Loader track generation method and device, electronic equipment and readable storage medium

Abstract

The invention discloses a loader track generation method and device, electronic equipment and a readable storage medium, and the method comprises the steps: obtaining an initial pose and a terminal pose of a loader, the initial pose and the terminal pose including position coordinates and direction angles; establishing a two-dimensional coordinate system by taking the initial pose as an original point, and determining a target pose of the end point pose in the two-dimensional coordinate system; making a first ray along the reverse direction of the direction angle in the target pose, and determining an intersection point of the first ray and the X axis under the condition that the first ray intersects with the X axis; and according to the size of the X-axis coordinate of the intersection point, generating a target driving track containing at least one double-clothoid curve of which the maximum curvature is less than or equal to a preset curvature threshold value between the initial pose and the target pose. According to the method, the loading machine traveling track is generated based on the double clothoids, the situation that the curvature of the loading machine traveling track exceeds the curvature of the turning track when the loading machine turns at the maximum turning angle is avoided, and the traveling safety is greatly improved.

Description

Technical Field

[0001] The present application relates to the field of mechanical control, and in particular to a loader trajectory generation method, device, electronic device and computer-readable storage medium. Background Art

[0002] A loader is a kind of engineering machinery used for material handling and loading. It has the characteristics of good mobility, high loading efficiency, and easy operation. Automated unmanned loaders can complete operations autonomously without human intervention, thereby improving loading efficiency and operating efficiency. In the operation process of unmanned loaders, mobile navigation occupies the vast majority, so the trajectory generation required for navigation is also the most basic and critical link.

[0003] In the related art, an offline deployment method based on a straight line, an arc line, a Bezier curve, a spline curve, etc. is usually adopted to generate a driving trajectory, and the unmanned loader travels along the generated driving trajectory.

[0004] However, due to the special hinge structure of the loader itself, its maximum steering angle is subject to certain restrictions. The curvature of the loader's driving track generated by the above-mentioned related technology may exceed the curvature of the turning track when the loader turns at the maximum steering angle, so the driving track generated by the above-mentioned related technology has a great driving safety hazard. Summary of the invention

[0005] The present application provides a loader trajectory generation method, device, electronic device and computer-readable storage medium to solve the problem that the curvature of the loader driving trajectory generated by the prior art exceeds the curvature of the turning trajectory when the loader turns at a maximum steering angle.

[0006] In a first aspect, an embodiment of the present application provides a method for generating a loader trajectory, the method comprising:

[0007] Acquire an initial position and a terminal position of the loader, wherein the initial position and the terminal position include position coordinates and direction angles;

[0008] Establishing a two-dimensional coordinate system with the initial posture as the origin, and determining the target posture of the end posture in the two-dimensional coordinate system;

[0009] Make a first ray in the opposite direction of the direction angle in the target posture, and when the first ray intersects the X-axis, determine the intersection point of the first ray and the X-axis;

[0010] According to the size of the X-axis coordinate of the intersection, a target driving trajectory is generated between the initial posture and the target posture, which includes at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold. The preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

[0011] In a second aspect, an embodiment of the present application provides a loader trajectory generation device, the device comprising:

[0012] An acquisition module, used for acquiring an initial posture and a terminal posture of the loader, wherein the initial posture and the terminal posture include position coordinates and direction angles;

[0013] A processing module, used to establish a two-dimensional coordinate system with the initial posture as the origin, and determine the target posture of the end posture in the two-dimensional coordinate system;

[0014] A determination module, configured to make a first ray in the opposite direction of the direction angle in the target posture, and determine an intersection point of the first ray and the X-axis when the first ray intersects the X-axis;

[0015] A control module is used to generate a target driving trajectory between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point, which includes at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold, wherein the preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at a maximum steering angle.

[0016] In a third aspect, an embodiment of the present application provides an electronic device, the electronic device comprising:

[0017] A memory and a processor, wherein the memory and the processor are coupled;

[0018] The memory is used to store one or more computer instructions;

[0019] The processor is used to execute the one or more computer instructions to implement the loader trajectory generation method described in any one of the first aspects above.

[0020] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having one or more computer instructions stored thereon, characterized in that the instruction is executed by a processor to implement the loader trajectory generation method described in any one of the first aspects above.

[0021] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the loader trajectory generation method described in any one of the first aspects above.

[0022] Compared with the prior art, this application has the following advantages:

[0023] The loader trajectory generation method provided in the present application obtains the initial posture and terminal posture of the loader, wherein the initial posture and the terminal posture include position coordinates and direction angles; establishes a two-dimensional coordinate system with the initial posture as the origin, and determines the target posture of the terminal posture in the two-dimensional coordinate system; makes a first ray in the opposite direction of the direction angle in the target posture, and determines the intersection of the first ray and the X-axis when the first ray intersects with the X-axis. According to the size of the X-axis coordinate of the intersection, a target driving trajectory containing at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture, and the preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

[0024] Compared with the prior art, the present application takes into account that the loader has a special hinge structure and is related to the vehicle's own performance, resulting in its maximum steering angle being limited, and the traditional trajectory generation method cannot meet these requirements well. After comparison, it is found that the double clothoid curve has good curvature continuity, and only the double clothoid curve needs to be subjected to curvature modification, so that the double clothoid curve based on the curvature modification can be consistent with the loader application scenario, and can be well adapted to the loader's working scenario requirements. Therefore, in the present application, the loader driving trajectory is generated based on the double clothoid curve under curvature restriction, which can ensure that the driving trajectory has good curvature continuity and the maximum curvature is less than or equal to the preset curvature threshold of the turning trajectory when the loader turns at the maximum steering angle, so that the hinge structure can be avoided from being damaged due to the loader turning at a turning angle exceeding the maximum steering angle, and the risk of the vehicle losing control or overturning due to excessive lateral force when turning can be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0026] Figure 1 A schematic diagram of a flow chart of a loader trajectory generation method provided in one embodiment of the present application;

[0027] Figure 2 A schematic diagram of the intersection of a first ray and an X-axis provided in one embodiment of the present application;

[0028] Figure 3 A schematic diagram of the curvature of a double clothoid curve provided in one embodiment of the present application;

[0029] Figure 4 One of the schematic diagrams of the generated loader trajectory provided by one of the embodiments of the present application;

[0030] Figure 5 A second schematic diagram of a generated loader trajectory provided in one embodiment of the present application;

[0031] Figure 6 One of the schematic diagrams of determining a first intermediate posture provided in one embodiment of the present application;

[0032] Figure 7 A second schematic diagram of determining a first intermediate posture according to one embodiment of the present application;

[0033] Figure 8 A third schematic diagram of a generated loader trajectory provided in one embodiment of the present application;

[0034] Fig. 9 A schematic diagram of the structure of a loader trajectory generating device provided in one embodiment of the present application;

[0035] Fig.10 A schematic diagram of the hardware structure of an electronic device provided in one embodiment of the present application.

[0036] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0037] In order to make the purpose, advantages and features of the present application clearer, the present application is described clearly and completely below in conjunction with the accompanying drawings and specific embodiments. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments, and all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0038] It should be noted that, in the description of the present application, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance, and a specific order or sequence. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific circumstances. In addition, in the description of the present application, unless otherwise specified, the term "multiple" refers to two or more. The term "and / or" describes the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can be represented: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are an "or" relationship. The terms "include" and "have" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0039] In order to facilitate understanding of the technical solution of the present application, the relevant concepts involved in the present application are first introduced.

[0040] A loader is a kind of engineering machinery used for material handling and loading, usually used in construction sites, mines, ports, railways and other fields. It has the characteristics of good mobility, high loading efficiency and easy operation, and is often used to load heavy objects such as earthwork materials, coal, ore, etc. Automated loaders can complete operations autonomously without human intervention, thereby improving loading efficiency and operating efficiency. In the operation process of unmanned loaders, mobile navigation occupies the vast majority, so the generation of loader driving trajectories required for navigation is also the most basic and critical part of the operation of unmanned loaders.

[0041] Below, the prior art involved in this application and the problems existing in the prior art are described:

[0042] In the related art, an offline deployment method based on a straight line, an arc line, a Bezier curve, a spline curve, etc. is usually adopted to generate a driving trajectory, and the unmanned loader travels along the generated driving trajectory.

[0043] However, the above-mentioned related technologies still have the following problems: the unique hinge structure of the wheel loader requires the loader's driving trajectory to be as smooth as possible to avoid the risk of turning too fast and deviating from the trajectory and losing control or even overturning, but this results in a certain limit on the maximum steering angle of the loader. The curvature of the loader's driving trajectory generated by the above-mentioned related technologies may exceed the curvature of the turning trajectory when the loader turns at the maximum steering angle, so the above-mentioned driving trajectory has a great driving safety hazard.

[0044] In order to solve the above problems, the present application provides a loader trajectory generation method, a loader trajectory generation device corresponding to the method, an electronic device that can implement the loader trajectory generation method, and a computer-readable storage medium. The following provides embodiments to describe the above method, device, electronic device, and computer-readable storage medium in detail.

[0045] In order to make the purpose and technical solution of the present application clearer and more intuitive, the method provided by the embodiment of the present application will be described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. It is understood that the following embodiments may exist separately, and the following embodiments and features in the embodiments may be combined with each other when there is no conflict between the embodiments provided in the present application, and the same or similar content will not be repeated in different embodiments. In addition, the step sequence in the following method embodiments is only an example, not a strict limitation, and in some cases, the steps shown or described may be performed in a different order from this.

[0046] The present application provides a loader trajectory generation method, device, electronic device and computer-readable storage medium. Specifically, the loader trajectory generation method of one embodiment of the present application can be executed by a computer device, wherein the computer device can be a terminal or a server. The terminal can be a terminal device such as a smart phone, a tablet computer, a laptop computer, a touch screen, etc. The terminal can also include a client, which can be a game application client, a browser client carrying a game program, or an instant messaging client. The server can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, and basic cloud computing services such as big data and artificial intelligence platforms.

[0047] Next, combine Figure 1 , a loader trajectory generation method provided in one embodiment of the present application is described. Figure 1 A schematic flow chart of a loader trajectory generation method provided in one embodiment of the present application.

[0048] like Figure 1 As shown, the loader trajectory generation method includes steps S10-S40:

[0049] S10, obtaining an initial position and a terminal position of the loader, wherein the initial position and the terminal position include position coordinates and direction angles.

[0050] S20, establishing a two-dimensional coordinate system with the initial posture as the origin, and determining the target posture of the end posture in the two-dimensional coordinate system, where the two-dimensional coordinate system includes an X-axis, a Y-axis and a direction angle.

[0051] S30, make a first ray in the opposite direction of the direction angle in the target posture, and when the first ray intersects the X-axis, determine the intersection point of the first ray and the X-axis.

[0052] S40. Based on the size of the X-axis coordinate of the intersection point, a target driving trajectory including at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture. The preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

[0053] The above steps S10-S40 are described in detail below:

[0054] In the embodiment of the present application, the position information of the loader in the material site includes the specific position coordinates (x, y) of the loader in the material site coordinate system, and the direction angle θ of the loader. Among them, the specific position coordinates (x, y) of the loader in the material site coordinate system are usually referenced to the origin of the material site coordinate system. The direction angle of the loader is the direction in which the loader is facing, usually based on due north, and is expressed by the angle θ.

[0055] As mentioned above, the initial position refers to the position and direction of the loader in the material site at the beginning of the task, and the terminal position refers to the position and direction of the loader in the material site when the loader completes the task. For example, the initial position of the loader is (x, y, θ), and the terminal position is (x', y', θ'). When the loader performs the task, the loader needs to start driving from the initial position (x, y, θ), and the destination of the driving is the terminal position (x', y', θ').

[0056] In the embodiment of the present application, a two-dimensional coordinate system is established with the initial posture of the loader as the origin. Among them, the X-axis and Y-axis in the two-dimensional coordinate system define the position relationship in the horizontal and vertical directions respectively, and the origin (0,0) of the two-dimensional coordinate system represents the initial posture of the loader. Usually, the X-axis can be defined as the direction from left to right, and the Y-axis is defined as the direction from bottom to top, but this depends on the specific settings and is sometimes adjusted according to actual conditions.

[0057] The heading angle is usually measured clockwise (or counterclockwise, depending on convention) from the north. For example, if the loader is facing due north at the beginning, the heading angle is 0°. If it is facing due east, the heading angle is 90°. Since the heading angle is not affected by the coordinate system transformation, the origin position corresponding to the initial position in the transformed two-dimensional coordinate system is (0,0,θ).

[0058] Next, to determine the new position of the loader's terminal posture in the two-dimensional coordinate system, that is, the target posture, it is necessary to calculate the coordinate difference between the terminal posture in the terminal posture and the initial posture in the initial posture, that is, including the difference in the X-axis direction and the difference in the Y-axis direction, that is, the target posture of the loader's terminal posture in the two-dimensional coordinate system is (x'-x, y'-y, θ'). In this way, the conversion from the original coordinate system to the new two-dimensional coordinate system is completed, and the posture information of the loader's initial posture and terminal posture in the two-dimensional coordinate system is clarified.

[0059] Exemplarily, the initial posture of the loader is (20, 50, 20°), the final posture is (100, 150, 150°), a two-dimensional coordinate system is established with the initial posture (20, 50, 20°) as the origin, and the target posture of the final posture in the two-dimensional coordinate system is (100-20, 150-50, 150°) = (80, 100, 150°).

[0060] In the embodiment of the present application, a first ray is made in the opposite direction of the direction angle in the target posture, and when the first ray intersects the X-axis, the intersection point (x m ,0).

[0061] Next, combine Figure 2 , make a first ray in the opposite direction of the target position and orientation angle, and explain the following three situations when the first ray intersects with the X-axis and there is an intersection point, and the X-axis coordinate of the intersection point is greater than zero, equal to zero, and less than zero. Figure 2 A schematic diagram of the intersection of a first ray and an X-axis provided in one embodiment of the present application.

[0062] like Figure 2 Shown, including Figure 2 (a) Figure 2 (b) and Figure 2 (c). Figure 2 As shown in (a), in the two-dimensional coordinate system, the initial position is the origin position, the origin position is (0,0,0°), and the target position is (25,20,35°). The first ray is made in the opposite direction of the direction angle 35° in the target position. There is an intersection point where the first ray intersects the X-axis. The X-axis coordinate of the intersection point is x m Greater than zero. Figure 2 As shown in (b), in the two-dimensional coordinate system, the origin position is (0,0,0°) and the target position is (25,20,45°). A first ray is drawn in the opposite direction of the target position with a direction angle of 45°. There is an intersection point where the first ray intersects the X-axis. The X-axis coordinate of the intersection point is x m is equal to zero. Figure 2As shown in (c), in the two-dimensional coordinate system, the origin position is (0, 0, 0°) and the target position is (25, 20, 75°). The first ray is drawn in the opposite direction of the 75° direction angle in the target position. There is an intersection point where the first ray intersects the X-axis. The X-axis coordinate of the intersection point is x m Less than zero.

[0063] In the embodiment of the present application, based on the fact that the double clothoid curve has good curvature continuity, but there is no maximum curvature limit in the double clothoid curve, the maximum curvature limit is imposed on the double clothoid curve to generate a loader driving trajectory that meets the maximum steering angle of the loader. The driving trajectory generated in this way can ensure that the limit on the maximum steering angle of the loader is met.

[0064] Next, the clothoid curve is introduced.

[0065] The curvature of a clothoid curve is proportional to the length of the curve, as shown in Formula 1:

[0066] Cv(s)=ks+Cv0Formula 1

[0067] Where s is the length of the clothoid curve, Cv(s) is the curvature of the clothoid curve, and k is the coefficient of the curve sharpness, that is, the rate of change of the curvature of the clothoid curve.

[0068] The integral of the curvature over the length of the curve is the direction of the tangent vector θ of the curve (i.e. the direction indicated by the direction angle), as shown in Formula 2:

[0069]

[0070] Among them, θ0 is the initial direction of the clothoid curve. When the initial posture of the loader is known, the posture of the loader at time t is shown in Formula 3:

[0071] x f (t) = x f0 +∫v f (t)cosθ f (t)dt

[0072] y f (t) = y f0 +∫v f (t)sinθ f (t)dt

[0073]

[0074] Among them, x f0 ,y f0 ,θ f0 is the initial value, then the coordinates of the clothoid curve can be calculated according to the length of the clothoid curve, as shown in Formula 4:

[0075]

[0076] For ease of calculation, the initial value Cv0,x f0 ,y f0 ,θ f0 The value of is set to zero. Therefore, the coordinates of the clothoid curve can be calculated by the tangent vector θ of the curve, as shown in Formula 5:

[0077]

[0078] The integral term on the right side of the equal sign in the above formula 5 is called the Fresnel integral. Expand the integral term in the above formula 5 to a series term, comprehensively consider the curve accuracy and calculation complexity, take the first 3 terms, and the formula 5 can be simplified to the formula 6:

[0079]

[0080] As mentioned above, Formula 6 is the basic formula for generating a clothoid curve. Therefore, by combining Formula 2 and Formula 6, a clothoid curve can be generated between two postures.

[0081] Among them, the clothoid curve has the following two geometric relationships:

[0082] Geometric relationship 1. When the target direction, that is, the curve tangent vector θ is fixed, the target point (x, y) is on a straight line passing through the origin with a slope of K. The smaller the curve sharpness k, the slower the curvature of the clothoid curve changes, and the farther the target point (x, y) is from the starting point, the value of the slope K can be referred to as shown in Formula 7:

[0083]

[0084] Geometric relationship 2. When generating a double clothoid curve, let the tangent direction of the maximum curvature point be θ', and the relationship exists as shown in Formula 8:

[0085] θ=2θ'

[0086]

[0087] The difference between a clothoid and a double clothoid is that the initial curvature of a clothoid is 0 by default, and the final curvature is the largest. However, the initial and final curvatures of a double clothoid are both 0. A double clothoid is a curve obtained by performing reverse symmetry processing on two clothoid curves (i.e. single clothoid curves) and then splicing them.

[0088] In the embodiment of the present application, a first ray is made in the opposite direction of the direction angle in the target posture. When the first ray intersects the X-axis, the size of the X-axis coordinate of the intersection point includes three situations: greater than zero, less than zero, and equal to zero. The following describes the corresponding geometric relationships and requirements for the driving trajectory for each of the three situations.

[0089] When the X-axis coordinate of the intersection point is greater than zero, a driving trajectory that meets the curvature requirement can be generated using only one section of double clothoid curve, without using multiple sections of double clothoid curves.

[0090] When the X-axis coordinate of the intersection is less than zero, the driving trajectory from the direction angle of the initial posture to the direction angle of the terminal posture must be retreated a certain distance based on the direction angle of the initial posture to have enough space to generate a driving trajectory that meets the curvature requirements. However, since the loader is not allowed to travel backward, it can only be segmented between the initial posture and the terminal posture, and two segments are sufficient, that is, two double clothoid curves are generated from the initial posture to the terminal posture, and the two double clothoid curves are spliced ​​to obtain a driving trajectory that meets the curvature requirements.

[0091] When the X-axis coordinate of the intersection point is equal to zero, since this situation rarely occurs and is a critical situation between the above two situations, a special processing method is used, and the specific processing method is described in detail later.

[0092] For the three cases of the size of the X-axis coordinate of the intersection point, a target driving trajectory containing at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture. The preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

[0093] The loader trajectory generation method provided in the embodiment of the present application obtains the initial posture and terminal posture of the loader, wherein the initial posture and terminal posture include position coordinates and direction angles. A two-dimensional coordinate system is established with the initial posture as the origin, and the target posture of the terminal posture in the two-dimensional coordinate system is determined. A first ray is made in the opposite direction of the direction angle in the target posture, and when the first ray intersects with the X-axis, the intersection point of the first ray and the X-axis is determined. According to the size of the X-axis coordinate of the intersection point, a target driving trajectory containing at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture, and the preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

[0094] Compared with the prior art, the present application takes into account that the loader has a special hinge structure and is related to the vehicle's own performance, resulting in its maximum steering angle being limited, and the traditional trajectory generation method cannot meet these requirements well. After comparison, it is found that the double clothoid curve has good curvature continuity, and only the double clothoid curve needs to be subjected to curvature modification, so that the double clothoid curve based on the curvature modification can be consistent with the loader application scenario, and can be well adapted to the loader's working scenario requirements. Therefore, in the present application, the loader driving trajectory is generated based on the double clothoid curve under curvature restriction, which can ensure that the driving trajectory has good curvature continuity and the maximum curvature is less than or equal to the preset curvature threshold of the turning trajectory when the loader turns at the maximum steering angle, so that the hinge structure can be avoided from being damaged due to the loader turning at a turning angle exceeding the maximum steering angle, and the risk of the vehicle losing control or overturning due to excessive lateral force when turning can be prevented.

[0095] Based on the above embodiments, the loader trajectory generation method provided in the embodiments of the present application is further described below.

[0096] In an optional implementation manner, a possible implementation manner of step S40 "generating a target driving trajectory including at least one double clothoid curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point" includes step S401:

[0097] S401. When the X-axis coordinate of the intersection point is greater than zero, a double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture as the target driving trajectory. The preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

[0098] In an embodiment of the present application, a double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is constructed with the initial posture of the two-dimensional coordinate system as the starting point and the target posture as the end point, and the double clothoid curve connecting the initial posture and the target posture is used as the target driving trajectory.

[0099] Next, combine Figure 3 , the curvature characteristics of the double clothoid curve are explained. Figure 3 A schematic diagram of the curvature of a double clothoid curve provided in one embodiment of the present application.

[0100] like Figure 3 As shown, it includes a two-dimensional coordinate system 1 and a two-dimensional coordinate system 2, wherein the two-dimensional coordinate system 1 illustrates two double clothoid curves of different lengths (i.e., curve 1 and curve 2), wherein the origin positions of the double clothoid curve 1 and the double clothoid curve 2 are both (0,0,0), and the target positions of the double clothoid curve 1 and the double clothoid curve 2 are (x1,y1,θ), (x i ,yi ,θ). The corresponding relationship between the curve length and the curve curvature of the double clothoid curve 1 and the double clothoid curve 2 is shown in the two-dimensional coordinate system 2. When the target direction θ is given, the maximum curvature Cv of the double clothoid curve segment max It is always at the midpoint of the curve and corresponds one-to-one with the sharpness k of the curve, such as Figure 3 As shown, the maximum curvature Cv of the double clothoid curve 1 is max1 Always at the midpoint 1 of the curve, and one-to-one correspondence with the curve sharpness k1; the maximum curvature Cv of the double clothoid curve 2 maxi Always at the midpoint 2 of the curve, and with the sharpness k of the curve i One to one correspondence. Figure 3 As shown in the figure, when the sharpness k of the double clothoid curve decreases continuously (such as k i ≤k1), the slope of the curvature curve decreases continuously, and the maximum curvature of the curve also decreases continuously (such as Cv maxi ≤Cv max1 ), when the curve sharpness k decreases until the maximum curvature Cv of the curve max When it is equal to the preset curvature threshold, record the current maximum curve sharpness k max Therefore, the orientation angle θ and the maximum curve sharpness k of the target pose can be generated offline max The corresponding table can be referred to Table 1. When generating the loader driving trajectory online, it is only necessary to ensure that k ≤ k max That's it.

[0101] Table 1

[0102] The direction of the target pose θ Maximum curve sharpness <![CDATA[θ1]]> <![CDATA[k max11 ]]> <![CDATA[θ2]]> <![CDATA[k max22 ]]> <![CDATA[θ3]]> <![CDATA[k max33 ]]> … …

[0103] As shown in Table 1, when the orientation angle of the target posture is θ1, the maximum curve sharpness of the double clothoid curve is k max11 When the orientation angle of the target pose is θ2, the maximum curve sharpness of the double clothoid curve is k max22 When the orientation angle of the target pose is θ3, the maximum curve sharpness of the curve is k max33 .

[0104] In a possible implementation, since the curvatures at both ends of the hyperbolic clothoid are both 0, one or more line segments can be added at both ends to ensure the curvature continuity, so as to ensure that the loader can smoothly transition between the straight line segment and the hyperbolic clothoid. Specifically, a line segment is added at both ends of the initial posture and the target posture, so that one or more straight line segments at both ends are connected with the hyperbolic clothoid in the middle to form a complete driving trajectory (i.e., straight lines at both ends and a hyperbolic clothoid in the middle). The key to splicing is to ensure that the loader can smoothly transition between the various segments in the driving trajectory, thereby avoiding discomfort or safety issues caused by sudden changes in curvature.

[0105] Next, combine Figure 4 , an exemplary explanation is given for “when the X-axis coordinate of the intersection point is greater than zero, a double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture as the target driving trajectory”, Figure 4 One of the schematic diagrams of the generated loader trajectory provided in one embodiment of the present application.

[0106] like Figure 4 As shown, the first ray is drawn in the opposite direction of the target position and the X-axis coordinate x of the intersection point where the first ray intersects the X-axis is m When θ is greater than zero, a double clothoid curve T11 with a maximum curvature less than or equal to a preset curvature threshold is generated between the origin posture (0,0,0) with the initial posture as the origin and the target posture (x,y,θ) as the driving trajectory of the loader.

[0107] In an optional implementation manner, another possible implementation manner of step S40 "generating a target driving trajectory including at least one double clothoid curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point" includes step S402:

[0108] S402: When the X-axis coordinate of the intersection point is less than zero, a target driving trajectory formed by connecting two double clothoid curves whose maximum curvature is less than or equal to a preset curvature threshold is generated between the initial posture and the target posture.

[0109] In an optional implementation manner, a possible implementation manner of step S402 includes steps S4021-S4024:

[0110] S4021: When the X-axis coordinate of the intersection point is less than zero, determine a first intermediate posture between the initial posture and the target posture, wherein the curvatures of the first intermediate posture to the initial posture and the target posture are both less than or equal to a preset curvature threshold.

[0111] S4022: Generate a first biclotic curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the first intermediate posture according to the initial posture and the first intermediate posture.

[0112] S4023. Generate, according to the first intermediate posture and the target posture, a second biclotic curve having a maximum curvature less than or equal to a preset curvature threshold between the first intermediate posture and the target posture.

[0113] S4024: Splice the first double clothoid curve and the second double clothoid curve to obtain a target driving trajectory.

[0114] Next, combine Figure 5, an exemplary explanation is given for “when the X-axis coordinate of the intersection point is less than zero, generating a double clothoid curve including at least one maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture as the target driving trajectory”, Figure 5 The second schematic diagram of the generated loader trajectory provided in one embodiment of the present application.

[0115] like Figure 5 As shown in FIG. 1 , a first intermediate pose (x , y , θ ) is determined between the origin pose (0, 0, 0) of the two-dimensional coordinate system established with the initial pose as the origin and the target pose (x, y, θ). t ,y t ,θ t ), at the origin pose (0,0,0) with the initial pose as the origin and the first intermediate pose (x t ,y t ,θ t ) generates a first double clothoid curve T22 with a maximum curvature less than or equal to a preset curvature threshold, and in the first intermediate posture (x t ,y t ,θ t ) and the target posture (x, y, θ) generate a second double clothoid curve T33 with a maximum curvature less than or equal to a preset curvature threshold, and the first double clothoid curve T22 and the second double clothoid curve T22 are spliced ​​to obtain the target driving trajectory.

[0116] In an embodiment of the present application, when the X-axis coordinate of the intersection is less than zero, a first intermediate posture is determined between the initial posture and the target posture. A first double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the first intermediate posture. A second double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the first intermediate posture and the target posture. The first double clothoid curve and the second double clothoid curve are spliced ​​to obtain a target driving trajectory. By inserting the first intermediate posture between the initial posture and the target posture and generating a double clothoid curve, it can be ensured that the transition from the straight segment to the curved segment is smoother. This smooth transition can reduce the impact and vibration of the vehicle when turning, and improve the stability and comfort of driving. And, by setting the first intermediate posture, it is ensured that the curvature from the initial posture to the first intermediate posture, and from the first intermediate posture to the target posture is less than or equal to the preset curvature threshold. This can ensure that the maximum curvature will not exceed the maximum steering capacity of the vehicle throughout the path, thereby avoiding the risk of loss of control due to oversteering.

[0117] In an optional implementation manner, a possible implementation manner of "determining a first intermediate posture between the initial posture and the target posture" in step S4021 includes steps S40211-S40215:

[0118] S40211. Move along the direction perpendicular to the X-axis of the target posture to obtain at least one first posture.

[0119] S40212. Determine a plurality of second poses on a line connecting the first pose and the origin.

[0120] S40213. For each second posture, take the second posture as the starting point and make a second ray along the direction indicated by the direction angle in the second posture.

[0121] S40214. Determine the second ray that intersects the first ray as the target second ray.

[0122] S40215. When the curve sharpness corresponding to the direction angle in the second posture corresponding to the second ray of the target is less than or equal to a preset curve sharpness threshold, determine the second posture corresponding to the second ray of the target as the first intermediate posture.

[0123] Next, combine Figure 6 and Figure 7 , an exemplary method of determining the first intermediate posture is described, Figure 6 One of the schematic diagrams for determining the first intermediate posture provided in one embodiment of the present application, Figure 7 The second schematic diagram of determining the first intermediate posture provided in one embodiment of the present application.

[0124] like Figure 6 As shown in the figure, the target pose (x, y, θ) is moved closer to the x-axis to obtain multiple poses (x, y i ,θ),y i ∈(0,y), the origin position (0,0,0) and each position (x,y i ,θ),y i ∈(0,y) on the line segment connecting multiple second poses (x t ,y t ,θ i ), find a suitable second posture as the first intermediate posture in the multiple second postures. Under this restriction, the geometric relationship is shown in Formula 9:

[0125]

[0126] By the aforementioned Figure 3 From the content, we can see that from the origin pose to the second pose (x t ,y t ,θ i ) to generate the driving trajectory, it is only necessary to ensure that the curve sharpness of the driving trajectory k≤k max That’s it, here we can choose k=k max , the coordinates (x t ,y t).

[0127] Therefore, the key issue here is to determine the second pose (x t ,y t ,θ i ) to the target pose (x, y, θ) to generate a path that meets the curvature requirement. t ,y t ) is the starting point, θ i The second ray is made in the positive direction, starting from (x, y), and the first ray is made in the reverse direction. When the second ray and the first ray intersect, the second position (x t ,y t ,θ i ) to the target position (x, y, θ) to generate a driving trajectory to meet the curvature requirement, just ensure that k ≤ k max That is, there will be an intersection with the first ray and satisfy k≤k max The second ray of the target is determined as the target second ray. The second posture corresponding to the target second ray is determined as the first intermediate posture.

[0128] like Figure 7 As shown, when (x t1 ,y t1 ) is the starting point, θ i The second ray is made in the positive direction, starting from (x, y), and the first ray is made in the reverse direction. Since there is no intersection between the second ray and the first ray, the second posture (x t1 ,y t1 ,θ i ) does not meet the requirements and cannot be used as the second target ray. The second pose (x t2 ,y t2 ,θ i ) Since k≤k is not satisfied max , so the second pose (x t2 ,y t2 ,θ i ). The second pose (x tm ,y tm ,θ i ) satisfies the above requirement k≤k max , so the second posture (x tm ,y tm ,θ i ) as the first intermediate posture.

[0129] In an optional implementation manner, another possible implementation manner of step S40 "generating a target driving trajectory including at least one double clothoid curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point" includes steps S4031-S4035:

[0130] S4031. When the X-axis coordinate of the intersection point is equal to zero, determine a third posture, the X-axis coordinate in the third posture is a value range of the X-axis coordinate in the target posture that is greater than zero and less than half of the X-axis coordinate in the target posture, the Y-axis coordinate in the third posture is 0, and the direction angle in the third posture is zero.

[0131] In the above, the X-axis coordinate in the third posture is greater than zero and less than half of the X-axis coordinate in the target posture. Preferably, the X-axis coordinate in the third posture is one third of the X-axis coordinate in the target posture.

[0132] S4032. Connect the initial posture and the third posture through a straight line to obtain a first line segment.

[0133] S4033: Determine a second intermediate posture between the third posture and the target posture, wherein the curvatures of the second intermediate posture to the third posture and the target posture are both less than or equal to a preset curvature threshold.

[0134] S4034. Generate a third biclotic curve between the third posture and the second intermediate posture according to the third posture and the second intermediate posture, the third biclotic curve having a maximum curvature less than or equal to a preset curvature threshold.

[0135] S4035. Generate a fourth biclotic curve having a maximum curvature less than or equal to a preset curvature threshold between the second intermediate posture and the target posture according to the second intermediate posture and the target posture.

[0136] S4036: splice the third double clothoid curve and the fourth double clothoid curve to obtain a target driving trajectory.

[0137] In an embodiment of the present application, when the X-axis coordinate of the intersection is equal to zero, a third posture is determined, the X-axis coordinate in the third posture is a value range of the X-axis coordinate in the target posture greater than zero and less than half of the X-axis coordinate in the target posture, the Y-axis coordinate in the third posture is 0, and the direction angle in the third posture is zero. A second intermediate posture is determined between the third posture and the target posture. A third double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the third posture and the second intermediate posture. A fourth double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the second intermediate posture and the target posture. The third double clothoid curve and the fourth double clothoid curve are spliced ​​to obtain a target driving trajectory. By inserting the second intermediate posture between the third posture and the target posture and generating a double clothoid curve, a smoother transition from a straight segment to a curved segment can be ensured. This smooth transition can reduce the impact and vibration of the vehicle when turning, and improve the stability and comfort of driving. Furthermore, by setting the second intermediate posture, it is ensured that the curvature from the third posture to the second intermediate posture and from the second intermediate posture to the target posture is less than or equal to the preset curvature threshold. This ensures that the maximum curvature in the entire path will not exceed the maximum steering capacity of the vehicle, thereby avoiding the risk of loss of control due to oversteering.

[0138] In an optional implementation manner, the loader trajectory generation method provided in the embodiment of the present application further includes step S50:

[0139] S50: When the first ray coincides with the X-axis, the initial posture and the target posture are connected by a straight line to obtain a target driving trajectory.

[0140] In an optional implementation manner, the loader trajectory generation method provided in the embodiment of the present application further includes steps S601-S604:

[0141] S601: When the first ray does not intersect the X-axis, the midpoint of the line connecting the initial posture and the target posture is taken as the third intermediate posture.

[0142] S602: Generate a fifth biclotic curve between the initial posture and the third intermediate posture, the fifth biclotic curve having a maximum curvature less than or equal to a preset curvature threshold.

[0143] S603: Generate a sixth biclotic curve between the third intermediate posture and the target posture, the sixth biclotic curve having a maximum curvature less than or equal to a preset curvature threshold, according to the third intermediate posture and the target posture.

[0144] S604: splice the fifth double clothoid curve and the sixth double clothoid curve to obtain a target driving trajectory.

[0145] The implementation of the above steps S602-S604 can refer to the implementation of the relevant steps in S402, which will not be repeated here.

[0146] Next, combine Figure 8 , an exemplary description is given of the loader trajectory generated by the loader trajectory generation method provided by the present application, Figure 8 The third schematic diagram of the generated loader trajectory provided in one embodiment of the present application.

[0147] like Figure 8 Shown, including Figure 8 (a) and Figure 8 (b) If Figure 8 As shown in (a), there are four postures including POS1, POS2, POS3 and POS4. POS1 is taken as the initial posture and POS2 is taken as the terminal posture. A two-dimensional coordinate system is established with the initial posture POS1 as the origin, and the target posture of the terminal posture POS2 in the two-dimensional coordinate system is determined. A first ray is made in the opposite direction of the direction angle in the target posture. The X-axis coordinate of the intersection of the first ray L1 and the X-axis is equal to 0, and a loader trajectory T12 is generated between POS1 and POS2. POS2 is taken as the initial posture and POS3 is taken as the terminal posture. A two-dimensional coordinate system is established with the initial posture POS2 as the origin, and the target posture of the terminal posture POS3 in the two-dimensional coordinate system is determined. A first ray L2 is made in the opposite direction of the direction angle in the target posture. The X-axis coordinate of the intersection of the first ray L2 and the X-axis is less than 0, and a loader trajectory T23 is generated between POS2 and POS3. Take POS3 as the initial posture and POS4 as the terminal posture, establish a two-dimensional coordinate system with the initial posture POS3 as the origin, determine the target posture of the terminal posture POS4 in the two-dimensional coordinate system, and make the first ray L3 in the opposite direction of the direction angle in the target posture. The X-axis coordinate of the intersection of the first ray L3 and the X-axis is greater than 0, and a loader trajectory T34 is generated between POS3 and POS4.

[0148] In this application, by modifying the double clothoid curve, the double clothoid curve is used to generate a loader driving trajectory between the initial position and the terminal position of the loader under curvature restriction. Such a driving trajectory can be well adapted to the working scene requirements of the loader. At the same time, using the double clothoid curve, such as Figure 8 As shown in (b), the initial curvatures of the generated loader driving trajectories T11, T12, and T13 are all kept at 0 (that is, the trajectory curvatures corresponding to the four postures POS1, POS2, POS3, and POS4 are all 0), that is, the initial steering angle of the loader in each trajectory is 0, which meets the safety requirements of the loader shoveling and unloading.

[0149] The loader trajectory generation device provided in the present application is described below. The loader trajectory generation device described below and the loader trajectory generation method described above can be referenced to each other.

[0150] Fig. 9 This is a schematic diagram of the structure of a loader trajectory generation device provided in one embodiment of the present application. Fig. 9 As shown, the loader trajectory generating device 900 includes: an acquisition module 901 , a processing module 902 , a determination module 903 and a control module 904 .

[0151] An acquisition module, used for acquiring an initial posture and a terminal posture of the loader, wherein the initial posture and the terminal posture include position coordinates and direction angles;

[0152] A processing module, used to establish a two-dimensional coordinate system with the initial posture as the origin, and determine the target posture of the end posture in the two-dimensional coordinate system;

[0153] A determination module, configured to make a first ray in the opposite direction of the direction angle in the target posture, and determine an intersection point of the first ray and the X-axis when the first ray intersects the X-axis;

[0154] A control module is used to generate a target driving trajectory between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point, which includes at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold, wherein the preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at a maximum steering angle.

[0155] In an optional implementation manner, the control module is specifically used to:

[0156] When the X-axis coordinate of the intersection point is greater than zero, a double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture as a target driving trajectory.

[0157] In an optional implementation manner, the control module is specifically used to:

[0158] When the X-axis coordinate of the intersection point is less than zero, a target driving trajectory formed by splicing two double clothoid curves whose maximum curvature is less than or equal to the preset curvature threshold is generated between the initial posture and the target posture.

[0159] In an optional implementation manner, the control module is specifically used to:

[0160] When the X-axis coordinate of the intersection point is less than zero, a first intermediate posture is determined between the initial posture and the target posture; wherein the curvatures of the first intermediate posture to the initial posture and the target posture are both less than or equal to the preset curvature threshold;

[0161] According to the initial posture and the first intermediate posture, generating a first double clothoid curve with a maximum curvature less than or equal to the preset curvature threshold between the initial posture and the first intermediate posture;

[0162] According to the first intermediate posture and the target posture, generating a second double clothoid curve between the first intermediate posture and the target posture, the second double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold;

[0163] The first double clothoid curve and the second double clothoid curve are spliced ​​to obtain a target driving trajectory.

[0164] In an optional implementation manner, the control module is specifically used to:

[0165] Move along the direction perpendicular to the X-axis of the target posture to obtain at least one first posture;

[0166] Determining a plurality of second postures on a line connecting the first posture and the origin;

[0167] For each of the second postures, taking the second posture as a starting point, a second ray is drawn along the direction indicated by the direction angle in the second posture;

[0168] Determine a second ray that intersects the first ray as a target second ray;

[0169] When the curve sharpness corresponding to the direction angle in the second posture corresponding to the second ray of the target is less than or equal to a preset curve sharpness threshold, the second posture corresponding to the second ray of the target is determined as the first intermediate posture.

[0170] In an optional implementation manner, the control module is further used for:

[0171] When the X-axis coordinate of the intersection point is equal to zero, a third posture is determined, wherein the X-axis coordinate in the third posture is a value range of the X-axis coordinate in the target posture that is greater than zero and less than half of the X-axis coordinate in the target posture, the Y-axis coordinate in the third posture is 0, and the direction angle in the third posture is zero degrees;

[0172] Connecting the initial posture and the third posture through a straight line to obtain a first line segment;

[0173] Determining a second intermediate posture between the third posture and the target posture; wherein the curvatures of the second intermediate posture to the third posture and the target posture, respectively, are both less than or equal to the preset curvature threshold;

[0174] According to the third posture and the second intermediate posture, generating a third double clothoid curve between the third posture and the second intermediate posture, the third double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold;

[0175] According to the second intermediate posture and the target posture, generating a fourth double clothoid curve between the second intermediate posture and the target posture, the fourth double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold;

[0176] The third double clothoid curve and the fourth double clothoid curve are spliced ​​to obtain a target driving trajectory.

[0177] In an optional implementation manner, the control module is further used for:

[0178] When the first ray coincides with the X-axis, the initial posture and the target posture are connected by a straight line to obtain a target driving trajectory.

[0179] In an optional implementation manner, the control module is further used for:

[0180] In the case where the first ray does not intersect the X-axis, taking the midpoint of the line connecting the initial posture and the target posture as the third intermediate posture;

[0181] generating a fifth double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold between the initial posture and the third intermediate posture;

[0182] According to the third intermediate posture and the target posture, generating a sixth double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold between the third intermediate posture and the target posture;

[0183] The fifth double clothoid curve and the sixth double clothoid curve are spliced ​​to obtain a target driving trajectory.

[0184] The loader trajectory generation device provided in this embodiment can be used to execute the technical solution of the above-mentioned loader trajectory generation method embodiment. Its implementation principle and technical effects are similar, and this embodiment will not be repeated here.

[0185] Fig.10 A schematic diagram of the hardware structure of an electronic device provided in one embodiment of the present application is shown in FIG. Fig.10 As shown, the electronic device 1000 of this embodiment includes: a processor 1001 and a memory 1002;

[0186] Memory 1002, used for storing computer-executable instructions;

[0187] The processor 1001 is used to execute the computer-executable instructions stored in the memory to implement the various steps performed by the loader trajectory generation method in the above embodiment. For details, please refer to the relevant description in the above method embodiment.

[0188] Optionally, the memory 1002 may be independent or integrated with the processor 1001 .

[0189] When the memory 1002 is independently provided, the electronic device further includes a bus 1003 for connecting the memory 1002 and the processor 1001 .

[0190] One embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions. When a processor executes the computer-executable instructions, the technical solution corresponding to the loader trajectory generation method in any of the above embodiments executed by the above electronic device is implemented.

[0191] One embodiment of the present application further provides a computer program product, the program product comprising: a computer program, the computer program is stored in a readable storage medium, at least one processor of an electronic device can read the computer program from the readable storage medium, and at least one processor executes the computer program so that the electronic device executes the technical solution corresponding to the loader trajectory generation method in any of the above embodiments.

[0192] Although the present application is disclosed as above in the form of a preferred embodiment, it is not intended to limit the present application. Any technical personnel in this field may make possible changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be based on the scope defined by the claims of the present application.

[0193] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0194] The above-mentioned integrated module implemented in the form of a software function module can be stored in a computer-readable storage medium. The above-mentioned software function module is stored in a storage medium, including a number of instructions for enabling an electronic device (which can be a personal computer, a server, or a network device, etc.) or a processor (English: processor) to perform some steps of the method described in each embodiment of the present application.

[0195] It should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the invention may be directly implemented as being executed by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor.

[0196] The memory may include a high-speed RAM memory, and may also include a non-volatile storage NVM, such as at least one disk memory, and may also be a USB flash drive, a mobile hard disk, a read-only memory, a magnetic disk or an optical disk, etc.

[0197] The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of the present application is not limited to only one bus or one type of bus.

[0198] The above storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The storage medium can be any available medium that can be accessed by a general or special purpose computer.

[0199] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0200] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A loader trajectory generation method, characterized in that: The method comprises: Acquire an initial position and a terminal position of the loader, wherein the initial position and the terminal position include position coordinates and direction angles; Establishing a two-dimensional coordinate system with the initial posture as the origin, and determining the target posture of the end posture in the two-dimensional coordinate system; Make a first ray in the opposite direction of the direction angle in the target posture, and when the first ray intersects the X-axis, determine the intersection point of the first ray and the X-axis; According to the size of the X-axis coordinate of the intersection, a target driving trajectory is generated between the initial posture and the target posture, which includes at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold. The preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at the maximum steering angle.

2. The method according to claim 1, characterized in that The step of generating a target driving trajectory including at least one double clothoid curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point comprises: When the X-axis coordinate of the intersection point is greater than zero, a double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold is generated between the initial posture and the target posture as a target driving trajectory.

3. The method according to claim 1, characterized in that: The step of generating a target driving trajectory including at least one double clothoid curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point comprises: When the X-axis coordinate of the intersection point is less than zero, a target driving trajectory formed by splicing two double clothoid curves whose maximum curvature is less than or equal to the preset curvature threshold is generated between the initial posture and the target posture.

4. The method according to claim 3, characterized in that The step of generating a target driving trajectory formed by splicing two double clothoid curves whose maximum curvature is less than or equal to the preset curvature threshold between the initial posture and the target posture comprises: Determine a first intermediate posture between the initial posture and the target posture; wherein the curvatures of the first intermediate posture to the initial posture and the target posture are both less than or equal to the preset curvature threshold; According to the initial posture and the first intermediate posture, generating a first double clothoid curve with a maximum curvature less than or equal to the preset curvature threshold between the initial posture and the first intermediate posture; According to the first intermediate posture and the target posture, generating a second double clothoid curve between the first intermediate posture and the target posture, the second double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold; The first double clothoid curve and the second double clothoid curve are spliced ​​to obtain a target driving trajectory.

5. The method according to claim 4, characterized in that The determining a first intermediate posture between the initial posture and the target posture comprises: Move along the direction perpendicular to the X-axis of the target posture to obtain at least one first posture; Determining a plurality of second postures on a line connecting the first posture and the origin; For each of the second postures, taking the second posture as a starting point, a second ray is drawn along the direction indicated by the direction angle in the second posture; Determine a second ray that intersects the first ray as a target second ray; When the curve sharpness corresponding to the direction angle in the second posture corresponding to the second ray of the target is less than or equal to a preset curve sharpness threshold, the second posture corresponding to the second ray of the target is determined as the first intermediate posture.

6. The method according to claim 1, characterized in that The step of generating a target driving trajectory including at least one double clothoid curve having a maximum curvature less than or equal to a preset curvature threshold between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point comprises: When the X-axis coordinate of the intersection point is equal to zero, a third posture is determined, wherein the value range of the X-axis coordinate in the third posture is greater than zero and less than half of the X-axis coordinate in the target posture, the Y-axis coordinate in the third posture is 0, and the direction angle in the third posture is zero; Connecting the initial posture and the third posture through a straight line to obtain a first line segment; Determining a second intermediate posture between the third posture and the target posture; wherein the curvatures of the second intermediate posture to the third posture and the target posture, respectively, are both less than or equal to the preset curvature threshold; According to the third posture and the second intermediate posture, generating a third double clothoid curve between the third posture and the second intermediate posture, the third double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold; According to the second intermediate posture and the target posture, generating a fourth double clothoid curve between the second intermediate posture and the target posture, the fourth double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold; The third double clothoid curve and the fourth double clothoid curve are spliced ​​to obtain a target driving trajectory.

7. The method according to claim 1, characterized in that The method further comprises: When the first ray coincides with the X-axis, the initial posture and the target posture are connected by a straight line to obtain a target driving trajectory.

8. The method according to claim 1, characterized in that The method further comprises: In the case where the first ray does not intersect the X-axis, taking the midpoint of the line connecting the initial posture and the target posture as the third intermediate posture; generating a fifth double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold between the initial posture and the third intermediate posture; According to the third intermediate posture and the target posture, generating a sixth double clothoid curve having a maximum curvature less than or equal to the preset curvature threshold between the third intermediate posture and the target posture; The fifth double clothoid curve and the sixth double clothoid curve are spliced ​​to obtain a target driving trajectory.

9. A loader trajectory generating device, characterized in that: The device comprises: An acquisition module, used for acquiring an initial posture and a terminal posture of the loader, wherein the initial posture and the terminal posture include position coordinates and direction angles; A processing module, used to establish a two-dimensional coordinate system with the initial posture as the origin, and determine the target posture of the end posture in the two-dimensional coordinate system; A determination module, configured to make a first ray in the opposite direction of the direction angle in the target posture, and determine an intersection point of the first ray and the X-axis when the first ray intersects the X-axis; A control module is used to generate a target driving trajectory between the initial posture and the target posture according to the size of the X-axis coordinate of the intersection point, which includes at least one double clothoid curve with a maximum curvature less than or equal to a preset curvature threshold, wherein the preset curvature threshold refers to the curvature of the turning trajectory when the loader turns at a maximum steering angle.

10. An electronic device, characterized in that: The electronic device comprises: Processor; and The memory is used to store a data processing program. After the electronic device is powered on and the program is run by the processor, the loader trajectory generation method as described in any one of claims 1 to 8 is executed.

11. A computer-readable storage medium, characterized in that: A data processing program is stored, and the program is run by a processor to execute the loader trajectory generation method as described in any one of claims 1-8.

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