Shovel trajectory planning method and device, electronic equipment and loader

Abstract

The application provides a shovel trajectory planning method and device and electronic equipment. The energy consumption of a shovel trajectory is described based on a shovel trajectory model, the minimum energy consumption of the shovel trajectory is taken as an optimization target, a target function of a trajectory generation problem is constructed, a constraint condition is constructed based on a preset bucket full rate threshold, a preset variable threshold and a preset shovel depth, the target function is optimally solved based on the constraint condition, a target shovel trajectory is obtained, the planning of the shovel trajectory is implemented, and thus the shovel efficiency is improved and the shovel energy consumption is reduced.

Description

Technical Field

[0001] This application relates to the field of unmanned loader technology, specifically to a digging trajectory planning method, device, electronic equipment, and loader. Background Technology

[0002] Loaders, as important equipment in the construction machinery industry, are widely used in earthwork and rock excavation operations covering mixing plants, docks, mines, highways, and other scenarios. Their primary task is the transfer of bulk materials such as earth and rock. Currently, loaders are all manually operated. Due to harsh working environments, high work intensity, and the risk of personal injury, unmanned loaders and automated excavation technologies will become the future development trend.

[0003] As a crucial component of autonomous shoveling technology, shoveling trajectory planning is still in its early stages of development. Effective shoveling trajectory planning methods will significantly improve the smoothness, efficiency, fuel consumption, and scenario versatility of unmanned loaders (UAVs). Therefore, how to perform shoveling trajectory planning is a pressing issue that needs to be addressed. Summary of the Invention

[0004] Based on the aforementioned defects and shortcomings of the existing technology, this application proposes a digging trajectory planning method, device, electronic device, and loader. This method describes the energy consumption of the digging trajectory based on a digging trajectory model, takes minimizing the energy consumption of the digging trajectory as the optimization objective, constructs an objective function for the trajectory generation problem, and establishes constraints based on preset bucket full rate thresholds, preset variable thresholds, and preset digging depths. The objective function is then optimally solved based on these constraints to obtain the target digging trajectory, thereby achieving digging trajectory planning, improving digging efficiency, and reducing digging energy consumption.

[0005] According to a first aspect of the embodiments of this application, a method for planning a digging trajectory is provided, comprising:

[0006] The energy consumption of the shovel trajectory is described based on the shovel trajectory model. The goal is to minimize the energy consumption of the shovel trajectory and construct an objective function for the trajectory generation problem. The shovel trajectory model is used to describe the shovel trajectory, which is the trajectory of the bucket tooth tip when the bucket shovels material.

[0007] Based on the preset full bucket rate threshold, preset variable threshold, and preset digging depth, the constraints of the objective function are constructed.

[0008] Based on the constraints, the objective function is optimally solved to obtain the target digging trajectory.

[0009] According to a second aspect of the embodiments of this application, a digging trajectory planning device is provided, comprising:

[0010] The first construction module is used to describe the energy consumption of the digging trajectory based on the digging trajectory model, and to construct the objective function of the trajectory generation problem by taking the minimum energy consumption of the digging trajectory as the optimization objective; the digging trajectory model is used to describe the digging trajectory, which is the trajectory of the bucket tooth tip when the bucket digs material.

[0011] The second construction module is used to construct the constraints of the objective function based on a preset full bucket rate threshold, a preset variable threshold, and a preset digging depth.

[0012] The solution module is used to optimally solve the objective function based on the constraints to obtain the target digging trajectory.

[0013] According to a third aspect of the embodiments of this application, an electronic device is provided, including a memory and a processor;

[0014] The memory is connected to the processor and is used to store programs;

[0015] The processor is used to implement the digging trajectory planning method as described in the first aspect by running the program in the memory.

[0016] According to a fourth aspect of the embodiments of this application, a loader is provided, wherein the loader is equipped with a digging trajectory planning device as described in the second aspect or an electronic device as described in the third aspect.

[0017] In the aforementioned digging trajectory planning method, device, electronic equipment, and loader, the energy consumption of the digging trajectory can be described based on the digging trajectory model. The goal is to minimize the energy consumption of the digging trajectory, construct an objective function for the trajectory generation problem, and construct constraints based on preset full bucket rate thresholds, preset variable thresholds, and preset digging depths. The objective function is then optimally solved based on the constraints to obtain the target digging trajectory, thus realizing the planning of the digging trajectory. Digging materials based on this target digging trajectory can effectively improve digging efficiency and reduce digging energy consumption. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a flowchart illustrating a method for planning a digging trajectory, as provided in an embodiment of this application.

[0020] Figure 2This is a schematic diagram illustrating a material shoveling process according to an embodiment of this application;

[0021] Figure 3 This is a schematic diagram illustrating a process for processing scanned point cloud data of a material pile, as provided in an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of a digging trajectory proposed in an embodiment of this application;

[0023] Figure 5 This is a schematic diagram illustrating the process of a loader digging materials based on a digging trajectory, as proposed in an embodiment of this application.

[0024] Figure 6 This is a schematic diagram illustrating a horizontally placed bucket according to an embodiment of this application;

[0025] Figure 7 This is a schematic diagram of a digging trajectory planning process proposed in an embodiment of this application;

[0026] Figure 8 This is a schematic diagram of the structure of a digging trajectory planning device proposed in an embodiment of this application;

[0027] Figure 9 This is a schematic diagram of the structure of an electronic device proposed in an embodiment of this application. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] Overview

[0030] As described in the background section, shovel trajectory planning, a crucial component of autonomous shovel technology, is still in its early stages of development. Effective shovel trajectory planning methods will significantly improve the smoothness, efficiency, fuel consumption, and scenario versatility of unmanned loaders. Therefore, how to perform shovel trajectory planning has become an urgent problem to be solved.

[0031] Based on this, the inventors further discovered that by describing the energy consumption of the digging trajectory based on a digging trajectory model, and taking the minimum energy consumption of the digging trajectory as the optimization objective, an objective function for generating the trajectory with the minimum energy consumption is constructed. Constraints are then constructed based on preset full bucket rate thresholds, preset variable thresholds, and preset digging depths. The objective function is then optimally solved based on these constraints to obtain the target digging trajectory, thus realizing the planning of the digging trajectory. Since the optimization objective of the objective function is to minimize the energy consumption of the digging trajectory and the target digging trajectory satisfies the constraints constructed based on the preset full bucket rate threshold, digging materials based on this target digging trajectory can effectively improve digging efficiency and reduce digging energy consumption.

[0032] Based on the above concept, this specification provides a method for planning digging trajectory, which will be described exemplarily below with reference to the accompanying drawings.

[0033] Exemplary methods

[0034] Please see Figure 1 In one exemplary embodiment, a digging trajectory planning method is provided, applied to any electronic device, which may be a loader or a device capable of communicating with a loader. Figure 1 As shown, the shovel trajectory planning method includes steps S101-S103:

[0035] S101: Describe the energy consumption of the digging trajectory based on the digging trajectory model, take the minimum energy consumption of the digging trajectory as the optimization objective, and construct the objective function of the trajectory generation problem.

[0036] Among them, the digging trajectory model is used to describe the digging trajectory, which is the trajectory of the bucket teeth tip when the bucket digs material.

[0037] Generally, the starting point of the movement trajectory of the bucket teeth when the bucket digs material, as described by the digging trajectory model, is the contact point between the material pile in front of the bucket and the ground.

[0038] S102: Based on the preset full bucket rate threshold, preset variable threshold, and preset digging depth, construct the constraints of the objective function.

[0039] The preset bucket full rate threshold is used to limit the bucket full rate when the bucket is digging material. Generally, the preset bucket full rate threshold includes a maximum bucket full rate and a minimum bucket full rate, or a maximum bucket full rate coefficient and a minimum bucket full rate coefficient.

[0040] Preset variable thresholds are used to limit the values ​​of variables in the objective function described above. These variables describe the digging trajectory, or in other words, are related to the digging trajectory. If there is at least one variable, then there is at least one preset variable threshold; there is a correspondence between variables and preset variable thresholds. Generally, similar to the preset bucket full rate threshold mentioned above, preset variable thresholds include a maximum variable threshold and a minimum variable threshold.

[0041] The preset digging depth is used to limit the digging depth of the bucket when digging material. The digging depth is the distance / depth that the bucket teeth tip enters the material pile when the bucket digs material.

[0042] It should be noted that the preset full bucket rate threshold, preset variable threshold, and preset digging depth can be predetermined or determined based on actual working conditions.

[0043] S103: Based on the constraints, the objective function is optimally solved to obtain the target digging trajectory.

[0044] Based on the characteristics of the objective function and constraints, a suitable optimization algorithm is selected, such as gradient descent, Newton's method, or conjugate gradient method. The selected optimization algorithm is then used to iteratively solve the problem, gradually approaching the optimal solution. Finally, the optimal solution and the objective function value are output to obtain the target shovel trajectory.

[0045] In this embodiment, based on the digging trajectory model, the energy consumption of the digging trajectory is used as the optimization objective. An objective function for the trajectory generation problem with the lowest energy consumption is established. Based on a preset full bucket rate threshold, a preset variable threshold, and a preset digging depth, constraints are constructed. The objective function is optimally solved based on the constraints to obtain the target digging trajectory, thus realizing the planning of the digging trajectory. Since the target digging trajectory is determined based on the optimization objective of the lowest energy consumption and the constraints constructed with the preset full bucket rate threshold, digging based on this target digging trajectory can effectively ensure the full bucket rate to improve digging efficiency and reduce digging energy consumption.

[0046] In addition, by constructing objective functions and constraints, i.e. modeling based on mathematical derivation, the target digging trajectory with optimal work efficiency and energy consumption (or high work efficiency and low work energy consumption) can be obtained. Compared with simulation and test data modeling, mathematical derivation-based modeling has the advantages of fast modeling, convenient solution and strong versatility.

[0047] In some embodiments, the digging trajectory includes a first straight-line trajectory, a second straight-line trajectory, and a third straight-line trajectory. The first straight-line trajectory is the trajectory of the bucket teeth when the bucket is horizontally inserted into the material pile; the second straight-line trajectory is the trajectory of the bucket teeth when the bucket digs material from the pile; and the third straight-line trajectory is the trajectory of the bucket teeth when the bucket is vertically raised to collect material.

[0048] In other words, the digging trajectory consists of three straight line segments.

[0049] Understandably, the digging trajectory model described above can be determined based on the operator's experience or based on historical digging trajectories.

[0050] At this point, when describing the energy consumption of the shovel trajectory based on the shovel trajectory model, and taking the minimum energy consumption of the shovel trajectory as the optimization objective, the objective function for the trajectory generation problem can be constructed by first determining the trajectory variables based on the first, second, and third straight lines in the shovel trajectory described by the shovel trajectory model, and then describing the energy consumption of the shovel trajectory based on the trajectory variables, taking the minimum energy consumption of the shovel trajectory as the optimization objective, and constructing the objective function.

[0051] Specifically, the lateral distances between the first, second, and third straight-line trajectories are defined as the first trajectory variable, the second trajectory variable, and the third trajectory variable, respectively. Then, based on the first, second, and third trajectory variables, the energy consumption of the digging trajectory is described, and the minimum energy consumption of the digging trajectory is taken as the optimization objective to construct an objective function.

[0052] For example, a schematic diagram of material excavation based on an excavation trajectory including first, second, and third straight-line trajectories can be shown as follows: Figure 2 As shown in the diagram. AB represents the first straight-line trajectory, BC the second, and CD the third. In section AB, the loader with the bucket moves forward, inserting the bucket horizontally into the material pile. In section BC, the loader with the bucket moves forward to scoop the material, simultaneously raising the boom to scoop more material. In section CD, the loader with the bucket moves forward, coordinating with the bucket to collect the material. Additionally, as... Figure 2 As shown, DE is the cross-section of the material pile during material collection. The left side of the cross-section represents the excavated material, and the right side represents the unexcavated material, i.e., the remaining material.

[0053] In this embodiment, based on the digging trajectory model describing the first to third multiple straight-line trajectories, the lateral distances of the first, second, and third straight-line trajectories are determined as the first, second, and third trajectory variables, respectively. The energy consumption of the digging trajectory is described based on these trajectory variables, and the minimum energy consumption of the digging trajectory is used as the optimization objective to construct an objective function. Since the first to third multiple straight-line trajectories correspond to different actions of the bucket when digging material in a stockpile, constructing the objective function based on the combination of these first to third straight-line trajectories for digging trajectory planning can yield a target digging trajectory that conforms to the digging action rules. Therefore, based on the target digging trajectory, material digging that conforms to the digging action rules can be achieved, resulting in a better material digging effect.

[0054] In some embodiments, the energy consumption of the digging trajectory is described based on the first trajectory variable, the second trajectory variable, and the third trajectory variable. The minimum energy consumption of the digging trajectory is taken as the optimization objective. When constructing the objective function, the surface of the material pile is scanned to obtain the point cloud data of the material pile. Then, based on the point cloud data of the material pile and the digging direction, the slope of the second straight line trajectory is determined. Finally, based on the first to third trajectory variables and the slope of the second straight line trajectory, the energy consumption of the digging trajectory is described. The minimum energy consumption of the digging trajectory is taken as the optimization objective, and the objective function is constructed.

[0055] The digging direction is the direction directly in front of the bucket.

[0056] Optionally, after scanning the surface of the stockpile to obtain point cloud data, a two-dimensional stockpile contour curve is first determined based on the digging direction and the stockpile point cloud data. Then, linear regression is performed on the two-dimensional stockpile contour curve to determine its slope, which is then used as the slope of the second straight-line trajectory. Finally, based on the first, second, and third trajectory variables, combined with the slope of the second straight-line trajectory, the energy consumption of the digging trajectory is described. The minimum energy consumption of the digging trajectory is taken as the optimization objective, and an objective function is constructed.

[0057] Specifically, lidar is used to scan the surface of the material pile to obtain point cloud data of the material pile.

[0058] Specifically, based on the digging direction, the point cloud data of the stockpile is cropped and sampled to obtain point cloud sampling points. Then, the two-dimensional stockpile contour curve is determined based on the point cloud sampling points.

[0059] More specifically, based on the digging direction, the point cloud data of the material pile is cropped to obtain the point cloud data of the material in the area directly in front of the bucket. The point cloud data of the material in this area is sampled to obtain point cloud sampling points. Then, based on the point cloud sampling points, the two-dimensional material pile contour curve is determined.

[0060] The sampling method can be uniform sampling.

[0061] In addition, the average height of the sampling points that are at the same lateral distance from the bucket in the point cloud sampling points is taken until the average height at each position in the digging direction of the bucket is determined. Based on the average height at each position, a curve is formed, namely the two-dimensional material pile outline curve.

[0062] For example, the process of processing the scanned point cloud data of the material pile can be as follows: Figure 3As shown in the diagram. The origin O of the XOY coordinate system is the center of the bucket tooth tip, the digging direction is the Y-axis, the horizontal plane containing the Y-axis is the ground, and the vertical direction is the Z-axis. In this coordinate system, based on the point cloud data of the material pile obtained by LiDAR scanning, the data is cropped according to the selected digging direction Y, i.e., the direction directly in front of the bucket, to obtain the material point cloud data of the area directly in front of the bucket. The cropped point cloud data of the area directly in front of the bucket is then uniformly sampled in the Y-direction to obtain point cloud sampling points. Then, the average z-coordinate z0 of the point cloud sampling points with equal y-coordinates is taken, and all (y, z0) points are projected onto the YOZ plane to form a curve, i.e., a two-dimensional material pile outline curve. This curve and the ground can enclose a two-dimensional area to be dug.

[0063] In this embodiment, based on the scanned point cloud data of the material pile and the digging direction of the bucket, a two-dimensional contour curve of the material pile is determined. The slope of the two-dimensional material pile contour curve, obtained by linear regression, is then used as the slope of the second straight line trajectory in the digging trajectory. Finally, based on the first to third trajectory variables and the slope of the second straight line trajectory, the energy consumption of the digging trajectory is described, and an objective function is constructed. Thus, by solving the objective function, a target digging trajectory adapted to the shape of the material pile can be obtained, reducing digging resistance and improving digging stability when digging based on the target digging trajectory.

[0064] It is understandable that when using a bucket to dig and collect materials, the height of the bucket will change, and the height of the bucket teeth will also change accordingly. The change in the height of the bucket in the digging trajectory will also affect the energy consumption of that digging trajectory.

[0065] Therefore, in some embodiments, the energy consumption of the digging trajectory is described based on the first trajectory variable, the second trajectory variable, and the third trajectory variable, combined with the slope of the second straight trajectory. The goal is to minimize the energy consumption of the digging trajectory. When constructing the objective function, after determining the endpoint height of the second straight trajectory based on the second trajectory variable and the slope of the second straight trajectory, the corresponding boom joint angle and bucket tooth tip change can be determined based on the first and second correlation relationships. Then, this information is combined to describe the energy consumption of the digging trajectory.

[0066] The first correlation is the relationship between the height of the bucket tooth tip and the boom joint angle in the second straight trajectory.

[0067] Specifically, this first association can be represented by a polynomial.

[0068] In addition, the second correlation is the correlation between the change in height of the third straight trajectory and the height of the endpoint.

[0069] Specifically, this second association can also be represented by a polynomial.

[0070] Optionally, the endpoint height of the second straight track is first determined based on the slope of the second trajectory variable and the second straight track. Then, the endpoint boom joint angle, the starting boom joint angle, and the change in bucket tooth tip height of the third straight track are determined.

[0071] Wherein, the endpoint boom joint angle is the boom joint angle corresponding to the endpoint of the second straight line trajectory, and the starting point boom joint angle is the boom joint angle corresponding to the starting point of the second straight line trajectory.

[0072] Specifically, the endpoint boom joint angle is determined based on the endpoint height and the first correlation, and the starting point boom joint angle is determined based on the starting point height of the second straight trajectory and the first correlation.

[0073] Specifically, the change in height of the third straight-line trajectory is determined based on the endpoint height and the second correlation.

[0074] Specifically, based on the endpoint height, starting boom joint angle, endpoint boom joint angle, height change, first trajectory variable, second trajectory variable, and third trajectory variable, the energy consumption of the digging trajectory is described, and the minimum energy consumption of the digging trajectory is taken as the optimization objective to construct an objective function.

[0075] The first and second relationships are described below:

[0076] The inverse kinematics calculation of the loader's working device is complex, and in the second linear trajectory, i.e., the boom lifting and bucket digging stage, there is coupled motion of the bucket and boom joint angle, which is not conducive to solving the optimization problem. In the actual test data of the second linear trajectory, the boom lifting angle and the height of the bucket tooth tip show a fixed pattern. In the third linear trajectory, the change in the height of the bucket tooth tip also shows a fixed pattern with the tooth tip height at the end of the second linear trajectory.

[0077] Therefore, in order to improve the calculation efficiency of the inverse kinematics of the loader's working device, the first correlation relationship can be obtained by using actual test data to perform polynomial fitting on the boom joint angle and the height of the bucket tooth tip (relative to the ground) in the second straight trajectory.

[0078] For example, the first association can be, for example, θ boom =f(y bkt ^3,y bkt ^2,y bkt ,y0). Where, θ boom For the boom joint angle, y bktLet y0 be the height of the bucket tooth tip relative to the ground, and y0 be a constant. Verification has shown that using a third-order or higher fitting order can reduce the fitting accuracy of the boom joint angle to below 1° while maintaining monotonicity. This significantly improves the computational efficiency of the inverse kinematics of the loader's working device, while ensuring solution accuracy.

[0079] Similarly, in order to improve the calculation efficiency of the inverse kinematics of the loader's working device, the change in the height of the bucket tooth tip in the third straight trajectory and the height of the bucket tooth tip at the end point in the second straight trajectory can be fitted by a polynomial using actual test data to obtain the second correlation relationship.

[0080] For example, the second association could be, for instance, d = f(y2^3, y2^2, y2, y 00 Where d is the change in bucket tooth tip height along the third straight trajectory, y2 is the bucket tooth tip height at the endpoint of the second straight trajectory, and y 00 It is a constant.

[0081] For example, a schematic diagram of the digging trajectory can be shown as follows: Figure 4 As shown in the figure. The lateral distance of the first straight line trajectory is a, the lateral distance of the second straight line trajectory is b, the slope of the second straight line trajectory is k, the height of the endpoint of the second straight line trajectory is k·b, the height change of the third straight line trajectory is d, and the lateral distance of the third straight line trajectory is c.

[0082] In this embodiment, when the bucket is scooping material from a stockpile, the bucket teeth only move laterally in the first straight trajectory, while in the second and third straight trajectories, the bucket teeth move both laterally and longitudinally. The endpoint height of the second straight trajectory is determined based on the second trajectory variables and their corresponding slopes. Based on the endpoint height and starting height of the second straight trajectory, combined with the first correlation relationship, the endpoint boom joint angle and the starting boom joint angle are determined. Based on the endpoint height of the second straight trajectory, combined with the second correlation relationship, the height change of the third straight trajectory is determined. This allows for a more accurate and comprehensive description of the energy consumption of the straight trajectory, thereby more accurately determining the target scooping trajectory and reducing energy consumption. Furthermore, polynomial fitting of the first and second correlation relationships based on measured data can significantly reduce the computational load when determining the starting and ending boom joint angles and height changes, improving the computational efficiency of inverse kinematics while maintaining solution accuracy.

[0083] It is understandable that the energy consumption of the digging trajectory, i.e., the work done by the loader when digging material in the bucket, includes work done by gravity and work done by resistance. Therefore, in some embodiments, the energy consumption of the digging trajectory is described, and minimizing the energy consumption of the digging trajectory is taken as the optimization objective. When constructing the objective function, the work done by gravity and work done by resistance in the digging trajectory can be described first to obtain the work done by gravity function and the work done by resistance function. Then, based on the work done by gravity function and the work done by resistance function, the objective function is constructed.

[0084] Generally, the sum of the work done by gravity and the work done by resistance is determined as the objective function.

[0085] Specifically, work done by gravity includes work done by the gravity of the material, work done by the gravity of the boom, and work done by the gravity of the bucket. Correspondingly, the work done by gravity functions include the work done by the gravity of the material, the work done by the gravity of the boom, and the work done by the gravity of the bucket.

[0086] Specifically, the work done by resistance includes the work done by the horizontal resistance of the bucket and the work done by the vertical resistance of the bucket. Correspondingly, the work done by resistance function includes the work done by the horizontal resistance of the bucket and the work done by the vertical resistance of the bucket.

[0087] In other words, the work done by the gravity of the material, the work done by the gravity of the boom, and the work done by the gravity of the bucket in the digging trajectory are described by obtaining the work function for the gravity of the material, the work function for the gravity of the boom, and the work function for the gravity of the bucket, respectively. Similarly, the work done by the horizontal resistance and the vertical resistance of the bucket in the digging trajectory are described by obtaining the work function for the horizontal resistance and the work function for the vertical resistance of the bucket, respectively. Finally, the sum of these functions is used as the objective function.

[0088] For example, in the example given above Figure 4 In this process, the loader's material scooping based on the scooping trajectory can be described as follows: Figure 5As shown in the diagram. Where O1 is the boom hinge point at the start of the loader's digging trajectory, and O2 is the boom hinge point at the end of the loader's digging trajectory; θ1 is the boom joint angle at the start of the loader's digging trajectory, and θ2 is the boom joint angle at the end of the loader's digging trajectory; M1 is the bucket hinge point at the start of the loader's digging trajectory, and M2 is the bucket hinge point at the end of the loader's digging trajectory; O1M1 represents the boom at the start of the loader's digging trajectory, and O2M... 2 represents the boom of the loader at the end of the digging trajectory; M1N1 represents the bucket of the loader at the beginning of the digging trajectory; M2N2 represents the bucket of the loader at the end of the digging trajectory; A represents the beginning of the digging trajectory, which coincides with the tip of the bucket tooth N1 at the beginning of the digging trajectory; D represents the end of the digging trajectory, which coincides with the tip of the bucket tooth N2 at the end of the digging trajectory; β1 represents the angle between bucket M1N1 and the horizontal plane; β2 represents the angle between bucket M2N2 and the horizontal plane.

[0089] Generally, when the bucket of a loader scoops material based on a scooping trajectory, the boom only performs gravity work on the second linear trajectory. Therefore, more specifically, the work done by the boom's gravity is described based on the boom weight, the distance between the boom's center of mass and the boom hinge point, the angle between the line connecting the boom's center of mass and the boom hinge point and the boom, the height of the bucket teeth at the end position of the second linear trajectory (i.e., the aforementioned endpoint height), the boom joint angle at the beginning of the second linear trajectory, and the boom joint angle at the end of the second linear trajectory, thus obtaining the boom gravity work function.

[0090] The work done by the boom's gravity is determined based on the boom's weight and the boom's travel height. In other words, all the parameters mentioned above, except for the boom's weight, are used to determine the boom's travel height.

[0091] For example, the work done by the boom's gravity can be expressed as:

[0092] W boom =G1·(L1·sin(θ2+γ2)-L1·sin(θ1-γ1)),

[0093] Where θ2=f(y2^3,y2^2,y2,y0).

[0094] Among them, W boom G1 represents the work done by the weight of the boom, L1 represents the distance between the boom's center of mass and the boom hinge point, θ2 represents the boom joint angle at the end of the second straight trajectory, γ1 represents the angle between the line connecting the boom's center of mass and the boom hinge point when the loader is at the starting point and the boom, γ2 represents the angle between the line connecting the boom's center of mass and the boom hinge point when the loader is at the end point and the boom, θ1 represents the boom joint angle at the starting point of the second straight trajectory, y2 represents the end point height, and y0 is a constant.

[0095] Generally, when the bucket of a loader scoops material based on a scooping trajectory, the bucket performs gravity work on the second and third straight-line trajectories. Therefore, more specifically, the gravity work done by the bucket is described based on the endpoint height of the second straight-line trajectory, the height change of the third straight-line trajectory, the boom hinge point height, the boom length, the boom joint angle at the endpoint of the second straight-line trajectory, the bucket length, the empty weight of the bucket, the distance between the bucket's center of mass and the bucket hinge point, and the angle between the line connecting the bucket's center of mass and the boom hinge point and the bucket itself, thus obtaining the bucket gravity work function.

[0096] The bucket gravity work function is determined based on the bucket weight and the bucket's travel height. In other words, all parameters except the unloaded weight of the bucket are used to determine the bucket's travel height.

[0097] For example, the work done by gravity in the bucket can be expressed as follows:

[0098] W bkt =G2·(OM·sin(θ2)+L2·sin(θ2+β2+δ2)-OM·sin(θ1)-L2·sin(θ1+β1+δ1)),

[0099] in,

[0100]

[0101] y3 = k·b + d.

[0102] Among them, W bkt G2 represents the work done by the bucket's gravity, G2 represents the empty weight of the bucket, OM represents the boom length, θ2 represents the boom joint angle at the end of the second straight trajectory, θ1 represents the boom joint angle at the beginning of the second straight trajectory, L2 represents the distance between the bucket's center of mass and the bucket's hinge point, δ1 represents the angle between the line connecting the bucket's center of mass and the bucket's hinge point and the bucket when the loader is at the starting point, δ2 represents the angle between the line connecting the bucket's center of mass and the bucket's hinge point and the bucket when the loader is at the starting point, β1 represents the angle between the bucket and the horizontal plane (or the bucket joint angle) when the loader is at the starting point, β2 represents the angle between the bucket and the horizontal plane when the loader is at the end point, y3 represents the total height the bucket rises while digging material, MN represents the bucket length, k is the slope of the second straight trajectory in the digging trajectory, b is the lateral distance of the second straight trajectory, and d is the change in the height of the bucket teeth tip in the third straight trajectory.

[0103] Generally, when the bucket of a loader scoops material based on a scooping trajectory, the material does work due to gravity on the second and third straight trajectories. Therefore, more specifically, based on material density, bucket width, material pile sampling step size in the scooping direction, material height corresponding to each step size, number of samples of the actual scooping area in the scooping direction, distance between the material's center of mass and the bucket hinge point, distance between the material's center of mass and the boom hinge point, and the angle between the line connecting the material's center of mass and the bucket hinge point and the bucket, the work done by gravity of the material is described, resulting in the material gravity work function.

[0104] The work done by gravity is determined based on the material's weight and the height it moves. In other words, all parameters except those used to determine the material's weight are used to determine the height it moves.

[0105] For example, the work done by gravity on the material is:

[0106] Among them, W mat This represents the work done by gravity on the material, 9.8 represents the gravity coefficient, ρ represents the density of the material, and B... bkt The width of the bucket is represented by n, the actual number of samples taken in the digging direction is represented by ss, and the sampling step size of the material pile in the digging direction is represented by h. i L1 represents the material height corresponding to each step length, L2 represents the distance between the material's center of mass and the bucket hinge point, and L3 represents the distance between the material's center of mass and the boom hinge point. For an introduction to other parameters in the material gravity work function, please refer to the above content, which will not be repeated here.

[0107] Generally, when the bucket of a loader scoops material based on a scooping trajectory, the bucket performs longitudinal resistance work on the second and third straight trajectories. Therefore, more specifically, the longitudinal resistance work of the bucket is described based on the scooping resistance coefficient, the width of the bucket, the scooping depth of the bucket, the longitudinal distance (i.e., height) of the second straight trajectory, the longitudinal distance of the third straight trajectory, the weighting coefficient of the longitudinal force on the second straight trajectory, and the weighting coefficient of the longitudinal force on the third straight trajectory, thus obtaining the bucket longitudinal resistance work function.

[0108] The work function of the bucket's longitudinal resistance is determined based on the bucket's longitudinal resistance and the bucket's longitudinal travel distance. In other words, all the parameters mentioned above, except those used to determine the bucket's longitudinal resistance, are used to determine the bucket's longitudinal travel distance.

[0109] For example, the work function of the longitudinal resistance of the bucket is W y =F y ·(w4•k•b+w5•d).

[0110] Among them, F y =2.2•k5•B bkt·D bkt .

[0111] Among them, W y The value represents the work done by the longitudinal resistance of the bucket; w4 represents the weighting coefficient of the longitudinal force on the second straight trajectory; w5 represents the weighting coefficient of the longitudinal force on the third straight trajectory; F y D represents the longitudinal resistance of the bucket, k5 represents the digging resistance coefficient, and D bkt This indicates the (lateral) digging depth of the bucket. For an introduction to other parameters in the bucket's longitudinal resistance work function, please refer to the above content, which will not be repeated here.

[0112] It should be noted that w4 is generally less than w5.

[0113] Generally, when the bucket of a loader scoops material based on a scooping trajectory, the bucket performs lateral resistance work in the first, second, and third straight trajectories. Therefore, more specifically, based on factors such as block size coefficient, material type coefficient, stockpile height coefficient, bucket shape coefficient, bucket width, scooping depth, the lateral distance between the first and third straight trajectories, and the weighting coefficient of the lateral forces on the first and third straight trajectories, the lateral resistance work function of the bucket is described.

[0114] For example, the work function of the lateral resistance of the bucket is W. x =F x ·(w1•a+w2·b+w3·c).

[0115] Among them, F x =10^5·k1·k2.k3·k4·B bkt ·D bkt ^1.25.

[0116] Among them, W x The work done by the lateral resistance of the bucket is represented by F, where a, b, and c represent the lateral distances of the first, second, and third straight trajectories, respectively, and w1, w2, and w3 represent the weighting coefficients of the lateral forces on the first, second, and third straight trajectories, respectively. x The lateral resistance of the bucket is represented by k1, k2, k3, and k4, which represent the block size coefficient, material type coefficient, stockpile height coefficient, and bucket shape coefficient, respectively. bkt B indicates the (lateral) digging depth of the bucket. bkt Indicates the width of the bucket.

[0117] In summary, for example, the energy consumption of the digging trajectory is (i.e., the objective function is) W = W boom +W bkt +W x +W y +W mat .

[0118] In this embodiment, an objective function is constructed based on the description of the energy consumption of the digging trajectory. The target digging trajectory with the lowest energy consumption that meets the constraints can be determined based on the optimal solution of the objective function, which effectively reduces the energy consumption of the loading vehicle when digging materials based on the target digging trajectory and saves resources.

[0119] In some embodiments, the preset bucket fill rate threshold includes a maximum bucket fill rate threshold and a minimum bucket fill rate threshold. In this case, when constructing constraints for the objective function based on the preset bucket fill rate threshold, preset variable thresholds, and a preset digging depth, bucket fill rate constraints are constructed based on the maximum and minimum bucket fill rate thresholds, variable constraints are constructed based on the preset variable thresholds, and digging depth constraints are constructed based on the preset bucket depth.

[0120] Optionally, when constructing the bucket rate constraint based on the maximum and minimum bucket rate thresholds, the volume of material scooped by the bucket is determined based on the material pile sampling step length, the material height corresponding to each step length, the slope of the second straight trajectory, the height change of the third straight trajectory, the first trajectory variable, the second trajectory variable, the third trajectory variable, and the bucket width. Then, the bucket rate constraint is constructed based on the maximum and minimum bucket rate thresholds, the rated capacity of the bucket, and the volume of material scooped by the bucket.

[0121] For example, the full-bucket rate constraint is k6·V max ≤S mat ·B bkt ≤k7·V max .

[0122] Where k6 and k7 represent the minimum and maximum full-bucket ratio coefficients, respectively, V max S indicates the rated capacity of the bucket. mat B represents the area of ​​material excavated by the bucket. bkt S represents the width of the bucket. mat ·B bkt This indicates the volume of material excavated by the bucket.

[0123] For example, combined Figure 4 The diagram showing the digging trajectory illustrates that the area of ​​material excavated by the bucket, i.e., the excavated earthwork area, is bounded by straight line segments AB, BC, CD, DE and the upper boundary AE of the material pile. The formula for calculating this area is: The parameters in this calculation formula can be found above and will not be repeated here. At this point, the volume of material excavated by the bucket can be expressed as V = S mat *B bkt Where V represents the volume of material excavated by the bucket.

[0124] The preset variable thresholds mentioned above include the maximum and minimum variable thresholds.

[0125] For example, variable constraints include, for instance, 0 ≤ a ≤ a max 0≤b≤b max and 0≤c≤c max .

[0126] Where a, b, and c represent the lateral distances of the first, second, and third straight-line trajectories, respectively; that is, a, b, and c represent the first, second, and third trajectory variables, respectively. The maximum variable threshold for the first trajectory variable a is a_{n+1}. max The minimum variable threshold is 0, and the maximum variable threshold of the second trajectory variable b is b. max The minimum variable threshold is 0, and the maximum variable threshold of the third trajectory variable c is c. max The minimum variable threshold is 0.

[0127] Based on the bucket height, the slope of the second straight trajectory, and the angle between the target tooth tips, the preset digging depth is determined, and based on the preset digging depth, digging depth constraints are constructed. The target tooth tip angle is the angle between the line connecting the upper and lower tooth tips when the bucket is placed horizontally and the ground.

[0128] The preset excavation depth is used to constrain the first trajectory variable a.

[0129] For example, the digging depth constraint is as follows:

[0130] Where a represents the first trajectory variable, h bkt The height of the bucket when it is placed horizontally (or laid flat) is indicated by α1, which represents the angle between the line connecting the tips of the upper and lower teeth of the bucket and the ground when it is placed horizontally.

[0131] For example, a schematic diagram of a horizontally placed bucket can be shown as follows: Figure 6 As shown. Where h bkt α1 is the height of the bucket when it is placed horizontally (or laid flat), and α1 is the angle between the line connecting the tips of the upper and lower teeth of the bucket and the ground when it is placed horizontally.

[0132] In this embodiment, based on a preset full bucket rate threshold, a preset variable threshold, and a preset digging depth, corresponding full bucket rate constraints, variable constraints, and digging depth constraints are constructed. In this way, when solving the objective function based on the constraints, the full bucket rate, variables, and digging depth can be kept within a reasonable range, ensuring the digging efficiency when digging materials based on the solved target digging trajectory.

[0133] In some embodiments, when the objective function is optimally solved based on constraints to obtain the target excavation trajectory, the objective function is optimally solved based on constraints to obtain the target first trajectory variable, the target second trajectory variable, and the target third trajectory variable. Based on the target first trajectory variable, the first trajectory is determined; based on the slope of the target second trajectory variable and the second straight line trajectory, the second trajectory is determined; based on the endpoint height of the second trajectory and the target third trajectory variable, the third trajectory is determined; finally, based on the first trajectory, the second trajectory, and the third trajectory, the target excavation trajectory is determined.

[0134] Specifically, the change in height of the third trajectory can be determined based on the aforementioned second correlation and the endpoint height of the second trajectory.

[0135] In this embodiment, the target digging trajectory is determined based on the result of the optimal solution of the objective function, and the digging trajectory is planned. Material digging based on the target digging trajectory can effectively improve digging efficiency and reduce digging energy consumption.

[0136] For example, the process of shovel trajectory planning can be as follows: Figure 7 As shown, three-dimensional point cloud data of the material pile is collected by LiDAR, i.e., the material pile point cloud data. This data is processed to obtain the two-dimensional material pile edge (i.e., the aforementioned two-dimensional material pile contour curve). Linear regression is performed on this two-dimensional material pile edge to determine the slope of the second straight line trajectory in the digging trajectory. Simultaneously, based on loader structural parameters and bucket follow-up data, polynomial fitting is performed, specifically polynomial fitting of the boom joint angle and bucket tooth tip height, and polynomial fitting of the change in bucket tooth tip height of the third straight line trajectory with the bucket tooth tip height at the endpoint of the second straight line trajectory. Next, an optimization problem description is performed, describing the energy consumption of the digging trajectory, resulting in an objective function. Then, the objective function is solved to obtain the optimal control parameters a, b, and c, i.e., the lateral distances of the first, second, and third straight lines. Finally, it is determined whether the optimal control parameters satisfy the constraints, i.e., whether the target digging trajectory satisfies the aforementioned full bucket rate constraint, variable constraint, and digging depth constraint. If yes, the process ends; otherwise, the collected point cloud data of the material pile is reprocessed to determine the two-dimensional edge of the material pile, and the subsequent process is carried out.

[0137] Exemplary device

[0138] Correspondingly, such as Figure 8 As shown in the figure, this application embodiment also provides a digging trajectory planning device, which includes a first construction module 801, a second construction module 802, and a solution module 803.

[0139] in,

[0140] The first construction module 801 is used to describe the energy consumption of the digging trajectory based on the digging trajectory model, and to construct the objective function of the trajectory generation problem by taking the minimum energy consumption of the digging trajectory as the optimization objective; the digging trajectory model is used to describe the digging trajectory, and the digging trajectory is the trajectory of the bucket tooth tip when the bucket digs material.

[0141] The second construction module 802 is used to construct the constraints of the objective function based on the preset full bucket rate, preset variable threshold and preset digging depth;

[0142] The solver module 803 is used to perform optimal solution of the objective function based on the constraints to obtain the target digging trajectory.

[0143] The digging trajectory planning device provided in this embodiment belongs to the same concept as the digging trajectory planning method provided in the above embodiments of this application. It can execute the method provided in any of the above embodiments of this application and has the corresponding functional modules and beneficial effects of the method. Technical details not described in detail in this embodiment can be found in the specific processing content of the digging trajectory planning method provided in the above embodiments of this application, and will not be repeated here.

[0144] The functions implemented by the first building module 801, the second building module 802, and the solving module 803 can be implemented by the same or different processors calling software, and this application embodiment does not limit this.

[0145] Exemplary electronic devices

[0146] Another embodiment of this application also provides an electronic device, see [link to relevant documentation] Figure 9 As shown, the electronic device includes a memory 900 and a processor 910.

[0147] The memory 900 is connected to the processor 910 and is used to store programs;

[0148] The processor 910 is used to implement the digging trajectory planning method disclosed in any of the above embodiments by running the program stored in the memory 900.

[0149] Specifically, the electronic device may also include: a bus, a communication interface 920, an input device 930, and an output device 940.

[0150] The processor 910, memory 900, communication interface 920, input device 930, and output device 940 are interconnected via a bus. Among them:

[0151] A bus can include a pathway for transmitting information between various components of a computer system.

[0152] The processor 910 can be a general-purpose processor, such as a general-purpose central processing unit (CPU), a microprocessor, etc., or an application-specific integrated circuit (ASIC), or one or more integrated circuits used to control the execution of the program of the present application. It can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0153] The processor 910 may include a main processor, as well as a baseband chip, modem, etc.

[0154] The memory 900 stores a program for executing the technical solution of this application, and may also store an operating system and other critical business functions. Specifically, the program may include program code, which includes computer operation instructions. More specifically, the memory 900 may include read-only memory (ROM), other types of static storage devices capable of storing static information and instructions, random access memory (RAM), other types of dynamic storage devices capable of storing information and instructions, disk storage, flash memory, etc.

[0155] Input device 930 may include a device for receiving user input data and information, such as a keyboard, mouse, camera, scanner, light pen, voice input device, touch screen, pedometer, or gravity sensor.

[0156] Output device 940 may include devices that allow information to be output to a user, such as a display screen, printer, speaker, etc.

[0157] The communication interface 920 may include a device that uses any transceiver to communicate with other devices or communication networks, such as Ethernet, Radio Access Network (RAN), Wireless Local Area Network (WLAN), etc.

[0158] The processor 910 executes the program stored in the memory 900 and calls other devices, which can be used to implement any of the steps of the digging trajectory planning method provided in the above embodiments of this application.

[0159] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the electronic device to which the present application is applied. The specific electronic device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0160] This application also proposes a chip, which includes a processor and a data interface. The processor reads and runs a program stored in a memory through the data interface to execute the digging trajectory planning method described in any of the above embodiments. For the specific processing procedure and its beneficial effects, please refer to the above embodiments of the digging trajectory planning method.

[0161] This application also provides a loader, which is equipped with the above-mentioned digging trajectory planning device or the above-mentioned electronic device.

[0162] In addition to the methods and devices described above, embodiments of this application provide a computer program product comprising computer program instructions that, when executed by a processor, cause the processor to perform the steps of the digging trajectory planning method according to various embodiments of this application as described in the "Exemplary Methods" section of this specification.

[0163] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0164] Furthermore, embodiments of this application also propose a storage medium storing a computer program, which is executed by a processor in the steps of the digging trajectory planning method according to various embodiments of this application described in the "Exemplary Methods" section above.

[0165] It is understood that the specific examples in this document are only intended to help those skilled in the art better understand the implementation methods of this specification, and are not intended to limit the scope of this specification.

[0166] It is understood that in the various embodiments described in this specification, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments described in this specification.

[0167] It is understood that the various implementation methods described in this specification can be implemented individually or in combination, and the implementation methods in this specification are not limited in this respect.

[0168] Unless otherwise stated, all technical and scientific terms used in the embodiments of this specification have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this specification. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. The singular forms "a," "the," and "the" as used in the embodiments of this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0169] It is understood that the processor in the embodiments of this specification can be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method embodiments can be completed by integrated logic circuits in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this specification. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this specification can be directly implemented by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above methods.

[0170] It is understood that the memory in the embodiments of this specification may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory may be random access memory (RAM). It should be noted that the memory in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0171] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this specification.

[0172] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the aforementioned method implementations, and will not be repeated here.

[0173] In the several embodiments provided in this specification, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0174] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0175] In addition, the functional units in the various embodiments of this specification can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0176] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of this specification, in essence, or the parts that contribute to the prior art, or parts of the technical solutions, can be embodied in the form of software products. These computer software products are stored in a storage medium and include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this specification. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0177] The above description is merely a specific embodiment of this specification, but the scope of protection of this specification is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this specification should be included within the scope of protection of this specification. Therefore, the scope of protection of this specification should be determined by the scope of the claims.

Claims

1. A method for planning shovel trajectories, characterized in that, The method includes: The energy consumption of the shovel trajectory is described based on the shovel trajectory model. The goal is to minimize the energy consumption of the shovel trajectory and construct an objective function for the trajectory generation problem. The shovel trajectory model is used to describe the shovel trajectory, which is the trajectory of the bucket tooth tip when the bucket shovels material. Based on the preset full bucket rate threshold, preset variable threshold, and preset digging depth, the constraints of the objective function are constructed. Based on the aforementioned constraints, the objective function is optimally solved to obtain the target shovel trajectory; The digging trajectory includes a first straight-line trajectory, a second straight-line trajectory, and a third straight-line trajectory. The first straight-line trajectory is the trajectory of the bucket teeth when the bucket is horizontally inserted into the material pile. The second straight-line trajectory is the trajectory of the bucket teeth when the bucket digs material from the material pile. The third straight-line trajectory is the trajectory of the bucket teeth when the bucket is vertically raised to collect material. The energy consumption of the digging trajectory is described based on the digging trajectory model, and the minimum energy consumption of the digging trajectory is taken as the optimization objective. An objective function for the trajectory generation problem is constructed, including: determining the lateral distances of the first straight-line trajectory, the second straight-line trajectory, and the third straight-line trajectory as the first trajectory variable, the second trajectory variable, and the third trajectory variable, respectively; describing the energy consumption of the digging trajectory based on the first trajectory variable, the second trajectory variable, and the third trajectory variable, and taking the minimum energy consumption of the digging trajectory as the optimization objective to construct the objective function.

2. The digging trajectory planning method according to claim 1, characterized in that, The energy consumption of the digging trajectory is described based on the first trajectory variable, the second trajectory variable, and the third trajectory variable. The goal is to minimize the energy consumption of the digging trajectory, and the objective function is constructed as follows: The surface of the material pile is scanned to obtain point cloud data of the material pile; Based on the digging direction and the point cloud data of the material pile, a two-dimensional material pile outline curve is determined, wherein the digging direction is the front of the bucket; Linear regression processing is performed on the two-dimensional material pile profile curve to determine the slope of the two-dimensional material pile profile curve; The slope of the two-dimensional material pile profile is determined as the slope of the second straight line trajectory; Based on the first trajectory variable, the second trajectory variable, and the third trajectory variable, and combined with the slope of the second straight line trajectory, the energy consumption of the digging trajectory is described, and the goal function is constructed by taking the minimum energy consumption of the digging trajectory as the optimization objective.

3. The shovel trajectory planning method based on claim 2, characterized in that, The energy consumption of the digging trajectory is described based on the first trajectory variable, the second trajectory variable, and the third trajectory variable, combined with the slope of the second straight line trajectory. The goal is to minimize the energy consumption of the digging trajectory, and the objective function is constructed as follows: Based on the slope of the second trajectory variable and the second straight line trajectory, determine the endpoint height of the second straight line trajectory; Based on the endpoint height and the first correlation, the endpoint boom joint angle is determined. The first correlation is the correlation between the height of the bucket tooth tip and the boom joint angle in the second straight trajectory. The endpoint boom joint angle is the boom joint angle corresponding to the endpoint of the second straight trajectory. Based on the starting height of the second straight trajectory and the first correlation, the starting boom joint angle is determined, wherein the starting boom joint angle is the boom joint angle corresponding to the starting point of the second straight trajectory; Based on the endpoint height and the second correlation, the height change of the third straight track is determined, where the second correlation is the correlation between the height change of the third straight track and the endpoint height. Based on the endpoint height, the starting boom joint angle, the endpoint boom joint angle, the height change, the first trajectory variable, the second trajectory variable, and the third trajectory variable, the energy consumption of the digging trajectory is described, and the minimum energy consumption of the digging trajectory is taken as the optimization objective to construct the objective function.

4. The digging trajectory planning method according to claim 3, characterized in that, The energy consumption of the digging trajectory is described, and the objective function is constructed with minimizing the energy consumption of the digging trajectory as the optimization objective, including: The work done by gravity of the material, the work done by gravity of the boom, and the work done by gravity of the bucket in the digging trajectory are described, and the work done by gravity of the material, the work done by gravity of the boom, and the work done by gravity of the bucket are obtained respectively. The work done by the horizontal resistance of the bucket and the work done by the vertical resistance of the bucket in the digging trajectory are described, and the work functions of the horizontal resistance and the vertical resistance of the bucket are obtained respectively. The sum of the work done by the material gravity, the work done by the boom gravity, the work done by the bucket gravity, the work done by the bucket horizontal resistance, and the work done by the bucket vertical resistance is determined as the objective function.

5. The digging trajectory planning method according to claim 4, characterized in that, The preset full-bottle rate threshold includes a maximum full-bottle rate threshold and a minimum full-bottle rate threshold. The constraints for constructing the objective function based on a preset full bucket rate threshold, a preset variable threshold, and a preset digging depth include: The volume of material scooped by the bucket is determined based on the sampling step length of the material pile, the material height corresponding to each step length, the slope of the second straight trajectory, the height change of the third straight trajectory, the first trajectory variable, the second trajectory variable, the third trajectory variable, and the bucket width. Based on the maximum bucket full rate threshold, the minimum bucket full rate threshold, the rated capacity of the bucket, and the volume of material scooped by the bucket, a bucket full rate constraint condition is constructed. Based on the preset variable thresholds, variable constraints are constructed; Based on the bucket height, the slope of the second straight trajectory, and the angle between the target tooth tips, a preset digging depth is determined, and based on the preset digging depth, digging depth constraints are constructed. The target tooth tip angle is the angle between the line connecting the upper and lower tooth tips and the ground when the bucket is placed horizontally.

6. The digging trajectory planning method according to claim 5, characterized in that, The step of optimally solving the objective function based on the constraints to obtain the target excavation trajectory includes: Based on the constraints, the objective function is optimally solved to obtain the first objective trajectory variable, the second objective trajectory variable, and the third objective trajectory variable; Based on the target first trajectory variable, determine the first trajectory; The second trajectory is determined based on the slope of the target second trajectory variable and the second straight line trajectory; The third trajectory is determined based on the endpoint height of the second trajectory and the target third trajectory variables; The target digging trajectory is determined based on the first trajectory, the second trajectory, and the third trajectory.

7. A digging trajectory planning device, characterized in that, The device includes: The first construction module is used to describe the energy consumption of the digging trajectory based on the digging trajectory model, and to construct the objective function of the trajectory generation problem by taking the minimum energy consumption of the digging trajectory as the optimization objective; the digging trajectory model is used to describe the digging trajectory, which is the trajectory of the bucket tooth tip when the bucket digs material. The second construction module is used to construct the constraints of the objective function based on the preset full bucket rate, preset variable thresholds, and preset digging depth. The solution module is used to perform optimal solution of the objective function based on the constraints to obtain the target digging trajectory; The digging trajectory includes a first straight-line trajectory, a second straight-line trajectory, and a third straight-line trajectory. The first straight-line trajectory is the trajectory of the bucket teeth when the bucket is horizontally inserted into the material pile. The second straight-line trajectory is the trajectory of the bucket teeth when the bucket digs material from the material pile. The third straight-line trajectory is the trajectory of the bucket teeth when the bucket is vertically raised to collect material. The energy consumption of the digging trajectory is described based on the digging trajectory model, and the minimum energy consumption of the digging trajectory is taken as the optimization objective. An objective function for the trajectory generation problem is constructed, including: determining the lateral distances of the first straight-line trajectory, the second straight-line trajectory, and the third straight-line trajectory as the first trajectory variable, the second trajectory variable, and the third trajectory variable, respectively; describing the energy consumption of the digging trajectory based on the first trajectory variable, the second trajectory variable, and the third trajectory variable, and taking the minimum energy consumption of the digging trajectory as the optimization objective to construct the objective function.

8. An electronic device, characterized in that, Including memory and processor; The memory is connected to the processor and is used to store programs; The processor is used to implement the digging trajectory planning method as described in any one of claims 1 to 6 by running the program in the memory.

9. A loader, characterized in that, The loader is equipped with the digging trajectory planning device as described in claim 7 or the electronic device as described in claim 8.

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