

[0069] The alternative path module 42 is used to generate an alternative path connecting the second position coordinates and the center line of the road in the second coordinate system; wherein the alternative path is a monotonic curve;

[0070] The operation module 43 is used to control the unmanned vehicle to travel along the alternative path from the second position coordinate to the center line of the road, and travel to the destination along the current target path.

[0071] Optionally, the target path planning failure includes the unmanned vehicle deviating from the center line of the road and the distance from the edge of the road being within a preset warning range.

[0072] Optionally, the operation module 43 is used to control the unmanned vehicle to travel along an alternative path from the second position coordinate to the center line of the road, and to re-plan the target path with the intersection of the alternative path and the center line of the road as the starting point; when it is detected that the unmanned vehicle travels to the center line of the road, the unmanned vehicle is controlled to travel along the current target path to the destination.

[0073] Optionally, in the direction from the second position coordinate to the intersection of the alternative path and the road centerline, the curvature and curvature change rate of each discrete point of the alternative path, and the distance between each discrete point and the road centerline, respectively decrease uniformly.

[0074] Optionally, each discrete point on the alternative path is represented as:

[0075]

[0076] Among them, i is the index number of the discrete point on the alternative path, s i is the position of the discrete point with index number i on the alternative path in the direction parallel to the centerline of the road, l i is the position of the discrete point with index number i on the alternative path in the direction perpendicular to the centerline of the road, l′ i is the curvature of the alternative path corresponding to the discrete point with index number i on the alternative path, l″ i is the curvature change rate of the alternative path corresponding to the coordinate point with index number i on the alternative path, s p is the value of the second position coordinate on the s axis, l p is the value of the second position coordinate on the l-axis, l' p is the curvature corresponding to the second position coordinate, l″ p is the curvature change rate corresponding to the second position coordinate; N is the total number of discrete points on the alternative path.

[0077] Optionally, the second coordinate system is a Frenet coordinate system.

[0078] The technical solution of the unmanned vehicle path planning device provided by an embodiment of the present invention determines the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system when detecting that the current target path planning in the first coordinate system fails through the coordinate conversion module; generates an alternative path connecting the second position coordinates and the center line of the road in the second coordinate system through the alternative path module, and the alternative path is a monotonic curve, which can guide the unmanned vehicle to drive quickly and safely from the second position coordinates to the center line of the road, thereby quickly escaping from the current complex scene; the unmanned vehicle that returns to the center line of the road can accurately and safely reach the destination by driving along the current target path to the destination.

[0079] The unmanned vehicle path planning device provided in the embodiment of the present invention can execute the unmanned vehicle path planning method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0080] Embodiment 3

[0081] Figure 5 A schematic diagram of the structure of an electronic device provided in Embodiment 3 of the present invention is shown in FIG. Figure 5 As shown, the device includes a processor 501, a memory 502, an input device 503, and an output device 504; the number of processors 501 in the device can be one or more. Figure 5 A processor 501 is taken as an example; the processor 501, the memory 502, the input device 503 and the output device 504 in the device can be connected by a bus or other means. Figure 5 The example of connecting through bus is taken in the following.

[0082] The memory 502, as a computer-readable storage medium, can be used to store software programs, computer executable programs and modules, such as program instructions / modules corresponding to the unmanned vehicle path planning method in the embodiment of the present invention (for example, the coordinate conversion module 41, the alternative path module 42 and the driving module 43). The processor 501 executes various functional applications and data processing of the device by running the software programs, instructions and modules stored in the memory 502, that is, realizing the above-mentioned unmanned vehicle path planning method.

[0083] The memory 502 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system and at least one application required for a function; the data storage area may store data created according to the use of the terminal, etc. In addition, the memory 502 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some instances, the memory 502 may further include a memory remotely arranged relative to the processor 501, and these remote memories may be connected to the device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0084] The input device 503 may be used to receive input digital or character information, and to generate key signal input related to user settings and function control of the device.

[0085] The output device 504 may include a display device such as a display screen, for example, a display screen of a user terminal.

[0086] Embodiment 4

[0087] Figure 6 This is a schematic diagram of the structure of the unmanned vehicle provided in the fourth embodiment of the present invention. The unmanned vehicle can quickly return to the center line of the road through an alternative path when the target path planning fails. Figure 6 As shown, the unmanned vehicle includes a vehicle body, a traveling mechanism 6 for driving the vehicle body, and a processor 501 connected to the traveling mechanism, wherein the processor 501 is used to determine the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system when detecting that the target path planning fails, the second coordinate system includes coordinate axes along the center line of the road and perpendicular to the center line of the road respectively; in the second coordinate system, generate an alternative path connecting the second position coordinates and the center line of the road; wherein the alternative path is a monotonic curve; and control the traveling mechanism to drive the vehicle body along the alternative path from the second position coordinates to the center line of the road, and continue to travel to the destination along the current target path.

[0088] The target path planning failure includes the unmanned vehicle deviating from the center line of the road, and the distance from the edge of the road is within the preset warning range. The first coordinate system includes but is not limited to the Cartesian coordinate system and the UTM (Universal Transverse Mercator Grid System, referred to as UTM, Universal Transverse Mercator Grid System) coordinate system. The second coordinate system is preferably but not limited to the frenet coordinate system, as long as it includes coordinate axes along the center line of the road and perpendicular to the center line of the road.

[0089] Take the case where the first coordinate system is a Cartesian coordinate system and the second coordinate system is a Frenet coordinate system. If the road is complex, for example, the road is particularly curved, it is difficult to quickly plan a target path that is completely along the center line of the road in the Cartesian coordinate system. If the target path is not completely along the center line of the road, then when the unmanned vehicle travels along the target path, it will deviate from the center line of the road and drive toward the edge of the road. Once this situation occurs and is not resolved in time, the unmanned vehicle will run off the road. To this end, this embodiment determines the second position coordinates of the unmanned vehicle in the Frenet coordinate system based on the first position coordinates of the unmanned vehicle in the Cartesian coordinate system, that is, quickly switches from the current Cartesian coordinate system to the Frenet coordinate system.

[0090] Since the S axis of the frenet coordinate system is always along the road centerline, the road centerline can be quickly located by the S axis along the road centerline in the frenet coordinate system, and then an alternative path connecting the second position coordinates and the road centerline is planned according to the distribution of the second position coordinates and the road centerline (see Figure 3 ), and the alternative path is a monotonic curve.

[0091] In some embodiments, in the direction from the second position coordinate to the intersection of the alternative path and the road centerline, the curvature and curvature change rate of each discrete point of the alternative path, and the distance between each discrete point and the road centerline, respectively decrease uniformly.

[0092] Exemplarily, each discrete point on the alternative path can be expressed as:

[0093]

[0094] Among them, i is the index number of the discrete point on the alternative path, s i is the position of the discrete point with index number i on the alternative path in the direction parallel to the centerline of the road, l i is the position of the discrete point with index number i on the alternative path in the direction perpendicular to the centerline of the road, l i ' is the curvature of the alternative path corresponding to the discrete point with index number i on the alternative path, l" i is the curvature change rate of the alternative path corresponding to the coordinate point with index number i on the alternative path, (s p , l p , l' p , l″ p ) is the coordinate of the second position, s p is the value of the second position coordinate on the S axis, l p is the value of the second position coordinate on the l-axis, l' p is the curvature corresponding to the second position coordinate, l″ pis the curvature change rate corresponding to the second position coordinate; N is the total number of discrete points on the alternative path, and the index number gradually increases in the direction from the second position coordinate to the alternative path and the center line of the road.

[0095] From formula (10) and Figure 3 It can be seen that the alternative path From the appearance, it is a smooth path that gradually progresses from the second position coordinate to the center line of the road, and the arc center direction of each arc contained therein is consistent with the arc center direction of the corresponding arc of the center line of the road. Figure 3 The alternative path in includes two arcs, and the arc center direction of each arc is consistent with the arc center direction of the corresponding road center line. It can be understood that the trend of the alternative path is consistent with the trend of the road center line. When the road center line is a straight line, the alternative path is also a straight line; when there is only one arc on the road center line near the unmanned vehicle, the alternative path also has only one arc; when the road center line near the unmanned vehicle is composed of two arcs, that is, the unmanned vehicle currently corresponds to an arc of the road center line, but cannot complete the operation of returning to the road center line near the arc, and needs to enter the road center line at the next arc. At this time, the alternative path also has two arcs, and the arc center direction of each arc of the alternative path is consistent with the arc center direction of the arc corresponding to the road center line.

[0096] The alternative path is used as the current path, and the driving mechanism is controlled to drive the vehicle body along the alternative path from the second position coordinate to the center line of the road, so as to escape from the current complex situation and drive to the destination along the current target path.

[0097] In some embodiments, the road on which the unmanned vehicle is traveling has a serious road curvature only near the second position coordinate and the alternative path. Then, when the unmanned vehicle enters the center line of the road along the alternative path, it can be considered that the unmanned vehicle has returned to the original target path. At this time, the target path is still used as the current target path, and the unmanned vehicle is controlled to continue traveling along the original target path; or the intersection of the alternative path and the center line of the road is used as the starting point, and the target path is replanned in the Cartesian coordinate system or the Frenet coordinate system to update the target path, and the unmanned vehicle is controlled to continue traveling along the updated target path, so that the destination can be reached accurately and safely.

[0098] In some embodiments, if there are a large number of curved sections on the road that the unmanned vehicle is traveling on, the intersection of the alternative path and the center line of the road is used as the starting point, and the target path is replanned in the Frenet coordinate system, and the target path is always along the center line of the road. When the unmanned vehicle travels from the alternative path to the center line of the road, the replanned target path is used as the current target path, and the unmanned vehicle is controlled to travel along the current target path.

[0099] The technical solution for the unmanned vehicle provided by an embodiment of the present invention determines the second position coordinates of the unmanned vehicle in the second coordinate system based on the first position coordinates of the unmanned vehicle in the first coordinate system when it detects that the current target path planning in the first coordinate system fails; in the second coordinate system, an alternative path connecting the second position coordinates and the center line of the road is generated, and the alternative path is a monotonic curve, which can guide the unmanned vehicle to travel from the second position coordinates to the center line of the road, thereby quickly escaping from the current complex scene; the unmanned vehicle that returns to the center line of the road travels along the current target path to the destination, and can reach the destination accurately and safely.

[0100] Embodiment 5

[0101] Embodiment 5 of the present invention further provides a storage medium containing computer executable instructions, wherein the computer executable instructions are used to execute a method for unmanned vehicle path planning when executed by a computer processor, the method comprising:

[0102] When it is detected that the target path planning in the first coordinate system fails, determining the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system, wherein the second coordinate system includes coordinate axes respectively along the center line of the road and perpendicular to the center line of the road;

[0103] In the second coordinate system, generating an alternative path connecting the second position coordinates and the center line of the road, wherein the alternative path is a monotonic curve;

[0104] The unmanned vehicle is controlled to travel along the alternative path from the second position coordinate to the center line of the road, and travel to the destination along the current target path.

[0105] Of course, the storage medium containing computer executable instructions provided in an embodiment of the present invention is not limited to the method operations described above, and can also execute related operations in the unmanned vehicle path planning method provided in any embodiment of the present invention.

[0106] Through the above description of the implementation method, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to execute the unmanned vehicle path planning method described in each embodiment of the present invention.

[0107] It is worth noting that in the above-mentioned embodiment of the unmanned vehicle path planning device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be realized; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention.

[0108] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for unmanned vehicle path planning, characterized in that: include: When it is detected that the target path planning in the first coordinate system fails, determining the second position coordinates of the unmanned vehicle in the second coordinate system according to the first position coordinates of the unmanned vehicle in the first coordinate system, wherein the second coordinate system includes coordinate axes respectively along the center line of the road and perpendicular to the center line of the road; In the second coordinate system, an alternative path connecting the second position coordinate and the center line of the road is generated, wherein the alternative path is a monotonic curve, and the expression of the alternative path is: Each discrete point on the alternative path can be expressed as: Among them, i is the index number of the discrete point on the alternative path, s i is the position of the discrete point with index number i on the alternative path in the direction parallel to the centerline of the road, l i is the position of the discrete point with index number i on the alternative path in the direction perpendicular to the centerline of the road, l i ' is the curvature of the alternative path corresponding to the discrete point with index number i on the alternative path, l i ” is the curvature change rate of the alternative path corresponding to the coordinate point with index number i on the alternative path; The unmanned vehicle is controlled to travel along the alternative path from the second position coordinate to the center line of the road, and travel to the destination along the current target path.

2. The method according to claim 1, characterized in that The target path planning failure includes: the unmanned vehicle deviates from the center line of the road and the distance from the edge of the road is within a preset warning range.

3. The method according to claim 1, characterized in that The controlling the unmanned vehicle to travel from the second position coordinates along the alternative path to the center line of the road, and to travel to the destination along the current target path, includes: Controlling the unmanned vehicle to travel along the alternative path from the second position coordinate to the center line of the road, and replanning the target path with the intersection of the alternative path and the center line of the road as the starting point; When it is detected that the unmanned vehicle has reached the center line of the road, the unmanned vehicle is controlled to travel along the current target path toward the destination.

4. The method according to any one of claims 1 to 3, characterized in that: The second coordinate system is a frenet coordinate system.

5. A path planning device for an unmanned vehicle, characterized in that: include: A coordinate conversion module, configured to determine, when detecting that the target path currently in the first coordinate system fails, a second position coordinate of the unmanned vehicle in a second coordinate system according to the first position coordinate of the unmanned vehicle currently in the first coordinate system, wherein the second coordinate system includes coordinate axes respectively along a center line of the road and perpendicular to the center line of the road; The alternative path module is used to generate an alternative path connecting the second position coordinate and the center line of the road in a second coordinate system; wherein the alternative path is a monotonic curve, and the expression of the alternative path is: Each discrete point on the alternative path can be expressed as: Among them, i is the index number of the discrete point on the alternative path, s i is the position of the discrete point with index number i on the alternative path in the direction parallel to the centerline of the road, l i is the position of the discrete point with index number i on the alternative path in the direction perpendicular to the centerline of the road, l i ' is the curvature of the alternative path corresponding to the discrete point with index number i on the alternative path, l i ” is the curvature change rate of the alternative path corresponding to the coordinate point with index number i on the alternative path; The operation module is used to control the unmanned vehicle to travel along the alternative path from the second position coordinate to the center line of the road, and travel to the destination along the current target path.

6. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the unmanned vehicle path planning method as described in any one of claims 1-4.

7. An unmanned vehicle, characterized in that: include: Vehicle body; A traveling mechanism, arranged on the vehicle body, and used for driving the vehicle body to travel; A processor, configured to determine, when a target path planning failure is detected, a second position coordinate of the unmanned vehicle in a second coordinate system according to the first position coordinate of the unmanned vehicle in the first coordinate system, wherein the second coordinate system includes coordinate axes along a road centerline and perpendicular to the road centerline respectively; generate an alternative path connecting the second position coordinate and the road centerline in the second coordinate system; and control a travel mechanism to drive the vehicle body along the alternative path from the second position coordinate to the road centerline, and travel to a destination along the current target path; wherein the alternative path is a monotonic curve, and the expression of the alternative path is: Each discrete point on the alternative path can be expressed as: Among them, i is the index number of the discrete point on the alternative path, s i is the position of the discrete point with index number i on the alternative path in the direction parallel to the centerline of the road, l i is the position of the discrete point with index number i on the alternative path in the direction perpendicular to the centerline of the road, l i ' is the curvature of the alternative path corresponding to the discrete point with index number i on the alternative path, l i ” is the curvature change rate of the alternative path corresponding to the coordinate point with index number i on the alternative path.

8. A storage medium containing computer executable instructions, characterized in that: The computer executable instructions, when executed by a computer processor, are used to execute the unmanned vehicle path planning method as described in any one of claims 1-4.

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