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219 results about "Random vibration" patented technology

In mechanical engineering, random vibration is motion which is non-deterministic, meaning that future behavior cannot be precisely predicted. The randomness is a characteristic of the excitation or input, not the mode shapes or natural frequencies. Some common examples include an automobile riding on a rough road, wave height on the water, or the load induced on an airplane wing during flight. Structural response to random vibration is usually treated using statistical or probabilistic approaches. In mathematical terms, random vibration is characterized as an ergodic and stationary process.

BWBN model-based bridge pier nonlinear earthquake random response analysis method

PendingCN120706186AGeometric CADVirtual/augmented realityAlgorithmEquivalent linearization
The invention provides a bridge pier nonlinear earthquake random response analysis method based on a BWBN model, and belongs to the field of civil engineering structure random vibration analys.The method comprises the steps that discretization processing is conducted on a concrete bridge pier structure, and a finite element nonlinear analysis numerical model is constructed; constructing a BWBN model by combining linear and nonlinear differential equations, setting a hysteresis parameter value of the BWBN model, simulating by adopting an Euler-Bernoulli beam unit, and establishing a degraded beam finite element model; obtaining a unit hysteresis vector, constructing a system motion balance equation, solving an equivalent linearization coefficient, constructing a covariance matrix of random response of the concrete pier structure, performing random response analysis on the concrete pier structure, and exploring typical working conditions of random excitation. According to the method, the operation time is shortened, the calculation precision is improved, and meanwhile, the response characteristics of the reinforced concrete pier structure under nonlinear earthquake random excitation can be truly represented.
Owner:BEIJING JIAOTONG UNIV

Fatigue crack propagation prediction method of cyclic cohesion model of random vibration load

The invention discloses a material fatigue crack propagation prediction method based on a cyclic cohesion model of a random vibration load. The method comprises the following steps: building a crack propagation analysis finite element model based on the cyclic cohesion model; based on the established crack propagation analysis finite element model, calculating the strain of the whole non-cohesion region unit and the separation displacement of the cohesion unit under the current time increment step; according to the separation displacement and the frequency and the amplitude of the current vibration load, the traction force increment in the current time increment step is calculated, and the cohesion strength, the critical separation displacement and the accumulated separation displacement in the traction separation criterion after the fatigue damage increment is loaded are updated; and unit failure judgment is carried out according to the fatigue damage, and if the fatigue damage is reduced to 0 and the cohesive unit rigidity value is reduced to 0, it is judged that macroscopic expansion of fatigue cracks occurs. According to the method, reasonable prediction of fatigue crack growth under the random vibration condition is realized, and the method has wide adaptability.
Owner:DALIAN JIAOTONG UNIVERSITY

Internet of vehicles channel modeling method considering antenna attitude vibration

PendingCN121643957ATransmission monitoringBump steerIn vehicle
The invention discloses an Internet of Vehicles channel modeling method considering antenna attitude vibration, and the method comprises the steps: building an accurate vibration model of an antenna three-dimensional attitude through precisely modeling vehicle body tiny vibration caused by bumping, steering and other factors in vehicle driving into micro-motion of an antenna attitude at three time-varying Euler angles of pitching, rolling and yawing; the time-varying attitude is introduced into a coordinate system rotation matrix, the random vibration characteristic parameterization of the antenna in a three-dimensional space is realized, and then the random vibration characteristic parameterization is coupled to the evolution of key parameters of a channel model, so that the channel rapid fluctuation and beam mismatch effect caused by the antenna attitude jitter can be more accurately reproduced; the method can effectively solve the problems that in the prior art, due to the fact that microcosmic vibration of an antenna is ignored, the fidelity of a model is low, and characterization of a key beam mismatch effect in millimeter wave communication is seriously insufficient, and can provide theoretical basis and data support for performance evaluation and beam management algorithm design of a high-dynamic and high-reliability car networking system.
Owner:CHINA UNIV OF MINING & TECH

Method and apparatus for synthesizing spatially cross-correlated multi-point ground motions fitting response spectrum

Disclosed in the present invention are a method and apparatus for synthesizing spatially cross-correlated multi-point ground motions fitting a response spectrum. The method comprises: using an influence matrix method to obtain ground motion acceleration time histories fitting a target reaction spectrum with high precision, and calculating a Fourier amplitude spectrum and a phase spectrum thereof; and considering a calculation relationship between a power spectral density function and the Fourier amplitude spectrum, taking the power spectral density function of the obtained time histories as an initial value, using a random vibration theory and Cholesky decomposition to obtain spatially cross-correlated multi-point ground motion time histories, further taking into account a phase spectrum of the ground motion time histories fitting the target reaction spectrum with high precision, and performing correction and iteration to obtain spatially cross-correlated multi-point ground motions fitting a response spectrum. The present invention overcomes the shortcomings in current multi-point ground motion time history synthesis techniques, such as the difficulty in ensuring good fitting to a target response spectrum and the non-stationarity of synthesized ground motions, helping to improve the reliability of dynamic response analysis results for large-scale engineering structures under the action of multi-point ground motions.
Owner:JIANGNAN UNIV

Testing tool for random vibration experiment

The utility model provides a test tool for a random vibration experiment, which comprises a support and a vibration elastic sheet, the top of the support is provided with an installation position of the vibration elastic sheet, and the periphery of the installation position is provided with a longitudinal pressing device and a transverse pressing device which correspond to each other; wherein the vibration elastic sheet comprises a short part and a long part, the short part is used for being installed at the installation position, the short part is longitudinally pressed by the longitudinal pressing device in the vertical direction and clamped by the two transverse pressing devices in the horizontal direction, and the long part horizontally extends forwards and is used for installing a sensor for transmitting vibration signals. The problem that in the prior art, in the vibration testing process, a vibration elastic piece is inconvenient to fix is solved.
Owner:SICHUAN CHANGHONG AIR CONDITIONER CO LTD

Acceleration factor calculation method for highly accelerated life test

The invention relates to the field of electrical variable measurement, in particular to an acceleration factor calculation method for a highly accelerated life test, which comprises the following steps: carrying out heating and cooling tests on a PCB (Printed Circuit Board) product, simultaneously carrying out vibration tests on the PCB product, and calculating an acceleration factor of the PCB product for testing the life of the PCB product: H, carrying out cyclic heating and cooling on the PCB product so as to realize rapid temperature change of the PCB product; n, high-frequency random vibration waves are applied to the PCB product, so that the PCB product is in a high-frequency random vibration state; wherein the step H and the step N are carried out synchronously, so that fatigue strength generated by the step H and the step N on the PCB product is coupled to obtain an acceleration factor A; the high-frequency random vibration wave contains energy of more than 2000Hz, so that all components on the PCB product can be vibrated. According to the acceleration factor calculation method for the highly accelerated life test provided by the invention, all failure faults can be easily found in a laboratory, and the test accuracy is improved.
Owner:KUNSHAN HAOSHI INSTR CO LTD

Non-Gaussian random vibration signal generation method and system for controlling kurtosis and peak factor

The invention discloses a non-Gaussian random vibration signal generation method and system for controlling kurtosis and a peak factor. The method comprises the following steps: setting a reference condition for generating a non-Gaussian random vibration signal; a stable non-Gaussian random vibration signal model is constructed, a non-Gaussian random vibration signal is generated through the zero-mean Gaussian random signal and an impact signal, and the impact signal is used for providing a plurality of peaks with different amplitudes for the non-Gaussian random vibration signal; based on a reference condition, through control cooperation iteration of kurtosis and a peak factor, various parameters in the model are solved, and an impact signal is obtained; correcting the power spectral density of the zero-mean Gaussian random signal based on the power spectral density of the impact signal; and synthesizing the zero-mean Gaussian random signal and the impact signal to generate a non-Gaussian random vibration signal. The invention innovatively provides a non-Gaussian random vibration signal generation scheme capable of accurately controlling the kurtosis and the peak factor, and has important practical significance for improving the reliability analysis and test level of an engineering system.
Owner:NANJING UNIV OF SCI & TECH

Stable non-Gaussian random process simulation method

The invention discloses a stationary non-Gaussian random process simulation method, and relates to the field of random vibration numerical simulation, and the method comprises the following steps: obtaining an autocorrelation function through the conversion of a power spectrum density function of a target non-Gaussian random process, and obtaining an autocorrelation coefficient matrix of the target non-Gaussian random process through the autocorrelation function, the autocorrelation function in the step is obtained through Fourier transform calculation. According to the method, FMKL generalized lambda distribution and memory-free nonlinear transformation are combined, non-Gaussian characteristics of natural phenomena such as wind speed and seismic waves are accurately simulated, the defects of a traditional Gaussian model are overcome, and simulation precision and engineering design reliability are improved. By improving the Mehler formula and the spline interpolation method, the equivalent correlation coefficient calculation efficiency is improved, the calculation time is shortened, resource use is optimized, and the method is suitable for large-scale complex engineering structure simulation. The method has flexibility and is widely suitable for various non-Gaussian random process simulation requirements.
Owner:CHONGQING UNIV +1

Dynamic calibration device and method for visual vibration measurement system

The invention discloses a dynamic calibration device and method for a visual vibration measurement system, the device comprises a dynamic standard vibration source, a calibration target, a laser Doppler interferometer, a data processing unit and a control unit, the dynamic standard vibration source outputs steady state, transient state and random vibration signals, the calibration target is fixed at the vibration output end of the dynamic standard vibration source, and the laser Doppler interferometer is fixed at the vibration output end of the dynamic standard vibration source. An acquisition target is provided for a calibration process; the calibrated visual vibration measurement system collects a dynamic image to obtain a vibration measurement parameter, and the laser Doppler interferometer synchronously obtains a standard vibration dynamic parameter; the data processing unit receives the dynamic vibration measurement parameters and the dynamic standard vibration parameters, and quantifies dynamic amplitude deviation, frequency tracking delay and phase difference; and the control unit generates calibration parameters of the calibrated visual vibration measurement system according to the type of the dynamic error under the condition that the dynamic error exceeds an error threshold value. According to the invention, quantitative evaluation and automatic calibration of the dynamic error can be realized, and the calibration precision and efficiency are improved.
Owner:BEIJING CHANGCHENG INST OF METROLOGY & MEASUREMENT AVIATION IND CORP OF CHINA

Method for correcting vibration condition of crawler running at constant speed on land

The invention belongs to the technical field of vibration conditions, and particularly relates to a crawler land constant-speed driving vibration condition correction method, crawler land constant-speed driving vibration data is often regarded as a whole to be processed as a random vibration condition to guide design and examination of parts on a vehicle, and an induction result is usually in a narrow-band + wide-band random form. However, when the crawler runs at a constant speed on the land, the frequency domain characteristic of the vibration data is closer to the form of'sine + broadband random ', and the method is suitable for correction of such vibration conditions. The accuracy of the vibration condition is improved, vibration environment distortion caused by discomfort of the induction method is reduced, and over-test or under-test of the induction vibration test is avoided. According to the invention, the narrowband component in the vibration signal is regarded as the projection of the sinusoidal signal in the power spectral density, the center frequency and the relative amplitude of the narrowband signal are calculated and converted into the frequency and the amplitude of the sinusoidal signal, and the narrowband component is replaced by the sinusoidal component, so that more accurate vibration test conditions are obtained.
Owner:XIAN MODERN CONTROL TECH RES INST

Space large-aperture reflector flexible support design method and support structure

The invention discloses a flexible support design method for a spatial large-aperture reflector and a support structure, and relates to the field of quasi-kinematics support design of large-aperture spatial reflectors. According to the method, a titanium alloy material is selected, parameters such as the size of a connecting frame and the total height of a Bipod support are determined according to the quality of a reflector, the size of a glue spot and an installation space, a cross-shaped blade flexible element is designed to serve as a flexible knot, a three-dimensional parameterized model is established and imported into finite element analysis software, and the three-dimensional parameterized model is obtained. And optimizing structural parameters by taking the RMS value of the optical surface deformation of the reflector as a judgment standard, and finally carrying out dynamic verification such as modal analysis and random vibration analysis. According to the supporting structure, rigidity and flexibility are balanced through a flexible joint, thermal stress can be released, rigidity in the optical axis direction is guaranteed, the bending moment and the influence of machining and assembling errors are reduced, the supporting structure is suitable for reliable supporting of the spatial large-aperture silicon carbide reflector, and the positioning precision and the surface shape precision of the reflector during on-orbit work are effectively guaranteed.
Owner:XIAN INST OF OPTICS & PRECISION MECHANICS CHINESE ACAD OF SCI

Vibration and conventional fatigue load coupled nonlinear damage accumulation prediction method

The invention discloses a vibration and conventional fatigue load coupled nonlinear damage accumulation prediction method. The method comprises the following steps: analyzing and determining a peak stress at a dangerous point under the loading of a conventional fatigue load according to a finite element model of an engineering component; determining a stress amplitude probability density function at the dangerous point under random vibration loading according to structural dynamics analysis; searching a pre-generated material fatigue life curve; determining equivalent stress at the dangerous point under random vibration loading according to the fatigue life curve; calculating the ratio of the peak stress loaded by the conventional fatigue load at the dangerous point to the random vibration equivalent stress, and establishing a coupling damage parameter according to the vibration and conventional fatigue load coupling series; and establishing a nonlinear damage accumulation model of vibration and conventional fatigue load coupling. According to the nonlinear damage accumulation model provided by the invention, the influence of vibration, a conventional load sequence and a coupling series is considered, the parameter determination is simple, and high-precision prediction of structural damage evolution under complex load coupling can be realized.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Security product complete machine test tool

A security product complete machine test tool disclosed by the present invention comprises a bottom plate, a detection frame is fixedly arranged at the top of the bottom plate, and a vibration detection mechanism used for simulating random vibration scenes such as product bumping and crowd shaking on a complete machine is fixedly arranged in the detection frame. Motion detection mechanisms used for simulating complex motion trails are fixedly arranged on the two sides of the outer wall of the detection frame, limiting frames are fixedly arranged on the two sides of the top of the bottom plate, and impact endurance detection mechanisms used for simulating the endurance of products to different impact strengths are slidably arranged in the limiting frames. And an extrusion force detection mechanism for simulating a non-uniform extrusion scene is further arranged in the limiting frame in a sliding manner. According to the device, the multiple detection mechanisms are arranged, so that the defense force of the whole machine can be detected, and meanwhile, the using effects of the whole machine in different environments such as vibration, extrusion and treading environments are simulated.
Owner:DEQING HUOHU TECH CO LTD

Method for optimizing vibration performance of automobile lamp

The invention discloses an optimization method for vibration performance of an automobile lamp. The optimization method comprises the following steps: S101, establishing a finite element model of the lamp and performing modal analysis; and S102, carrying out a modal test by using the lamp. And S103, comparing a modal analysis result in the step S101 with a modal test result in the step S102, confirming a vibration mode and calibrating the finite element model. And S104, submitting modal calculation according to a calibration result, completing boundary condition setting, and performing random vibration simulation. And S105, carrying out a random vibration test on the lamp by using the PSD power spectrum. And S106, comparing a random vibration simulation result in the step S104 with a random vibration test result in the step S105, confirming the reliability of the model and correcting the finite element model. And S107, determining a dangerous area according to a vibration test result and a vibration simulation result, and checking a risk point optimization data structure. And S108, modifying data according to an optimization result, verifying a random vibration simulation result of the new model, and performing vibration test retest after confirming feasibility.
Owner:SAIC VOLKSWAGEN AUTOMOTIVE CO LTD

Failure detection method and device for battery pack bolt, storage medium and program product

The invention discloses a failure detection method and device for a battery pack bolt, a storage medium and a program product, and the method comprises the steps: carrying out the multi-parameter coupling analysis of the axial force and transverse shear component force of a beam unit and a bolt assembly through combining the axial force and transverse shear component force of the beam unit obtained through random vibration simulation; the residual pre-tightening force and the anti-sliding capacity of the bolt assembly are quantitatively evaluated, the failure risk of the bolt assembly is further determined according to the residual pre-tightening force and the anti-sliding capacity of the bolt assembly, the advantages of a frequency domain linear random vibration simulation method are reserved, and the purpose of effectively checking the anti-loosening performance of the bolt can be achieved. The problems that a traditional test is low in efficiency, a simulation model is excessively simplified and failure criteria are incomplete are effectively solved, and the method has the advantages that the detection accuracy is improved, the test cost is reduced, the calculation efficiency is improved, and potential failure points are comprehensively covered.
Owner:CHONGQING TALENT NEW ENERGY CO LTD

Vibration fatigue life prediction method and system based on working condition adaptive spectrum

The invention discloses a vibration fatigue life prediction method and system based on a working condition adaptive spectrum. According to the method, load information of a target structure under various service conditions is obtained, and frequency domain load descriptions corresponding to different working conditions are subjected to weighted fusion according to working condition weights, so that a working condition adaptive load spectrum capable of reflecting real service characteristics is constructed; on the basis, frequency domain stress response of the structure under the random vibration condition is obtained in combination with a structural dynamics analysis model, equivalent stress description of dominant fatigue damage is further determined through a multi-axis equivalent criterion, and fatigue damage distribution is calculated through a frequency domain fatigue analysis method; and finally, predicting the vibration fatigue life of the structure in combination with a material fatigue performance curve and an environment-related performance correction relation. Compared with the prior art, the method has the advantages that the multi-working-condition load superposition effect and the service environment influence can be effectively considered, and the accuracy and engineering applicability of vibration fatigue life prediction are improved.
Owner:HENAN UNIVERSITY OF TECHNOLOGY

Method for evaluating fatigue life of weld joint of hydrogen turbine air inlet shell of engine

The invention discloses a method for evaluating fatigue life of a weld joint of a hydrogen turbine air inlet shell of an engine. The method comprises the following steps: firstly, constructing a finite element model of a turbine air inlet shell welding seam by acquiring three-dimensional characteristics of a welding seam area and combining material parameters; on the basis, a transfer function and a stress power spectral density function of the structure are calculated through modal response analysis and random vibration analysis, a random vibration fatigue life prediction model based on an equivalent SN curve criterion is obtained, and an S-N curve obtained through an experiment and containing average stress is equivalent to an S-N curve under zero average stress; the problem of interference of average stress on random vibration fatigue life analysis is solved, and the experiment cost and time are remarkably reduced. And in combination with a plurality of stress range probability empirical formulas, multi-dimensional accurate prediction of the fatigue life is realized.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS +1

Fatigue damage assessment method under uniformly modulated non-stationary non-Gaussian random load

The invention discloses a fatigue damage assessment method under a uniform modulation non-stationary non-Gaussian random load, which relates to the field of random vibration fatigue damage assessment and comprises the following steps: acquiring a non-stationary random process based on a uniform modulation function; a non-stationary random process obtained by modulating the stationary non-Gaussian random process is defined as a real non-stationary non-Gaussian random process; on the basis of an EPSD decomposition method used for non-stationary Gaussian fatigue damage evaluation, a stationary non-Gaussian fatigue damage evaluation spectrum method is fused to carry out random vibration fatigue damage solving on non-stationary and non-Gaussian stress, the situation of non-stationary and non-Gaussian concurrently in random vibration fatigue damage analysis is further considered, and for the non-Gaussian property, the non-stationary and non-Gaussian random vibration fatigue damage evaluation method is used for solving the random vibration fatigue damage of the non-stationary and non-Gaussian random vibration fatigue damage. More reasonable definition division is carried out on a non-stationary random process, and the problem of random vibration fatigue damage assessment during more complex non-stationary and non-Gaussian concurrently is solved under the condition of a precision reliable spectrum.
Owner:EAST CHINA JIAOTONG UNIVERSITY

Concrete formwork stress monitoring method and system based on intelligent sensor

The invention relates to the technical field of online monitoring, in particular to a concrete formwork stress monitoring method and system based on an intelligent sensor, and the method specifically comprises the steps: collecting environment data of a concrete pouring site, building a concrete environment coupling dynamic model, and outputting a formwork side pressure correction value; collecting working condition data of the template, and importing the working condition data of the template into the random vibration response coupling model to generate a space-time stress threat cloud picture borne by the template in real time; a hydration heat temperature field in the concrete pouring process is monitored in real time, and chemical shrinkage strain generated in the concrete pouring process is obtained; and obtaining a template comprehensive failure index according to the stress threat and the chemical shrinkage strain in the space-time stress threat cloud picture, calculating a time-varying failure probability, and triggering graded early warning through the template comprehensive failure index and the time-varying failure probability. According to the invention, the problem of lagging or misjudgment of failure early warning of the template in the prior art is solved.
Owner:HEBEI ZHONGYUN ENGINEERING MANAGEMENT SERVICES CO LTD

Vehicle-rail-bridge system random vibration analysis method based on interlayer fatigue damage, terminal, medium and program product

The invention discloses a vehicle-rail-bridge system random vibration analysis method based on interlayer fatigue damage, a terminal, a medium and a program product, and the method comprises the steps: constructing random parameter vectors which comprise a vehicle random parameter vector, an interlayer fatigue damage random parameter vector and a rail irregularity random parameter vector; performing random parameter vector point selection based on a multi-distribution point selection method to obtain a random parameter point set; constructing a train-rail-bridge system space random vibration analysis model; and substituting the random parameter point set into the train-track-bridge system space random vibration analysis model for simulation, and solving by combining a numerical integration method and a probability density evolution method to obtain train-track-bridge system vibration response under random interlayer fatigue damage. And meanwhile, multiple random factors such as random fatigue damage of the CA mortar layer and random irregularity of the track are considered, so that the accuracy and reliability of vehicle-track-bridge dynamic response analysis are remarkably improved.
Owner:CENT SOUTH UNIV +3

Electric scooter with holder support and intelligent imaging method thereof

The invention discloses an electric scooter with a holder support and an intelligent imaging method thereof, and the method comprises the steps: synchronously collecting multi-modal motion data through a plurality of sensor groups, and generating a motion characteristic parameter set; an active control intention and a random vibration component are analyzed through a motion separation model, a pan-tilt compensation parameter and a control instruction set are generated, a visual semantic analysis module identifies a scene key target and calculates a motion vector of the scene key target, a pan-tilt view field coverage range is dynamically planned in combination with a reinforcement learning strategy, and a view field optimization parameter is output; a layered control framework is adopted to drive a holder motor to execute target attitude adjustment, and a calibrated control signal is output; based on a control signal and a scene semantic analysis result, a multi-frame fusion algorithm is used for eliminating motion blur and generating a high-resolution image, random vibration interference in dynamic shooting of the scooter is remarkably reduced, the imaging stability is improved, and meanwhile, layered anti-disturbance control and scene sensing imaging are fused, so that the stability of the scooter is improved. The mobility of the scooter is guaranteed, and meanwhile the high-quality shooting effect is achieved.
Owner:SHENZHEN LEQI INTELLIGENT TECH CO LTD

A spring plate for an obstacle detection device

This utility model relates to the field of rail transit technology, and in particular to a spring plate for an obstacle detection device, comprising a horizontal plate, wherein one end of the horizontal plate is bent downward to form a bogie support connection part, and the other end is bent downward to form a crossbeam toothed plate connection part, and the bending areas at both ends of the horizontal plate are arc-shaped; the thickness of the crossbeam toothed plate connection part is less than the thickness of the horizontal plate, and the thickness of the arc-shaped bending area between the two gradually decreases along a first preset direction. While satisfying the original performance, this utility model adopts a gradually changing wall thickness structural design, which enhances the stability of the spring plate under high-frequency, high-amplitude random vibration environments, reduces stress concentration in the bolt hole area, and delays the generation and propagation of fatigue cracks, thereby solving the problem of early fracture of spring plates due to stress accumulation in the prior art.
Owner:SHENGSHI AOTIAN (WUHAN) RAIL TRANSIT EQUIP CO LTD

Life prediction method suitable for high-temperature multi-axis random vibration load

The invention discloses a life prediction method suitable for a high-temperature multi-axis random vibration load, relates to data acquisition, processing and life calculation of a random vibration test, and belongs to the field of fatigue performance of a material under the random vibration load. According to the method, a time domain method and a frequency domain method are combined, and an interaction factor is introduced to correct a von Mises equivalent formula, so that the corrected life prediction model is more accurate in life prediction under a multi-axis working condition; and meanwhile, the normal-temperature S-N curve is corrected, so that the corrected life prediction model is more accurate in life prediction under the high-temperature working condition. And mathematical expressions of the parameters are obtained through a multi-axis random vibration fatigue test. The method provided by the invention has clear physical significance and can be used for predicting the fatigue life of the high-temperature multi-axis random vibration.
Owner:BEIJING UNIV OF TECH

Testing system and testing method for pitching moment of seeker of unmanned aerial vehicle

The invention discloses a test system for pitching moment of a seeker of an unmanned aerial vehicle. The test system comprises a random vibration test platform, a vibration tool, a switching tool, a servo control panel, a data acquisition unit and a data processing unit. The test system constructs a complete monitoring network from vibration input and transmission to servo system dynamic response through a set of targeted acceleration sensor layout and systematic structure integration, thereby realizing accurate quantitative evaluation of the dynamic pitching moment in a vibration environment. A complete monitoring and diagnosis chain for the vibration energy transfer and suppression effect is jointly formed by the collaborative layout of a vibration input point, a transfer path key node, a core moving part supporting structure and a final controlled object. The method has the beneficial effects that how the servo control torque is amplified or suppressed in a vibration system can be accurately traced, and unprecedented and multi-level data support is provided for analyzing the fluctuation source of the pitching torque.
Owner:西安应用光学研究所

Method for predicting damage evolution and performance degradation of bonding interface under action of random load

The invention discloses a method for predicting damage evolution and performance degradation of a bonding interface under the action of a random load, and belongs to the field of bonding interface damage prediction under the action of the random load. The method comprises the following steps: firstly, acquiring a random load signal in a cutting process of a bonding component, carrying out trend term removal processing on the random load signal, and extracting a characteristic section signal; secondly, processing the pre-simulation result of the bonding component to obtain the distribution range of the stress amplitude and frequency of the bonding interface; thirdly, carrying out a vibration load experiment on the standard butt joint bonding sample and the standard shear bonding sample to obtain S-N fatigue life curves in the normal stress direction and the shear stress direction and cohesion parameters after the bonding interface is degraded under different damage degrees; and finally, constructing a bonding component interface damage evolution and performance degradation prediction simulation model, and performing bonding interface damage prediction. The method can effectively predict the damage evolution process and the residual mechanical property of the bonding interface after the action of the high-frequency random vibration load, improves the calculation efficiency, and has guiding significance.
Owner:DALIAN UNIV OF TECH

A method for predicting damage evolution and performance degradation of adhesive interface under random load

The application discloses a method for predicting damage evolution and performance degradation of a bonding interface under random load, and belongs to the field of bonding interface damage prediction under random load. First, random load signals in the cutting process of a bonding component are collected, and the random load signals are subjected to detrending treatment and feature segment signals are extracted. Second, the pre-simulation results of the bonding component are processed to obtain the distribution range of the stress amplitude and frequency of the bonding interface. Third, vibration load experiments are conducted on standard butt bonding samples and standard shear bonding samples to obtain S-N fatigue life curves in the normal stress direction and the shear stress direction, and the cohesive force parameters of the bonding interface after degradation under different damage degrees. Finally, a simulation model for predicting the damage evolution and performance degradation of the bonding interface of the bonding component is constructed to predict the damage of the bonding interface. The application can effectively predict the damage evolution and residual mechanical performance of the bonding interface after high-frequency random vibration load, improve the calculation efficiency, and has guiding significance.
Owner:DALIAN UNIV OF TECH

Accelerated random vibration spectrum determination method based on road load spectrum

The invention relates to the technical field of vehicle assembly vibration fatigue tests, in particular to a road load spectrum-based accelerated random vibration spectrum determination method, which comprises the following steps of: selecting i-circle data of each characteristic road surface under full-load, half-load and no-load working conditions as original data of accelerated random vibration spectrum calculation; calculating an impact response spectrum and a fatigue damage spectrum of the i-circle data of each characteristic pavement; respectively accumulating the fatigue damage spectrum statistical values of the three working conditions; packaging the maximum values of the impact response spectrums under the three working conditions; according to a fatigue damage accumulation theory, calculating a fatigue damage spectrum of the total target mileage according to the number of cycles of three working conditions; packaging the maximum value of the impact response spectrum of the whole circle of characteristic pavement under the three working conditions to obtain the maximum value of the overall target mileage impact response spectrum; synthesizing an accelerated random vibration spectrum by using the fatigue damage spectrum of the total target mileage according to a damage equivalence principle; and finally, carrying out ERS calculation on the generated accelerated random vibration spectrum, and checking the correctness and rationality of the accelerated random vibration spectrum.
Owner:SHAANXI HEAVY DUTY AUTOMOBILE CO LTD

Sensitive wavelength identification method, device and equipment for riding comfort of high-speed railway

The invention provides a high-speed railway riding comfort sensitive wavelength identification method, device and equipment. The method comprises the following steps: establishing a dynamic model of a train-rail-bridge space coupling random vibration system; the dynamic response of the train-track-bridge space coupling random vibration system under track irregularity random excitation is solved, and a train body vibration response power spectrum is obtained; dividing the random track irregularity spectrum into a plurality of wavelength components according to upper and lower cut-off wavelengths of different wavelengths; on the basis of the vehicle body vibration response power spectrum, comfort indexes corresponding to all wavelength components are calculated, sensitive wavelengths of full wave bands are recognized, and the riding comfort and the sensitive wavelengths are recognized. The high-speed railway riding comfort sensitive wavelength identification method effectively overcomes the defects of low calculation efficiency and insufficient identification capability in the prior art, and provides a high-speed railway riding comfort sensitive wavelength identification solution with high efficiency, accuracy, mechanism definition and strong engineering practicability.
Owner:HUNAN UNIV OF SCI & TECH

Method for simulating force condition of vehicle-mounted controller and storage medium

The present application relates to the stress simulation method and storage medium of vehicle-mounted controller, first build vehicle-mounted controller simulation model, use finite element simulation analysis to carry out modal analysis, random vibration, impact load strength analysis and check to the equipment structure, determine whether resonance occurs; Whether the load working condition meets the checking standard; Can ensure that the given structure, material and other properties meet the safety factor; If the safety factor is not met, the structure, material and other properties of the vehicle-mounted controller need to be improved and adjusted, and correct guidance is given to the design to avoid deformation, rupture and other risks caused by unreasonable design, leading to vehicle accidents, and protecting the safety of life and property.
Owner:QINGYUAN MAGLEV TRANSPORTATION CO LTD

A method and system for calculating energy-averaged finite element method for structural random vibration analysis

This invention belongs to the field of structural vibration analysis technology and discloses an energy-averaged finite element method and system for structural random vibration analysis, including: S1, using fluid simulation software Fluent and StarCCM to perform fluid dynamics simulation to obtain the long-term turbulent pulsating pressure distribution of the structural wall in the time domain; S2, dividing the pulsating pressure obtained in S1 into segments with some overlap between segments, and performing Fourier transforms on each segment to obtain multiple sets of wall turbulent pulsating pressures in the frequency domain; S3, establishing a fluid-structure interaction dynamic model of the structure and fluid domain, applying the wall turbulent pulsating pressure loads obtained in S2 in the frequency domain, and performing steady-state dynamic harmonic response analysis on each segment; S4, based on the vibration response results of the multiple sets of harmonic response analyses in S3, taking the energy average of these results to obtain the result of random vibration analysis.
Owner:HUAZHONG UNIV OF SCI & TECH