Robot rigid-flexible coupling model construction method and device, equipment and storage medium

Abstract

The application discloses a robot rigid-flexible coupling model construction method, device and equipment and a storage medium, and comprises the following steps: establishing a three-dimensional model of a robot, and establishing an initial rigid body dynamics model of the robot based on the three-dimensional model; adjusting the format of the three-dimensional model into a target format, and performing modal simulation on the three-dimensional model in the target format; generating a flexible body corresponding to a connecting rod of the robot according to a simulation result of the modal simulation, replacing a corresponding rigid body in the initial rigid body dynamics model with the flexible body, and generating a rigid-flexible coupling model containing the flexibility of the connecting rod; establishing a flexible joint module corresponding to a joint of the robot, incorporating the flexible joint module into the rigid-flexible coupling model containing the flexibility of the connecting rod, and generating a rigid-flexible coupling model corresponding to the robot. The rigid-flexible coupling model constructed by the application can not only reproduce the dynamic characteristics of the robot under different working conditions, but also accurately give the joint torque and rotation angle of the robot, and can improve the accuracy of the motion state simulation of the industrial robot.

Description

Technical Field

[0001] This invention relates to the field of multibody dynamics simulation analysis technology, and in particular to a method, apparatus, device and storage medium for constructing a rigid-flexible coupling model of a robot. Background Technology

[0002] Industrial robots are developing towards high speed, heavy load, high precision, and lightweight. In the past, when analyzing the dynamic characteristics of robot systems, components were often treated as rigid bodies when building models. This made it impossible to accurately simulate the real motion state of industrial robots under high-speed and heavy-load conditions. Therefore, how to improve the accuracy of industrial robot motion state simulation has become an urgent technical problem to be solved. Summary of the Invention

[0003] The main objective of this invention is to provide a method, apparatus, device, and storage medium for constructing a rigid-flexible coupling model of a robot, aiming to solve the technical problem of low accuracy in simulating the motion state of industrial robots in the prior art.

[0004] To achieve the above objectives, the present invention provides a method for constructing a rigid-flexible coupling model of a robot, the method comprising the following steps:

[0005] Establish a three-dimensional model of the robot, and establish an initial rigid body dynamics model of the robot based on the three-dimensional model;

[0006] The format of the 3D model is adjusted to the target format, and modal simulation is performed on the 3D model in the target format.

[0007] Based on the simulation results of modal simulation, a flexible body corresponding to the link of the robot is generated, and the corresponding rigid body in the initial rigid body dynamics model is replaced with the flexible body to generate a rigid-flexible coupling model with link flexibility.

[0008] A flexible joint module corresponding to the joint of the robot is established, and the flexible joint module is incorporated into the rigid-flexible coupling model containing flexible links to generate a rigid-flexible coupling model corresponding to the robot.

[0009] Optionally, the step of establishing a three-dimensional model of the robot and establishing an initial rigid body dynamics model of the robot based on the three-dimensional model includes:

[0010] A 3D model of the robot is created using 3D modeling software, and the parameters of the 3D model are configured according to the parameters of the robot.

[0011] Export the 3D model after parameter configuration as an Extensible Markup Language (Extreme Markup Language) format;

[0012] The initial rigid body dynamics model of the robot is generated according to the Extensible Markup Language (EXPLAIN) format.

[0013] Optionally, adjusting the format of the 3D model to the target format and performing modal simulation on the 3D model in the target format includes:

[0014] Adjust the format of the 3D model to the target format, and import the 3D model in the target format into the finite element analysis software;

[0015] The finite element analysis software is used to set the model parameters of the target format three-dimensional model. The model parameter settings include mesh generation, material property configuration, and adding flexible multi-point constrained joints.

[0016] Perform modal simulation on the model after configuring the model parameters to generate the first simulation result;

[0017] The flexible multi-point constrained joint was modified into a rigid multi-point constrained joint, and modal simulation was performed on the modified model to generate a second simulation result.

[0018] Optionally, performing modal simulation on the model after configuring its model parameters to generate a first simulation result includes:

[0019] Modal simulation is performed on the model after the model parameters are configured. The connection relationship between the flexible component and other components is adjusted according to the modal array and modal frequency generated by the modal simulation.

[0020] Modal simulation was performed on the model after the connection relationships were adjusted;

[0021] If the modal array and modal frequencies generated after simulation meet the preset conditions, the first simulation result is generated.

[0022] Optionally, the step of generating a flexible body corresponding to the robot's link based on the simulation results of modal simulation, and replacing the corresponding rigid body in the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing link flexibility, includes:

[0023] If the first simulation result is consistent with the second simulation result, the component to be made flexible is derived.

[0024] The finite element analysis software is used to mesh the component to be made flexible, and the INP file of the component to be made flexible is exported.

[0025] Convert the INP file into a text file and import the text file into the target software;

[0026] The target software performs modal reduction on the component to be softened based on the text file, generating reduced-order model data.

[0027] Generate a flexible body corresponding to the component to be softened based on the reduced-order model data;

[0028] The rigid body in the initial rigid body dynamics model is replaced with the flexible body to generate a rigid-flexible coupling model with flexible linkage.

[0029] Optionally, the step of performing modal reduction on the component to be softened using the target software based on the text file to generate reduced-order model data includes:

[0030] The target software extracts mesh information from the text file and establishes a geometric solid model of the component to be softened based on the extracted mesh information.

[0031] The target software is used to perform modal order reduction on the geometric solid model to be reduced, generating an equivalent stiffness matrix and an equivalent mass matrix;

[0032] A damping matrix is ​​generated based on the equivalent stiffness matrix and the equivalent mass matrix;

[0033] Reduced-order model data is generated based on the equivalent stiffness matrix, the equivalent mass matrix, and the damping matrix.

[0034] Optionally, the step of establishing flexible joint modules corresponding to the robot's joints and incorporating the flexible joint modules into the rigid-flexible coupling model containing flexible links to generate a rigid-flexible coupling model corresponding to the robot includes:

[0035] Create functional modules and rotary joint modules using the target software;

[0036] Based on historical and current input data, the module input and module output of the functional module are determined, and a flexible joint module is generated.

[0037] The torque output by the rotary joint module in the rigid-flexible coupling model with connecting rod flexibility is used as the input of the flexible joint module;

[0038] The output of the flexible joint module is used as the input of the universal joint module, and the internal mechanical properties and excitation mode of the universal joint module are adjusted to generate a rigid-flexible coupling model corresponding to the robot.

[0039] Furthermore, to achieve the above objectives, the present invention also proposes a robot rigid-flexible coupling model construction device, the device comprising:

[0040] The model building module is used to build a three-dimensional model of the robot and, based on the three-dimensional model, to build an initial rigid body dynamics model of the robot.

[0041] The modal simulation module is used to adjust the format of the 3D model to the target format and perform modal simulation on the 3D model in the target format.

[0042] The generation module is used to generate the flexible body corresponding to the link of the robot based on the simulation results of the modal simulation, and replace the rigid body corresponding to the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing the link flexibility.

[0043] The rigid-flexible coupling model establishment module is used to establish the flexible joint module corresponding to the joint of the robot, and to incorporate the flexible joint module into the rigid-flexible coupling model containing the linkage flexibility to generate a rigid-flexible coupling model corresponding to the robot.

[0044] Furthermore, to achieve the above objectives, the present invention also proposes a robot rigid-flexible coupling model construction device, the device comprising: a memory, a processor, and a robot rigid-flexible coupling model construction program stored in the memory and executable on the processor, the robot rigid-flexible coupling model construction program being configured to implement the steps of the robot rigid-flexible coupling model construction method described above.

[0045] Furthermore, to achieve the above objectives, the present invention also proposes a storage medium storing a robot rigid-flexible coupling model construction program, wherein when the robot rigid-flexible coupling model construction program is executed by a processor, the steps of the robot rigid-flexible coupling model construction method described above are implemented.

[0046] This invention establishes a 3D model of a robot and, based on this 3D model, establishes an initial rigid-body dynamics model of the robot. The format of the 3D model is adjusted to a target format, and modal simulation is performed on the target format 3D model. Based on the simulation results of the modal simulation, flexible bodies corresponding to the robot's links are generated, and the corresponding rigid bodies in the initial rigid-body dynamics model are replaced with these flexible bodies, generating a rigid-flexible coupling model containing link flexibility. Flexible joint modules corresponding to the robot's joints are established and incorporated into the rigid-flexible coupling model containing link flexibility, generating a rigid-flexible coupling model corresponding to the robot. This invention comprehensively considers the influence of link flexibility and joint flexibility on the robot's dynamics model. The constructed rigid-flexible coupling model can not only reproduce the dynamic characteristics of the robot under different working conditions but also accurately provide the robot's joint torques and rotation angles, thereby improving the accuracy of industrial robot motion state simulation. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the structure of the robot rigid-flexible coupling model construction device for the hardware operating environment involved in the embodiments of the present invention;

[0048] Figure 2This is a flowchart illustrating the first embodiment of the robot rigid-flexible coupling model construction method of the present invention;

[0049] Figure 3 This is a flowchart illustrating the second embodiment of the robot rigid-flexible coupling model construction method of the present invention;

[0050] Figure 4 This is a flowchart illustrating the third embodiment of the robot rigid-flexible coupling model construction method of the present invention;

[0051] Figure 5 This is a structural block diagram of the first embodiment of the robot rigid-flexible coupling model construction device of the present invention.

[0052] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0053] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0054] Reference Figure 1 , Figure 1 This is a schematic diagram of the robot rigid-flexible coupling model construction device for the hardware operating environment involved in the embodiments of the present invention.

[0055] like Figure 1 As shown, the robot rigid-flexible coupling model building device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be high-speed random access memory (RAM) or stable non-volatile memory (NVM), such as a disk storage device. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0056] Those skilled in the art will understand that Figure 1The structure shown does not constitute a limitation on the device for building a rigid-flexible coupled robot model, and may include more or fewer parts than shown, or combine certain parts, or have different arrangements of parts.

[0057] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a robot rigid-flexible coupling model construction program.

[0058] exist Figure 1 In the robot rigid-flexible coupling model building device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 can be set in the robot rigid-flexible coupling model building device. The robot rigid-flexible coupling model building device calls the robot rigid-flexible coupling model building program stored in the memory 1005 through the processor 1001 and executes the robot rigid-flexible coupling model building method provided in the embodiment of the present invention.

[0059] This invention provides a method for constructing a rigid-flexible coupling model of a robot, referring to... Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the robot rigid-flexible coupling model construction method of the present invention.

[0060] In this embodiment, the method for constructing the robot rigid-flexible coupling model includes the following steps:

[0061] Step S10: Establish a three-dimensional model of the robot, and establish an initial rigid body dynamics model of the robot based on the three-dimensional model.

[0062] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, or an electronic device or a robot rigid-flexible coupling model building device capable of performing the above functions. The following uses a robot rigid-flexible coupling model building device (hereinafter referred to as the building device) as an example to illustrate this embodiment and the following embodiments.

[0063] It is understandable that a 3D model of the robot is created in 3D modeling software; the initial rigid body dynamics model can be a rigid body dynamics model built based on the 3D model without link flexibility and joint flexibility.

[0064] Step S20: Adjust the format of the three-dimensional model to the target format, and perform modal simulation on the three-dimensional model in the target format.

[0065] Understandably, the target format can be a proprietary format of the Space Claim software, such as the SCDOC format; the 3D model in the target format is then imported into the Geometry module of ANSYS Workbench for modal simulation.

[0066] Step S30: Generate the flexible body corresponding to the link of the robot based on the simulation results of the modal simulation, and replace the rigid body corresponding to the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing the link flexibility.

[0067] It is understandable that a rigid body dynamics model with flexible links can be a dynamics model generated by making the links in the initial rigid body dynamics model more flexible.

[0068] Step S40: Establish flexible joint modules corresponding to the joints of the robot, and incorporate the flexible joint modules into the rigid-flexible coupling model containing flexible links to generate a rigid-flexible coupling model corresponding to the robot.

[0069] In the specific implementation, a 3D model of the robot is established, the material properties of each component are configured, and the XML file of the 3D model is exported. A dynamic model is generated in Simulink using MATLAB based on the XML file of the 3D model. The motion constraints of the dynamic model are adjusted to generate an initial rigid body dynamic model. The format of the robot's 3D model is adjusted to the target format, and the target format 3D model is imported into finite element software for modal simulation. The mesh of the link to be flexible is exported, and a solid is generated from the mesh. The material properties of the link to be flexible are configured, and the corresponding stiffness and mass matrices are generated. The Craig-Bampton method is used for modal order reduction to generate equivalent stiffness and mass matrices. The equivalent stiffness and mass matrices are then imported into Simulink's Flexible module. In the Solid module, a flexible body corresponding to the link to be made flexible is generated. The link to be made flexible is replaced with this flexible body to generate a rigid-flexible coupling model containing the link's flexibility. By adding a degree of freedom and using the Preisach model to characterize the flexibility and hysteresis characteristics of the robot joint, a flexible joint module is built in Simulink using the MATLAB Function module. The flexible joint module is then incorporated into the rigid-flexible coupling model containing the link's flexibility to generate the rigid-flexible coupling model corresponding to the robot.

[0070] Furthermore, in order to construct the initial rigid body dynamics model corresponding to the robot, step S10 includes: establishing a three-dimensional model of the robot using three-dimensional modeling software, and configuring the parameters of the three-dimensional model according to the parameters of the robot; exporting the parameter-configured three-dimensional model into an Extensible Markup Language (XML) format; and generating the initial rigid body dynamics model of the robot according to the XML format.

[0071] Understandably, parameter configuration includes configuring the robot's material properties and kinematic constraints; in Extensible Markup Language (XML) and XML formats.

[0072] In practice, a 3D model of the robot is created in 3D modeling software, and the robot's material properties and kinematic constraints are configured. The 3D model of the robot is exported as an XML file using the toolkit of the 3D modeling software. MATLAB reads the XML file of the robot's 3D model and generates the robot's dynamic model. Based on the robot's actual motion constraints, the joints of the initial rigid body dynamic model are modified. The motion joints use the Gimbal Joint module. The internal mechanical properties of the X and Y axes in the Gimbal Joint module are adjusted. The stiffness of the module is set according to the robot's actual joint connection stiffness. The excitation mode of the Z axis (robot joint rotation axis) in the Gimbal Joint module is adjusted, with the torque set to automatic calculation and the motion set to external input, thus generating the robot's initial rigid body dynamic model.

[0073] This embodiment establishes a 3D model of the robot and, based on this 3D model, establishes an initial rigid-body dynamics model of the robot. The format of the 3D model is adjusted to a target format, and modal simulation is performed on the target format 3D model. Based on the simulation results of the modal simulation, flexible bodies corresponding to the robot's links are generated, and the corresponding rigid bodies in the initial rigid-body dynamics model are replaced with these flexible bodies, generating a rigid-flexible coupling model containing link flexibility. Flexible joint modules corresponding to the robot's joints are established, and these flexible joint modules are incorporated into the rigid-flexible coupling model containing link flexibility, generating a rigid-flexible coupling model corresponding to the robot. This embodiment comprehensively considers the influence of link flexibility and joint flexibility on the robot's dynamics model. The constructed rigid-flexible coupling model can not only reproduce the dynamic characteristics of the robot under different working conditions but also accurately provide the robot's joint torques and rotation angles, thereby improving the accuracy of industrial robot motion state simulation.

[0074] refer to Figure 3 , Figure 3 This is a flowchart illustrating the second embodiment of the robot rigid-flexible coupling model construction method of the present invention.

[0075] Based on the first embodiment described above, in this embodiment, step S20 includes:

[0076] Step S201: Adjust the format of the three-dimensional model to the target format, and import the three-dimensional model in the target format into the finite element analysis software.

[0077] Understandably, the target format 3D model is imported; the finite element analysis software can be ANSYS.

[0078] Step S202: Set the model parameters of the target format three-dimensional model using the finite element analysis software. The model parameter settings include mesh generation, material property configuration, and adding flexible multi-point constraint joints.

[0079] Step S203: Perform modal simulation on the model after configuring the model parameters to generate the first simulation result.

[0080] It is understandable that the first simulation result can be the result obtained by simulating a model with added flexible multi-point constraint joints. The first simulation result includes the first modal frequency, the first modal shape, and the first deformation contour map, etc.

[0081] Step S204: Modify the flexible multi-point constrained joint into a rigid multi-point constrained joint, and perform modal simulation on the modified model to generate a second simulation result.

[0082] It is understandable that the second simulation result can be the result obtained by replacing the flexible multi-point constrained joints in the model with rigid multi-point constrained joints and then performing modal simulation. The second simulation result includes the second modal frequency, the second modal shape, and the second deformation contour map, etc.

[0083] Furthermore, in order to improve the accuracy of the simulation, step S204 includes: performing modal simulation on the model after configuring the model parameters; adjusting the connection relationship between the component to be made flexible and other components according to the modal array and modal frequency generated by the modal simulation; performing modal simulation on the model after adjusting the connection relationship; and generating the first simulation result if the modal array and modal frequency generated after the simulation meet the preset conditions.

[0084] Understandably, the preset conditions can be the pre-set mode shape and modal frequency to end the simulation. After performing the modal simulation, it is determined whether the mode shape and modal frequency obtained after the modal simulation meet the preset conditions. If not, the connection between the flexible component and other components is adjusted, and the modal simulation is continued until the obtained mode shape and modal frequency meet the preset conditions.

[0085] Furthermore, in order to make the robot's links more flexible, step S30 includes: if the first simulation result and the second simulation result are consistent, exporting the component to be made more flexible; meshing the component to be made more flexible using the finite element analysis software and exporting the INP file of the component to be made more flexible; converting the INP file into a text file and importing the text file into the target software; performing modal order reduction on the component to be made more flexible using the target software based on the text file to generate reduced-order model data; generating a flexible body corresponding to the component to be made more flexible based on the reduced-order model data; replacing the rigid body corresponding to the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing link flexibility.

[0086] It is understandable that the modal frequencies and mode shapes in the first simulation result are consistent with those in the second simulation result, and the component to be made flexible can be derived; the text file can be a TXT file; the target software can be MATLAB software; the reduced-order model data includes the equivalent stiffness matrix, equivalent mass matrix and damping matrix.

[0087] In the specific implementation, if the mode shapes and modal frequencies in the first simulation result are consistent with those in the second simulation result, the component to be made flexible is exported. A Mesh module is established in the finite element analysis software, the component to be made flexible is imported into Geometry, and after mesh generation is completed in the mesh, the INP file of the component to be made flexible is exported. The INP file is converted into a TXT file and imported into MATLAB software. The modal order of the component to be made flexible is reduced using MATLAB software to generate the corresponding equivalent stiffness matrix, equivalent mass matrix, and damping matrix. Based on the equivalent stiffness matrix, equivalent mass matrix, and damping matrix, a flexible body of the component to be made flexible is generated, and the corresponding rigid body in the initial rigid body dynamics model is replaced with this flexible body to generate a rigid-flexible coupling model with linkage flexibility.

[0088] Furthermore, in order to make the robot's links more flexible to reproduce the robot's dynamic characteristics under different working conditions, the step of performing modal reduction on the component to be softened using the target software based on the text file to generate reduced-order model data includes: extracting mesh information from the text file using the target software, and establishing a geometric solid model corresponding to the component to be softened based on the extracted mesh information; performing modal reduction on the geometric solid model to be softened using the target software to generate an equivalent stiffness matrix and an equivalent mass matrix; generating a damping matrix based on the equivalent stiffness matrix and the equivalent mass matrix; and generating reduced-order model data based on the equivalent stiffness matrix, the equivalent mass matrix, and the damping matrix.

[0089] Understandably, the mesh information is extracted from the mesh TXT file using MATLAB software; an empty finite element container is created, and then the geometric solid model to be reduced in order is built based on the extracted mesh information.

[0090] In practice, the robot's 3D model format is adjusted and saved as an SCDOC format. SCDOC is a proprietary format of the SpaceClaim software. The SCDOC file is then directly imported into the Geometry module of ANSYS Workbench's Modal module. Within the Modal module, the model is meshed, material properties are configured, and flexible multi-point constraint joints (MPC-multipoint) are added. The model undergoes modal simulation. Based on the obtained modal frequencies and mode shapes, if these do not meet the preset conditions, the assembly relationship between the component to be made flexible and other components is adjusted (e.g., the robot's forearm needs flexibility, but the motor on the forearm does not; in the modal simulation, the motor is changed to a rigid body, and the assembly relationship between the forearm and the motor connection plate is adjusted). The adjusted model is then simulated again. If the simulated modal frequencies and mode shapes meet the preset conditions, the first simulation result is obtained. The model is then re-meshed in the Modal module of the finite element analysis software. A second-order tetrahedral mesh is selected for the component to be made flexible, and the mesh size of the component to be reduced in order does not exceed 500,000. Material properties are configured and constraints are added. The joints of the model are reconfigured, and the original flexible MPC is changed to a rigid MPC. The simulation is repeated to obtain the second simulation result. The first and second simulation results are compared. If the data are consistent, the mesh of the component to be made flexible is exported and processed in ANSYS. In Workbench, create a Mesh module, import the parts to be made flexible into Geometry, and then enter the mesh module to complete the mesh generation. Select second-order tetrahedrons for the mesh. In ANSYS Workbench, create Finite Elements. The Modeler module is connected to the Mesh module to export the INP file of the component to be made flexible. The INP file is then converted to a TXT file, and the internal format of the file is adjusted. The mesh TXT file is imported into MATLAB software, and mesh information is extracted from the mesh TXT file using MATLAB software. An empty finite element container is created, and a geometric solid model to be reduced in order is built based on the extracted mesh information. Material properties consistent with those used in modal simulation are set, connection interfaces consistent with actual kinematic constraints are set, and constraint relationships of the geometric solid model to be reduced in order are set (surface constraints are selected based on the connection interface, and the constraint method is multi-point constraint (MPC)). Modal reduction is performed using the Craig-Bampton method built into MATLAB to obtain the equivalent stiffness matrix and equivalent mass matrix corresponding to the geometric solid model to be reduced in order. A damping matrix is ​​generated based on the equivalent stiffness matrix and equivalent mass matrix. The damping model is a linear damping model. The equivalent stiffness matrix, equivalent mass matrix, and damping matrix are saved as the corresponding reduced-order model data.A FlexibleSolid module is added to the initial rigid body dynamics model, and the equivalent stiffness matrix, equivalent mass matrix, and damping matrix are written into the Flexible Solid module. This replaces the original rigid body with a flexible body. For example, if the component to be made flexible is a robot arm, the robot arm rigid body module (Solid module) named "Arm" in the initial rigid body dynamics model is deleted, and the two ends are connected to the Flexible Solid module corresponding to the arm, generating a rigid-flexible coupling model with flexible links.

[0091] This embodiment adjusts the format of the 3D model to the target format and imports the target format 3D model into finite element analysis software. The finite element analysis software is used to set model parameters for the target format 3D model, including mesh generation, material property configuration, and the addition of flexible multi-point constraint joints. Modal simulation is performed on the model after parameter configuration to generate a first simulation result. The flexible multi-point constraint joints are then modified to rigid multi-point constraint joints, and modal simulation is performed on the modified model to generate a second simulation result. This embodiment first adds flexible multi-point constraint joints for modal simulation, then modifies the flexible multi-point constraint joints to rigid multi-point constraint joints for modal simulation. When the modal simulation results are consistent, the mesh of the component to be made flexible is exported, improving the accuracy of robot link flexibility.

[0092] refer to Figure 4 , Figure 4 This is a flowchart illustrating the third embodiment of the robot rigid-flexible coupling model construction method of the present invention.

[0093] Based on the above embodiments, in this embodiment, step S40 includes:

[0094] Step S401: Create the functional module and rotary joint module using the target software.

[0095] It is understandable that the target software can be MATLAB software; the functional module can also be called the Function module; and the rotary joint module can also be called the Revolute Joint module.

[0096] Step S402: Based on historical input data and current input data, determine the module input and module output of the functional module, and generate a flexible joint module.

[0097] Understandably, based on historical and current input data, the final output of the flexible joint module can be determined. The final output can be categorized into four types: monotonically increasing, monotonically decreasing, monotonically increasing then decreasing, and monotonically decreasing then increasing.

[0098] Step S403: Use the torque output by the rotary joint module in the rigid-flexible coupling model with connecting rod flexibility as the input of the flexible joint module.

[0099] Step S404: Use the output of the flexible joint module as the input of the universal joint module, and adjust the internal mechanical properties and excitation mode of the universal joint module to generate a rigid-flexible coupling model corresponding to the robot.

[0100] In practical implementation, a Revolute Joint module is added to the rigid body dynamics model to configure the motion excitation of the joints. The torque is set to be automatically calculated, and the motion is set to be an external input. A Function module is added through MATLAB to build the joint flexibility module. This embodiment uses an optimized Preisach model to characterize the hysteresis characteristics of the robot joints. The one-dimensional form of the Preisach model is as follows:

[0101]

[0102] Where a is the amplitude, b is the mean, and c is the square of the variance, the Preisach model takes the following form after introducing the Everett function:

[0103]

[0104] When c approaches 1, applying L'Hôpital's rule to the above equation yields the following relationship:

[0105]

[0106] If c≠1, E V1 =E V0 -E(x,y), E V1 E is the current output value. V0 This is the output value from the previous time step; if c = 1, E V1 =E V0+limE(x,y), combining historical and current input data, the final output result is divided into four types: ① monotonically increasing; ② monotonically decreasing; ③ first monotonically increasing then decreasing (the step line part in the Preisach function); ④ first monotonically decreasing then increasing. These four output results can be represented as follows: monotonically increasing: Out1 = -Ev1; monotonically decreasing: Out1 = Ev1; first monotonically increasing then decreasing: Out1 = Out0 - 2*Ev1; first monotonically decreasing then increasing: Out1 = Out0 + 2*Ev1, where Out1 is the current output value (current angle), and Out0 is the previously saved historical output (historical angle). In this example, the input in the MATLAB Function is torque, and the output is angle. The Revolute Joint module is adjusted to output its torque sensing. The output torque is used as the input to the flexible joint module. A delay module and an adder module are added. The output of the flexible joint module is connected to the delay module, then to the adder. The final result is connected to the Gimbal. The input from the Joint module generates a rigid-flexible coupling model.

[0107] This embodiment creates functional modules and rotary joint modules using target software. Based on historical and current input data, it determines the module inputs and outputs of the functional modules to generate a flexible joint module. The torque output from the rotary joint module in the rigid-flexible coupling model with linkage flexibility is used as the input to the flexible joint module. The output of the flexible joint module is used as the input to the universal joint module, and the internal mechanical properties and excitation mode of the universal joint module are adjusted to generate a rigid-flexible coupling model corresponding to the robot. This embodiment determines the inputs and outputs of the functional modules based on historical and current input data, thereby generating a flexible joint module. The torque output from the rotary joint module in the rigid body dynamics model is used as the input to the flexible joint model, and the output of the flexible joint model is used as the input to the universal joint module. Adjusting the internal mechanical properties and excitation mode of the universal joint module generates a rigid-flexible coupling model of the robot. This model can reproduce the dynamic characteristics of the robot under different working conditions and can also provide the robot's joint torques and rotation angles, improving the accuracy of robot motion state simulation.

[0108] Furthermore, this embodiment of the invention also proposes a storage medium storing a robot rigid-flexible coupling model construction program, which, when executed by a processor, implements the steps of the robot rigid-flexible coupling model construction method described above.

[0109] Reference Figure 5 , Figure 5 This is a structural block diagram of the first embodiment of the robot rigid-flexible coupling model construction device of the present invention.

[0110] like Figure 5As shown, the robot rigid-flexible coupling model construction device proposed in this embodiment of the invention includes:

[0111] The model building module 10 is used to build a three-dimensional model of the robot and to build an initial rigid body dynamics model of the robot based on the three-dimensional model.

[0112] Modal simulation module 20 is used to adjust the format of the three-dimensional model to the target format and perform modal simulation on the three-dimensional model in the target format;

[0113] The generation module 30 is used to generate a flexible body corresponding to the link of the robot based on the simulation results of the modal simulation, and replace the rigid body corresponding to the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing the link flexibility.

[0114] The rigid-flexible coupling model establishment module 40 is used to establish the flexible joint module corresponding to the joint of the robot, and to incorporate the flexible joint module into the rigid-flexible coupling model containing the linkage flexibility to generate a rigid-flexible coupling model corresponding to the robot.

[0115] This embodiment establishes a 3D model of the robot and, based on this 3D model, establishes an initial rigid-body dynamics model of the robot. The format of the 3D model is adjusted to a target format, and modal simulation is performed on the target format 3D model. Based on the simulation results of the modal simulation, flexible bodies corresponding to the robot's links are generated, and the corresponding rigid bodies in the initial rigid-body dynamics model are replaced with these flexible bodies, generating a rigid-flexible coupling model containing link flexibility. Flexible joint modules corresponding to the robot's joints are established, and these flexible joint modules are incorporated into the rigid-flexible coupling model containing link flexibility, generating a rigid-flexible coupling model corresponding to the robot. This embodiment comprehensively considers the influence of link flexibility and joint flexibility on the robot's dynamics model. The constructed rigid-flexible coupling model can not only reproduce the dynamic characteristics of the robot under different working conditions but also accurately provide the robot's joint torques and rotation angles, thereby improving the accuracy of industrial robot motion state simulation.

[0116] Based on the first embodiment of the robot rigid-flexible coupling model construction device of the present invention, a second embodiment of the robot rigid-flexible coupling model construction device of the present invention is proposed.

[0117] In this embodiment, the model building module 10 is further configured to build a three-dimensional model of the robot using three-dimensional modeling software, configure the parameters of the three-dimensional model according to the parameters of the robot, export the three-dimensional model after parameter configuration as an Extensible Markup Language (XML) form, and generate an initial rigid body dynamics model of the robot according to the XML form.

[0118] The modal simulation module 20 is further configured to adjust the format of the three-dimensional model to a target format and import the three-dimensional model in the target format into finite element analysis software; set model parameters for the three-dimensional model in the target format using the finite element analysis software, including mesh generation, material property configuration, and adding flexible multi-point constraint joints; perform modal simulation on the model after parameter configuration to generate a first simulation result; modify the flexible multi-point constraint joints to rigid multi-point constraint joints, and perform modal simulation on the modified model to generate a second simulation result.

[0119] The modal simulation module 20 is also used to perform modal simulation on the model after the model parameters are configured, adjust the connection relationship between the flexible component and other components according to the modal array and modal frequency generated by the modal simulation, perform modal simulation on the model after the connection relationship is adjusted, and generate the first simulation result if the modal array and modal frequency generated after the simulation meet the preset conditions.

[0120] The generation module 30 is further configured to: export the component to be made flexible when the first simulation result is consistent with the second simulation result; mesh the component to be made flexible using the finite element analysis software and export the INP file of the component to be made flexible; convert the INP file into a text file and import the text file into the target software; perform modal order reduction on the component to be made flexible using the target software based on the text file to generate reduced-order model data; generate a flexible body corresponding to the component to be made flexible based on the reduced-order model data; and replace the rigid body corresponding to the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing link flexibility.

[0121] The generation module 30 is further configured to extract mesh information from the text file using the target software, and establish a geometric entity model to be reduced in order corresponding to the component to be softened based on the extracted mesh information; perform modal reduction on the geometric entity model to be reduced in order using the target software to generate an equivalent stiffness matrix and an equivalent mass matrix; generate a damping matrix based on the equivalent stiffness matrix and the equivalent mass matrix; and generate reduced-order model data based on the equivalent stiffness matrix, the equivalent mass matrix, and the damping matrix.

[0122] The rigid-flexible coupling model building module 40 is also used to create functional modules and rotary joint modules through target software; determine the module input and module output of the functional modules based on historical input data and current input data, and generate flexible joint modules; use the torque output of the rotary joint module in the rigid-flexible coupling model with linkage flexibility as the input of the flexible joint module; use the output of the flexible joint module as the input of the universal joint module, and adjust the internal mechanical properties and excitation mode of the universal joint module to generate a rigid-flexible coupling model corresponding to the robot.

[0123] Other embodiments or specific implementations of the robot rigid-flexible coupling model construction device of the present invention can be referred to the above-described method embodiments, and will not be repeated here.

[0124] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0125] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0126] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory / random access memory, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0127] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for constructing a rigid-flexible coupling model of a robot, characterized in that, The method includes: Establish a three-dimensional model of the robot, and establish an initial rigid body dynamics model of the robot based on the three-dimensional model; The format of the 3D model is adjusted to the target format, and modal simulation is performed on the 3D model in the target format. Based on the simulation results of modal simulation, a flexible body corresponding to the link of the robot is generated, and the corresponding rigid body in the initial rigid body dynamics model is replaced with the flexible body to generate a rigid-flexible coupling model with link flexibility. Establish flexible joint modules corresponding to the joints of the robot, and incorporate the flexible joint modules into the rigid-flexible coupling model containing flexible links to generate a rigid-flexible coupling model corresponding to the robot. The step of adjusting the format of the 3D model to the target format and performing modal simulation on the 3D model in the target format includes: Adjust the format of the 3D model to the target format, and import the 3D model in the target format into the finite element analysis software; The finite element analysis software is used to set the model parameters of the target format three-dimensional model. The model parameter settings include mesh generation, material property configuration, and adding flexible multi-point constrained joints. Perform modal simulation on the model after configuring the model parameters to generate the first simulation result; The flexible multi-point constrained joint is modified into a rigid multi-point constrained joint, and modal simulation is performed on the modified model to generate a second simulation result. The process of generating a flexible body corresponding to the robot's links based on the simulation results of modal simulation, and replacing the corresponding rigid body in the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing link flexibility, includes: If the first simulation result is consistent with the second simulation result, the component to be made flexible is derived. The finite element analysis software is used to mesh the component to be made flexible, and the INP file of the component to be made flexible is exported. Convert the INP file into a text file and import the text file into the target software; The target software performs modal reduction on the component to be made flexible based on the text file, generating reduced-order model data. Generate a flexible body corresponding to the component to be made flexible based on the reduced-order model data; The rigid body in the initial rigid body dynamics model is replaced with the flexible body to generate a rigid-flexible coupling model with flexible linkage.

2. The method as described in claim 1, characterized in that, The process of establishing a three-dimensional model of the robot and, based on the three-dimensional model, establishing an initial rigid body dynamics model of the robot includes: A 3D model of the robot is created using 3D modeling software, and the parameters of the 3D model are configured according to the parameters of the robot. Export the 3D model after parameter configuration as an Extensible Markup Language (Extreme Markup Language) format; The initial rigid body dynamics model of the robot is generated according to the Extensible Markup Language (EXPLAIN) format.

3. The method as described in claim 1, characterized in that, The modal simulation of the model after parameter configuration to generate the first simulation result includes: Modal simulation is performed on the model after the model parameters are configured. The connection relationship between the flexible component and other components is adjusted according to the modal array and modal frequency generated by the modal simulation. Modal simulation was performed on the model after the connection relationships were adjusted; If the modal array and modal frequencies generated after simulation meet the preset conditions, the first simulation result is generated.

4. The method as described in claim 3, characterized in that, The step of performing modal reduction on the component to be made flexible using the target software based on the text file to generate reduced-order model data includes: The target software extracts mesh information from the text file and establishes a geometric solid model of the component to be made flexible based on the extracted mesh information. The target software is used to perform modal order reduction on the geometric solid model to be reduced, generating an equivalent stiffness matrix and an equivalent mass matrix; A damping matrix is ​​generated based on the equivalent stiffness matrix and the equivalent mass matrix; Reduced-order model data is generated based on the equivalent stiffness matrix, the equivalent mass matrix, and the damping matrix.

5. The method as described in claim 1 or 2, characterized in that, The process of establishing flexible joint modules corresponding to the robot's joints and incorporating these flexible joint modules into the rigid-flexible coupling model containing flexible links to generate a rigid-flexible coupling model corresponding to the robot includes: Create functional modules and rotary joint modules using the target software; Based on historical and current input data, the module input and module output of the functional module are determined, and a flexible joint module is generated. The torque output by the rotary joint module in the rigid-flexible coupling model with connecting rod flexibility is used as the input of the flexible joint module; The output of the flexible joint module is used as the input of the universal joint module, and the internal mechanical properties and excitation mode of the universal joint module are adjusted to generate a rigid-flexible coupling model corresponding to the robot.

6. A robot rigid-flexible coupling model construction device, characterized in that, The device includes: The model building module is used to build a three-dimensional model of the robot and, based on the three-dimensional model, to build an initial rigid body dynamics model of the robot. The modal simulation module is used to adjust the format of the 3D model to the target format and perform modal simulation on the 3D model in the target format. The generation module is used to generate the flexible body corresponding to the link of the robot based on the simulation results of the modal simulation, and replace the rigid body corresponding to the initial rigid body dynamics model with the flexible body to generate a rigid-flexible coupling model containing the link flexibility. The rigid-flexible coupling model establishment module is used to establish the flexible joint module corresponding to the joint of the robot, and to incorporate the flexible joint module into the rigid-flexible coupling model containing the linkage flexibility to generate a rigid-flexible coupling model corresponding to the robot. The modal simulation module is also used for: Adjust the format of the 3D model to the target format, and import the 3D model in the target format into the finite element analysis software; The finite element analysis software is used to set the model parameters of the target format three-dimensional model. The model parameter settings include mesh generation, material property configuration, and adding flexible multi-point constrained joints. Perform modal simulation on the model after configuring the model parameters to generate the first simulation result; The flexible multi-point constrained joint is modified into a rigid multi-point constrained joint, and modal simulation is performed on the modified model to generate a second simulation result. The generation module is further configured to: If the first simulation result is consistent with the second simulation result, the component to be made flexible is derived. The finite element analysis software is used to mesh the component to be made flexible, and the INP file of the component to be made flexible is exported. Convert the INP file into a text file and import the text file into the target software; The target software performs modal reduction on the component to be made flexible based on the text file, generating reduced-order model data. Generate a flexible body corresponding to the component to be made flexible based on the reduced-order model data; The rigid body in the initial rigid body dynamics model is replaced with the flexible body to generate a rigid-flexible coupling model with flexible linkage.

7. A robot rigid-flexible coupling model construction device, characterized in that, The device includes: a memory, a processor, and a robot rigid-flexible coupling model building program stored in the memory and executable on the processor, the robot rigid-flexible coupling model building program being configured to implement the steps of the robot rigid-flexible coupling model building method as described in any one of claims 1 to 5.

8. A storage medium, characterized in that, The storage medium stores a robot rigid-flexible coupling model construction program, which, when executed by a processor, implements the steps of the robot rigid-flexible coupling model construction method as described in any one of claims 1 to 5.

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