A method, system, device, and medium for monitoring integrated linear servo joint state

Abstract

The application provides a method, system, device and medium for monitoring the state of an integrated linear servo joint. The method obtains effective contact deformation by constructing a nonlinear effective deformation function, calculates discrete equivalent contact stiffness based on a multi-turn thread deformation coordination equation, and packages it as a bivariate orthogonal grid interpolation surface. During operation, the instantaneous friction coefficient is determined from the preset friction-velocity mapping relationship according to the real-time tangential sliding speed. The equivalent contact stiffness is obtained on the interpolation surface by inputting the current effective contact deformation and the instantaneous friction coefficient. The nonlinear time-varying characteristics of wear degradation, asymmetric load and contact stiffness are coupled into a unified dynamic solving framework, so that small changes in the wear state can be reflected in real time as differences in contact elastic force. The method takes the circumferential friction shear force component and the axial friction thrust component as external excitation, and finally constructs a multi-source fault evolution mapping graph to obtain the state monitoring result.

Description

Technical Field

[0001] This invention belongs to the field of precision manufacturing technology, specifically relating to a method, system, device, and medium for monitoring the status of an integrated linear servo joint. Background Technology

[0002] Electromechanical actuation systems, due to their high power density and ease of control, have been widely used in aerospace and high-end equipment fields. With the evolution of structural design, the "integrated linear servo joint" that highly integrates frameless motors and reverse planetary roller screws (IPRS) has become the mainstream trend. This structure eliminates the traditional external reduction gearbox and long flexible drive shaft, integrating the motor rotor, rotating nut, and positioning gear into a single rigid rotating component.

[0003] In recent years, preliminary progress has been made in the coupled excitation dynamics modeling of planetary roller screws. For example, related studies have constructed a dynamic load distribution model that integrates gear meshing excitation and thread deformation, revealing the coupling influence mechanism of gear pair meshing excitation and roller revolution inertia force on the dynamic load of the thread pair. Meanwhile, the existing published patent CN120449352A discloses a gear-thread coupled excitation dynamics modeling method for planetary roller screws, which focuses on the modeling accuracy of dynamic load distribution and does not extend to the signal transmission mechanism for condition monitoring and the extraction of weak fault features.

[0004] For early, hidden wear diagnosis of core actuators with deep cavities, such as helical pairs, existing technologies still face the following three major technical bottlenecks:

[0005] Firstly, the fully enclosed structure makes it difficult to extract low-frequency impact signals. The integrated servo joint has a compact structure and high-protection sealing, making it difficult to place contact sensors inside the deep cavity. Current monitoring methods mostly blindly search for low-frequency features on the external shell, failing to realize that under the rigid structure of the same body, the internal low-frequency impact energy is dynamically mapped and modulated onto the high-frequency characteristic signal of the positioning gear. Low-frequency search often fails because the energy is weak and masked by macroscopic mechanical noise.

[0006] Secondly, there is a lack of support from the real-world friction decoupling and asymmetric evolution mechanism. Traditional electromechanical models often employ a one-dimensional pure torsional approximation, which fails to decouple the total dynamic friction force at the helical contact interface into axial thrust and circumferential shear force on a three-dimensional spatial scale. Furthermore, existing models are mostly limited to the axisymmetric uniform distribution assumption, leading to "symmetric cancellation" of the low-frequency vibration vectors excited by each roller in theoretical calculations, thus failing to accurately reproduce the burst mechanism of the fundamental frequency characteristic of internal faults.

[0007] Third, the strong nonlinearity makes dynamic simulation solutions prone to divergence. A realistic full-life wear degradation analysis must incorporate a complex contact model that includes time-varying gap dead zones and frictional softening effects. In conventional implicit integration, high-frequency explicit calls to multi-turn thread deformation compatibility equations not only induce Jacobian matrix singularities, easily leading to high-frequency numerical chatter and deadlock, but also result in the computational dimensionality curse of scan simulations.

[0008] Therefore, this application anticipates a state monitoring method based on the decoupling of integrated linear servo joint dynamics mapping and frequency domain characteristics. Summary of the Invention

[0009] To address the challenges in diagnosing hidden internal wear and extracting weak external signal features in existing integrated linear servo joints, this invention provides a method, system, device, and medium for monitoring the status of integrated linear servo joints.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] In a first aspect, embodiments of this disclosure provide a method for monitoring the state of an integrated linear servo joint, comprising the following steps:

[0012] Step S1: Construct the full-link multibody dynamics topology architecture of the integrated linear servo joint, and establish an integrated dynamics mapping model based on the full-link multibody dynamics topology architecture;

[0013] Step S2: Extract the degradation characteristics of the spiral interface based on the integrated dynamic mapping model, set the wear depth parameters characterizing different service stages, construct the nonlinear effective deformation function of the contact interface by combining the time-varying asymmetric off-center load distribution model that varies with the nut rotation angle, and obtain the effective contact deformation amount based on the nonlinear effective deformation function.

[0014] Step S3: Pre-traverse the effective contact deformation amount and the preset friction coefficient range. For each set of effective contact deformation amount and friction coefficient, calculate discrete equivalent contact stiffness scatter data based on the multi-turn thread deformation compatibility equation, and project and encapsulate the discrete equivalent contact stiffness scatter data into a bivariate orthogonal mesh interpolation surface.

[0015] Step S4: Based on the real-time tangential sliding velocity, determine the instantaneous friction coefficient through a preset friction-velocity mapping relationship; using the effective contact deformation at the current moment and the instantaneous friction coefficient as input, perform interpolation on the bivariate orthogonal mesh interpolation surface to obtain the instantaneous equivalent contact stiffness; within the time step of the implicit integration of dynamics, calculate the contact elastic force according to Hooke's law using the instantaneous equivalent contact stiffness and the effective contact deformation, and feed the contact elastic force back to the system dynamic equation for implicit iterative solution to obtain the instantaneous motion state of the servo joint at the current time step;

[0016] Step S5: Based on the velocity information in the instantaneous motion state, synthesize the relative sliding velocity in the tangential direction of the conjugate contact surface, and extract the local normal unit vector of the helical contact surface in the integrated linear servo joint; project the contact elastic force along the direction of the local normal unit vector to obtain the total normal contact force vector; based on the total normal contact force vector and the relative sliding velocity, use a regularized friction model to generate a friction excitation force vector, and perform three-dimensional spatial orthogonal decoupling of the friction excitation force vector with the normal, circumferential and axial directions as references to obtain the circumferential friction shear force component and the axial friction thrust component respectively;

[0017] Step S6: The circumferential friction shear force component and the axial friction thrust component are used as external excitations and substituted into the system differential equations corresponding to the integrated dynamic mapping model for numerical solution to obtain the dynamic response of the servo joint; along the helical path of the helical transmission contact interface, the physical quantity time history data of each discrete contact point in the dynamic response are spatially synchronously sampled and reconstructed to generate the spatiotemporal distribution result of the contact interface state.

[0018] Step S7: Preset monitoring target points on the integrated linear servo joint. Based on the spatial coordinates of the monitoring target points, extract the vibration response signal at the monitoring target points from the spatiotemporal distribution results of the contact interface. Perform high-frequency carrier envelope demodulation analysis on the response signal to obtain the fault characteristic frequency. Construct a multi-source fault evolution mapping map based on the fault characteristic frequency. Obtain the state monitoring results of the integrated linear servo joint based on the multi-source fault evolution mapping map.

[0019] Furthermore, the full-link multibody dynamics topology includes: a coordinate system for the translational and torsional degrees of freedom of a frameless motor, an integrated positioning gear, and a reverse planetary roller screw mechanism;

[0020] The rotor, rotating nut, and positioning gear of the frameless motor of the integrated linear servo joint are configured as a rigid rotating component of the same body. An integrated dynamic mapping model is constructed based on the translational and torsional degrees of freedom coordinate system of the rigid rotating component of the same body and the asymmetric off-center load wear parameters of the time-varying rotation angle of the rotating nut.

[0021] Furthermore, obtaining the effective contact deformation includes:

[0022] Calculate the initial contact deformation ,include:

[0023] ;

[0024] In the formula, For any pair of conjugate transmission components Theoretical geometric interference quantity in the normal direction; This is a parameter for the depth of wear and loss. This is the coefficient for asymmetric wear under eccentric loading. For the first The initial circumferential mounting phase of each roller; The angular velocity of the rotating nut;

[0025] Regarding the initial contact deformation Make a judgment, if If the value is greater than 0, then it represents the effective contact deformation after eliminating wear gaps, indicating that the conjugate components are in a true contact state and can transmit normal elastic force and damping force. When the value is ≤0, it is determined that the contact pair is completely inside the wear gap, and the normal contact elastic force and damping force are forced to zero. At this moment, in the system dynamic equation, it is manifested as the discontinuous disappearance and recovery of the contact force, introducing the alternating impact nonlinear behavior when crossing the gap boundary and transforming it into a time-varying impact excitation source in the system differential equation system.

[0026] Furthermore, the generation of the bivariate orthogonal mesh interpolation surface includes the following steps:

[0027] Based on the damped trust region nonlinear optimization algorithm, the deformation coordination iteration of the thread load distribution of the rotating nut is performed to obtain the equivalent tangential and normal meshing stiffness in discrete scatter form under non-uniform stress state, which is used as discrete equivalent contact stiffness scatter data.

[0028] Extract the one-dimensional deformation coordinates and one-dimensional friction coefficient coordinates from the discrete equivalent contact stiffness scatter data, generate a two-dimensional orthogonal mesh, and generate a two-dimensional orthogonal mesh manifold based on the two-dimensional orthogonal mesh through tensor product;

[0029] The stiffness matrix at the orthogonal grid nodes of the two-dimensional orthogonal grid manifold is evaluated by the original scatter interpolator, and the evaluation results are encapsulated to generate a bivariate orthogonal grid interpolation surface based on memory address addressing.

[0030] Furthermore, obtaining the circumferential frictional shear force component and the axial frictional thrust component includes the following steps:

[0031] Extract the local normal unit vector of the helical contact surface of the integrated linear servo joint, and obtain the geometric projection coefficient of the helical tangential direction based on the local normal unit vector. When projecting the contact elastic force along the local normal unit vector direction, the contact elastic force is divided by the geometric projection coefficient. Inversely determine the instantaneous normal total contact vector ;

[0032] Extract the relative sliding velocity in the tangential direction of the conjugate contact surface of the integrated linear servo joint. The relative sliding speed Substituting into the Stribeck model yields the real-time sliding friction coefficient. ;

[0033] Based on the instantaneous total normal contact force Relative sliding speed and real-time sliding friction coefficient Construct a regularized frictional excitation force vector containing an exponential starting slope and a hyperbolic tangent direction function. :

[0034] ;

[0035] In the formula, To determine the start-up time constant for the gentle slope, This is the velocity tolerance band constant;

[0036] Using the helix angle, which characterizes the helical morphology, as a spatial transformation operator, the frictional excitation force vector is transformed based on the spatial transformation operator. By orthogonally decoupling the three-dimensional space with the normal, circumferential and axial directions as references, the circumferential friction shear force component and the axial friction thrust component are obtained.

[0037] Furthermore, obtaining the spatiotemporal distribution results of the contact interface states includes the following steps:

[0038] Using the circumferential friction shear force component and the axial friction thrust component as external excitations, and combining the load-stiffness hardening effect, a system of system differential equations corresponding to the integrated dynamic mapping model is constructed. The system of system differential equations is based on the effective contact deformation. The determination result is used to switch the contact and disengagement states of the elastic force and damping force of each contact pair of the screw drive in each time step, as the dynamic response of the servo joint.

[0039] An implicit integrator is used to perform adaptive variable step-size numerical solution of the differential equations of the system, and the time history data of physical quantities at each discrete position on the contact interface of the screw drive are obtained.

[0040] Along the helical path of the helical transmission contact interface, the physical quantity time history data of all discrete contact points are spatially synchronously sampled and reconstructed to generate the spatiotemporal distribution result of the contact interface state; the spatiotemporal distribution result includes a spatiotemporal four-dimensional dataset of contact force, sliding speed and contact state identifier.

[0041] Furthermore, obtaining the status monitoring results includes the following steps:

[0042] A preset monitoring target point is set on the housing or positioning end of the integrated linear servo joint. Based on the spatial coordinates of the monitoring target point, the broadband vibration response signal at the target point position is extracted by interpolation from the spatiotemporal distribution results of the state.

[0043] Based on the broadband vibration response signal, the high-frequency characteristic frequency of the positioning gear is locked, and the broadband vibration response signal is subjected to envelope demodulation analysis centered on the high-frequency carrier frequency band to extract the low-frequency impact characteristics caused by wear gap impact.

[0044] Based on the low-frequency impact characteristics, a multi-source fault evolution mapping map based on a single monitoring target is constructed. Based on the characteristic frequency energy changes and trend characteristics in the multi-source fault evolution mapping map, the state monitoring results of the integrated linear servo joint are obtained.

[0045] In a second aspect, embodiments of this disclosure provide a system for monitoring the state of an integrated linear servo joint, comprising:

[0046] The preprocessing unit is configured to construct a full-link multibody dynamics topology architecture for an integrated linear servo joint, and to establish an integrated dynamics mapping model based on the full-link multibody dynamics topology architecture.

[0047] The initialization unit is configured to extract the degradation characteristics of the spiral interface based on the integrated dynamic mapping model, set the wear depth parameters characterizing different service stages, construct the nonlinear effective deformation function of the contact interface by combining the time-varying asymmetric off-center load distribution model that varies with the nut rotation angle, and obtain the effective contact deformation amount based on the nonlinear effective deformation function.

[0048] The offline unit is configured to pre-traverse the effective contact deformation amount and the preset friction coefficient range, calculate discrete equivalent contact stiffness scatter data based on the multi-turn thread deformation compatibility equation for each set of effective contact deformation amount and friction coefficient, and project and encapsulate the discrete equivalent contact stiffness scatter data into a bivariate orthogonal mesh interpolation surface.

[0049] The computing unit is configured to determine the instantaneous friction coefficient based on the real-time tangential sliding velocity through a preset friction-velocity mapping relationship; to perform interpolation on the bivariate orthogonal mesh interpolation surface using the effective contact deformation and the instantaneous friction coefficient as input, thereby obtaining the instantaneous equivalent contact stiffness; and to calculate the contact elastic force according to Hooke's law from the instantaneous equivalent contact stiffness and the effective contact deformation within the time step of the implicit integration of dynamics, and to feed the contact elastic force back to the system dynamic equations for implicit iterative solution, thereby obtaining the instantaneous motion state of the servo joint at the current time step.

[0050] The decoupling unit is configured to synthesize the relative sliding velocity in the tangential direction of the conjugate contact surface based on the velocity information in the instantaneous motion state, extract the local normal unit vector of the helical contact surface in the integrated linear servo joint; project the contact elastic force along the direction of the local normal unit vector to obtain the normal total contact force vector; based on the normal total contact force vector and the relative sliding velocity, generate the friction excitation force vector using a regularized friction model, and perform three-dimensional spatial orthogonal decoupling of the friction excitation force vector with the normal, circumferential and axial directions as references to obtain the circumferential friction shear force component and the axial friction thrust component, respectively.

[0051] The reconstruction unit takes the circumferential friction shear force component and the axial friction thrust component as external excitations, substitutes them into the system differential equations corresponding to the integrated dynamic mapping model for numerical solution, and obtains the dynamic response of the servo joint; along the helical path of the helical transmission contact interface, it performs spatial synchronous sampling and reconstruction of the physical quantity time history data of each discrete contact point in the dynamic response, and generates the spatiotemporal distribution result of the contact interface state;

[0052] The output unit is configured to preset monitoring target points on the integrated linear servo joint, extract the vibration response signal at the monitoring target point from the spatiotemporal distribution result of the state of the contact interface according to the spatial coordinates of the monitoring target point; perform high-frequency carrier envelope demodulation analysis on the response signal to obtain the fault characteristic frequency, construct a multi-source fault evolution mapping map based on the fault characteristic frequency, and obtain the state monitoring result of the integrated linear servo joint based on the multi-source fault evolution mapping map.

[0053] In a third aspect, embodiments of this disclosure provide an electronic device, characterized in that the electronic device comprises:

[0054] At least one processor; and,

[0055] The memory is communicatively connected to the at least one processor; wherein,

[0056] The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method for monitoring the status of the integrated linear servo joint.

[0057] In a fourth aspect, embodiments of this disclosure provide a non-transitory computer-readable storage medium, characterized in that the non-transitory computer-readable storage medium stores computer instructions for causing the computer to execute the method for monitoring the state of an integrated linear servo joint.

[0058] Compared with the prior art, the present invention has the following beneficial technical effects:

[0059] This invention provides a method, system, device, and medium for monitoring the state of an integrated linear servo joint. The method extracts the degradation characteristics of the helical interface and sets a wear depth parameter. Combined with an asymmetric off-center load distribution model that varies with the nut rotation angle, a nonlinear effective deformation function is constructed to obtain the effective contact deformation. Then, the effective contact deformation and friction coefficient range are pre-traversed, and the discrete equivalent contact stiffness is calculated based on the multi-turn thread deformation compatibility equation and encapsulated as a bivariate orthogonal mesh interpolation surface. During operation, the instantaneous friction coefficient is determined based on the real-time tangential sliding speed using a preset friction-velocity mapping relationship. The equivalent contact stiffness is obtained on the interpolation surface using the current effective contact deformation and the instantaneous friction coefficient as inputs, and the contact elastic force is calculated according to Hooke's law and fed back to the system dynamic equations for implicit iterative solution. This derivation process couples the nonlinear time-varying characteristics of wear degradation, asymmetric off-center load, and contact stiffness into a unified dynamic solution framework, allowing minute changes in the wear state to be reflected in real-time as differences in contact elastic force. Simultaneously, this method uses the circumferential friction shear force component and the axial friction thrust component as external excitations, substituting them into the system differential equations of the integrated dynamic mapping model for numerical solution to obtain the dynamic response of the servo joint. Furthermore, it spatially samples and reconstructs the time histories of physical quantities at each discrete contact point along the helical path, generating the spatiotemporal distribution of the contact interface state. At a preset monitoring target point, it directly extracts the vibration response signal from this spatiotemporal distribution, performs high-frequency carrier envelope demodulation analysis to extract fault characteristic frequencies, and finally constructs a multi-source fault evolution mapping map to obtain the state monitoring results. This derivation chain enables spatiotemporal visualization and fault prediction of the contact state in the non-measurable region within the helical pair, significantly enhancing the comprehensiveness of state monitoring and early warning capabilities. Attached Figure Description

[0060] Figure 1 A flowchart 100 of a method for monitoring the state of an integrated linear servo joint according to an embodiment of the present disclosure is shown;

[0061] Figure 2 The diagram shows the 3D evolution of the equivalent stiffness of the lead screw-roller in the embodiments of this disclosure as a function of deformation and friction coefficient;

[0062] Figure 3 A 3D evolution diagram of the equivalent stiffness of the nut-roller in the embodiments of this disclosure as a function of deformation and friction coefficient is shown.

[0063] Figure 4 The diagram shows the axial vibration displacement response curve of the linear actuator when the system is started in this embodiment of the present disclosure.

[0064] Figure 5 The figure shows the axial vibration displacement response curve of the linear actuator after the system stabilizes in this embodiment of the present disclosure.

[0065] Figure 6 The demodulated spectrum of the axial acceleration envelope at the linear actuator according to an embodiment of this disclosure is shown.

[0066] Figure 7 Figure 1000 illustrates a method apparatus for monitoring the state of an integrated linear servo joint according to an embodiment of the present disclosure. Detailed Implementation

[0067] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] Figure 1 A flowchart 100 of a method for monitoring the state of an integrated linear servo joint according to a first embodiment of this application is shown, as follows: Figure 1 As shown, it includes the following steps:

[0069] In step S101, a full-link multibody dynamics topology architecture for an integrated linear servo joint is constructed, and an integrated dynamics mapping model is established based on the full-link multibody dynamics topology architecture.

[0070] Specifically, the full-link multibody dynamics topology includes: a frameless motor, an integrated positioning gear, and a reverse planetary roller screw mechanism with translational and torsional degrees of freedom coordinate systems;

[0071] The rotor, rotating nut, and positioning gear of the frameless motor of the integrated linear servo joint are configured as a rigid rotating component of the same body. An integrated dynamic mapping model is constructed based on the translational and torsional degrees of freedom coordinate system of the rigid rotating component of the same body and the asymmetric off-center load wear parameters of the time-varying rotation angle of the rotating nut.

[0072] It should be noted that by configuring the frameless motor rotor, rotating nut, and positioning gear as a single rigid rotating component, the long flexible drive shaft and reduction gear stage in the traditional structure are eliminated. Through the integrated physical properties of the single rigid rotating component, it is clarified that the low-frequency alternating impact caused by the wear of the internal helical pair can be mapped and modulated onto the high-frequency characteristic carrier wave of the positioning gear. On this basis, through a rigid spatial transformation matrix, the alternating impact force and torque generated at the helical drive contact interface are equivalently transferred to the dynamic coordinate system of the positioning gear. This equivalent excitation term is embedded into the system dynamic equation of the servo joint, thereby constructing an integrated dynamic mapping model that can describe the quantitative relationship between internal wear excitation and external vibration response.

[0073] Next, proceed to step S102.

[0074] In step S102, the degradation characteristics of the spiral interface are extracted based on the integrated dynamic mapping model, the wear depth parameters characterizing different service stages are set, and the nonlinear effective deformation function of the contact interface is constructed by combining the time-varying asymmetric off-center load distribution model that varies with the nut rotation angle. The effective contact deformation amount is obtained based on the nonlinear effective deformation function.

[0075] Specifically, to break the symmetrical cancellation effect of the internal excitation of the reverse planetary distribution mechanism, an asymmetric off-center load term that varies with the time-varying rotation angle of the nut is superimposed to calculate the initial contact deformation. This approach breaks the symmetrical cancellation effect of excitation forces within a symmetrical planetary distribution mechanism from a fundamental dynamic perspective, realistically reproducing the nonlinear evolution process of alternating impact, and providing a high-fidelity theoretical basis for the generation mechanism of weak early-stage wear signals in deep cavities. The effective contact deformation amount includes:

[0076] Calculate the initial contact deformation ,include:

[0077] ;

[0078] In the formula, For any pair of conjugate transmission components Theoretical geometric interference quantity in the normal direction; This is a parameter for the depth of wear and loss. This is the coefficient for asymmetric wear under eccentric loading. For the first The initial circumferential mounting phase of each roller; The angular velocity of the rotating nut;

[0079] Regarding the initial contact deformation Make a judgment, if If the value is greater than 0, then this value is directly used as the effective contact deformation after eliminating the wear gap, indicating that the conjugate components are in a true contact state and can transmit normal elastic force and damping force. When the value is ≤0, it is determined that the contact pair is completely within the wear gap, and the normal contact elastic force and damping force are forced to zero. At this moment, in the system dynamic equation, the contact force is discontinuously disappearing and recovering, thus introducing the alternating impact nonlinear behavior when crossing the gap boundary. This behavior will be directly transformed into the time-varying impact excitation source in the subsequent system differential equation.

[0080] Next, proceed to step S103.

[0081] In step S103, the effective contact deformation amount and the preset friction coefficient range are traversed in advance. For each set of effective contact deformation amount and friction coefficient, discrete equivalent contact stiffness scatter data are calculated based on the multi-turn thread deformation compatibility equation. The discrete equivalent contact stiffness scatter data are then projected and encapsulated into a bivariate orthogonal mesh interpolation surface.

[0082] Specifically, generating the bivariate orthogonal mesh interpolation surface includes the following steps:

[0083] Based on the damped trust region nonlinear optimization algorithm, the deformation coordination iteration of the thread load distribution of the rotating nut is performed to obtain the equivalent tangential and normal meshing stiffness in discrete scatter form under non-uniform stress state, which is used as discrete equivalent contact stiffness scatter data.

[0084] Extract the one-dimensional deformation coordinates and one-dimensional friction coefficient coordinates from the discrete equivalent contact stiffness scatter data, generate a two-dimensional orthogonal mesh, and generate a two-dimensional orthogonal mesh manifold based on the two-dimensional orthogonal mesh through tensor product;

[0085] The stiffness matrix at the orthogonal grid nodes of the two-dimensional orthogonal grid manifold is evaluated by the original scatter interpolator, and the evaluation results are encapsulated to generate a bivariate orthogonal grid interpolation surface based on memory address addressing.

[0086] Next, proceed to step S104.

[0087] In step S104, the instantaneous friction coefficient is determined based on the real-time tangential sliding velocity through a preset friction-velocity mapping relationship. Using the effective contact deformation and the instantaneous friction coefficient at the current moment as input, interpolation is performed on the bivariate orthogonal mesh interpolation surface to obtain the instantaneous equivalent contact stiffness. Within the time step of the implicit integration of dynamics, the contact elastic force is calculated from the instantaneous equivalent contact stiffness and the effective contact deformation according to Hooke's law, and the contact elastic force is fed back to the system dynamic equation for implicit iterative solution to obtain the instantaneous motion state of the servo joint at the current time step.

[0088] Specifically, the process of solving the contact elastic force is existing technology and is not the core inventive point of this application. When solving the contact elastic force, those skilled in the art can obtain it based on patent 2025120255586 - Integrated linear joint dynamic modeling and dynamic characteristic analysis method, which will not be elaborated in this application.

[0089] Next, proceed to step S105.

[0090] In step S105, the instantaneous motion state of the integrated linear servo joint is obtained (including the rotational angular displacement, angular velocity, axial displacement, and axial velocity of the nut); the local normal unit vector of the helical contact surface in the integrated linear servo joint is extracted; simultaneously, the relative sliding velocity in the tangential direction of the conjugate contact surface is directly synthesized from the velocity information in this instantaneous motion state. The contact elastic force is projected along the direction of the local normal unit vector to obtain the total normal contact force vector; based on the total normal contact force vector and the relative sliding velocity, a regularized friction model is used to generate a friction excitation force vector, and the friction excitation force vector is orthogonally decoupled in three-dimensional space with the normal, circumferential, and axial directions as references to obtain the circumferential friction shear force component and the axial friction thrust component, respectively.

[0091] Specifically, obtaining the circumferential friction shear force component and the axial friction thrust component includes the following steps:

[0092] Based on the rotational angular displacement and axial displacement in the instantaneous motion state, the instantaneous spatial pose of the helical contact surface is determined, the local normal unit vector of the helical contact surface of the integrated linear servo joint is extracted, and the geometric projection coefficient of the helical tangential direction is obtained based on the local normal unit vector. When projecting the contact elastic force along the local normal unit vector direction, the contact elastic force is divided by the geometric projection coefficient. Inversely determine the instantaneous normal total contact vector ;

[0093] The relative sliding velocity in the tangential direction of the conjugate contact surface is synthesized from the angular velocity and axial velocity in the instantaneous motion state. The relative sliding speed Substituting into the Stribeck model yields the real-time sliding friction coefficient. ;

[0094] Based on the instantaneous total normal contact force Relative sliding speed and real-time sliding friction coefficient Construct a regularized frictional excitation force vector containing an exponential starting slope and a hyperbolic tangent direction function. :

[0095] ;

[0096] In the formula, To determine the start-up time constant for the gentle slope, This is the velocity tolerance band constant;

[0097] Using the helix angle, which characterizes the helical morphology, as a spatial transformation operator, the frictional excitation force vector is transformed based on the spatial transformation operator. By orthogonally decoupling the three-dimensional space with the normal, circumferential and axial directions as references, the circumferential friction shear force component and the axial friction thrust component are obtained.

[0098] In this embodiment, to address the problem of one-dimensional approximation and feature symmetry cancellation in traditional models, a thread helix angle is introduced as a spatial transformation operator to strictly orthogonally decouple the total frictional force at the interface into circumferential and axial components.

[0099] Next, proceed to step S106.

[0100] In step S106, the circumferential friction shear force component and the axial friction thrust component are used as external excitations and substituted into the system differential equations corresponding to the integrated dynamic mapping model for numerical solution to obtain the dynamic response of the servo joint; along the helical path of the helical transmission contact interface, the physical quantity time history data of each discrete contact point in the dynamic response are spatially synchronously sampled and reconstructed to generate the spatiotemporal distribution result of the contact interface state.

[0101] Specifically, obtaining the spatiotemporal distribution result of the contact interface includes the following steps:

[0102] Using the circumferential friction shear force component and the axial friction thrust component as external excitations, and combining the load-stiffness hardening effect, a system of system differential equations corresponding to the integrated dynamic mapping model is constructed. The system of system differential equations is based on the effective contact deformation. The determination result is used to switch the contact and disengagement states of the elastic force and damping force of each contact pair of the screw drive in each time step, as the dynamic response of the servo joint.

[0103] An implicit integrator is used to perform adaptive variable step-size numerical solution of the differential equations of the system, and the time history data of physical quantities at each discrete position on the contact interface of the screw drive are obtained.

[0104] Along the helical path of the contact interface of the helical drive, the physical quantity time history data of all discrete contact points are spatially synchronously sampled and reconstructed to generate the spatiotemporal distribution result of the contact interface state; the spatiotemporal distribution result includes a spatiotemporal four-dimensional dataset of contact force, sliding speed and contact state identifier, which fully describes the intensity of the wear gap impact and its spatial propagation path.

[0105] Next, proceed to step S107.

[0106] In step S107, a monitoring target point is preset on the integrated linear servo joint. Based on the spatial coordinates of the monitoring target point, the vibration response signal at the monitoring target point is extracted from the spatiotemporal distribution result of the state of the contact interface. The response signal is subjected to high-frequency carrier envelope demodulation analysis to obtain the fault characteristic frequency. A multi-source fault evolution mapping map is constructed based on the fault characteristic frequency. The state monitoring result of the integrated linear servo joint is obtained based on the multi-source fault evolution mapping map.

[0107] Specifically, obtaining the status monitoring results includes the following steps:

[0108] Obtaining the status monitoring results includes the following steps:

[0109] A preset monitoring target point is set on the housing or positioning end of the integrated linear servo joint. Based on the spatial coordinates of the monitoring target point, the broadband vibration response signal at the target point position is extracted by interpolation from the spatiotemporal distribution results of the state.

[0110] Based on the broadband vibration response signal, the high-frequency characteristic frequency of the positioning gear is locked, and the broadband vibration response signal is subjected to envelope demodulation analysis centered on the high-frequency carrier frequency band to extract the low-frequency impact characteristics caused by wear gap impact.

[0111] Based on the low-frequency impact characteristics, a multi-source fault evolution mapping map based on a single monitoring target is constructed. Based on the characteristic frequency energy changes and trend characteristics in the multi-source fault evolution mapping map, the state monitoring results of the integrated linear servo joint are obtained.

[0112] Furthermore, when performing envelope demodulation analysis centered on the high-frequency carrier band on the broadband vibration response signal, the following steps are included:

[0113] The monitoring target is configured as the lead screw output end of an integrated linear servo joint, and the axial vibration acceleration signal of the monitoring target during the steady-state operation phase is extracted.

[0114] Based on the high-frequency geometric motion characteristics of the upstream positioning gear contained in the axial vibration acceleration signal, and the dynamic mapping and physical aliasing of the nonlinear low-frequency impact of the internal helical pair, a frequency domain feature decoupling technique is used for feature extraction:

[0115] First, based on the Butterworth bandpass filter, within the high-frequency carrier frequency band composed of high-frequency geometric motion characteristics, the positioning characteristic frequency determined by the positioning gear geometric parameters and the corresponding high-order combined harmonics are locked. The internal low-frequency fault impact formed by nonlinear low-frequency impact is modulated to the vicinity of the positioning characteristic frequency, and the carrier signal is extracted.

[0116] The Hilbert transform is performed on the filtered carrier signal to obtain the amplitude envelope. After removing the DC bias component, a high-resolution fast Fourier transform with zero padding is performed to remove the masking effect of the high-frequency positioning component and extract the friction excitation frequency and its higher-order combined harmonics. This enables synchronous tracing of the spiral wear depth based on the response of a single translational node at the execution end.

[0117] The following description, in conjunction with the accompanying drawings and data, further illustrates this embodiment:

[0118] In this embodiment, to construct a full-link multibody dynamics topology, the geometric parameters of the reverse planetary roller screw of the integrated linear servo joint are shown in Table 1, and the characteristic parameters of the frameless motor are shown in Table 2.

[0119] Table 1 Geometric parameters of key components

[0120]

[0121] Table 2

[0122]

[0123] The lead screw, rollers, and nuts are made of GCr15. The equivalent mass, moment of inertia, and support stiffness properties of each component of the system are shown in Table 3.

[0124] Table 3

[0125]

[0126] To achieve multi-band physical aliasing mechanism analysis and characteristic decoupling, the nut rotation speed was set to 3000 rpm. Based on the characteristic parameters of the frameless motor in Table 2, the input nut torque was calculated to be 1420 N·mm. Based on the geometric kinematic relationship in Tables 1 and 2, the theoretical characteristic frequencies of key components of the electromechanical actuation system were calculated in advance, as shown in Table 4. These theoretical characteristic frequencies were precisely calculated from the number of teeth of the positioning gear, the rotation speed of the rigid rotating component, and the transmission structure parameters, specifically including the gear meshing fundamental frequency and its characteristic harmonics. These frequencies will serve as physical reference benchmarks for frequency domain decoupling and diagnosis. In the broadband vibration response signal extracted from the actual monitoring target point, the actual high-frequency characteristic frequencies corresponding to the theoretical frequencies will be locked in through peak search and tolerance matching criteria, thereby determining the high-frequency carrier band center used for envelope demodulation analysis.

[0127] Table 4

[0128]

[0129] In the dynamic solution and signal processing stage, in order to verify the effectiveness of the three-dimensional friction space decoupling, asymmetric wear mechanism and high-pass envelope decoupling algorithm in this invention, the dynamic simulation control and multi-source decoupling parameters of the system are set as shown in Table 5, and the axial heavy load thrust of the system is set to 2000N.

[0130] Table 5

[0131]

[0132] Due to the time-consuming nature of highly nonlinear calculations inherent in tribological models, this embodiment employs offline dimensionality-reduced stiffness mapping. In offline mode, based on the geometric features in Table 1, preset friction coefficient ranges and contact deformation ranges for the tangential sliding of the contact interface are defined. For example... Figure 2 and Figure 3 As shown, bivariate orthogonal mesh interpolation surfaces for the evolution of equivalent contact stiffness with deformation and friction coefficient were generated offline using the multi-turn thread deformation compatibility equation. The figures reveal that the contact stiffness exhibits nonlinear load hardening characteristics with increasing deformation and is also affected by the nonlinear coupling effect of the friction coefficient (friction softening effect). In the subsequent implicit integration solution stage, the bivariate orthogonal mesh interpolation surface was used for mesh addressing, successfully avoiding the explicit inversion of the Jacobian matrix and improving the overall solution efficiency.

[0133] The contact elastic force, circumferential friction shear force component, and axial friction thrust component are injected into an integrated dynamic mapping model, and a full-link time-domain simulation is performed. Numerical integration simulation is conducted under a 2000N load and the parameters in Table 5. The simulation results are as follows: Figure 4 As shown, Figure 4 The axial vibration displacement response curve of the linear actuator during system startup is shown. Within the startup interval of 0~0.1s, the axial displacement Z of the lead screw... s The system smoothly descends from its initial position and converges to its static physical equilibrium position. This process demonstrates that the time ramp and regularized friction excitation force algorithm in this model effectively suppress the initial mechanical imbalance and numerical chatter. After the system enters the stable operation stage, the axial displacement of the lead screw exhibits regular high-frequency alternating fluctuations that include gear excitation and rubbing characteristics.

[0134] The vibration acceleration signal along the lead screw axis of the integrated linear servo joint during the steady-state operation phase is extracted and subjected to a fast Fourier transform to obtain the original high-frequency spectrum, as shown below. Figure 5 As shown, the high-frequency characteristic fundamental frequency f of the gear end is clearly presented in the original high-frequency spectrum. g and its second harmonic 2f gThis result verifies that, under a rigid integrated structure, high-frequency positioning geometric motion characteristics dominate the macroscopic response and constitute an ideal high-frequency analysis range. To remove the masking effect of high-frequency components and extract wear characteristics within the deep cavity, a high-frequency carrier f is locked. g Bandpass filtering was performed on the specified interval, and after removing the DC bias, Hilbert envelope demodulation analysis was performed. The results are as follows: Figure 6 As shown, the frequency peak 2f is clearly highlighted in the demodulated spectrum. spin Among them, f spin Let be the relative rotation frequency of the rollers, i.e., the first-order frictional excitation frequency of the system. This 2f... spin The effective extraction of high-order characteristic peaks directly verifies that the nonlinear frictional impact energy generated by wear at the internal spiral interface can be dynamically mapped and physically modulated onto the high-frequency carrier of the same-body positioning structure. This embodiment objectively demonstrates the effectiveness of the demodulation algorithm of the present invention in overcoming strong background noise masking and separating weak frictional features inside the integrated deep cavity.

[0135] A second embodiment of the present invention also provides a system for monitoring the status of an integrated linear servo joint, comprising:

[0136] The preprocessing unit is configured to construct a full-link multibody dynamics topology architecture for an integrated linear servo joint, and to establish an integrated dynamics mapping model based on the full-link multibody dynamics topology architecture.

[0137] The initialization unit is configured to extract the degradation characteristics of the spiral interface based on the integrated dynamic mapping model, set the wear depth parameters characterizing different service stages, construct the nonlinear effective deformation function of the contact interface by combining the time-varying asymmetric off-center load distribution model that varies with the nut rotation angle, and obtain the effective contact deformation amount based on the nonlinear effective deformation function.

[0138] The offline unit is configured to pre-traverse the effective contact deformation amount and the preset friction coefficient range, calculate discrete equivalent contact stiffness scatter data based on the multi-turn thread deformation compatibility equation for each set of effective contact deformation amount and friction coefficient, and project and encapsulate the discrete equivalent contact stiffness scatter data into a bivariate orthogonal mesh interpolation surface.

[0139] The computing unit is configured to determine the instantaneous friction coefficient based on the real-time tangential sliding velocity through a preset friction-velocity mapping relationship; to perform interpolation on the bivariate orthogonal mesh interpolation surface using the effective contact deformation and the instantaneous friction coefficient as input, thereby obtaining the instantaneous equivalent contact stiffness; and to calculate the contact elastic force according to Hooke's law from the instantaneous equivalent contact stiffness and the effective contact deformation within the time step of the implicit integration of dynamics, and to feed the contact elastic force back to the system dynamic equations for implicit iterative solution, thereby obtaining the instantaneous motion state of the servo joint at the current time step.

[0140] The decoupling unit is configured to synthesize the relative sliding velocity in the tangential direction of the conjugate contact surface based on the velocity information in the instantaneous motion state, extract the local normal unit vector of the helical contact surface in the integrated linear servo joint; project the contact elastic force along the direction of the local normal unit vector to obtain the normal total contact force vector; based on the normal total contact force vector and the relative sliding velocity, generate the friction excitation force vector using a regularized friction model, and perform three-dimensional spatial orthogonal decoupling of the friction excitation force vector with the normal, circumferential and axial directions as references to obtain the circumferential friction shear force component and the axial friction thrust component, respectively.

[0141] The reconstruction unit takes the circumferential friction shear force component and the axial friction thrust component as external excitations, substitutes them into the system differential equations corresponding to the integrated dynamic mapping model for numerical solution, and obtains the dynamic response of the servo joint; along the helical path of the helical transmission contact interface, it performs spatial synchronous sampling and reconstruction of the physical quantity time history data of each discrete contact point in the dynamic response, and generates the spatiotemporal distribution result of the contact interface state;

[0142] The output unit is configured to preset monitoring target points on the integrated linear servo joint, extract the vibration response signal at the monitoring target point from the spatiotemporal distribution result of the state of the contact interface according to the spatial coordinates of the monitoring target point; perform high-frequency carrier envelope demodulation analysis on the response signal to obtain the fault characteristic frequency, construct a multi-source fault evolution mapping map based on the fault characteristic frequency, and obtain the state monitoring result of the integrated linear servo joint based on the multi-source fault evolution mapping map.

[0143] The third embodiment of the present invention also provides an electronic device, the electronic device comprising:

[0144] At least one processor; and,

[0145] The memory is communicatively connected to the at least one processor; wherein,

[0146] The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method for monitoring the state of an integrated linear servo joint according to any of the foregoing embodiments.

[0147] The fourth embodiment of the present invention also provides a non-transitory computer-readable storage medium storing computer instructions for causing the computer to execute the method for monitoring the state of an integrated linear servo joint as described in any of the foregoing embodiments.

[0148] The fifth embodiment of the present invention also provides a computer program product, which includes a computing program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions that, when executed by a computer, cause the computer to perform the method for monitoring the state of an integrated linear servo joint as described in any of the foregoing embodiments.

[0149] Figure 7 The illustration shows a method or device 1000 implementing an embodiment of the present invention. In some embodiments, more or fewer devices may be included than illustrated. In some embodiments, it may be implemented using a single or multiple devices. In some embodiments, it may be implemented using cloud-based or distributed devices.

[0150] like Figure 7 As shown, device 1000 includes a processor 1001 for performing various appropriate operations and processes based on programs and / or data stored in read-only memory (ROM) 1002 or programs and / or data loaded from storage portion 1008 into random access memory (RAM) 1003. Processor 1001 may be a multi-core processor or may contain multiple processors. In some embodiments, processor 1001 may include a general-purpose main processor and one or more special coprocessors, such as a central processing unit (CPU), graphics processing unit (GPU), neural network processor (NPU), digital signal processor (DSP), etc. Various programs and data required for the operation of device 1000 are also stored in RAM 1003. Processor 1001, ROM 1002, and RAM 1003 are interconnected via bus 1004. Input / output (I / O) interface 1005 is also connected to bus 1004.

[0151] The processor and memory described above are used together to execute programs stored in the memory. When the program is executed by a computer, it can implement the methods, steps, or functions described in the above embodiments.

[0152] The following components are connected to I / O interface 1005: an input section 1006 including a keyboard, mouse, touchscreen, etc.; an output section 1007 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 1008 including a hard disk, etc.; and a communication section 1009 including a network interface card such as a LAN card, modem, etc. The communication section 1009 performs communication processing via a network such as the Internet. A drive 1010 is also connected to I / O interface 1005 as needed. A removable medium 1011, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 1010 as needed so that computer programs read from it can be installed into storage section 1008 as needed. Figure 7 The diagram only shows a portion of the components and does not imply that the device 1000 only includes... Figure 7 The components shown.

[0153] The systems, devices, modules, or units described in the above embodiments can be implemented by a computer or its associated components. The computer may be, for example, a mobile terminal, smartphone, personal computer, laptop computer, in-vehicle human-machine interface device, personal digital assistant, media player, navigation device, game console, tablet computer, wearable device, smart TV, Internet of Things system, smart home, industrial computer, server, or a combination thereof.

[0154] Although not shown, in this embodiment of the invention, a computer-readable storage medium is provided having a computer program / instructions stored thereon, which, when executed by a processor, implements the method for monitoring the state of an integrated linear servo joint as described in the embodiment.

[0155] Storage media in embodiments of the present invention include articles that are permanent and non-permanent, removable and non-removable, capable of storing information by any method or technology. Examples of storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0156] Although not shown, embodiments of the present invention also provide a computer program product, including: a computer program / instructions that, when executed by a processor, implement the method for monitoring the state of an integrated linear servo joint as described in the embodiments.

[0157] The methods, programs, systems, apparatuses, etc., in the embodiments of the present invention can be executed or implemented in one or more networked computers, or practiced in a distributed computing environment. In the embodiments of this specification, in these distributed computing environments, tasks can be performed by remote processing devices connected via a communication network.

Claims

1. A method for monitoring the status of an integrated linear servo joint, characterized in that, Includes the following steps: Step S1: Construct the full-link multibody dynamics topology architecture of the integrated linear servo joint, and establish an integrated dynamics mapping model based on the full-link multibody dynamics topology architecture; Step S2: Extract the degradation characteristics of the spiral interface based on the integrated dynamic mapping model, set the wear depth parameters characterizing different service stages, construct the nonlinear effective deformation function of the contact interface by combining the time-varying asymmetric off-center load distribution model that varies with the nut rotation angle, and obtain the effective contact deformation amount based on the nonlinear effective deformation function. Step S3: Pre-traverse the effective contact deformation amount and the preset friction coefficient range. For each set of effective contact deformation amount and friction coefficient, calculate discrete equivalent contact stiffness scatter data based on the multi-turn thread deformation compatibility equation, and project and encapsulate the discrete equivalent contact stiffness scatter data into a bivariate orthogonal mesh interpolation surface. Step S4: Based on the real-time tangential sliding velocity, determine the instantaneous friction coefficient through a preset friction-velocity mapping relationship; using the effective contact deformation at the current moment and the instantaneous friction coefficient as input, perform interpolation on the bivariate orthogonal mesh interpolation surface to obtain the instantaneous equivalent contact stiffness; within the time step of the implicit integration of dynamics, calculate the contact elastic force according to Hooke's law using the instantaneous equivalent contact stiffness and the effective contact deformation, and feed the contact elastic force back to the system dynamic equation for implicit iterative solution to obtain the instantaneous motion state of the servo joint at the current time step; Step S5: Based on the velocity information in the instantaneous motion state, synthesize the relative sliding velocity in the tangential direction of the conjugate contact surface, and extract the local normal unit vector of the helical contact surface in the integrated linear servo joint; project the contact elastic force along the direction of the local normal unit vector to obtain the total normal contact force vector; Based on the total normal contact force vector and the relative sliding velocity, a regularized friction model is used to generate a friction excitation force vector, and the friction excitation force vector is orthogonally decoupled in three-dimensional space with the normal, circumferential and axial directions as references to obtain the circumferential friction shear force component and the axial friction thrust component respectively. Step S6: The circumferential friction shear force component and the axial friction thrust component are used as external excitations and substituted into the system differential equations corresponding to the integrated dynamic mapping model for numerical solution to obtain the dynamic response of the servo joint; along the helical path of the helical transmission contact interface, the physical quantity time history data of each discrete contact point in the dynamic response are spatially synchronously sampled and reconstructed to generate the spatiotemporal distribution result of the contact interface state. Step S7: Preset monitoring target points on the integrated linear servo joint. Based on the spatial coordinates of the monitoring target points, extract the vibration response signal at the monitoring target points from the spatiotemporal distribution results of the contact interface. Perform high-frequency carrier envelope demodulation analysis on the response signal to obtain the fault characteristic frequency. Construct a multi-source fault evolution mapping map based on the fault characteristic frequency. Obtain the state monitoring results of the integrated linear servo joint based on the multi-source fault evolution mapping map.

2. The method for monitoring the status of an integrated linear servo joint according to claim 1, characterized in that, The full-link multibody dynamics topology includes: a frameless motor, an integrated positioning gear, and a reverse planetary roller screw mechanism with translational and torsional degrees of freedom coordinate systems. The rotor, rotating nut, and positioning gear of the frameless motor of the integrated linear servo joint are configured as a rigid rotating component of the same body. An integrated dynamic mapping model is constructed based on the translational and torsional degrees of freedom coordinate system of the rigid rotating component of the same body and the asymmetric off-center load wear parameters of the time-varying rotation angle of the rotating nut.

3. The method for monitoring the status of an integrated linear servo joint according to claim 2, characterized in that, Obtaining the effective contact deformation includes: Calculate the initial contact deformation ,include: ； In the formula, For any pair of conjugate transmission components Theoretical geometric interference quantity in the normal direction; This is a parameter for the depth of wear and loss. This is the coefficient for asymmetric wear under eccentric loading. For the first The initial circumferential mounting phase of each roller; The angular velocity of the rotating nut; Regarding the initial contact deformation Make a judgment, if If the value is greater than 0, then it represents the effective contact deformation after eliminating wear gaps, indicating that the conjugate components are in a true contact state and can transmit normal elastic force and damping force. When the value is ≤0, it is determined that the contact pair is completely inside the wear gap, and the normal contact elastic force and damping force are forced to zero. At this moment, in the system dynamic equation, it is manifested as the discontinuous disappearance and recovery of the contact force, introducing the alternating impact nonlinear behavior when crossing the gap boundary and transforming it into a time-varying impact excitation source in the system differential equation system.

4. The method for monitoring the status of an integrated linear servo joint according to claim 3, characterized in that, The process of generating the bivariate orthogonal mesh interpolation surface includes the following steps: Based on the damped trust region nonlinear optimization algorithm, the deformation coordination iteration of the thread load distribution of the rotating nut is performed to obtain the equivalent tangential and normal meshing stiffness in discrete scatter form under non-uniform stress state, which is used as discrete equivalent contact stiffness scatter data. Extract the one-dimensional deformation coordinates and one-dimensional friction coefficient coordinates from the discrete equivalent contact stiffness scatter data, generate a two-dimensional orthogonal mesh, and generate a two-dimensional orthogonal mesh manifold based on the two-dimensional orthogonal mesh through tensor product; The stiffness matrix at the orthogonal grid nodes of the two-dimensional orthogonal grid manifold is evaluated by the original scatter interpolator, and the evaluation results are encapsulated to generate a bivariate orthogonal grid interpolation surface based on memory address addressing.

5. The method for monitoring the status of an integrated linear servo joint according to claim 4, characterized in that, The steps for obtaining the circumferential friction shear force component and the axial friction thrust component are as follows: Extract the local normal unit vector of the helical contact surface of the integrated linear servo joint, and obtain the geometric projection coefficient of the helical tangential direction based on the local normal unit vector. When projecting the contact elastic force along the local normal unit vector direction, the contact elastic force is divided by the geometric projection coefficient. Inversely determine the instantaneous normal total contact vector ; Extract the relative sliding velocity in the tangential direction of the conjugate contact surface of the integrated linear servo joint. The relative sliding speed Substituting into the Stribeck model yields the real-time sliding friction coefficient. ; Based on the instantaneous normal total contact force Relative sliding speed and real-time sliding friction coefficient Construct a regularized frictional excitation force vector containing an exponential starting slope and a hyperbolic tangent direction function. : ； In the formula, To enable the gentle slope time constant, This is the velocity tolerance band constant; Using the helix angle, which characterizes the helical morphology, as a spatial transformation operator, the frictional excitation force vector is transformed based on the spatial transformation operator. By orthogonally decoupling the three-dimensional space with the normal, circumferential and axial directions as references, the circumferential friction shear force component and the axial friction thrust component are obtained.

6. The method for monitoring the state of an integrated linear servo joint according to claim 5, characterized in that, Obtaining the spatiotemporal distribution of the state of the contact interface includes the following steps: Using the circumferential friction shear force component and the axial friction thrust component as external excitations, and combining the load-stiffness hardening effect, a system of system differential equations corresponding to the integrated dynamic mapping model is constructed. The system of system differential equations is based on the effective contact deformation. The determination result is used to switch the contact and disengagement states of the elastic force and damping force of each contact pair of the screw drive in each time step, as the dynamic response of the servo joint. An implicit integrator is used to perform adaptive variable step-size numerical solution of the differential equations of the system, and the time history data of physical quantities at each discrete position on the contact interface of the screw drive are obtained. Along the helical path of the helical transmission contact interface, the physical quantity time history data of all discrete contact points are spatially synchronously sampled and reconstructed to generate the spatiotemporal distribution result of the contact interface state; the spatiotemporal distribution result includes a spatiotemporal four-dimensional dataset of contact force, sliding speed and contact state identifier.

7. The method for monitoring the state of an integrated linear servo joint according to claim 6, characterized in that, Obtaining the status monitoring results includes the following steps: A preset monitoring target point is set on the housing or positioning end of the integrated linear servo joint. Based on the spatial coordinates of the monitoring target point, the broadband vibration response signal at the target point location is extracted by interpolation from the spatiotemporal distribution results of the state. Based on the broadband vibration response signal, the high-frequency characteristic frequency of the positioning gear is locked, and the broadband vibration response signal is subjected to envelope demodulation analysis centered on the high-frequency carrier frequency band to extract the low-frequency impact characteristics caused by wear gap impact. Based on the low-frequency impact characteristics, a multi-source fault evolution mapping map based on a single monitoring target is constructed. Based on the characteristic frequency energy changes and trend characteristics in the multi-source fault evolution mapping map, the state monitoring results of the integrated linear servo joint are obtained.

8. A system for monitoring the status of an integrated linear servo joint, characterized in that, The method for monitoring the status of an integrated linear servo joint according to any one of claims 1-7 includes: The preprocessing unit is configured to construct a full-link multibody dynamics topology architecture for an integrated linear servo joint, and to establish an integrated dynamics mapping model based on the full-link multibody dynamics topology architecture. The initialization unit is configured to extract the degradation characteristics of the spiral interface based on the integrated dynamic mapping model, set the wear depth parameters characterizing different service stages, construct the nonlinear effective deformation function of the contact interface by combining the time-varying asymmetric off-center load distribution model that varies with the nut rotation angle, and obtain the effective contact deformation amount based on the nonlinear effective deformation function. The offline unit is configured to pre-traverse the effective contact deformation amount and the preset friction coefficient range, calculate discrete equivalent contact stiffness scatter data based on the multi-turn thread deformation compatibility equation for each set of effective contact deformation amount and friction coefficient, and project and encapsulate the discrete equivalent contact stiffness scatter data into a bivariate orthogonal mesh interpolation surface. The computing unit is configured to determine the instantaneous friction coefficient based on the real-time tangential sliding velocity through a preset friction-velocity mapping relationship; to perform interpolation on the bivariate orthogonal mesh interpolation surface using the effective contact deformation and the instantaneous friction coefficient as input, thereby obtaining the instantaneous equivalent contact stiffness; and to calculate the contact elastic force according to Hooke's law from the instantaneous equivalent contact stiffness and the effective contact deformation within the time step of the implicit integration of dynamics, and to feed the contact elastic force back to the system dynamic equations for implicit iterative solution, thereby obtaining the instantaneous motion state of the servo joint at the current time step. The decoupling unit is configured to synthesize the relative sliding velocity in the tangential direction of the conjugate contact surface based on the velocity information in the instantaneous motion state, extract the local normal unit vector of the helical contact surface in the integrated linear servo joint; project the contact elastic force along the direction of the local normal unit vector to obtain the normal total contact force vector; based on the normal total contact force vector and the relative sliding velocity, generate the friction excitation force vector using a regularized friction model, and perform three-dimensional spatial orthogonal decoupling of the friction excitation force vector with the normal, circumferential and axial directions as references to obtain the circumferential friction shear force component and the axial friction thrust component, respectively. The reconstruction unit takes the circumferential friction shear force component and the axial friction thrust component as external excitations, substitutes them into the system differential equations corresponding to the integrated dynamic mapping model for numerical solution, and obtains the dynamic response of the servo joint; along the helical path of the helical transmission contact interface, it performs spatial synchronous sampling and reconstruction of the physical quantity time history data of each discrete contact point in the dynamic response, and generates the spatiotemporal distribution result of the contact interface state; The output unit is configured to preset monitoring target points on the integrated linear servo joint, extract the vibration response signal at the monitoring target point from the spatiotemporal distribution result of the state of the contact interface according to the spatial coordinates of the monitoring target point; perform high-frequency carrier envelope demodulation analysis on the response signal to obtain the fault characteristic frequency, construct a multi-source fault evolution mapping map based on the fault characteristic frequency, and obtain the state monitoring result of the integrated linear servo joint based on the multi-source fault evolution mapping map.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and, The memory is communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method for monitoring the state of an integrated linear servo joint as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores computer instructions for causing the computer to perform the method for monitoring the state of an integrated linear servo joint as described in any one of claims 1 to 7.

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