Assembly mechanics modeling method for flexible gripper shaft assembly process

Abstract

The present application relates to an assembly mechanics modeling method for a flexible gripping shaft assembly process, wherein the method comprises: constructing a force-position mapping model of suction cup deformation based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque received by the end of the flexible suction cup; constructing a force-position mapping model of shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque; constructing a numerical simulator for the flexible gripping shaft-hole assembly process based on the force-position mapping model of suction cup deformation and the force-position mapping model of shaft-hole contact; designing a compliant control strategy for the flexible gripping shaft-hole assembly process based on the force-position mapping model of suction cup deformation and the force-position mapping model of shaft-hole contact, and verifying the compliant control strategy using a numerical simulator. The embodiment of the present application constructs a force-position mapping model of suction cup deformation and a force-position mapping model of shaft-hole contact, which can well guide the design of the compliant control strategy of the flexible gripping shaft-hole assembly system, and constructs an assembly simulator that is easy to deploy, which can analyze the relationship between the system's posture error and force response in real time, and verify the control effect using the constructed simulator, thereby achieving a more compliant control effect.

Description

Technical Field

[0001] The present application relates to the technical field of robot automated assembly, and in particular to an assembly mechanics modeling method for a flexible gripping shaft assembly process. Background Art

[0002] In the manufacturing process of 3C products, assembly is a key link in the product manufacturing and production process and one of the main factors affecting product performance, quality, development cycle, and cost. However, high-precision 3C product assembly tasks are still mainly completed manually, which has the disadvantages of low efficiency, poor quality, and high cost. Robotic precision shaft-and-hole assembly technology can help improve the level of automation, thereby ensuring assembly quality and improving assembly efficiency. Modeling and analyzing the mechanical characteristics of the shaft-and-hole assembly process helps to understand the shaft-and-hole posture error and force relationship during the robot assembly process, thereby assisting in the design of a compliant control strategy.

[0003] 3C products contain numerous small parts (cross-sectional dimensions ranging from a few millimeters to tens of millimeters, and thicknesses ranging from 10-1mm to several millimeters). These parts are typically not gripped by rigid robot fingers and instead require flexible suction cups. While flexible gripping can act as a passive, compliant link to reduce contact forces during assembly, it also requires more complex mechanical properties and modeling.

[0004] However, there is still a lack of research and discussion on the mechanical modeling of shaft-hole assembly for flexible grasping in related technologies, which makes it difficult to assist in the design of flexible control strategies and urgently needs to be improved. Summary of the Invention

[0005] The present application provides an assembly mechanics modeling method for a flexible gripping shaft assembly process, in order to solve the problems that the related art still lacks research and discussion on the shaft hole assembly mechanics modeling for flexible gripping, and it is difficult to assist in the design of a flexible control strategy.

[0006] The first aspect of the present application provides an assembly mechanics modeling method for a flexible gripping shaft assembly process, comprising the following steps: constructing a force-position mapping model of suction cup deformation based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup; constructing a force-position mapping model of shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque; calculating the actual values ​​of the shaft-hole posture error, the actual deformation of the suction cup and the actual contact force of the shaft-hole at each moment in the flexible gripping shaft-hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and constructing a numerical simulation method for the flexible gripping shaft-hole assembly process based on the actual values, so as to construct a numerical simulator for the flexible gripping shaft-hole assembly process using the numerical simulation method; designing a compliant control strategy for the flexible gripping shaft-hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and verifying the compliant control strategy using the numerical simulator to obtain the final assembly control result of the flexible gripping shaft assembly process.

[0007] Optionally, in one embodiment of the present application, the force-position mapping model of the suction cup deformation is constructed based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup, including: calculating the deformation of the force and the torque applied to the end of the flexible suction cup based on the deformation characteristics and cylindrical characteristics of the flexible suction cup, and algebraically superimposing the deformation to generate a superimposed value of the deformation; using the superimposed value to obtain the mathematical relationship between the real-time deformation of the flexible suction cup and the force and the torque, and constructing the force-position mapping model of the suction cup deformation according to the mathematical relationship.

[0008] Optionally, in one embodiment of the present application, the force-position mapping model of the shaft-hole contact is constructed based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque, including: dividing the shaft hole into at least one discrete element on each height section, and calculating the force and torque generated by the local pressure and friction force of the at least one discrete element in the shaft coordinate system; numerically integrating the force and the torque to generate the corresponding shaft-hole contact force and torque, and constructing the force-position mapping model of the shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque.

[0009] Optionally, in one embodiment of the present application, the use of the numerical simulation method to construct a numerical simulator for the flexible gripping shaft hole assembly process includes: obtaining the initial posture error of the shaft hole before the flexible gripping shaft hole is assembled; based on the initial posture error of the shaft hole, assembling the flexible gripping shaft hole using a preset control strategy until the shaft is inserted into the hole, generating a force and torque curve of the flexible gripping shaft hole, and based on the force and torque curve of the flexible gripping shaft hole, constructing a numerical simulator for the flexible gripping shaft hole assembly process.

[0010] Optionally, in one embodiment of the present application, the compliant control strategy for the flexible grasping shaft-hole assembly process is designed based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, including: based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, using a preset force system translation theorem to design a function to respectively estimate the force and torque applied to the end point of the suction cup and the force and torque applied to the center of the shaft insertion depth; inputting the force and torque applied to the end point of the suction cup into an inverse model of the suction cup force-position model, To generate the actual deformation of the suction cup, and use a preset ratio to convert the actual deformation of the suction cup into a four-dimensional incremental motion; input the force and the torque received by the shaft when inserted into the depth center into a second-order admittance controller to output a six-dimensional incremental motion; integrate the four-dimensional incremental motion and the six-dimensional incremental motion to generate an incremental motion control quantity that meets the preset expected conditions, and control the assembly process of the flexible gripping shaft according to the incremental motion control quantity that meets the preset expected conditions, so as to obtain a compliant control strategy for the flexible gripping shaft hole assembly process.

[0011] The second embodiment of the present application provides an assembly mechanics modeling device for a flexible gripping shaft assembly process, including: a first construction module for constructing a force-position mapping model of suction cup deformation based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup; a second construction module for constructing a force-position mapping model of shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque; a calculation module for calculating the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact at each moment in the flexible gripping shaft-hole assembly process. The actual numerical values ​​of the shaft-hole posture error, the actual deformation of the suction cup and the actual contact force of the shaft-hole are obtained, and a numerical simulation method of the flexible grasping shaft-hole assembly process is constructed based on the actual numerical values, so as to construct a numerical simulator of the flexible grasping shaft-hole assembly process using the numerical simulation method; an assembly control module is used to design a compliant control strategy for the flexible grasping shaft-hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and verify the compliant control strategy using the numerical simulator to obtain the final assembly control result of the flexible grasping shaft assembly process.

[0012] Optionally, in one embodiment of the present application, the first construction module includes: a first calculation unit, used to calculate the deformation of the force and the torque exerted on the end of the flexible suction cup based on the deformation characteristics and cylindrical characteristics of the flexible suction cup, and algebraically superimpose the deformation to generate a superimposed value of the deformation; a first construction unit, used to use the superimposed value to obtain the mathematical relationship between the real-time deformation of the flexible suction cup and the force and the torque, and construct a force-position mapping model of the suction cup deformation based on the mathematical relationship.

[0013] Optionally, in one embodiment of the present application, the second construction module includes: a first calculation unit, used to divide the shaft hole into at least one discrete element on each height section, and calculate the force and torque generated by the local pressure and friction force of the at least one discrete element in the shaft coordinate system; a second construction unit, used to numerically integrate the force and the torque to generate the corresponding shaft hole contact force and torque, and construct a force-position mapping model of the shaft hole contact based on the mathematical relationship between the shaft hole posture error and the corresponding shaft hole contact force and torque.

[0014] Optionally, in one embodiment of the present application, the calculation module includes: an acquisition unit for acquiring the initial posture error of the shaft hole before the flexible gripping shaft hole is assembled; a generation unit for assembling the flexible gripping shaft hole based on the initial posture error of the shaft hole and using a preset control strategy until the shaft is inserted into the hole, generating a force and torque curve of the flexible gripping shaft hole, and constructing a numerical simulator of the flexible gripping shaft hole assembly process based on the force and torque curve of the flexible gripping shaft hole.

[0015] Optionally, in one embodiment of the present application, the assembly control module includes: an estimation unit, which is used to estimate the force and torque acting on the end point of the suction cup and the force and torque acting on the center of the shaft insertion depth respectively based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, using a preset force system translation theorem design function; an input unit, which is used to input the force and torque acting on the end point of the suction cup into an inverse model of the suction cup force-position model to generate an actual deformation of the suction cup, and convert the actual deformation of the suction cup into a four-dimensional incremental motion using a preset ratio; an output unit, which is used to input the force and torque acting on the shaft at the center of the depth when inserted into a second-order admittance controller to output a six-dimensional incremental motion; an integration unit, which is used to integrate the four-dimensional incremental motion and the six-dimensional incremental motion to generate an incremental motion control quantity that meets preset expected conditions, and control the assembly process of the flexible gripping shaft according to the incremental motion control quantity that meets the preset expected conditions, to obtain a compliant control strategy for the flexible gripping shaft-hole assembly process.

[0016] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the assembly mechanics modeling method for the flexible gripping shaft assembly process as described in the above embodiment.

[0017] A fourth aspect of the present application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the assembly mechanics modeling method for the flexible gripping shaft assembly process as described above.

[0018] The embodiment of the present application constructs a mechanical model of a flexible gripping shaft-hole assembly system and models two key mechanical links therein, which can well guide the design of a compliant control strategy for the flexible gripping shaft-hole assembly system. The embodiment of the present application also constructs an easily deployable assembly simulator that can analyze the relationship between the system's posture error and force response in real time, which is of significant significance for the design and verification of the controller. The constructed simulator is used to verify the control effect, achieving a more compliant control effect than FBCC (feature-based compliant control strategy). This solves the problem that the related art still lacks research and discussion on the mechanical modeling of flexible gripping shaft-hole assembly, making it difficult to assist in the design of compliant control strategies.

[0019] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 This is a flow chart of an assembly mechanics modeling method for a flexible gripping shaft assembly process provided in accordance with an embodiment of the present application;

[0022] Figure 2 A diagram of a robot flexible gripping shaft assembly system according to one embodiment of the present application;

[0023] Figure 3 According to one embodiment of the present application, S 、M S Schematic diagram of suction cup deformation caused by various components;

[0024] Figure 4 A diagram of a potential mapping model for calculating shaft-hole contact force using discrete element method according to one embodiment of the present application;

[0025] Figure 5is a calculation flow chart of an assembly simulator according to one embodiment of the present application;

[0026] Figure 6 A block diagram of a high compliance control strategy for a flexible deformation model of a suction cup according to an embodiment of the present application;

[0027] Figure 7 This is a comparison diagram of control effects according to one embodiment of the present application;

[0028] Figure 8 Schematic diagram of the structure of an assembly mechanics modeling device for a flexible gripping shaft assembly process provided in an embodiment of the present application;

[0029] Figure 9 A schematic diagram of the structure of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0031] The following describes the assembly mechanics modeling method of the flexible gripping shaft assembly process in the embodiment of the present application with reference to the accompanying drawings. In view of the problem that the related art mentioned in the above background technology still lacks research and discussion on the assembly mechanics modeling of the shaft hole for flexible gripping, and it is difficult to assist in the design of a compliant control strategy, the present application provides an assembly mechanics modeling method of the flexible gripping shaft assembly process. In this method, the two key mechanical links are modeled, which can well guide the design of the compliant control strategy of the flexible gripping shaft hole assembly system. In addition, the embodiment of the present application constructs an easy-to-deploy assembly simulator, which can analyze the relationship between the posture error and force response of the system in real time, which has significant significance for the design and verification of the controller, and uses the constructed simulator to verify the control effect. Compared with FBCC (feature-based compliant control strategy), it achieves a more compliant control effect. Thus, it solves the problem that the related art still lacks research and discussion on the assembly mechanics modeling of the shaft hole for flexible gripping, and it is difficult to assist in the design of a compliant control strategy.

[0032] Specifically, Figure 1 A schematic flow chart of an assembly mechanics modeling method for a flexible gripping shaft assembly process provided in an embodiment of the present application.

[0033] like Figure 1 As shown, the assembly mechanics modeling method of the flexible gripping shaft assembly process includes the following steps:

[0034] In step S101, a force-position mapping model of the suction cup deformation is constructed based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup.

[0035] It is understandable that the embodiment of the present application can be used to analyze the flexible gripping shaft hole system, wherein the flexible gripping shaft hole assembly system is as follows: Figure 2 As shown. The flexible suction cup installed at the end of the robot arm flexibly grasps the shaft parts and drives the shaft parts to translate and rotate in the Cartesian space; while the hole parts are fixed in the environment and their posture remains unchanged. During the assembly process, the contact caused by the posture error between the shaft and the hole will generate dynamically changing contact force. The force sensor fixed at the end of the robot arm can measure the force signal in real time. Five coordinate systems are defined in this system: (1) Force sensor coordinate system O F -X F Y F Z F Usually located at its force measurement center; (2) The end coordinate system of the manipulator O E -X E Y E Z E Located at the TCP point at the end of the robotic arm; (3) Coordinate system O of the flexible suction cup S -X S Y S Z S Set at the center of its lower surface, Z S The axis direction is parallel to the axis of the suction cup and points to its upper surface; (4) Axis coordinate system O P -X P Y P Z P Fixed at the center of the lower surface of the shaft parts, Z P The axial direction is parallel to the axis and points to its upper surface; (5) Hole coordinate system O H -X H Y H Z H Fixed at the center of the lower surface of the hole part, Z H The axis direction is parallel to the axis and points to its upper surface.

[0036] During the assembly process, due to the misalignment of the position and angle of the shaft hole (hereinafter referred to as posture error), the shaft is subjected to contact force and torque from the hole, which are uniformly represented in the shaft coordinate system O P -X P Y P Z P At the origin, denoted as F P and M P At the same time, the suction cup will also produce position deviation and angle bending (hereinafter collectively referred to as deformation). The deformation of the suction cup is mainly related to its end (i.e. S -XS Y S Z S The force and moment at the origin are related and are denoted as F S and M S . Therefore, there are actually two sets of force and posture relationships in the flexible gripping shaft-hole assembly system: (1) Force-position mapping model of suction cup deformation: a mathematical model of the real-time deformation of the flexible suction cup and the force / torque exerted on its end; (2) Force-position mapping model of shaft-hole contact: a mathematical model of the shaft-hole posture error and the resulting contact force / torque. The mechanisms of these two sets of force-position mapping models are completely different and need to be modeled separately. It should be noted that the generalized rigid gripping shaft-hole assembly system only has the latter force-position mapping model, which is simpler. The force sensor cannot directly measure F P / M P and F S / M S Take measurements and remember that the force and torque measured by the force sensor are F F and M F , which is located at O F -X F Y F Z F The origin of .

[0037] The pose relationship of the assembly system at each moment is defined as follows: Represents the homogeneous transformation matrix from the robot end coordinate system to the hole coordinate system, Represents the homogeneous transformation matrix from the robot end coordinate system to the suction cup coordinate system, Represents the homogeneous transformation matrix from the suction cup coordinate system to the axis coordinate system, Represents the homogeneous transformation matrix from the axis coordinate system to the hole coordinate system, which has the following relationship:

[0038]

[0039] Mathematically, the force-position mapping model of the suction cup deformation will construct F S 、M S and The mathematical relationship is expressed as

[0040] The force-potential mapping model of shaft-hole contact will construct F P 、M P and The mathematical relationship is expressed as It represents the comprehensive posture error of the end of the robotic arm; is a constant parameter matrix related to the geometric dimensions of the axis, as shown in formula (2), x gsp and y gsp Indicates the grasping position error, which is usually very small; l PIndicates the height of the shaft. In the ideal assembly state (the shaft hole is completely aligned), and There is only a translation component in the z direction, where l S Indicates the length of the suction cup, l H Indicates the depth of the hole, z i Indicates the current insertion depth.

[0041]

[0042] During the actual implementation process, the embodiment of the present application can construct a force-position mapping model of the suction cup deformation based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque exerted on the end of the flexible suction cup. Different from the traditional rigid grasping shaft-hole assembly system, the present application constructs a mechanical model of the flexible grasping shaft-hole assembly system and models the two key mechanical links therein, which can well guide the design of the compliant control strategy of the flexible grasping shaft-hole assembly system.

[0043] Optionally, in one embodiment of the present application, a force-position mapping model of the suction cup deformation is constructed based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup, including: calculating the deformation of the force and torque applied to the end of the flexible suction cup based on the deformation characteristics and cylindrical characteristics of the flexible suction cup, and algebraically superimposing the deformation to generate a superimposed numerical value of the deformation; using the superimposed numerical value to obtain the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque, and constructing a force-position mapping model of the suction cup deformation based on the mathematical relationship.

[0044] Among them, considering the suction cup has small deformation and cylindrical characteristics, it is theoretically abstracted as a cantilever beam and modeled based on the relevant theories of material mechanics. According to the superposition principle, the deflection or rotation of any section of the beam under the simultaneous action of various loads is equal to the algebraic sum of the deflections or rotations of the same section of the beam under the action of each load separately. Therefore, F can be calculated separately. S 、M S The deformation caused by each component is algebraically superimposed. Since the main factors affecting the flexibility of the assembly process are the posture error and force in the X and Y directions, F is not considered for the time being. S,z and M S,z Resulting in Z S If necessary, it can be supplemented with a linear spring / torsion spring model for calculation. S The cross section is uniform along the X S and Y S The moment of inertia I of the axis is the same, let E be the elastic modulus of the suction cup. Figure 3 As shown, calculate Y S O S Z S F under the cross sectionS,y The amount of deformation, Y S O S Z S Cross-section lower M S,x The amount of deformation, X S O S Z S F under the cross section S,x The amount of deformation, X S O S Z S Cross-section lower M S,y The deformation generated in cases (a) to (d) is shown in formulas (3) to (6), respectively.

[0045]

[0046] By adding the values, the comprehensive deformation and F can be obtained. S 、M S The specific mathematical calculation relationship is shown in formula (7).

[0047]

[0048] As defined above The formats match each other, and it is necessary to further convert [Δx S ,Δy S ,Δα S ,Δβ S ] T Convert to It is characterized as shown in formula (8).

[0049]

[0050] The rpytoR() function converts the XYZ Euler angles of rotation around a fixed axis into a rotation matrix.

[0051] In step S102, a force-position mapping model of the shaft-hole contact is constructed based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque.

[0052] During the actual implementation process, the embodiment of the present application can construct a force-position mapping model of shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque. By constructing a mechanical model of the flexible grasping shaft-hole assembly system and modeling the two key mechanical links therein, it can well guide the design of the compliant control strategy of the flexible grasping shaft-hole assembly system.

[0053] Optionally, in one embodiment of the present application, a force-position mapping model of shaft-hole contact is constructed based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque, including: dividing the shaft hole into at least one discrete element on each height section, and calculating the force and torque generated by the local pressure and friction force of at least one discrete element in the shaft coordinate system; numerically integrating the force and torque to generate the corresponding shaft-hole contact force and torque, and constructing a force-position mapping model of shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque.

[0054] The contact force between the shaft and the hole is calculated using the discrete element method. The shaft and the hole are divided into many discrete microelements with small areas at each height section. The local pressure and friction force received by each microelement are calculated based on the linear elastic assumption. P Then, for all the infinitesimals at O P By integrating the force and moment generated at the point, the contact force / moment value between the shaft and the hole can be obtained.

[0055] like Figure 4 As shown, let the elastic modulus of the shaft be E P , the elastic model of the hole is E H , then in the unit area infinitesimal element P i The local pressure on the shaft is The local friction value is Its P The force generated and torque It can be calculated according to formula (9) (for the convenience of calculation, the force here is and torque The direction is consistent with the hole coordinate system).

[0056]

[0057] in, is the infinitesimal element P i The center is at O H -X H Y H Z H The coordinates below, O P In O H -X H Y H Z H The coordinates under Calculated; is the area of ​​the infinitesimal element; μ is the friction coefficient between the shaft and the hole; r H is the radius of the hole.

[0058] Then, numerical integration of each area element can be performed to obtain the contact between the shaft and the hole. P The forces and moments generated at are as follows, which constructs

[0059]

[0060] In actual calculation, the axis coordinate system O P -X P Y P Z P The height and angle directions are uniformly discretized into k scattered points in advance, and the coordinates of each scattered point in the axis coordinate system are recorded. At this time, each scattered point represents the center of the small area microelement around it, forming a total of k equal area microelements. Calculate the three-dimensional coordinates of each scattered point in the hole coordinate system Then substitute into formulas (9) and (10) to solve.

[0061] In step S103, based on the force-position mapping model of suction cup deformation and the force-position mapping model of shaft-hole contact, the actual values ​​of the shaft-hole posture error, the actual deformation of the suction cup and the actual contact force of the shaft-hole at each moment in the flexible grasping shaft-hole assembly process are calculated, and a numerical simulation method of the flexible grasping shaft-hole assembly process is constructed according to the actual values, so as to construct a numerical simulator of the flexible grasping shaft-hole assembly process using the numerical simulation method.

[0062] In the actual implementation process, the force F calculated by the force mapping model of the shaft-hole contact P / Torque M P The point of action is O P At, press O in XYZ direction H -X H Y H Z H The axis direction is represented; the force F calculated by the force mapping model of the suction cup deformation S / Torque M S The point of action is O S At, press O in XYZ direction E -X E Y E Z E The axis direction is indicated. E -X E Y E Z E and O H -X H Y H Z H There will not be a large deviation angle (usually less than 1°), so the XYZ directions of the above two forces can be considered to be consistent.P and M P The point of action is represented by O S , recorded as and Calculate according to formula (11). Since the force arms in the X and Y directions are very small, the additional torque generated by the force translation theorem is very small and can be ignored.

[0063]

[0064] According to the quasi-static hypothesis and Newton's equilibrium theorem, The components of F S 、M S The corresponding components of are equal, that is:

[0065]

[0066] The application embodiment can be based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and use optimization means to solve in real time the specific values ​​of the actual shaft-hole posture error, the actual deformation of the suction cup, and the actual contact force of the shaft-hole at each moment in an assembly process, thereby forming an assembly simulation method, and the control algorithm can be developed and verified based on this simulation method.

[0067] Optionally, in one embodiment of the present application, a numerical simulator for the flexible gripping shaft hole assembly process is constructed based on actual numerical values, including: obtaining the initial posture error of the shaft hole before the flexible gripping shaft hole is assembled; based on the initial posture error of the shaft hole, assembling the flexible gripping shaft hole using a preset control strategy until the shaft is inserted into the hole, generating a force and torque curve of the flexible gripping shaft hole, and constructing a numerical simulator for the flexible gripping shaft hole assembly process based on the force and torque curve of the flexible gripping shaft hole.

[0068] Among them, the embodiment of the present application can give the relative posture error of the end of the manipulator and the hole at any time based on the above modeling and calculation content Find the constraint that satisfies formula (1) and The system force and torque are calculated according to the two sets of force-position mapping relationships, so that the system satisfies the mechanical equilibrium requirements represented by formula (12). At this time, the system is in a stable state (the unstable state does not exist in reality). Then, F in the stable state P , M P , F S , M S It can also be calculated by formula (7)-(10). Thus, a simulator for the assembly process can be constructed, and the input of each step of the simulator is The output is the full state of the assembly system ( F P , M P , FS , M S In this numerical simulator, the initial position error of the shaft and hole before assembly can be given, and assembly can be performed using a control strategy (such as PID control, admittance control, or other user-defined control strategies). Multiple simulation steps can be run until the shaft is fully inserted into the hole. The force / torque curve of the entire assembly process can be obtained to verify the controller effect.

[0069] However, under the condition of formula (1), formula (12) is difficult to solve analytically, so an optimization problem is constructed for numerical solution, as shown in formula (13).

[0070]

[0071] Ultimately, each step of the assembly process simulator requires a given end-of-line pose of the robot arm. Iteratively solve the above optimization problem. In order to understand the operation process of the simulator, the calculation flow chart of the assembly simulator is as follows Figure 5 As shown. At control step t, the assembly process single-step simulator accepts the output from the user-defined assembly control strategy Iterative optimization is used to find the system stable state ( F P , M P , F S , M S ) and output, the user-defined assembly control strategy can execute control according to the system state, thereby changing the control action at time t+1 The optimizer at time t+1 uses the system state at time t as the initial solution, as the system state does not change significantly after a single control step. To ensure both rapid and accurate simulation calculations, a global optimization algorithm is used for the first few steps of the assembly simulation, followed by a gradient-based optimization algorithm.

[0072] The embodiment of the present application can utilize the proposed mechanical modeling method to construct an easily deployable assembly simulator, which can analyze the relationship between the system's posture error and force response in real time, and has significant significance for the design and verification of the controller.

[0073] In step S104, based on the force-position mapping model of suction cup deformation and the force-position mapping model of shaft-hole contact, a compliant control strategy for the flexible grasping shaft-hole assembly process is designed, and the compliant control strategy is verified using a numerical simulator to obtain the final assembly control result of the flexible grasping shaft assembly process.

[0074] Among them, the embodiment of the present application can design a high-compliance control strategy that takes into account the flexible deformation model of the suction cup based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and use the constructed simulator to verify the control effect to obtain the final assembly control result of the flexible grasping shaft assembly process. Compared with FBCC (feature-based compliance control strategy), it achieves a more flexible control effect.

[0075] Optionally, in one embodiment of the present application, based on the force-position mapping model of suction cup deformation and the force-position mapping model of shaft-hole contact, a compliant control strategy for the flexible grasping shaft-hole assembly process is designed, including: based on the force-position mapping model of suction cup deformation and the force-position mapping model of shaft-hole contact, using a preset force system translation theorem to design functions to respectively estimate the force and torque acting on the end point of the suction cup and the force and torque acting on the center of the shaft insertion depth; inputting the force and torque acting on the end point of the suction cup into the inverse model of the suction cup force-position model to generate the actual deformation of the suction cup, and converting the actual deformation of the suction cup into a four-dimensional incremental motion using a preset ratio; inputting the force and torque acting on the center of the shaft insertion depth into a second-order admittance controller to output a six-dimensional incremental motion; integrating the four-dimensional incremental motion and the six-dimensional incremental motion to generate an incremental motion control quantity that meets preset expected conditions, and controlling the assembly of the flexible grasping shaft assembly process according to the incremental motion control quantity that meets the preset expected conditions, thereby obtaining a compliant control strategy for the flexible grasping shaft-hole assembly process.

[0076] Among them, the control strategy architecture of the embodiment of the present application is as follows Figure 6 As shown. The assembly control strategy is based on the F read by the robot end force sensor. F and M F , and finally output the control quantity to the robot's six-dimensional position controller to control the robot to perform insertion motion.

[0077] First, the F read in the environment F and M F , the functions Trans1(F,M) and Trans2(F,M) are designed by the force translation theorem to estimate the end point O of the suction cup respectively. S Force torque and the force at the center of the shaft insertion depth torque Its mathematical expression is shown in formula (14).

[0078]

[0079] in, To utilize z t Estimated depth of shaft insertion into the hole.

[0080] Considering that the movement of the robot arm should conform to the flexible deformation of the suction cup, thereby reducing the deformation stress of the suction cup, the control module 1 will and Input the inverse model of the suction cup force-position model to estimate its deformation And it is converted into the desired four-dimensional incremental motion of the robot arm (Δx1, Δy1, Δα1, Δβ1) through the proportional link, and its flexible posture adjustment center is the end point O of the suction cup S .

[0081] Considering that the robot arm should make a compliant response to the actual contact between the shaft holes, thereby reducing the contact force and the degree of jamming, the control module 2 will and The second-order admittance controller is input and outputs the desired six-dimensional incremental motion of the robot arm (Δx2, Δy2, Δz2, Δα2, Δβ2, Δγ2), and its compliant posture adjustment center is the center point of the axis insertion depth.

[0082] Since the desired compliant motion attitude adjustment centers output by the two control modules are different and are different from the TCP point at the end of the robot arm, they cannot be directly added and transmitted to the robot arm incremental position controller. Instead, they should be adjusted accordingly according to the different attitude adjustment centers. Therefore, the design module Mix() integrates the outputs of the two control modules, and its formula is shown in (15).

[0083]

[0084] The final desired incremental motion control amount (Δx C ,Δy C ,Δz C ,Δα C ,Δβ C ,Δγ C ) forms the absolute position control value of the robot arm through the unit integrator (x c ,y c ,z c ,α c ,β c ,γ c ) inputs the robot position controller to provide support for generating the final control results.

[0085] Figure 7 A comparison diagram of the force response curves generated by the control effect of the compliant method designed in this application in the simulator and the control effect of FBCC is given (the solid line is the compliant method designed in this application). It can be seen that the proposed method eliminates the posture error between the shaft and the hole more quickly and achieves a smoother assembly effect.

[0086] According to the assembly mechanics modeling method of the flexible gripping shaft assembly process proposed in the embodiment of the present application, mathematical modeling is performed on the two sets of force and posture mapping relationships existing in the assembly system of the flexible gripping shaft. Mathematical models of the actual deformation of the flexible suction cup and the force and torque received by its end, and mathematical models of the actual contact force and torque generated between the shaft and the hole due to position and posture errors are constructed respectively. Subsequently, based on the force system translation theorem, a quantitative relationship between the shaft-hole contact force / torque and the deformation force / torque received by the suction cup can be constructed, and based on the numerical optimization method, the above quantitative relationship can be solved, thereby solving the shaft-hole posture error, the actual deformation of the suction cup, and the actual contact force of the shaft hole at each moment of the entire process of the flexible gripping shaft-hole assembly process. Furthermore, given the posture error of the shaft hole during initial assembly, the above method can be used to perform mechanical simulation of the assembly process to form a numerical simulator for the assembly process. Furthermore, this patent also designs a high-compliance control strategy that considers the flexible deformation model of the suction cup and verifies the control effect using a constructed simulator. Compared with FBCC (feature-based compliance control strategy), it achieves a more compliant control effect. This solves the problem that the related art still lacks research and discussion on the mechanical modeling of shaft-hole assembly for flexible gripping, making it difficult to assist in the design of compliant control strategies.

[0087] Next, an assembly mechanics modeling device for the flexible gripping shaft assembly process proposed in an embodiment of the present application will be described with reference to the accompanying drawings.

[0088] Figure 8 It is a structural schematic diagram of the assembly mechanics modeling device of the flexible gripping shaft assembly process in an embodiment of the present application.

[0089] like Figure 8 As shown, the assembly mechanics modeling device 10 for the flexible gripping shaft assembly process includes: a first building module 100 , a second building module 200 , a calculation module 300 and an assembly control module 400 .

[0090] Specifically, the first construction module 100 is used to construct a force-position mapping model of suction cup deformation based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup.

[0091] The second construction module 200 is used to construct a force-position mapping model of the shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque.

[0092] The calculation module 300 is used to calculate the actual values ​​of the shaft hole posture error, the actual deformation of the suction cup and the actual contact force of the shaft hole at each moment in the flexible grasping shaft hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft hole contact, and construct a numerical simulation method for the flexible grasping shaft hole assembly process according to the actual values, so as to use the numerical simulation method to construct a numerical simulator for the flexible grasping shaft hole assembly process.

[0093] The assembly control module 400 is used to design a compliant control strategy for the flexible gripping shaft-hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and to verify the compliant control strategy using a numerical simulator to obtain the final assembly control result of the flexible gripping shaft assembly process.

[0094] Optionally, in one embodiment of the present application, the first building module 100 includes: a first computing unit and a first building unit.

[0095] The first calculation unit is used to calculate the deformation amount of the force and torque applied to the end of the flexible suction cup based on the deformation characteristics and cylindrical characteristics of the flexible suction cup, and algebraically superimpose the deformation amount to generate a superimposed value of the deformation amount.

[0096] The first construction unit is used to obtain the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque by using superimposed numerical values, and to construct a force-position mapping model of the suction cup deformation according to the mathematical relationship.

[0097] Optionally, in one embodiment of the present application, the second building module 200 includes: a second computing unit and a second building unit.

[0098] The first calculation unit is used to divide the shaft hole into at least one discrete element at each height section, and calculate the force and torque generated by the local pressure and friction force on the at least one discrete element in the shaft coordinate system.

[0099] The second construction unit is used to numerically integrate the forces and moments to generate corresponding shaft-hole contact forces and moments, and to construct a force-position mapping model of shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact forces and moments.

[0100] Optionally, in one embodiment of the present application, the calculation module 300 includes: an acquisition unit and a generation unit.

[0101] The acquisition unit is used to obtain the initial position error of the shaft hole before the flexible grasping shaft hole is assembled.

[0102] The generation unit is used to assemble the flexible gripping shaft hole based on the initial posture error of the shaft hole using a preset control strategy until the shaft is inserted into the hole, generate the force and torque curve of the flexible gripping shaft hole, and build a numerical simulator for the flexible gripping shaft hole assembly process based on the force and torque curve of the flexible gripping shaft hole.

[0103] Optionally, in one embodiment of the present application, the assembly control module 400 includes: an estimation unit, an input unit, an output unit, and an integration unit.

[0104] Among them, the estimation unit is used to estimate the force and torque acting on the end point of the suction cup and the force and torque acting on the center of the shaft insertion depth based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and uses the preset force system translation theorem to design functions.

[0105] The input unit is used to input the force and torque exerted on the end point of the suction cup into the inverse model of the suction cup force-position model to generate the actual deformation of the suction cup, and convert the actual deformation of the suction cup into four-dimensional incremental motion using a preset ratio.

[0106] The output unit is used to input the force and torque received at the center of the shaft insertion depth into the second-order admittance controller to output six-dimensional incremental motion.

[0107] The integration unit is used to integrate four-dimensional incremental motion and six-dimensional incremental motion to generate incremental motion control quantities that meet preset expected conditions, and control the assembly process of the flexible gripping shaft according to the incremental motion control quantities that meet the preset expected conditions to obtain a compliant control strategy for the flexible gripping shaft hole assembly process.

[0108] It should be noted that the above explanation of the embodiment of the assembly control method for the flexible gripping shaft assembly process is also applicable to the assembly control device for the flexible gripping shaft assembly process of this embodiment, and will not be repeated here.

[0109] According to the assembly mechanics modeling device for the flexible gripping shaft assembly process proposed in the embodiment of the present application, a mechanical model of the flexible gripping shaft-hole assembly system is constructed, and the two key mechanical links are modeled, which can well guide the design of the compliant control strategy of the flexible gripping shaft-hole assembly system. In addition, the embodiment of the present application constructs an easy-to-deploy assembly simulator that can analyze the relationship between the system's posture error and force response in real time, which has significant significance for the design and verification of the controller. The constructed simulator is used to verify the control effect, and compared with FBCC (feature-based compliant control strategy), it achieves a more compliant control effect. Therefore, it solves the problem that the related technology for the mechanical modeling of flexible gripping shaft-hole assembly is still lacking in research and discussion, and it is difficult to assist in the design of a compliant control strategy.

[0110] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0111] A memory 901 , a processor 902 , and a computer program stored in the memory 901 and executable on the processor 902 .

[0112] When the processor 902 executes the program, the assembly mechanics modeling method for the flexible gripping shaft assembly process provided in the above embodiment is implemented.

[0113] Furthermore, the electronic device further includes:

[0114] The communication interface 903 is used for communication between the memory 901 and the processor 902 .

[0115] The memory 901 is used to store computer programs that can be run on the processor 902 .

[0116] The memory 901 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0117] If the memory 901, processor 902, and communication interface 903 are implemented independently, the communication interface 903, memory 901, and processor 902 can be connected to each other via a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 9 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0118] Optionally, in a specific implementation, if the memory 901, the processor 902 and the communication interface 903 are integrated on a chip, the memory 901, the processor 902 and the communication interface 903 can communicate with each other through an internal interface.

[0119] The processor 902 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0120] This embodiment further provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the assembly mechanics modeling method for the flexible gripping shaft assembly process as described above is implemented.

[0121] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0122] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this application, "N" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0123] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing a custom logical function or process step, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed in a different order than shown or discussed, including performing functions in a substantially simultaneous manner or in a reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application pertain.

[0124] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program can be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing it in other suitable ways as necessary, and then storing it in a computer memory.

[0125] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiment, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used to implement: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0126] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0127] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0128] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for modeling assembly mechanics of a flexible gripping shaft assembly process, characterized in that: The following steps are involved: Based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup, a force-position mapping model of the suction cup deformation is constructed. Based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque, a force-position mapping model of shaft-hole contact is constructed; Based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, the actual values ​​of the shaft-hole posture error, the actual deformation of the suction cup, and the actual contact force of the shaft-hole at each moment in the flexible grasping shaft-hole assembly process are calculated, and a numerical simulation method of the flexible grasping shaft-hole assembly process is constructed based on the actual values, so as to construct a numerical simulator of the flexible grasping shaft-hole assembly process using the numerical simulation method; Based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, a compliant control strategy for the flexible grasping shaft-hole assembly process is designed, and the compliant control strategy is verified using the numerical simulator to obtain the final assembly control result of the flexible grasping shaft assembly process, wherein the compliant control strategy for the flexible grasping shaft-hole assembly process is designed based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, including: based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, using the preset force system translation theorem to design functions to respectively estimate the force and torque acting on the end point of the suction cup and the center of the shaft insertion depth. The force and torque received by the end point of the suction cup are input into the inverse model of the suction cup force-position model to generate the actual deformation of the suction cup, and the actual deformation of the suction cup is converted into a four-dimensional incremental motion using a preset ratio; the force and torque received by the shaft when inserted into the depth center are input into a second-order admittance controller to output a six-dimensional incremental motion; the four-dimensional incremental motion and the six-dimensional incremental motion are integrated to generate an incremental motion control quantity that meets the preset expected conditions, and the assembly process of the flexible gripping shaft is controlled according to the incremental motion control quantity that meets the preset expected conditions, so as to obtain a compliant control strategy for the flexible gripping shaft hole assembly process.

2. The method according to claim 1, characterized in that The force-position mapping model of the suction cup deformation is constructed based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup, including: Based on the deformation characteristics and cylindrical characteristics of the flexible suction cup, calculating the deformation amount of the force and the moment applied to the end of the flexible suction cup, and algebraically superimposing the deformation amounts to generate a superimposed value of the deformation amount; The superimposed values ​​are used to obtain a mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque, and a force-position mapping model of the suction cup deformation is constructed based on the mathematical relationship.

3. The method according to claim 1, characterized in that The force-position mapping model of the shaft-hole contact is constructed based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque, including: Divide the shaft hole into at least one discrete element at each height section, and calculate the force and torque generated by the local pressure and friction force on the at least one discrete element in the shaft coordinate system; The force and the torque are numerically integrated to generate the corresponding shaft-hole contact force and torque, and a force-position mapping model of the shaft-hole contact is constructed based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque.

4. The method according to claim 1, wherein The numerical simulator for constructing the flexible gripping shaft hole assembly process using the numerical simulation method includes: Obtain the initial position error of the shaft hole before flexible grasping shaft hole assembly; Based on the initial posture error of the shaft hole, the flexible gripping shaft hole is assembled using a preset control strategy until the shaft is inserted into the hole, and the force and torque curve of the flexible gripping shaft hole is generated. Based on the force and torque curve of the flexible gripping shaft hole, a numerical simulator of the flexible gripping shaft hole assembly process is constructed.

5. An assembly mechanics modeling device for a flexible gripping shaft assembly process, characterized in that: include: The first building module is used to build a force-position mapping model of the suction cup deformation based on the mathematical relationship between the real-time deformation of the flexible suction cup and the force and torque applied to the end of the flexible suction cup; The second construction module is used to construct a force-position mapping model of the shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque; a calculation module for calculating the actual values ​​of the shaft hole posture error, the actual deformation of the suction cup, and the actual contact force of the shaft hole at each moment in the flexible gripping shaft hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft hole contact, and constructing a numerical simulation method for the flexible gripping shaft hole assembly process according to the actual values, so as to construct a numerical simulator for the flexible gripping shaft hole assembly process using the numerical simulation method; An assembly control module is used to design a compliant control strategy for the flexible grasping shaft-hole assembly process based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact, and to verify the compliant control strategy using the numerical simulator to obtain the final assembly control result of the flexible grasping shaft assembly process, wherein the assembly control module includes: an estimation unit, used to estimate the force and torque acting on the end point of the suction cup and the force and torque acting on the center of the shaft insertion depth respectively based on the force-position mapping model of the suction cup deformation and the force-position mapping model of the shaft-hole contact using a preset force system translation theorem design function; an input unit, used to input the force and torque acting on the end point of the suction cup The force and the torque are input into the inverse model of the suction cup force-position model to generate the actual deformation of the suction cup, and the actual deformation of the suction cup is converted into a four-dimensional incremental motion using a preset ratio; an output unit is used to input the force and the torque received by the shaft when inserted into the depth center into a second-order admittance controller to output a six-dimensional incremental motion; an integration unit is used to integrate the four-dimensional incremental motion and the six-dimensional incremental motion to generate an incremental motion control quantity that meets the preset expected conditions, and the assembly process of the flexible grasping shaft is controlled according to the incremental motion control quantity that meets the preset expected conditions, so as to obtain a compliant control strategy for the flexible grasping shaft hole assembly process.

6. The device according to claim 5, characterized in that The first building block includes: a first calculation unit, configured to calculate a deformation amount of the end of the flexible suction cup caused by the force and the moment based on the deformation characteristics and the cylindrical characteristics of the flexible suction cup, and algebraically superimpose the deformation amounts to generate a superimposed value of the deformation amount; The first construction unit is used to obtain the mathematical relationship between the real-time deformation of the flexible suction cup and the force and the torque by using the superimposed numerical value, and to construct a force-position mapping model of the suction cup deformation according to the mathematical relationship.

7. The device according to claim 5, characterized in that The second building block includes: A first calculation unit is used to divide the shaft hole into at least one discrete element at each height section, and calculate the force and torque generated by the local pressure and friction force on the at least one discrete element in the shaft coordinate system; The second construction unit is used to numerically integrate the force and the torque to generate the corresponding shaft-hole contact force and torque, and construct a force-position mapping model of the shaft-hole contact based on the mathematical relationship between the shaft-hole posture error and the corresponding shaft-hole contact force and torque.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the assembly mechanics modeling method for the flexible gripping shaft assembly process according to any one of claims 1 to 4.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the assembly mechanics modeling method for the flexible gripping shaft assembly process according to any one of claims 1 to 4.

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