53 results about "Nonlinear stiffness" patented technology

A method for rapidly solving transient dynamics of a crack-containing bearing structure of a bogie belongs to the technical field of bogie structure dynamic analysis, and comprises the following steps: acquiring a three-dimensional geometric model of the bearing structure, the geometric dimension of a crack and the position coordinate dimension of the crack; dividing the finite element model of the bearing structure, and carrying out grid division processing on the crack surface; selecting a main degree-of-freedom node of the finite element model on the surface of the bearing structure and the crack surface; performing substructure analysis on the finite element model of the bearing structure; obtaining a mass matrix, a damping matrix and a stiffness matrix of the finite element model of the bearing structure after the degree of freedom is reduced; carrying out constraint simulation on a crack surface node by adopting a one-way nonlinear rigidity unit; processing constraint boundary conditions; processing the excitation load; and solving a dynamic second-order differential equation set, and judging whether the crack surface is in contact or not. According to the method, the opening and closing effects of the crack can be considered, the transient dynamic response of the crack-containing bearing structure under the action of the external load is obtained, and the solving precision and efficiency are both considered.

Anti-vibration units are provided for vibration suppression in multiple directions. The anti-vibration units may have an X-shaped structure as part of its support structure. The anti-vibration units can work for ultra-low frequency vibration isolation in three directions in a passive manner. The anti-vibration units can achieve a flexible nonlinear stiffness, which contains zero or quasi-zero stiffness, negative stiffness and positive stiffness. A smooth multi-equilibria state is also achievable. Compared with traditional spring-mass-damper (SMD) and typical QZS systems, the provided anti-vibration units can have an enhanced QZS range of larger stroke with guaranteed loading capacity, and can also achieve a lower resonant frequency with a lower resonant peak. At least some embodiments of the anti-vibration units may include a new and innovative arrangement of components that enables a more compact design than typical anti-vibration systems.

The invention provides a gap nonlinear control surface flutter wind tunnel test system and method based on steering engine excitation. The system comprises a wind tunnel test section, a test object and a parameter-adjustable excitation mechanism outside a wind tunnel field, wherein the parameter-adjustable excitation mechanism is composed of a transverse clamping mechanism, a longitudinal supporting mechanism, an excitation system and an angle sensor. The excitation system comprises a steering engine, a steering engine rocker arm and a connecting rod, one end of a spring rod is fixed to the longitudinal supporting mechanism, and the other end is in clearance fit with the connecting rod. By adjusting the effective length of the spring rod, the fit clearance and the excitation of the steering engine, the clearance nonlinear rigidity applied to the test control surface can be changed. In a wind tunnel test, an angle sensor is used for collecting rudder shaft rotation angular displacement response in real time, excitation-response characteristic testing before and after flutter occurs is achieved, and the influence rule of gap nonlinear parameters on rudder surface dynamic characteristics is effectively studied. The test principle is simple, and a new way is provided for excitation-response characteristic measurement of the full-motion control surface under different gap nonlinear rigidities.

The invention provides a nonlinear dynamic modeling, solving and control method of a linear motor, and belongs to the field of structural dynamics, and the method comprises the steps: 1) simplifying an LRA into a two-degree-of-freedom mass-spring-damping nonlinear system, and obtaining the linear stiffness and cubic nonlinear stiffness of a beam spring; (2) nBgleff discrete data points of different relative displacements of the motor vibrator and the shell are obtained through simulation, an nBgleff fitting curve is obtained, and then electromagnetic force is obtained; 3) identifying system damping parameters by combining measured data; according to the method, the goodness of fit Rnl of the model to the LRA vibration response is larger than 0.95, vibration characteristics can be accurately predicted, the LRA vibration consistency is effectively improved through the control strategy, and the tactile feedback experience is improved.

The invention discloses a nonlinear acoustic transducer control method and system based on an Aubry-Mather set, and belongs to the technical field of acoustic transducers. The method comprises the following steps: firstly, based on an Aubry-Mather set theory, constructing a nonlinear vibration model used for describing nonlinear vibration of a transducer diaphragm; secondly, based on a nonlinear vibration model, regional piezoelectric driving and dynamic phase regulation are carried out to simulate a quasi-periodic fluctuation mode; then, on the basis of fluctuation characteristics disclosed by the nonlinear vibration model, a multi-diaphragm collaborative vibration system is constructed, and quasi-periodic superposition of sound waves is realized by optimizing diaphragm space layout; and finally, based on stiffness parameters in the nonlinear vibration model, integrating a micro electro mechanical system (MEMS) process and a nonlinear material, and realizing equivalent nonlinear stiffness on a physical device through gradient polarization design. The dynamic adaptability, the energy transfer efficiency and the high-frequency output performance of the transducer in a broadband range are effectively improved, and the transducer is particularly suitable for ultrasonic imaging and other high-frequency acoustic application scenes.

The application discloses a bearing stress state measurement method based on a resonance attenuation method and related devices, and the bearing-main shaft system is loaded in the mode of electromagnetic loading. The resonance attenuation method in the nonlinear parameter identification method is used to obtain an attenuation response curve, and the instantaneous frequency and envelope amplitude are obtained based on a transient time-frequency signal analysis method, and then the main curve is identified from the measured bearing-main shaft system. A quasi-static model of the bearing is established to obtain the mapping relationship between the bearing stress state and the nonlinear non-time-varying stiffness, and the external loading state of the bearing is effectively and accurately detected through multiple tests on the nonlinear stiffness of the bearing system in the actual operation process. The application is suitable for multiple types of assembled angular contact ball bearings and is suitable for accurate measurement of the bearing stress state.

The present application relates to a kind of pipeline vibration absorber with linear-nonlinear characteristics and its design method, wherein, pipeline vibration absorber includes: shell and resonance component;The side surface of shell is the circular arc surface that is attached to the surface of pipeline, and circular arc mounting cavity coaxial with circular arc surface is arranged in shell;Resonance component is installed in circular arc mounting cavity, for presenting linear stiffness or equivalent nonlinear stiffness in vibration state;Resonance component includes: vibrator unit and damping element;Vibrator unit is arranged in circular arc mounting cavity with shell connection, and vibrator unit presents linear stiffness of resonance component with linear characteristics in vibration state based on the connecting structure between shell;Damping element is covered on vibrator unit, and when vibrator unit is in vibration state, damping element is used to present as nonlinear characteristics when physical coupling occurs between vibrator unit and shell, and the equivalent nonlinear stiffness of resonance component is obtained.

The invention relates to the technical field of new energy automobiles, in particular to an electric vehicle suspension key working point displacement checking method and device.According to the method, through parametric modeling and accurate working condition definition, the torque transient response characteristic of an electric vehicle motor is fully considered, and the displacement prediction precision is improved; by adopting a nonlinear rigidity segmented mapping technology, errors caused by linearization hypothesis are avoided, and accurate prediction and one-time qualified design of the suspension performance are realized through displacement check and optimization adjustment; the NVH performance of the electric vehicle is effectively improved, the acceleration of the motor under the Tip-in working condition is greatly reduced, and noise in the vehicle is reduced.

This invention discloses a method and apparatus for designing the stiffness curve of a powertrain mounting system. The design method includes: acquiring vehicle state parameters and stiffness curve data for each mounting; establishing a dynamic model of the powertrain mounting system based on the vehicle state parameters and stiffness curve data, and determining the vibration data for each mounting; comparing the nonlinear stiffness curve data and vibration data of each mounting with preset data conditions, and correcting the stiffness curve data based on the comparison results to obtain a corrected dynamic model; wherein the stiffness curve data includes nonlinear stiffness curve data; and determining the first limit dimension of the mounting based on the comparison results, according to the vehicle state parameters and preset limit rules. The technical solution of this invention, combined with the design of stiffness curve data under actual vehicle conditions, improves the reliability of noise and vibration transmission reduction in mountings, and effectively improves vehicle ride comfort.

The present application belongs to the technical field of nonlinear stiffness identification of vibration excitation device, and particularly relates to a low-frequency vibration table spring piece return mechanism nonlinear stiffness dynamic measurement system and method. The system comprises a program-controlled signal generator, a power amplifier, a low-frequency vibration table installed with a spring piece return mechanism, an eddy current displacement sensor, a data acquisition card, a computer and a software analysis module. The output vibration displacement signals and input standard sinusoidal voltage signals are subjected to FFT analysis by the data processing unit to obtain corresponding signal amplitudes and phases, and then the transfer function of the low-frequency vibration table first-order inertia link form corresponding to the selected amplitude output vibration displacement signals in the working frequency range is calculated by the transfer function calculation unit. Finally, the power series fitting unit is used for power series fitting to obtain the power series expression representing the nonlinear stiffness, thereby completing the dynamic measurement of the low-frequency vibration table spring piece return mechanism nonlinear stiffness. Overall, the measurement system has simple structure, simple measurement method operation process and wide application range, and can realize accurate dynamic measurement of the low-frequency vibration table spring piece return mechanism nonlinear stiffness.

The application relates to a self-resetting torsional energy dissipation support component with nonlinear stiffness, belonging to the technical field of energy dissipation and shock absorption, which comprises an outer sleeve and an inner sleeve which are mutually sleeved, a plurality of torsional steel pipes are arranged in the inner sleeve cavity, rotating discs are fixed at the two ends of the torsional steel pipes, upper and lower core plates which are slidably connected and are used in cooperation with the rotating discs are arranged on the inner sleeve body, support connecting pieces are fixed at the ends of the upper and lower core plates away from the inner sleeve, a plurality of self-resetting spring assemblies are symmetrically arranged in the inner sleeve cavity away from the two ends of the torsional steel pipes, a pair of curve grooves are symmetrically arranged in the center of the rotating discs, struts which are used in cooperation with the curve grooves are arranged on the upper and lower core plates, during work, the upper and lower core plates move towards or away from each other, the rotating discs rotate, the rotating directions of the rotating discs on the two sides of the inner sleeve are opposite during work, the torsional steel pipes are twisted, the metal of the torsional steel pipes is deformed to dissipate energy, meanwhile, the self-resetting spring assemblies are stretched to provide nonlinear restoring force.

The embodiment of the invention provides a foundation pit rigidity analysis method based on performance design and related equipment, and belongs to the technical field of building design. The method comprises the steps that a nonlinear soil pressure displacement function model corresponding to foundation pit supporting is constructed according to the nonlinear relation between supporting structure displacement and soil pressure; deriving the nonlinear soil pressure displacement function model to obtain a nonlinear rigidity model of the foundation soil; the method comprises the following steps: dispersing a foundation pit supporting structure into beam units, and simplifying a surrounding foundation soil body into a distributed spring system coupled with beam unit nodes so as to construct a spring generalized finite element model; and calculating updated soil pressure distribution according to the node displacement and the nonlinear soil pressure displacement function model, and outputting final supporting structure internal force, deformation and soil pressure distribution results. According to the embodiment of the invention, more accurate and more reliable design of the supporting performance of the foundation pit can be realized, and key technical support is provided for safety evaluation of the supporting performance of the foundation pit.

The invention relates to a decoupling device (50) for oscillatory systems, the decoupling device comprising: at least one nonlinear stiffness element having a negative stiffness knl(u) and comprising at least one first spring element (27); and at least one linear stiffness element which has a positive stiffness kl,stat, is connected in parallel with the at least one nonlinear stiffness element, and comprises at least one second spring element (28). The at least one nonlinear stiffness element having a negative stiffness knl(u) is connected in series with at least one further stiffness element having a linear stiffness Kl and comprising at least one third spring element (29), and this series connection is connected in parallel with the at least one linear stiffness element having a positive stiffness kl,stat, wherein a quasi-zero-stiffness isolator is formed with an increased magnitude of the negative stiffness knl,ser,tot(u).

The invention discloses a non-linear rigidity automatic adjusting vibration isolation device and a control method. The device comprises a base, a supporting seat, a positive rigidity mechanism, a negative rigidity mechanism and a dynamic adjusting assembly. The negative stiffness mechanism adopts the design of three layers of uniformly distributed'connecting rod-tension spring 'transmission units, generates negative stiffness by converting vertical displacement of a supporting seat into horizontal movement of a tension spring, and is connected with positive stiffness provided by the positive stiffness mechanism in parallel to form a quasi-zero stiffness core mechanics framework. The dynamic adjusting assembly can accurately adjust the working height of the positive stiffness mechanism, and in combination with a feedback control system with an angle sensor as the core, self-adaptive adjustment of the balance position of the system under different loads and maintenance of the quasi-zero stiffness state are achieved. The positive stiffness mechanism is integrated with a magneto-rheological damper, and the damping force of the magneto-rheological damper can be subjected to real-time and intelligent adjustment through a feedforward-feedback composite control strategy based on multi-sensor information fusion so as to suppress resonance, impact and broadband vibration. The problems that in the prior art, the vibration isolation frequency band is narrow, load self-adaption cannot be achieved, damping adjustment is not intelligent and the like are solved, and high bearing, strong vibration reduction and full-working-condition self-adaption vibration isolation are achieved.

The invention relates to a nonlinear structure reduced-order model construction method based on sparse recognition and a mixed mode, belongs to the technical field of structural dynamics analysis and aeroelastic mechanics analysis, and solves the problem that complex motion caused by geometric nonlinearity under large deformation cannot be accurately described in the prior art. Comprising the following steps: S1, establishing a nonlinear finite element model of a target large flexible wing to obtain a training data set; s2, solving a mixed modal basis based on the displacement residual error and SVD (Singular Value Decomposition); s3, establishing a nonlinear stiffness coefficient solving problem model, introducing LASSO regression to establish an LASSO regression optimization objective function, and solving to obtain a sparse nonlinear stiffness coefficient; s4, based on the sparse nonlinear stiffness coefficient and the structural kinetic equation, establishing a nonlinear structure reduced-order model; and S5, applying the nonlinear structure reduced-order model to statics response solution and dynamics response solution of the large flexible wing to obtain statics response and dynamics response results.

The application discloses a kind of quick solution method for the transient dynamics of bogie containing crack bearing structure, belongs to bogie structure dynamic analysis technical field, it includes: obtaining the three-dimensional geometric model of bearing structure, crack geometric dimension and the position coordinate size of crack;Divide bearing structure finite element model, crack surface is carried out grid division processing;On the surface of bearing structure and crack surface, select the main degree of freedom node of finite element model;Substructure analysis is carried out to bearing structure finite element model;Obtain the mass matrix, damping matrix and stiffness matrix of bearing structure finite element model after reducing degree of freedom;Crack surface node is simulated by using one-way nonlinear stiffness unit and is constrained;Processing constraint boundary condition;Processing excitation load;Solve the second-order differential equation set of dynamics, judge whether crack surface occurs contact or not.The application can consider the opening and closing effect of crack, obtain the transient dynamics response of bearing structure containing crack under external load, and give consideration to solving precision and efficiency.

This invention discloses a method for updating a long-service hydraulic twin model based on multi-fidelity Bayesian methods. It involves collecting non-contact, full-field micro-vibration time-history data of hydraulic structures and extracting high- and low-fidelity data observations. Combining macroscopic physical aging equations, a time-varying degradation prior probability distribution with historical memory is constructed. Based on the high- and low-fidelity data observations, a spatially and mechanistically heterogeneous multi-fidelity twin architecture is built. A spatial covariance matrix of full-field measurement points is introduced, and the Bayesian heterogeneous MCMC method is used to infer parameters of the multi-fidelity twin architecture until convergence. The high-confidence posterior parameters of the structural physical parameters and boundary nonlinear stiffness are mapped to the long-service hydraulic twin model, enabling high-frequency adaptive evolution and synchronous updating of the full life-cycle state of the long-service hydraulic structure digital twin under complex uncertainties.

The invention provides a composite high-order quasi-zero stiffness vibration isolator and an optimization method thereof, and belongs to the field of vibration isolators. The problems that a traditional quasi-zero-stiffness vibration isolator is prone to exceeding a low-stiffness displacement interval under the conditions of low damping and large excitation, dynamic stiffness is sharply increased, resonant frequency drifts and frequency jumps are caused, and the engineering applicability of the quasi-zero-stiffness vibration isolator is seriously limited are solved. A vibration isolation system with a nonlinear rigidity coupling characteristic is constructed by integrating a positive-rigidity supporting spring, a negative-rigidity mechanism and an electromagnetic vibration isolation mechanism. Analysis shows that the high-order quasi-zero stiffness design eliminates the low-order stiffness item through the specific parameter design, expands the quasi-zero stiffness displacement range, and reduces the dynamic stiffness of the system, so that the initial vibration isolation frequency is significantly shifted to a lower frequency, and the formant is well inhibited; the accuracy of the model is verified through numerical simulation and a harmonic balance method, and the advantages of the high-order quasi-zero stiffness system in the aspects of resonance peak suppression and vibration isolation bandwidth widening are proved.

The invention discloses a mechanism and deep learning fused machine tool precision out-of-tolerance fault diagnosis method, and belongs to the technical field of precision numerical control machine tool health management. Comprising the following steps: S10, constructing a tool nose nonlinear dynamic model of a nonlinear stiffness item K (x) considering thermal deformation influence; s20, the inherent frequency, damping and Taylor empirical formula coefficients of the whole machine are obtained in combination with the hammering excitation test and the cutting test; s30, the displacement change of a tool nose is obtained; s40, constructing an out-of-tolerance recognition library; and S50, calculating a precision index of the X (t) obtained under different working conditions, comparing the precision index with a threshold value to generate a qualified / out-of-tolerance label, and carrying out fault prediction based on a 1D-CNN-BiLSTM fusion network training classification model. And finally verifying the precision out-of-tolerance problem of the machining process in combination with field experimental data. The method can solve the problems that the traditional diagnosis technology is difficult to capture in real time, the precision is out-of-tolerance, and generalization is insufficient due to separation of a physical model and a data driving method.

This invention relates to the field of structural dynamics analysis and testing technology, specifically to an aeroelastic analysis method for large flexible structures based on dynamic sparse identification. The method includes: determining the dimensional parameters of the large flexible structure and establishing a finite element model of the large flexible structure based on these parameters; determining the aerodynamic load excitation and applying it to the finite element model of the large flexible structure to obtain the dynamic response; establishing a structural dynamics model to be identified, wherein the basis functions of the structural dynamics model to be identified are determined by multiple different deformation shapes of the large flexible structure; performing sparse identification based on the aerodynamic load, dynamic response, and structural dynamics model to obtain nonlinear stiffness coefficients, thus obtaining the identified structural dynamics model; for the flight condition to be analyzed, iterative processing is performed based on the identified structural dynamics model to obtain the deformation displacement and aerodynamic force distribution of the large flexible structure. This invention can improve the efficiency and accuracy of structural order reduction models.

The invention provides a viscoelastic gap constrained non-linear damping shock absorber which comprises an outer shell provided with a hollow damping cavity. The vibration damper is arranged in the vibration damping cavity; and the multiple adjusting damping fins are arranged in the vibration reduction cavity and used for getting close to or getting away from the vibration damper, and the amount of compression of the adjusting damping fins is changed through backward extrusion of the vibration damper on the adjusting damping fins, so that the nonlinear rigidity parameter and the damping parameter are changed. According to the viscoelastic gap constrained nonlinear damping shock absorber, the problem that an existing linear shock absorber consumes energy in a one-way mode and cannot cope with multi-direction vibration is solved by adjusting the gap between the damping fin and the shock absorber and the backward extrusion effect. The multiple adjusting damping fins surround the vibration damper, extrusion can be formed when vibration comes from any direction, low-amplitude vibration is restrained through slight deformation of the viscous-elastic material when the vibration amplitude is small, the extrusion amount is increased when the amplitude is increased, the energy consumption efficiency is improved, and the vibration damper is suitable for high-amplitude vibration. Nonlinear adaptation of damping characteristics is achieved, and broadband vibration is covered.

This invention relates to the fields of vibration control and nonlinear mechanics, and provides a programmable method for generating two-dimensional nonlinear forces. The method includes: responding to a two-dimensional nonlinear force generation request; acquiring the structure and structural parameters of a mechanical realization device; determining the trajectory of the center point of a rolling component during motion based on mechanical equilibrium relationships, and acquiring the geometric expression of the rolling component's trajectory surface; and, based on the geometric dimensions of the rolling component, performing equidistant mapping along the normal direction on the rolling component's trajectory surface, causing the rolling component to adhere to and roll along a three-dimensional guide surface, thereby generating a nonlinear force corresponding to a target nonlinear force function. This method not only generates nonlinear forces of arbitrary continuous form based on a preset target force function and supports personalized customization of nonlinear stiffness characteristics, but also generates nonlinear forces that meet target requirements in two mutually orthogonal motion directions.

This invention relates to a method for optimizing the target energy transfer characteristics of a nonlinear energy trap system, specifically an elastic plate-piezoelectric nonlinear energy trap system. The method includes: establishing a two-degree-of-freedom model of the elastic plate-piezoelectric nonlinear energy trap system to obtain the dynamic equations of the coupled system; solving for the slow-invariant manifold of the coupled system using the complex variable-average method, and obtaining the parameterized design conditions for the coupled system to exhibit a forced vibration response; solving for the forced vibration response of the coupled system using the harmonic balance method to obtain the system response surface; and optimizing the target energy transfer characteristic threshold range of the system by adjusting the system mass ratio, negative linear stiffness, damping, and nonlinear stiffness within the parameterized design conditions, based on the changes in the system response surface. Compared with existing technologies, this invention provides systematic guidance for the parameter design of the elastic plate-piezoelectric nonlinear energy trap system, improving vibration suppression effects and broadening the target energy transfer characteristic threshold range.

The invention provides an inverted magneto-rheological damper with a nonlinear stiffness characteristic and an adjustable inflation height and an automobile suspension. The inverted magneto-rheological damper comprises an upper connecting spring tray, a lower connecting spring tray, a lower connecting spring tray and an upper connecting spring tray, the upper end of the inner cylinder is connected with the upper connecting spring tray; the piston rod guider is mounted at the lower end of the inner cylinder, and a through hole is formed in the piston rod guider; the floating piston is arranged in the inner cylinder in a sliding mode and divides the inner space of the inner cylinder into a damper energy storage gas cavity and a magnetorheological fluid cavity; the outer cylinder sleeves the outer side wall of the inner cylinder in a sliding and sealing manner, an outer cylinder bottom cover is arranged at the bottom of the outer cylinder, and the outer cylinder and the piston rod guider jointly define an inner and outer cylinder high-pressure air cavity; the lower end of the piston rod is connected with the outer cylinder bottom cover, and the upper end of the piston rod penetrates through the piston rod guider in a sliding and sealing manner and extends into the magnetorheological fluid cavity; the piston ball valve is arranged at the upper end of the piston rod, and the piston ball valve is a one-way piston ball valve; and the lower connecting spring tray is arranged on the outer cylinder.

The present application relates to a kind of electric eddy current damping nonlinear vibration absorber, for hydraulic pipeline, the device includes cable, pulley bearing, metal mass, cable fixing and adjusting device, mounting frame and magnet, cable is threaded in metal mass and is fixed on mounting frame by being encircled over pulley bearing, mounting frame is fixed on hydraulic pipeline, magnet is nested in both ends of mounting frame;When hydraulic pipeline vibrates, metal mass is subjected to the nonlinear restoring force of cable and relative motion is generated with magnet, electric eddy current is generated in metal mass, acts as damping and realizes the suppression of multidirectional vibration in yOz plane.Compared with prior art, the present application has realized the suppression of multidirectional vibration;Nonlinear stiffness is adjusted by cable fixing and adjusting device, with good controllability and adaptability;The movement of metal mass in x direction is limited by mounting frame, and the vibration in plane and out of plane of hydraulic pipeline is reduced, and the like.

This utility model relates to a fine wire stretching machine, providing a small fine wire stretching machine with vibration-resistant offset, including a base plate, a base, a main body, and partitions. The base is fixedly mounted on the base plate, and the main body is fixedly mounted on top of the base. An operating table is slidably mounted on the front of the main body, and multiple partitions are spaced apart within the main body. This utility model effectively blocks the vibration transmission path between workstations by adopting a separate, independent installation structure for the multiple bases of the mold, avoiding the resonance amplification effect caused by traditional integral installation. Simultaneously, an adjustable air spring system is integrated at the bottom of the mold mounting plate. Utilizing its nonlinear stiffness characteristics and adaptive air pressure adjustment function, it not only isolates the high-frequency mechanical vibration generated during equipment operation but also adjusts the support stiffness in real time according to different wire tension requirements, keeping the mold in the optimal working position, thereby significantly improving the stability and processing accuracy of fine wire stretching.

The invention belongs to the field of CARB bearing radial stiffness and elastohydrodynamic lubricating oil film stiffness, and discloses a stiffness calculation method applied to a full-complement CARB bearing of an icebreaker under a low-speed working condition, and the method comprises the steps: building a full-complement CARB bearing stiffness analysis model based on a structure of slice hierarchy-roller hierarchy-bearing hierarchy; and the rigidity of the full complement CARB bearing is solved by combining series coupling and parallel integration. According to the rigidity calculation method, the limitation that a traditional algorithm can only process ideal centering is broken through, the load unbalance loading effect and local oil film rigidity change of the bearing under the non-centering and heavy-load working conditions can be accurately quantified, therefore, the stress concentration risk of the roller edge is effectively recognized, refined modification of the roller convexity is guided, and the precision of the roller convexity is improved. And a nonlinear stiffness parameter conforming to a real physical state is provided for shafting dynamics simulation, and the reliability of bearing life prediction and structural design under a special working condition is remarkably improved.

A multidisciplinary digital twinning modeling method and device for an electric servo mechanism belongs to the field of digital twinning technology and mechatronics systems, and is characterized in that static stiffness analysis is performed on a planetary gear reducing mechanism and a ball screw transmission mechanism to obtain gear pair torsional stiffness and screw pair axial stiffness; then, based on a multi-degree-of-freedom kinetic model and a Lagrange equation, establishing a linearization motion equation including gap nonlinear stiffness; constructing a complete electromechanical control missile multidisciplinary dynamic model; through multidisciplinary coupling modeling, multi-scale analysis and fault model integration, mechanical transmission characteristics, motor and control characteristics and fault mechanisms of the electric servo mechanism can be completely reflected, and corresponding mathematical and simulation models are constructed. The constructed digital twinborn simulation platform can provide solid theoretical basis and technical support for design optimization, performance improvement, fault diagnosis and health assessment of the servo system, and has important application value and popularization significance.

The present application relates to a kind of track type rotary nonlinear energy sink with stiffness damping inertia multi-parameter adjustable, input shaft energy is transmitted to NES disc through connecting rod, then dissipates through damper again.The device is moved on track by input rod driving connecting rod, connecting rod other end compresses spring and damper, to generate nonlinear stiffness and nonlinear damping, ECU controls the angle of track deflection through gear, to realize nonlinear stiffness and nonlinear damping adjustable;ECU controls the position of rack on NES disc, to realize the adjustable of rotational inertia;Sensor is used for real-time monitoring torsional vibration amplitude and angular velocity feedback ECU to carry out parameter adjustment.The present application patent realizes the continuous adjustable of nonlinear stiffness and nonlinear damping by changing rotary track angle, realizes the continuous adjustable of rotational inertia by changing the distance between the centroid of rack and the center of NES disc rotation, simple in manufacture and assembly, low in cost, widen the implementation mode of nonlinear energy sink, with good engineering application value.

The invention relates to the technical field of ocean renewable energy sources, in particular to a wave prediction fused WEC cooperative intelligent control method and system, and the method comprises the following steps: building a kinetic model of a point absorption type adaptive bistable wave energy conversion device based on the Newton second law; the dynamic model comprises self-adaptive bistable nonlinear stiffness force provided by an inclined spring and a horizontal spring; based on a historical wave excitation force sequence, utilizing the trained enhanced depth operator network model to predict a wave excitation force sequence in a future time domain; a kinetic model is used as a prediction model, maximization of energy capture efficiency is used as a target, a predicted wave excitation force sequence and system state constraints are used as conditions, a model prediction control optimization problem is constructed and solved, an optimal power extraction device control force sequence is obtained, a first control quantity is applied to a wave energy conversion device, and a second control quantity is applied to the wave energy conversion device. Rolling optimization is carried out based on the actual state of the system, and cooperative intelligent control over the wave energy conversion device is achieved.