Design method and device of series-parallel mining electric shovel and readable storage medium

Abstract

The invention provides a series-parallel mining electric shovel design method and device and a readable storage medium, and the method comprises the steps that according to the motion characteristics and the freedom degree requirement of a mining electric shovel, the mining electric shovel is subjected to shape integration based on the spinor theory, and multiple alternative configurations of the mining electric shovel are determined; discrete element simulation is conducted on the mining electric shovels of the multiple alternative configurations, and the dynamic excavation resistance of the mining electric shovels of the multiple alternative configurations is determined; according to the dynamic excavation resistance, the dynamical models of the mining electric shovel of the multiple alternative configurations are solved, and a dynamical simulation result is determined; according to the dynamic simulation results of the mining electric shovels of the multiple alternative configurations, the better configuration of the mining electric shovel is determined on the basis of the motion continuity, singularity and dynamic excavation resistance of the mining electric shovel; and according to a multi-target scale synthesis method, establishing a parameterized model, a boundary condition and a multi-target design function of the better configuration so as to carry out multi-target scale synthesis on the better configuration.

Description

Technical Field

[0001] The present application relates to the field of machinery, and more specifically, to a design method and device for a hybrid mining electric shovel, and a readable storage medium. Background Art

[0002] Mining electric shovels are key equipment used in mining for excavating large pieces of ore and earth. Traditional mining electric shovels have a relatively simple configuration, usually a planar two-degree-of-freedom structure.

[0003] Currently, research on electric shovel excavation devices focuses primarily on lightweighting, algorithm optimization, and dynamics. Direct structural innovation is relatively rare, and kinematic analysis often considers the shovel as a series mechanism. In reality, the shovel's rotating platform is considered the static platform, the boom is a series component, and the corresponding excavation section is a parallel mechanism. Therefore, from a structural perspective, mining electric shovels are hybrid devices.

[0004] Compared to the aforementioned two-degree-of-freedom (DOF) electric shovel mechanism, a multi-DOF (e.g., three-DOF) hybrid electric shovel is more effective in reducing maximum digging resistance, especially in mining areas with steep slopes and complex working environments. This significantly improves the shovel's operating efficiency and stability. Related art design of multi-DOF electric shovels relies heavily on empirical experience or traditional design methods, which have significant limitations. For example, when designing an electric shovel, simply replacing some kinematic joints on the moving platform or making minor modifications similar to existing solutions (such as adjusting connecting rod length or cylinder stroke) results in a single design. Furthermore, evaluation of new configurations often relies solely on isolated kinematic or dynamic parameters. This approach results in new designs that only meet basic functional requirements, with limited improvements to overall performance. Furthermore, the lack of reliable evaluation metrics and subsequent comprehensive research on the mechanism scale for newly designed electric shovel configurations results in low design efficiency and integrity. Summary of the Invention

[0005] This application mainly provides a design method and device for a hybrid mining electric shovel, and a readable storage medium. The technical solution of this application is implemented as follows: In a first aspect, a design method for a hybrid electric mining shovel is provided, the method comprising: performing type synthesis on the electric mining shovel based on the screw theory according to the motion characteristics and degree of freedom requirements of the electric mining shovel, and determining multiple alternative configurations of the electric mining shovel; performing discrete element simulation on the electric mining shovels of the multiple alternative configurations, and respectively determining the dynamic excavation resistance of the electric mining shovels of the multiple alternative configurations; solving the dynamic models of the electric mining shovels of the multiple alternative configurations according to the dynamic excavation resistance, and determining dynamic simulation results; determining the optimal configuration of the electric mining shovel based on the motion continuity, singularity and dynamic excavation resistance of the electric mining shovel according to the dynamic simulation results of the electric mining shovels of the multiple alternative configurations; and establishing a parameterized model, boundary conditions and multi-objective design function of the optimal configuration according to a multi-objective scale synthesis method to perform multi-objective scale synthesis on the optimal configuration.

[0006] The mining shovel design method provided in the embodiments of the present application efficiently generates multiple alternative configurations based on screw theory, evaluates the dynamic performance of each configuration through discrete element simulation and dynamics joint solution, determines the optimal configuration based on analysis of motion continuity, singularity, and dynamic excavation resistance, then parametrically models the configuration, sets boundary conditions, establishes a multi-objective design function, and uses a genetic algorithm to search for parameter combinations. Ultimately, the optimal structural parameters and installation position angle parameters for the configuration are obtained, completing the high-performance dimensional synthesis of the hybrid mechanism. This method not only improves the scientific nature and accuracy of the configuration design, but also effectively improves the operating efficiency and stability of the mining shovel under complex working conditions, achieving an integrated design of the mining shovel from configuration synthesis to dimensional parameters.

[0007] In some embodiments, the discrete element simulation is performed on the multiple alternative configurations of the mining electric shovels to respectively determine the dynamic excavation resistance of the multiple alternative configurations of the mining electric shovels, including: establishing discrete element simulation models of the multiple alternative configurations of the mining electric shovels respectively; establishing an ore particle model in the discrete element simulation software; setting a driving function for each of the multiple discrete element simulation models in the discrete element simulation software; and solving the dynamic excavation resistance of each of the alternative configurations of the mining electric shovel using the discrete element simulation software.

[0008] Based on the above technical means, by establishing an ore particle model, the mechanical response between electric shovels of different configurations and ore can be accurately predicted. At the same time, by establishing different types of particle models, the impact of different ore conditions on electric shovel performance can be evaluated, enhancing the adaptability of the design.

[0009] In some embodiments, the dynamic excavation resistance is used to solve the dynamic models of the multiple alternative configurations of the mining electric shovel and determine the dynamic simulation results, including: establishing a dynamic simulation model of each of the alternative configurations of the mining electric shovel in the dynamic simulation software; setting a driving function for each of the dynamic simulation models in the dynamic simulation software, and applying a corresponding dynamic excavation resistance to each of the dynamic models; using the dynamic simulation software to solve each of the dynamic simulation models to obtain the dynamic simulation results of each of the alternative configurations; the dynamic simulation results include the velocity curves, acceleration curves and excavation trajectories of multiple points on the bucket tooth tip.

[0010] Using these technical approaches, a dynamic model of each candidate electric mining shovel configuration is established in dynamic simulation software, along with appropriate drive functions and dynamic excavation resistance. This allows for the velocity and acceleration curves of each bucket tooth tip, as well as the excavation trajectory, to be determined. This allows for an accurate assessment of the motion continuity and stability of each configuration in actual operation, enabling the selection of the optimal configuration and ultimately improving the overall performance and efficiency of the electric mining shovel.

[0011] In some embodiments, determining the optimal configuration of the mining electric shovel based on the motion continuity and singularity of the mining electric shovel includes: determining that the first alternative configuration is the optimal configuration when the dynamic simulation result of the first alternative configuration among the multiple alternative configurations meets the following conditions: the speed curve corresponding to the first alternative configuration changes smoothly and does not have an inflection point; the acceleration curve corresponding to the first alternative configuration changes smoothly, and the acceleration curve does not have an infinite or infinitesimal point.

[0012] The above-mentioned technical approach, through a comprehensive analysis of the changing characteristics of the velocity and acceleration curves, can effectively evaluate the motion continuity and non-singularity performance of a mining shovel in a specific configuration. Only when both types of curves exhibit good smoothness and stability is the configuration considered to have high engineering applicability and reliability, and thus to be the preferred configuration.

[0013] In some embodiments, the mining electric shovel is synthesized based on the screw theory according to the motion characteristics and degree of freedom requirements of the mining electric shovel to determine multiple alternative configurations of the mining electric shovel, including: determining the motion screw system of the moving platform of the mining electric shovel based on the screw theory according to the degrees of freedom and motion characteristics of the mining electric shovel; determining the constrained screw system of the moving platform according to the screw reciprocity theory; determining the constrained screw system of each branch according to the constraint screw system of the moving platform and the motion characteristics of multiple branches of the mining electric shovel; determining the motion screw system of each branch through the screw reciprocity theory according to the constrained screw system of each branch; determining multiple configurations of each branch according to the motion screw system of each branch; and determining multiple alternative configurations of the mining electric shovel according to the multiple configurations of each branch.

[0014] In some embodiments, the constrained spinor system of each branch is determined based on the motion characteristics of the constrained spinor system of the moving platform and the multiple branches of the mining electric shovel, including: determining the dimension of the constrained spinor system of the moving platform based on the dimension of the motion spinor system of the moving platform; decomposing the constrained spinor system of the moving platform based on the number of multiple branches and the motion characteristics of each branch to determine the constraint condition of each branch; determining the constrained spinor system of each branch based on the constraint condition of each branch; wherein the number of independent constraints among all the constraints provided by each branch is consistent with the dimension of the constrained spinor system of the moving platform.

[0015] According to the above technical means, the efficiency and accuracy of configuration design can be improved by decomposing the constraint space of the moving platform into the constraint subspaces of each branch and obtaining the corresponding motion space of the branch through spinor reciprocity.

[0016] In some embodiments, the multiple alternative configurations of the mining electric shovel are determined based on the multiple configurations of each branch chain, including: determining the multiple configurations of each branch chain based on the different arrangement orders of the multiple motion pairs of each branch chain; combining the multiple configurations of each branch chain in the multiple branches to obtain multiple combined configurations of the mining electric shovel; combining the constrained spinor system of each branch chain to determine the constrained spinor system provided to the moving platform by each branch chain in each combined configuration, determining the dimension of the constrained spinor system corresponding to each combined configuration to determine the degree of freedom of motion of each combined configuration; and taking the combined configuration whose degree of freedom in the multiple combined configurations matches the degree of freedom requirement of the mining electric shovel as the alternative configuration.

[0017] In some embodiments, the multi-objective scale synthesis of the preferred configuration includes: establishing constraints of the mining electric shovel during the excavation process based on the preferred configuration; using the structural dimensions and kinematic pair installation parameters in the preferred configuration as design variables to establish a parametric model of the optimal configuration; introducing boundary conditions and design constraints to establish a multi-objective design solution domain; establishing a multi-objective design function of the preferred configuration based on the end trajectory requirements, workspace requirements and energy consumption requirements of the moving platform of the mining electric shovel; and using a genetic algorithm to search for the optimal combination of the structural dimensions and the installation parameters within the multi-objective design solution domain to complete the multi-objective scale synthesis design of the preferred configuration.

[0018] In a second aspect, a design device for a mining electric shovel is provided, the device comprising: a first determination unit for performing type synthesis on the mining electric shovel based on the screw theory according to the motion characteristics and degree of freedom requirements of the mining electric shovel, and determining multiple alternative configurations of the mining electric shovel; a discrete element simulation unit for performing discrete element simulation on the mining electric shovels of the multiple alternative configurations, and respectively determining the dynamic excavation resistance of the mining electric shovels of the multiple alternative configurations; a dynamic simulation unit for solving the dynamic models of the mining electric shovels of the multiple alternative configurations according to the dynamic excavation resistance, and determining dynamic simulation results; a second determination unit for determining the optimal configuration of the mining electric shovel based on the motion continuity, singularity and dynamic excavation resistance of the mining electric shovel according to the dynamic simulation results of the mining electric shovels of the multiple alternative configurations; a scale synthesis unit for establishing a parameterized model, boundary conditions and multi-objective design function of the optimal configuration according to a multi-objective scale synthesis method, so as to perform multi-objective scale synthesis on the optimal configuration.

[0019] According to a third aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium is used to store a computer program, and the computer program executes the method according to the first aspect when executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic flow chart of a method for designing a mining electric shovel according to an embodiment of the present application; Figure 2 This is an example diagram of the structural motion of a three-degree-of-freedom mining electric shovel; Figure 3 A schematic flow chart of a method for determining the dynamic excavation resistance of multiple alternative configurations of electric mining shovels in the electric mining shovel design method provided in an embodiment of the present application; Figure 4 This is a schematic diagram of discrete element simulation of a mining electric shovel; Figure 5A schematic flow chart of a method for solving the dynamic model of multiple alternative configurations of an electric mining shovel in the electric mining shovel design method provided in an embodiment of the present application; Figure 6 This is an example diagram of a dynamic simulation model of a mining electric shovel provided in an embodiment of the present application; Figure 7 A schematic flow chart of a method for determining multiple alternative configurations of an electric mining shovel in the electric mining shovel design method provided in an embodiment of the present application; Figure 8 This is an example diagram of the geometric representation of the 1R2T three-degree-of-freedom mining electric shovel platform motion screw system; Figure 9 for Figure 8 Example diagram of geometric representation of constrained screw system corresponding to the moving screw system; Figure 10 This is a schematic diagram of the kinematic pair of the 1R2T three-degree-of-freedom mining electric shovel branch chain; Figure 11 A schematic flow chart of determining the constraint space of each branch chain in the mining electric shovel design method provided in an embodiment of the present application; Figure 12 A schematic flow chart of determining the motion space of each branch chain in the mining electric shovel design method provided in an embodiment of the present application; Figure 13 A schematic flow chart of a multi-objective scale integration method for a mining electric shovel provided in an embodiment of the present application; Figure 14 Schematic diagram of several possible combination configurations of a three-degree-of-freedom mining electric shovel provided in an embodiment of the present application; Figure 15 A schematic flow chart of a method for designing a mining electric shovel according to another embodiment of the present application; Figure 16 A schematic structural diagram of a design device for a mining electric shovel provided in an embodiment of the present application; Figure 17 A schematic structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0022] It should be noted that the terms "including," "having," and any variations thereof in the embodiments and drawings of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to the process, method, product, or apparatus.

[0023] The terms "first," "second," "third," and "fourth" in the specification and drawings of this application are used to distinguish different objects, not to describe a specific order. In addition, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements, but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0024] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0025] Electric mining shovels are key equipment used in mining to excavate large ore and earth. The rapid development of open-pit mining has increased demand for electric mining shovels. However, with the increasing complexity of mining environments, traditional electric mining shovel designs are no longer able to meet the growing demands for efficiency, safety, and adaptability in modern mines, placing higher demands on their mechanical design and structural innovation.

[0026] Traditional mining electric shovels have a relatively simple configuration. For example, the widely used two-degree-of-freedom (DOF) shovel structure utilizes a hoisting wire rope for lifting motion. When the bucket is activated and the teeth are subjected to strong impact loads, the rope-lifted bucket will experience swaying in all directions, front to back, left to right, and right to left. The rope can also stretch, deform, and even become tangled under the impact of operation, affecting the accuracy of the lifting operation. Frequent use can also lead to strand breakage under impact, reducing the safety and reliability of the equipment. Furthermore, the high friction between the rope and the drum results in significant power consumption in the hoisting motor, significantly reducing the service life of the rope and drum.

[0027] Currently, research on electric shovel excavation devices focuses primarily on lightweighting, algorithm optimization, and dynamics. Direct structural innovation is relatively rare, and kinematic analysis often considers the shovel as a series mechanism. In reality, the shovel's rotating platform is considered the static platform, the boom is a series component, and the corresponding excavation section is a parallel mechanism. Therefore, from a structural perspective, mining electric shovels are hybrid devices.

[0028] Compared to the two-degree-of-freedom (DOF) shovel mechanism described above, a multi-DOF (e.g., three-DOF) shovel is more effective in reducing maximum digging resistance, particularly in mining areas with steep slopes and complex working environments. This significantly improves the shovel's operating efficiency and stability. Related art design of multi-DOF shovels relies heavily on empirical experience or traditional design methods, which present significant limitations. For example, when designing a shovel, some kinematic joints of the moving platform are simply replaced, or minor modifications are made based on existing solutions (e.g., adjusting connecting rod length or cylinder stroke). This approach results in a monotonous design. Furthermore, evaluation of new configurations often relies solely on isolated kinematic or dynamic parameters. This approach results in new designs that only meet basic functional requirements, with limited improvement in overall performance. Furthermore, there is a lack of reliable evaluation metrics for newly designed shovel configurations, and the dimensional integration of the new configuration is rarely considered, resulting in low design efficiency and integrity.

[0029] Therefore, how to break through the limitations of traditional design methods, improve the efficiency and accuracy of mining electric shovel configuration design, and increase the integrity of the mining electric shovel design process has become an urgent problem to be solved.

[0030] In view of the above problems, embodiments of the present application provide a design method and device for a hybrid mining electric shovel, and a computer-readable storage medium.

[0031] Figure 1 is a schematic flow chart of a mining shovel design method provided in an embodiment of the present application, Figure 1 The method includes steps S110-S150.

[0032] In step S110 , according to the motion characteristics and degree of freedom requirements of the mining electric shovel, the mining electric shovel is subjected to type synthesis based on the screw theory to determine multiple candidate configurations of the mining electric shovel.

[0033] In the technical solution of the embodiment of the present application, it is first necessary to clarify the working requirements of the mining electric shovel, that is, the specific achievable motion form of the end actuator of the mining electric shovel mechanism in space.

[0034] Traditional mining shovels typically only achieve 2T motion within the working plane. To improve the working flexibility of mining shovels and reduce digging resistance, they can be configured with a three-degree-of-freedom mechanism, adding a rotational degree of freedom to the moving platform to achieve 1R2T within the working plane. Figure 2 This is a structural example diagram of the motion form of a three-degree-of-freedom mining electric shovel.

[0035] Screw theory is a unified mathematical method for describing the motion and force of rigid bodies in space. It uses screws to express the translation and rotation of a rigid body as a whole. Its core is that any motion of a rigid body can be represented by a set of motion screws. To describe; among them, is a line vector, corresponding to the rotation, It is an even quantity, corresponding to movement, and the combination of the two forms a six-dimensional spinor, which can describe the translation and rotation of a rigid body in space.

[0036] The spinor reciprocity theory is the core of the spinor theory and establishes the motion space and constraint space The relationship between them is orthogonal subspace, and the total dimension of the two is six, which realizes the mutual mapping between the degrees of freedom of motion and the degrees of constraint.

[0037] More specifically, a kinematic spinor system for the working device's dynamic platform is established based on spinor theory, and the dynamic platform's constrained spinor system is solved using reciprocity theory. The dynamic platform's constrained spinor system is then decomposed into the constrained spinors of each branch. Constrained spinors are assigned based on the number of branches and their kinematic characteristics. The kinematic spinors of each branch are then derived using reciprocity theory, thereby determining the kinematic pair combinations of each branch.

[0038] Because the kinematic pairs of each branch can be combined in a variety of ways, the resulting configurations are also different, resulting in a variety of alternative configurations. For example, in one configuration, a branch might adopt a RUS (rotation-slip-rotation) or RSS (rotation-slip-slip) configuration, while in another, it might adopt an RRR (three rotation pairs) or an RPR (rotation-slip-rotation) configuration. Different branch combinations lead to different kinematic pair arrangements, which in turn affects the dynamic performance and structural stability of the entire mechanism.

[0039] The above configuration synthesis process can be completed with the help of computer-aided design software. For example, platforms such as MATLAB and ADAMS can be used to establish a spinor space and automatically generate multiple possible configuration schemes using algorithms. After screening, several candidate configurations are obtained for subsequent simulation and evaluation.

[0040] The specific steps of the synthesis of mining electric shovel types based on the screw theory will be described in more detail later and will not be repeated here.

[0041] The above-mentioned configuration design scheme based on screw theory provided in the embodiment of the present application can quickly and accurately provide a unified description of rigid body motion and constraints. Especially for the design of complex hybrid mechanisms, it can start from the essence of the dimension of the mechanism motion space and realize the conversion from motion diagram to mathematical description, making the configuration design process more systematic and scientific.

[0042] Step S120 , performing discrete element simulation on multiple electric mining shovels of the alternative configurations to respectively determine the dynamic excavation resistance of the electric mining shovels of the multiple alternative configurations.

[0043] Dynamic excavation resistance refers to the instantaneous resistance generated by friction, extrusion, and shear between ore particles and the bucket surface. It varies over time and is affected by factors such as bucket speed, angle, and material properties. Discrete element simulation allows for intuitive observation of particle flow at the bucket tooth tip and quantitative analysis of its stress state, providing input data and reference for subsequent dynamic simulations.

[0044] Discrete element simulation is a numerical calculation method based on particle models. It regards ore as an aggregate composed of a large number of discrete particles and simulates the interaction between them by setting the contact mechanical parameters between particles (such as elastic modulus, friction coefficient, restitution coefficient, etc.).

[0045] During discrete element simulation, each particle is treated as an independent rigid body, whose motion follows Newton's laws of motion. Contact detection and force calculation algorithms update the position and velocity of each particle. This approach accurately reflects the dynamic changes in materials during excavation and is particularly suitable for simulating discontinuous media, such as loose ores.

[0046] In actual implementation, to improve simulation accuracy, appropriate simulation parameters, such as particle size distribution, bulk density, and bucket motion trajectory, must be set based on actual operating conditions. Furthermore, detailed records of the bucket tooth tip's velocity and acceleration curves, as well as the excavation trajectory, are required to serve as boundary conditions in subsequent dynamic simulations. By comparing the dynamic excavation resistance of shovels of different configurations, we can provide a preliminary assessment of their energy consumption and efficiency in actual operations.

[0047] Step S130 , solving the dynamic models of multiple alternative configurations of mining electric shovels based on the dynamic excavation resistance, and determining the dynamic simulation results.

[0048] The dynamic excavation resistance obtained from the aforementioned discrete element simulation is used as an external load and fed into the dynamic model to determine the dynamic behavior of each candidate configuration during excavation. A dynamic model typically includes components such as the inertia matrix, the Coriolis force matrix, the gravity term, and control inputs. Numerical integration is used to solve the system's equations of motion. Dynamic simulations provide velocity and acceleration curves at the bucket tooth tip, as well as the excavation trajectory, allowing for evaluation of the kinematic continuity of each configuration.

[0049] Dynamic simulations are typically performed using multibody dynamics software such as ADAMS. This software supports dynamic modeling and simulation of complex mechanisms, handling a variety of factors such as nonlinear constraints, contact forces, and external loads. By combining discrete element simulation results with dynamic models, the dynamic performance of each configuration can be more comprehensively evaluated, providing reliable data support for subsequent configuration optimization.

[0050] Step S140 , determining a preferred configuration of the electric mining shovel based on the dynamic simulation results of multiple alternative configurations of the electric mining shovel and the motion continuity, singularity, and magnitude of the dynamic excavation resistance of the electric mining shovel.

[0051] The evaluation of motion continuity mainly focuses on the changing trends of the velocity curve and acceleration curve of the bucket tooth tip, such as whether the speed change of the bucket tooth tip is smooth. If there is a sudden change in speed, the motion continuity is considered to be poor.

[0052] Singularity analysis focuses on whether the mechanism has degree of freedom degradation at a specific position. For example, when the moving platform is in certain specific postures, it may lose one or more degrees of freedom, thereby causing uncontrollable motion behavior.

[0053] In practical applications, the kinematic characteristics of each configuration can be intuitively determined by plotting velocity and acceleration curves and excavation trajectory diagrams. Alternatively, as a possible implementation, quantitative analysis can be performed using mathematical tools such as the Lyapunov index and Jacobian matrix rank to determine the presence of singular states. Configurations with singular states should be excluded or structurally optimized. Ultimately, the optimal configuration is selected as the one with good motion continuity, no singular states, and low dynamic excavation resistance.

[0054] Step S150 , according to the multi-objective scale synthesis method, a parameterized model is established and boundary conditions are added to determine the multi-objective design function, and a genetic algorithm is used to combine structural parameters to complete the scale synthesis.

[0055] According to the optimal configuration, a multi-objective scale synthesis method is adopted to establish a parametric model including variables such as the length, width, thickness, installation angle, and position of each component of the configuration. The excavation depth, unloading height, and rotation angle required by the electric shovel in the actual working process are considered as boundary conditions. A multi-objective design function of the configuration is established based on the terminal trajectory of the moving platform, the workspace, and energy consumption. The genetic algorithm is used to combine the optimal structural parameters to obtain the optimal dimensional parameters and installation angle of the configuration, completing the optimal scale synthesis of the hybrid mechanism of the mining electric shovel working device.

[0056] A parametric model mathematically models the mechanical configuration using a set of controllable design variables. These variables can be adjusted to automatically generate different structural dimensions and assembly states. These variables are used as inputs, as "genes" referenced by the genetic algorithm and substituted into the kinematic model to calculate the end-point pose, trajectory, and workspace.

[0057] Boundary conditions refer to the maximum range of a parameter in the design process and are used to limit the search space for design variables. Examples include the maximum digging depth and minimum unloading height that an electric shovel must meet, and the maximum rotation angle of a rotating mechanism.

[0058] A multi-objective design function is a mathematical expression that simultaneously incorporates multiple design objectives into the design process, ultimately finding a balanced solution. Specifically, in some embodiments, the objective function includes minimizing the end trajectory error (making the end trajectory fit the logarithmic spiral excavation trajectory as closely as possible), maximizing the workspace (increasing the coverage range of the mechanism so that the electric shovel can adapt to more excavation postures), minimizing energy consumption (solving system energy consumption based on joint motion power consumption), etc.

[0059] Genetic algorithm is a global search method based on natural selection and genetic mechanism. It takes parameter variables as genes, objective functions as evaluation criteria, sets genetic generations, and performs genetic operations to obtain a set of optimal structural parameters and installation angle combinations that meet all constraints and have good multi-objective trade-offs, thereby completing the scale synthesis of the optimal configuration.

[0060] In summary, the mining shovel design method provided in the embodiment of the present application efficiently generates multiple alternative configurations based on screw theory, and evaluates the dynamic performance of each configuration through discrete element simulation and dynamics joint solution. Ultimately, the optimal configuration is determined based on motion continuity and singularity analysis. This configuration is then parametrically modeled, boundary conditions are set, a multi-objective design function is established, and a genetic algorithm is used to search for parameter combinations. Ultimately, the optimal structural parameters and installation position angle parameters of the configuration are obtained, completing the high-performance dimensional synthesis of the hybrid mechanism. This method not only improves the scientific nature and accuracy of the configuration design, but also effectively improves the operating efficiency and stability of the mining shovel under complex working conditions, realizing the integrated design of the mining shovel from configuration synthesis to dimensional parameters.

[0061] In some embodiments, as Figure 3 As shown, the aforementioned step S120, performing discrete element simulation on multiple alternative configurations of mining electric shovels to respectively determine the dynamic excavation resistance of the multiple alternative configurations of mining electric shovels, further includes steps S121-S124.

[0062] In step S121 , discrete element simulation models of multiple alternative configurations of mining electric shovels are respectively established.

[0063] Discrete element simulation models are used to recreate the interaction between the shovel and ore particles in a virtual computer environment. Because the structural forms of the aforementioned multiple alternative configurations differ, they require separate modeling. Specifically, for each alternative configuration, a simplified 3D model can be created in 3D modeling software and imported into discrete element simulation software (such as EDEM) to form a discrete element simulation model.

[0064] In step S122, an ore particle model is established in discrete element simulation software.

[0065] The ore particle model is a bulk mechanics model constructed in discrete element simulation software. Ore particles usually have irregular geometric shapes, different particle size distributions, and complex friction and collision characteristics, all of which will affect the simulation results.

[0066] To improve the accuracy of discrete element simulation results, the ore particle model can be configured based on the characteristics of the ore in the actual application environment of the mining shovel. For example, parameters such as the density, elastic modulus, and friction coefficient of the ore particle model can be determined through experimental testing, and the particle size distribution of the ore particles can be determined through stage-by-stage screening.

[0067] The contact forces acting on ore particles can be described using the soft sphere model in EDEM software, which allows for the calculation of interactions between particles or multiple particles. The contact models used between particles can be any of the following: Hertz-Mindlin (no slip), Hertz-Mindlin with Bonding, Hertz-Mindlin with JKR, Linear Cohesion, Linear Spring, Moving Plane, and Trio Charging.

[0068] By establishing the above-mentioned ore particle model, the mechanical response between electric shovels of different configurations and ore can be accurately predicted. At the same time, by establishing different types of particle models, the impact of different ore conditions on the performance of the electric shovel can be evaluated, thereby enhancing the adaptability of the design.

[0069] Figure 4 The figure shows a schematic diagram of discrete element simulation of a mining electric shovel; Figure 4 The ore particle model shown in FIG is a highly realistic particle model composed of spherical particles of different particle sizes.

[0070] In step S123 , driving functions are set for the plurality of discrete element simulation models in the discrete element simulation software.

[0071] The drive function is an external input signal applied to the shovel simulation model during discrete element simulation to simulate its actual motion. This drive function can be, for example, one or more of a displacement function, a velocity function, or an acceleration function. These functions determine the motion trajectory of the shovel's boom, arm, and bucket.

[0072] In step S124 , the dynamic excavation resistance of the mining electric shovel of each alternative configuration is solved using discrete element simulation software.

[0073] As mentioned earlier, dynamic excavation resistance is the instantaneous resistance generated by collision, friction, and shear between the bucket and the ore during the excavation process. This resistance varies over time and is affected by the shovel's configuration and the characteristics of the ore particles. By calculating the contact force and the sum of the contact forces between the bucket teeth and the ore particles, we can determine how this dynamic excavation resistance changes over time.

[0074] According to the above technical means, by establishing discrete element simulation models of multiple alternative configurations and constructing an ore particle model, the excavation process is simulated with precise drive function settings, and the dynamic excavation resistance is solved, the performance evaluation of the three-degree-of-freedom mining electric shovel configuration is realized, thereby improving the scientificity and rationality of the configuration optimization.

[0075] In some embodiments, as Figure 5 As shown, the aforementioned step S130, based on the dynamic excavation resistance, solves the dynamic models of multiple alternative configurations of mining electric shovels to determine the dynamic simulation results, further including steps S131-S133.

[0076] In step S131 , a dynamic simulation model of each alternative configuration of the mining electric shovel is established in the dynamic simulation software.

[0077] The dynamics simulation software may be, for example, Adams, which is widely used in the design and analysis of mechanical systems. It can simulate the motion behavior of complex mechanical systems through modeling and simulation to accurately calculate parameters such as the interaction force, velocity, and acceleration between components. Figure 6 This is an example of a dynamic simulation model provided in an embodiment of the present application.

[0078] In the technical solution of the embodiment of the present application, for each alternative configuration, a corresponding simulation model is established in the dynamics simulation software, and the connection relationship and constraint conditions between the components are set to generate a complete dynamics simulation model.

[0079] In step S132 , a driving function is set for each dynamic simulation model in the dynamic simulation software, and a corresponding dynamic excavation resistance is applied to each dynamic model.

[0080] The aforementioned drive function refers to the input signal set for the drive components in the model during the dynamics simulation process. For example, in a mining electric shovel, different drive functions can be set for the input ends of different branches to ensure that the bucket at the end moves according to a preset pattern. Furthermore, to more accurately simulate real-world working conditions, in this embodiment of the application, the dynamic digging resistance obtained using the discrete element simulation method is also applied as an external load to the bucket tooth tip during the dynamics simulation.

[0081] More specifically, in the aforementioned steps, discrete element simulation is completed in discrete element simulation software to obtain the resistance changes at different positions of the bucket during the excavation process. These resistance data are imported into the dynamic simulation software, and after aligning the time steps, they are applied to the corresponding positions frame by frame, thereby achieving high-fidelity simulation of the electric shovel mechanism during the actual working process.

[0082] In step S133, each dynamics simulation model is solved using dynamics simulation software to obtain dynamics simulation results for each candidate configuration.

[0083] The dynamic simulation results include velocity curves, acceleration curves, and excavation trajectories for multiple points on the bucket tooth tip. The velocity curve represents the rate of change of distance traveled by each point on the bucket tooth tip per unit time, reflecting the smoothness of the bucket's motion during excavation. The acceleration curve describes the rate of change of velocity at the bucket tooth tip per unit time. The excavation trajectory is the path of motion of the bucket tooth tip in three-dimensional space, reflecting the bucket's actual operating range and coverage capacity during excavation. By analyzing velocity, acceleration, and excavation trajectory, the continuity and stability of the mining shovel's motion during excavation can be intuitively determined, providing a scientific basis for configuration optimization and ensuring the selected solution has good engineering feasibility.

[0084] Using these technical approaches, a dynamic model of each candidate electric mining shovel configuration is established in dynamic simulation software, along with appropriate drive functions and dynamic excavation resistance. This allows for the velocity and acceleration curves, as well as the excavation trajectory, of each bucket tooth tip. This allows for an accurate assessment of the motion continuity and stability of each configuration in actual operation, enabling the selection of the optimal configuration and, consequently, improving the overall performance and efficiency of the electric mining shovel.

[0085] In some embodiments, determining a preferred configuration of the electric mining shovel based on the dynamic simulation results of the multiple alternative configurations of the electric mining shovel and the motion continuity and singularity of the electric mining shovel in step S140 further includes: If the dynamic simulation results of a first alternative configuration among multiple alternative configurations meet the following conditions, the first alternative configuration is determined to be the preferred configuration: the velocity curve corresponding to the first alternative configuration changes smoothly and has no inflection points; the acceleration curve corresponding to the first alternative configuration changes smoothly and has no infinitesimal or infinitesimal points. The first alternative configuration is one or more of the multiple alternative configurations.

[0086] In the technical solution of this application, the speed curve describes the speed of a certain point or component of a mining electric shovel over time during operation. If the speed curve changes smoothly, it means that the configuration moves smoothly during operation without sudden changes or violent fluctuations, which is conducive to improving operating efficiency and equipment stability. The inflection point refers to the point on the speed curve where the direction or slope changes significantly, usually indicating that the mechanism has discontinuous or singular motion at this location. If there is an inflection point in the speed curve, it may mean that the mechanism has limited movement or jamming in this area, affecting the overall operating performance.

[0087] The acceleration curve reflects the magnitude and trend of the rate of change of velocity. A smooth acceleration curve indicates that the mechanism transitions smoothly during acceleration or deceleration, without causing additional shock or vibration to the structure. The presence of infinite or infinitesimal points in the acceleration curve indicates that the mechanism may be at its limit or experiencing uncontrolled motion at certain moments. This phenomenon is often caused by improper mechanism configuration and can result in equipment damage or reduced efficiency.

[0088] By comprehensively analyzing the changing characteristics of the velocity and acceleration curves, the motion continuity and non-singularity of a mining shovel in a specific configuration can be effectively evaluated. Only when both types of curves exhibit good smoothness and stability is the configuration considered to have high engineering applicability and reliability, and thus to be the optimal configuration.

[0089] like Figure 7 As shown, in some embodiments, the aforementioned step S110, according to the motion characteristics and degree of freedom requirements of the mining electric shovel, performs type synthesis on the mining electric shovel based on the screw theory to determine multiple alternative configurations of the mining electric shovel, further includes steps S111-S116.

[0090] In step S111, according to the degrees of freedom and motion characteristics of the mining shovel and based on the screw theory, the motion screw coefficient of the moving platform of the mining shovel is determined.

[0091] Screw theory is a unified mathematical tool for describing the motion and mechanical behavior of rigid bodies in space. It represents the displacement and force system of a rigid body as six-dimensional vectors of motion screws and force screws, respectively, thereby achieving accurate modeling of the mechanism's motion degrees of freedom and force constraints. In configuration design, screw theory constructs the target motion screw system at the end of the task, infers the constraint screw system required to achieve the motion, and further maps it to the combination of kinematic pairs and branch structures, guiding the selection of kinematic pair types and branch configuration. It is an efficient design method that reversely derives the "structural composition" from the "functional goal." Compared with traditional configuration methods, screw theory is more suitable for spatial parallel mechanisms and hybrid systems, and has greater accuracy and controllability.

[0092] For example, in a 1R2T three-degree-of-freedom mining electric shovel, the moving platform usually has one rotational degree of freedom and two translational degrees of freedom, and the corresponding motion rotation system is:

[0093] In step S112, the constrained spinor system of the moving platform is determined according to the spinor reciprocity theory.

[0094] For example, in a 1R2T three-degree-of-freedom mining electric shovel, the corresponding constraint screw system is solved according to the dynamic platform motion screw system:

[0095] Screw reciprocity theory is a fundamental theory used to establish a one-to-one correspondence between a mechanism's motion space and its constraint space. Specifically, if the dimension of a mechanism's motion screw system is n, then the dimension of its corresponding constraint screw system must be 6-n. By representing the six degrees of freedom in space as screws and decomposing the mechanism space into a motion space and a constraint space, rapid and accurate conversion between motion degrees of freedom and constraints can be achieved.

[0096] Still Figure 8 Taking the spinor geometry shown in the figure as an example, based on the spinor reciprocity theory, we can get Figure 9 The constrained spinor system shown is represented.

[0097] Figure 9 As shown in 、 is a line vector, which means limiting the rotation along the axis. To constrain an even quantity, it means limiting the movement along the direction of the even quantity.

[0098] In step S113, the constrained twist system of each branch chain is determined according to the constrained twist system of the moving platform and the motion characteristics of the multiple branch chains of the mining electric shovel.

[0099] The branched constraint spinor system is a subset of the platform constraint spinor system decomposed from the platform constraint spinor system. Each branch provides a portion of the constraints that collectively act on the platform. By properly allocating the platform constraint spinor system, the sum of the independent constraints provided by each branch is guaranteed to be consistent with the overall mechanism.

[0100] For example, in the aforementioned 1R2T three-degree-of-freedom mining electric shovel, the constraint of the moving platform is the line vector 、 , even quantity .

[0101] According to the number of branches or the motion requirements of a specific branch, the constraint space of the moving platform is decomposed. The number of independent constraints in all the constraints provided by each branch should be consistent or equivalent to that of the moving platform. Taking into account redundant constraints, some situations can be included: (1) Two 6-DOF branches and one 1R2T branch (providing constraints 、 、 ); (2) One 6-DOF branch chain and two 1R2T branches (providing constraints 、 、 ); (3) Three 1R2T 3-DOF branches (providing constraints 、 、 ); (4) One 6-DOF branch chain, one 2R2T 4-DOF branch chain (providing constraints 、 or 、 ) and a 1R2T 3-DOF branched chain ( 、 、 ); (5) Two 2R2T 4-DOF branches (providing constraints 、 or 、 ) and a 1R2T 3-DOF branched chain (providing constraints 、 、 ); (6) Three 2R2T 4-DOF branches (providing constraints 、 or 、 , at least one branch constraint is different); (7) Two 2R3T 5-DOF branches (providing constraints or ) and a 2R2T 4-DOF branch chain (providing constraints 、 or 、 ); (8) Two 2R3T 5-DOF branches (providing constraints or , 2 branches provide different constraints) and 1 3R2T 5-DOF branch (providing constraints ).

[0102] In step S114, the kinematic spinor system of each branch is determined based on the constrained spinor system of each branch by using the spinor reciprocity theory.

[0103] After determining the constrained spinor system of each branch, the corresponding motion spinor system of each branch is calculated based on the spinor reciprocity theory. By expressing the motion spinor with geometric characteristics, the role of the branch in the mechanism can be more intuitively understood, and a basis can be provided for the subsequent design of kinematic pair combinations.

[0104] Taking the above cases (1), (2), and (3) as examples, since all three cases are provided with all the constraints of the moving platform by a branch chain, the motion rotation system of the branch chain and the moving platform is the same, that is:

[0105] In step S115 , multiple configurations of each branch are determined based on the rotational system of each branch.

[0106] According to the kinematic spinor system of each branch chain, the mathematical elements are converted into kinematic pair forms to realize the combination of the branch chain kinematic pairs.

[0107] The line vector is the revolute pair, and the pair is the translation pair. Considering the order of the kinematic pairs, different arrangements correspond to different branch configurations. Structural variants are formed under different arrangement orders or connection methods.

[0108] For example, for an RPR branch chain, its kinematic pairs can be arranged in the order of RPR, PRR or RRP. Different arrangement orders will affect the overall stiffness, accuracy and range of motion of the branch chain.

[0109] The motion pairs of each branch chain in the above cases (1), (2) and (3) are as follows: Figure 10 shown.

[0110] In step S116 , a plurality of candidate configurations of the mining electric shovel are determined based on the plurality of configurations of each branch chain.

[0111] After completing the configuration analysis of each branch chain, different branches can be combined according to the number and type of branches to form a complete mining shovel working device configuration. For example, a mechanism composed of three RPR branches can form a three-degree-of-freedom configuration; while a mechanism composed of two RSS branches and one UPU branch may achieve higher rigidity and stability.

[0112] According to the multiple configurations of each branch chain determined by the technical solution above, multiple branch chains are combined to obtain multiple alternative configurations of the mining electric shovel.

[0113] In some embodiments, see Figure 11 The aforementioned step S113, which determines the constrained spin system of each branch chain according to the motion characteristics of the dynamic platform constrained spin system and the multiple branches of the mining electric shovel, further includes steps S1131-S1133.

[0114] In step S1131 , the dimension of the moving platform constrained spinor system (constraint space) is determined according to the dimension of the moving platform motion spinor system (motion space).

[0115] Screw theory provides a way to transform motion forms into algebraic expressions, facilitating calculation and analysis. Through screw theory and dimensionality determination, the dimensions of the degree-of-freedom space and constraint space can be precisely defined. This eliminates the influence of redundant constraints, improving the accuracy of mechanism configuration design and optimizing the allocation of constraints between branches.

[0116] In step S1132, the moving platform constraint space is decomposed based on the number of branches and the kinematic characteristics of each branch, and the constraints of each branch are determined. The number of independent constraints provided by each branch is consistent with the dimension of the moving platform constraint spinor system.

[0117] After determining the dimensionality of the dynamic platform's constraint space, these constraints need to be rationally assigned to each branch. Each branch has different degrees of freedom and, therefore, provides different independent constraints. For example, a branch with three degrees of freedom provides three independent constraints, while a branch with six degrees of freedom provides no constraints. By decomposing the overall constraint space into branch-specific constraint subspaces and ensuring that the number of independent constraints provided by each branch matches the overall independent constraints, the branch constraints can be aligned with the overall system constraints, avoiding conflicting or duplicated constraints between branches.

[0118] In step S1133 , based on the constraints of each branch, the constrained spinor system (constraint space) of each branch is determined.

[0119] After assigning branch constraints, the branch's constrained spinor system is obtained. The branch constraint space is the space formed by the expansion of all the constrained spinors provided by the branch. This space of spinors not only describes the branch's constraint form (such as rotational constraints and translational constraints), but also clarifies its orientation and position in space. This reflects the branch's ability to constrain the moving platform, providing a basis for the subsequent solution of the branch's motion space and the selection of kinematic pairs.

[0120] According to the above technical means, the efficiency and accuracy of configuration design can be improved by decomposing the constraint space of the moving platform into the constraint subspaces of each branch and obtaining the corresponding motion space of the branch through spinor reciprocity.

[0121] In some embodiments, see Figure 12 The aforementioned step S116, determining the multiple configurations of each branch according to the multiple configurations of each branch, further includes steps S1161-S1164.

[0122] In step S1161, multiple configurations of each branch are determined according to different arrangement orders of multiple kinematic pairs of each branch.

[0123] Combining different types of kinematic pairs in different orders can generate branched structures with different kinematic properties. For example, a branched chain can form two different configurations by different arrangements of RPR and PRR.

[0124] Changing the arrangement order affects the kinematic characteristics and spatial layout of the branch chain. By varying the order of the kinematic pairs, branch chain functionality can be diversified without adding additional components. For example, the excavator arm branch chain of a mining shovel may adopt an RPR or PRP arrangement, corresponding to different end-effector postures and force transmission paths. By adjusting the order of the kinematic pairs, the spatial layout of the branch chain can be optimized.

[0125] In step S1162, multiple configurations of each branch chain in the multiple branch chains are combined to obtain multiple combined configurations of the mining electric shovel.

[0126] Since each branch chain can have multiple configurations, a large number of potential mechanism solutions can be generated by combining them. For example, in a three-degree-of-freedom mining electric shovel, if three branches are used, each with three configurations, a total of A combination configuration.

[0127] Figure 13 Schematic diagrams of several possible combination configurations of three-degree-of-freedom mining electric shovels are given.

[0128] In step S1163, the constrained spinor system of each branch is combined to determine the constrained spinor system provided by each branch in each combined configuration to the moving platform, and the dimension of the constrained spinor system corresponding to each combined configuration is determined to determine the degree of freedom of motion of each combined configuration.

[0129] By combining the constrained spinor systems of all branches and analyzing the dimension of the spinor system, the total number of constraints on the dynamic platform can be accurately calculated, and then its degrees of freedom can be derived to determine whether it meets the target motion requirements.

[0130] In step S1164, a combination configuration whose degree of freedom matches the degree of freedom requirement of the mining electric shovel among the multiple combination configurations is selected as an alternative configuration.

[0131] Degrees of freedom requirements refer to the type and number of degrees of freedom required to achieve the specific motion tasks a mining shovel must perform. For example, a three-degree-of-freedom shovel requires one rotation and two translations (1R2T) within the working plane.

[0132] When identifying candidate configurations, it is necessary to screen for combinations that provide precisely matched degrees of freedom. Only when a branched chain combination can provide the exact same degree of freedom required can it be considered a viable candidate, resulting in the aforementioned candidate configuration.

[0133] In some embodiments, see Figure 14 The aforementioned step S150, performing multi-objective scale synthesis on the preferred configuration, further includes steps S151-S155.

[0134] In step S151, based on the preferred configuration, constraints on the electric shovel during the actual excavation process are established.

[0135] Based on the results of the configuration design phase, the mechanism type is confirmed and the motion function indicators that the configuration needs to meet are extracted, such as the maximum digging depth (5m), maximum unloading height (9m), and maximum bucket rotation angle (110°), providing a basis for subsequent parameter modeling and objective function.

[0136] In step S152, key structural dimensions and kinematic pair installation parameters in the configuration are used as design variables to establish a parameterized model of the optimal configuration.

[0137] According to the structural type, design variables are defined, such as boom length, installation angle, installation hinge position, maximum component stroke, etc., and are uniformly defined as optimizable variables. A parametric model of the optimal configuration is established to lay the foundation for subsequent parameter design.

[0138] In step S153, boundary conditions and design constraints are introduced to establish a multi-objective design solution domain.

[0139] Taking into account the motion performance conditions, structural reliability conditions, and geometric constraints in actual excavation, they are used as boundary conditions and design constraints to form the solution domain and set a specific range for the parameters.

[0140] In step S154, a multi-objective design function of a better configuration is established based on the trajectory requirements, workspace requirements, and energy consumption requirements of the moving platform end.

[0141] Taking into account multiple performance objectives, the error between the end trajectory of the moving platform and the logarithmic spinor trajectory, the size of the workspace, the energy consumption, etc. are taken as targets, and a multi-objective design function of the optimal configuration is established to provide a judgment basis for solving the optimal parameters.

[0142] In step S155, a genetic algorithm is used to search for the optimal combination of structural dimensions and installation parameters within the solution domain to complete the multi-objective scale comprehensive design of the optimal configuration.

[0143] A genetic algorithm (GA) is used to search for the optimal design parameter combination in the parameter space. The design variables are used as chromosomes, the population is initialized and the operation parameters are set. The termination criterion is that the number of iterations in a fixed interval does not change significantly. A global search is performed and the optimized variable combination is extracted as the final structural size configuration to complete the scale synthesis of the optimal configuration.

[0144] The following combination Figure 15 The design method of the mining electric shovel provided in the embodiment of the present application is further explained.

[0145] This design method involves configuration synthesis and multi-objective scalar synthesis based on screw theory. Screw theory is used to solve the mechanism's motion space, and its digital representation is utilized to achieve efficient, rational, and standardized configuration design for mining shovels. A multi-objective scalar synthesis method is used to establish a parametric model including configuration parameter dimensions for the optional configuration. This model considers the boundary conditions and motion requirements during the excavation process, adds constraints, and constructs a multi-objective design function based on the end trajectory of the moving platform, the workspace, and energy consumption. A genetic algorithm is used for global search to obtain the component size configuration that meets the workspace requirements and minimizes energy consumption, thus achieving high-performance structural dimensional parameter design for the working device of the mining shovel.

[0146] Figure 15 The method includes steps S1601-S1621.

[0147] In step S1601, the degree of freedom characteristics are determined according to the motion requirements of the mining shovel.

[0148] According to the expected motion requirements of the electric shovel mechanism, the properties of the mechanism's degrees of freedom are determined, and the working requirements of the mechanism are clarified, that is, the specific motion form that the mechanism's end effector can achieve in space. Traditional mining electric shovels can only achieve 2T within the working plane. In order to improve the working flexibility of mining electric shovels, in the solution of the embodiment of this application, a rotational degree of freedom is added to the moving platform, that is, 1R2T three degrees of freedom within the working plane is achieved. Its specific motion form can be seen in Figure 2 .

[0149] In step S1602, the motion screw system of the mining electric shovel platform is solved according to the screw theory.

[0150] According to the degree of freedom of the mechanism, the screw theory is used to solve the motion screw system of the moving platform. The motion screw system constitutes the motion space of the moving platform. The rotating joints correspond to line vectors and the moving joints correspond to even quantities. For example, for a three-degree-of-freedom mining electric shovel with a degree of freedom of 1R2T, its motion screw system is:

[0151] In step S1603, the constrained spinor system of the moving platform is determined according to the spinor reciprocity theory.

[0152] The constraint screw system of the moving platform is solved by the screw reciprocity theory. The constraint screw system constitutes the constraint space of the moving platform. The line vector restricts the rotation along the line direction, and the even quantity restricts the movement along the even quantity direction. For a three-degree-of-freedom mining electric shovel with a degree of freedom of 1R2T, its constraint screw system is:

[0153] In step S1604, the independent constraint space of the moving platform is determined according to the dimension of the spinor system.

[0154] According to the dimension of the moving platform's constrained spinor system, the actual number of constraints imposed on the moving platform is determined, and the interrelated spinors in the constrained spinor system are removed. The dimension of the resulting simplified matrix is ​​the dimension of the constraint space.

[0155] In step S1605, the constraint space of the moving platform is decomposed.

[0156] According to the number of branches or the motion requirements of a specific branch, the constraint space of the moving platform is decomposed. The number of independent constraints among all the constraints provided by each branch should be consistent with or equivalent to the constraints of the moving platform.

[0157] In step S1606, constraints are assigned to each branch.

[0158] In the aforementioned 1R2T three-degree-of-freedom mining electric shovel, the constraint of the moving platform is the constraint couple , line vector 、 .

[0159] According to the number of branches or the motion requirements of a specific branch, the constraint space of the moving platform is decomposed. The number of independent constraints in all the constraints provided by each branch should be consistent or equivalent to that of the moving platform. Taking into account redundant constraints, some situations can be included: (1) Two 6-DOF branches and one 1R2T branch (providing constraints 、 、 ); (2) One 6-DOF branch chain and two 1R2T branches (providing constraints 、 、 ); (3) Three 1R2T 3-DOF branches (providing constraints 、 、 ); (4) One 6-DOF branch chain, one 2R2T 4-DOF branch chain (providing constraints 、 or 、 ) and a 1R2T 3-DOF branched chain ( 、 、 ); (5) Two 2R2T 4-DOF branches (providing constraints 、 or 、 ) and a 1R2T 3-DOF branched chain (providing constraints 、 、 ); (6) Three 2R2T 4-DOF branches (providing constraints 、 or 、 , at least one branch constraint is different); (7) Two 2R3T 5-DOF branches (providing constraints or ) and a 2R2T 4-DOF branch chain (providing constraints 、 or 、 ); (8) Two 2R3T 5-DOF branches (providing constraints or , 2 branches provide different constraints) and 1 3R2T 5-DOF branch (providing constraints ).

[0160] In step S1607, the constrained spinor system of each branch is solved according to the spinor theory.

[0161] In step S1608, the kinematic spinor system of each branch is solved according to the spinor reciprocity theory.

[0162] Taking the above cases (1), (2), and (3) as examples, since all the constraints of the moving platform are provided by a branch chain, the constraint space of the branch chain is consistent with the constraint space of the moving platform, which are:

[0163] In step S1609, branches are configured according to constraints and rationality, and the kinematic rotation of each branch is converted into a corresponding kinematic pair.

[0164] Based on the kinematic spinor system of each branch, and considering the rationality of the design, the line vectors or even quantities are converted into kinematic pairs to realize the combination of the branch kinematic pairs. The line vectors are the rotational pairs, and the even quantities are the translation pairs. Considering the order of the kinematic pairs, different arrangements correspond to different branch configurations.

[0165] In step S1610, the branches are combined into kinematic chains and hybrid structures. The selected branches are combined into hybrid structures, and the branch arrangement is reasonably selected according to mechanical principles.

[0166] In step S1611, the motion space of the hybrid mechanism is solved according to the screw theory to verify the motion characteristics of the hybrid mechanism. If the degree of freedom requirements are met, step S1612 is executed, otherwise return to step S1609.

[0167] As described above, by combining the constrained spinor systems of all branches and performing dimensional analysis, we can accurately calculate the total number of constraints imposed on the dynamic platform and, consequently, derive its degrees of freedom. If the derived degrees of freedom match the degrees of freedom requirement in step S1601, the hybrid configuration is determined to meet the degree of freedom requirement.

[0168] In step S1612, discrete mechanics and dynamics joint simulation is performed on the hybrid structure, and continuity is checked according to the velocity curve. If the continuity meets the requirements, step S1613 is executed, otherwise, the process returns to step S1609.

[0169] In step S1613, the singularity is verified according to the acceleration curve of the hybrid structure. If the singularity meets the requirements, step S1614 is executed; otherwise, the process returns to step S1609.

[0170] After completing the configuration synthesis of the three-degree-of-freedom mining shovel working device, the new configuration electric shovel needs to be dynamically verified. Due to the large number of configurations, the workload of dynamic solution through numerical calculation methods is large. In addition, the electric shovel working device will be subject to variable excavation resistance from the material surface during excavation. Therefore, considering the mechanics of bulk materials, an ore particle model is established in Edem. By building a simplified three-dimensional model of the new configuration and importing it into Adams for configuration, and setting relevant drive functions, the dynamic model is combined with the discrete element model. The dynamic excavation resistance feedback from the discrete element model can achieve an accurate solution of the dynamic model. Based on the velocity curve, acceleration curve, and excavation trajectory of each point at the bucket tooth tip, the motion continuity of the new configuration mining shovel can be determined. If the velocity curve changes smoothly without inflection points, and the acceleration curve changes smoothly without infinity or infinitesimal, it indicates that the new configuration has motion continuity within the range of motion.

[0171] In step S1614, the configuration synthesis of the hybrid mining electric shovel is completed.

[0172] In step S1615, based on the optimal configuration, constraints on the electric shovel during the actual excavation process are established.

[0173] In step S1616, the key structural dimensions, kinematic pair installation positions and angle parameters in the configuration are used as design variables to establish a parametric model of the optimal configuration.

[0174] In step S1617, boundary conditions and design constraints are introduced to establish a multi-objective parameter design solution domain.

[0175] In step S1618, a multi-objective design function of the configuration is established based on the end trajectory of the moving platform, the workspace and the energy consumption.

[0176] In step S1619, a genetic algorithm is used to search for the optimal combination of structural dimensions and installation parameters within the solution domain.

[0177] In step S1620, a multi-objective scale comprehensive design of a new configuration of a hybrid mining electric shovel is completed.

[0178] Combined with the above Figures 1-15 The method embodiment of the present application is described in detail. Figure 16 Introducing the device embodiment of the present application, it should be understood that the description of the device embodiment corresponds to the method embodiment. Therefore, for parts that are not described in detail, reference can be made to the method embodiment above.

[0179] Figure 16 This is a schematic structural diagram of a design device for a mining electric shovel provided in an embodiment of the present application. Figure 16 The design device 1600 includes: The first determining unit 1610 is configured to perform type synthesis on the electric mining shovel based on the screw theory according to the motion characteristics and degree of freedom requirements of the electric mining shovel, and determine multiple candidate configurations of the electric mining shovel.

[0180] The discrete element simulation unit 1620 is configured to perform discrete element simulation on the multiple electric mining shovels of the alternative configurations, and respectively determine the dynamic excavation resistance of the electric mining shovels of the multiple alternative configurations.

[0181] The dynamics simulation unit 1630 is configured to solve the dynamics models of the mining electric shovels of the plurality of alternative configurations according to the dynamic excavation resistance, and determine a dynamics simulation result.

[0182] The second determining unit 1640 is configured to determine a preferred configuration of the electric mining shovel based on the dynamic simulation results of the multiple alternative configurations of the electric mining shovel and the motion continuity, singularity, and magnitude of the dynamic excavation resistance of the electric mining shovel.

[0183] The scale synthesis unit 1650 is used to establish a parameterized model, boundary conditions and multi-objective design function of the preferred configuration according to a multi-objective scale synthesis method, so as to perform multi-objective scale synthesis on the preferred configuration.

[0184] In some embodiments, the discrete element simulation unit 1620 is also used to: establish discrete element simulation models of the multiple alternative configurations of mining electric shovels respectively; establish an ore particle model in the discrete element simulation software; set driving functions for the multiple discrete element simulation models in the discrete element simulation software respectively; and use the discrete element simulation software to solve the dynamic excavation resistance of each of the alternative configurations of the mining electric shovel.

[0185] In some embodiments, the dynamic simulation unit 1630 is also used to: establish a dynamic simulation model of each of the alternative configurations of the mining electric shovel in the dynamic simulation software; set a driving function for each of the dynamic simulation models in the dynamic simulation software, and apply corresponding dynamic excavation resistance to each of the dynamic models; use the dynamic simulation software to solve each of the dynamic simulation models to obtain the dynamic simulation results of each of the alternative configurations; the dynamic simulation results include velocity curves, acceleration curves and excavation trajectories of multiple points on the bucket tooth tip.

[0186] In some embodiments, determining the optimal configuration of the mining electric shovel based on the motion continuity and singularity of the mining electric shovel includes: determining that the first alternative configuration is the optimal configuration when the dynamic simulation result of the first alternative configuration among the multiple alternative configurations meets the following conditions: the speed curve corresponding to the first alternative configuration changes smoothly and does not have an inflection point; the acceleration curve corresponding to the first alternative configuration changes smoothly, and the acceleration curve does not have an infinite or infinitesimal point.

[0187] In some embodiments, the first determination unit is further used to: determine the motion spin system of the moving platform of the mining electric shovel based on the spin theory according to the degrees of freedom and motion characteristics of the mining electric shovel; determine the constrained spin system of the moving platform according to the spin reciprocity theory; determine the constrained spin system of each branch according to the constrained spin system of the moving platform and the motion characteristics of the multiple branches of the mining electric shovel; determine the motion spin system of each branch through the spin reciprocity theory according to the constrained spin system of each branch; determine multiple configurations of each branch according to the motion spin system of each branch; determine multiple alternative configurations of the mining electric shovel according to the multiple configurations of each branch.

[0188] In some embodiments, the constrained spinor system of each branch is determined based on the motion characteristics of the constrained spinor system of the moving platform and the multiple branches of the mining electric shovel, including: determining the dimension of the constrained spinor system of the moving platform based on the dimension of the motion spinor system of the moving platform; decomposing the constrained spinor system of the moving platform based on the number of multiple branches and the motion characteristics of each branch to determine the constraint condition of each branch; determining the constrained spinor system of each branch based on the constraint condition of each branch; wherein the number of independent constraints among all the constraints provided by each branch is consistent with the dimension of the constrained spinor system of the moving platform.

[0189] In some embodiments, the multiple alternative configurations of the mining electric shovel are determined based on the multiple configurations of each branch chain, including: determining the multiple configurations of each branch chain based on the different arrangement orders of the multiple motion pairs of each branch chain; combining the multiple configurations of each branch chain in the multiple branches to obtain multiple combined configurations of the mining electric shovel; combining the constrained spinor system of each branch chain to determine the constrained spinor system provided to the moving platform by each branch chain in each combined configuration, determining the dimension of the constrained spinor system corresponding to each combined configuration to determine the degree of freedom of motion of each combined configuration; and taking the combined configuration whose degree of freedom in the multiple combined configurations matches the degree of freedom requirement of the mining electric shovel as the alternative configuration.

[0190] In some embodiments, the scale synthesis unit 1650 is also used to: establish the constraint conditions of the mining electric shovel during the excavation process based on the preferred configuration; use the structural dimensions and kinematic pair installation parameters in the preferred configuration as design variables to establish a parametric model of the optimal configuration; introduce boundary conditions and design constraints to establish a multi-objective design solution domain; establish a multi-objective design function of the preferred configuration based on the end trajectory requirements, workspace requirements and energy consumption requirements of the moving platform of the mining electric shovel; use a genetic algorithm to search for the optimal combination of the structural dimensions and the installation parameters in the multi-objective design solution domain to complete the multi-objective scale synthesis design of the preferred configuration.

[0191] Figure 17 is a schematic structural diagram of an electronic device provided in an embodiment of the present application, Figure 17 The electronic device 1700 is used to implement the design method described in the above method embodiment.

[0192] The electronic device 1700 may include one or more processors 1710. The processor 1710 may support the electronic device 1700 in implementing the methods described in the above method embodiments. The processor 1710 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor 1710 may be another 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, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0193] The electronic device 1700 may further include one or more memories 1720. The memories 1720 store programs that can be executed by the processor 1710, causing the processor 1710 to perform the methods described in the above method embodiments. The memories 1720 may be independent of the processor 1710 or integrated into the processor 1710.

[0194] The embodiments of the present application also provide a computer-readable storage medium having executable code stored thereon. When the executable code is executed, the methods in the various embodiments of the present application can be implemented.

[0195] The present application also provides a computer program product, which includes a program that enables a computer to execute the methods in various embodiments of the present application.

[0196] The present application also provides a computer program that enables a computer to execute the methods in the various embodiments of the present application.

[0197] It should be understood that in the embodiments of the present application, "B corresponding to A" means that B is associated with A and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B based solely on A, but B can also be determined based on A and / or other information.

[0198] It should be understood that the term "and / or" in this document simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0199] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean 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 of the present application.

[0200] In the several embodiments provided in this application, it should be understood that the disclosed systems and devices can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components 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 through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0201] The units described as separate components may or may not be physically separate, and 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 these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0202] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0203] In the above embodiments, all or part of the embodiments can be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any computer-readable medium or a data storage device such as a server or data center that integrates one or more computer-readable media. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital versatile disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0204] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A design method for a hybrid mining electric shovel, characterized in that: The method comprises: According to the motion characteristics and degree of freedom requirements of the mining electric shovel, the mining electric shovel is subjected to type synthesis based on the screw theory to determine multiple alternative configurations of the mining electric shovel; Performing discrete element simulation on the multiple electric mining shovels of the alternative configurations to respectively determine the dynamic excavation resistance of the electric mining shovels of the multiple alternative configurations; Solving the dynamic models of the mining electric shovels of the multiple alternative configurations based on the dynamic excavation resistance to determine dynamic simulation results; Determining a preferred configuration of the electric mining shovel based on the dynamic simulation results of the multiple alternative configurations of the electric mining shovel and on the motion continuity and singularity of the electric mining shovel and the magnitude of the dynamic excavation resistance; According to the multi-objective scale synthesis method, a parameterized model, boundary conditions and multi-objective design function of the preferred configuration are established to perform multi-objective scale synthesis on the preferred configuration.

2. The method according to claim 1, characterized in that The performing discrete element simulation on the multiple alternative configurations of the electric mining shovels to respectively determine the dynamic excavation resistance of the multiple alternative configurations of the electric mining shovels includes: Establishing discrete element simulation models of the mining electric shovels of the multiple alternative configurations respectively; Establish an ore particle model in discrete element simulation software; Setting driving functions for the plurality of discrete element simulation models in the discrete element simulation software respectively; The discrete element simulation software is used to solve the dynamic excavation resistance of the mining electric shovel of each alternative configuration.

3. The method according to claim 2, characterized in that Solving the dynamic models of the mining electric shovels of the multiple alternative configurations based on the dynamic excavation resistance and determining the dynamic simulation results includes: Establishing a dynamic simulation model of each of the alternative configurations of the mining electric shovel in dynamic simulation software; Setting a driving function for each of the dynamic simulation models in the dynamic simulation software, and applying a corresponding dynamic excavation resistance to each of the dynamic models; The dynamic simulation software is used to solve each of the dynamic simulation models to obtain a dynamic simulation result of each of the alternative configurations; the dynamic simulation result includes a velocity curve, an acceleration curve, and an excavation trajectory of multiple points on the bucket tooth tip.

4. The method according to claim 3, characterized in that The determining of a preferred configuration of the electric mining shovel based on the motion continuity and singularity of the electric mining shovel comprises: When the dynamics simulation results of a first alternative configuration among the multiple alternative configurations meet the following conditions, the first alternative configuration is determined to be the preferred configuration: The speed curve corresponding to the first alternative configuration changes smoothly and has no inflection point; The acceleration curve corresponding to the first alternative configuration changes smoothly, and the acceleration curve does not have an infinite or infinitesimal point.

5. The method according to any one of claims 1 to 4, characterized in that According to the motion characteristics and degree of freedom requirements of the mining electric shovel, the mining electric shovel is subjected to type synthesis based on the screw theory to determine multiple alternative configurations of the mining electric shovel, including: According to the degrees of freedom and motion characteristics of the mining electric shovel and based on the screw theory, the motion screw system of the moving platform of the mining electric shovel is determined; According to the spinor reciprocity theory, determining the constrained spinor system of the moving platform; Determining a constrained spin system for each branch chain according to the motion characteristics of the dynamic platform constrained spin system and the multiple branch chains of the mining electric shovel; Determine the motion spinor system of each branch chain according to the constrained spinor system of each branch chain by using the spinor reciprocity theory; determining a plurality of configurations of each of the branches according to a rotational system of motion of each of the branches; According to the multiple configurations of each branch chain, multiple candidate configurations of the mining electric shovel are determined.

6. The method according to claim 5, characterized in that The step of determining the constrained spin system of each branch chain according to the motion characteristics of the dynamic platform constrained spin system and the multiple branch chains of the mining electric shovel comprises: Determining the dimension of the constrained spinor system of the moving platform according to the dimension of the motion spinor system of the moving platform; Decomposing the constrained spinor system of the moving platform according to the number of the multiple branches and the motion characteristics of each branch, and determining the constraint condition of each branch; Determining a constrained spinor system of each branch chain according to the constraint condition of each branch chain; The number of independent constraints among all the constraints provided by each branch chain is consistent with the dimension of the constrained spinor system of the moving platform.

7. The method according to claim 5, characterized in that Determining multiple alternative configurations of the mining electric shovel based on the multiple configurations of each branch chain includes: Determining multiple configurations of each branch chain according to different arrangement orders of multiple kinematic pairs of each branch chain; Combining multiple configurations of each branch chain in the multiple branch chains to obtain multiple combined configurations of the mining electric shovel; Combining the constrained spinor system of each branch chain to determine the constrained spinor system provided by each branch chain in each combined configuration to the moving platform, and determining the dimension of the constrained spinor system corresponding to each combined configuration to determine the degree of freedom of motion of each combined configuration; A combination configuration whose degree of freedom among the multiple combination configurations matches the degree of freedom requirement of the mining electric shovel is used as the alternative configuration.

8. The method according to any one of claims 1 to 4, characterized in that The multi-objective scale synthesis of the preferred configuration includes: According to the preferred configuration, establishing constraint conditions for the mining electric shovel during the excavation process; The structural dimensions and kinematic pair installation parameters of the preferred configuration are used as design variables to establish a parameterized model of the optimal configuration; Introduce boundary conditions and design constraints to establish a multi-objective design solution domain; Based on the requirements of the end trajectory of the moving platform, the working space and the energy consumption of the mining electric shovel, a multi-objective design function of the optimal configuration is established; By using a genetic algorithm, the optimal combination of the structural dimensions and the installation parameters is searched within the multi-objective design solution domain, and the multi-objective scale comprehensive design of the preferred configuration is completed.

9. A design device for a mining electric shovel, characterized in that: The device comprises: a first determining unit, configured to perform type synthesis on the electric mining shovel based on the screw theory according to the motion characteristics and degree of freedom requirements of the electric mining shovel, and determine a plurality of alternative configurations of the electric mining shovel; a discrete element simulation unit, configured to perform discrete element simulation on the multiple electric mining shovels of the alternative configurations, and respectively determine the dynamic excavation resistance of the electric mining shovels of the multiple alternative configurations; a dynamics simulation unit, configured to solve the dynamics models of the mining electric shovels of the plurality of alternative configurations according to the dynamic excavation resistance, and determine a dynamics simulation result; a second determining unit configured to determine a preferred configuration of the electric mining shovel based on the dynamic simulation results of the multiple alternative configurations of the electric mining shovel and on the motion continuity and singularity of the electric mining shovel and the magnitude of the dynamic excavation resistance; The scale synthesis unit is used to establish a parameterized model, boundary conditions and multi-objective design function of the preferred configuration according to a multi-objective scale synthesis method, so as to perform multi-objective scale synthesis on the preferred configuration.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium is used to store a computer program, and the computer program performs the method according to any one of claims 1 to 8 when executed.

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