94 results about "Random vibration" patented technology

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

The invention relates to the technical field of structural material high-performance calculation and numerical simulation, and discloses a metal rubber random vibration damage and fatigue life prediction heterogeneous parallel method which comprises the following steps: inputting finite element model data of a large-scale metal rubber component; a stiffness matrix, a mass matrix and the like are subjected to accelerated calculation by adopting a CPU multi-thread parallel technology, a frequency response function is calculated by combining a multi-process and multi-thread parallel technology, and random vibration response and component fatigue damage based on a frequency domain method are efficiently calculated by utilizing a GPU parallel computing technology. According to the method, a random vibration theory, a frequency domain fatigue analysis method and a finite element calculation method are combined, and meanwhile, multi-process, multi-thread and GPU heterogeneous parallel calculation frameworks are integrated, so that the calculation efficiency is remarkably improved, efficient analysis of random vibration response and fatigue life prediction of the vibration reduction component made of the complex structural material is realized, and the method is suitable for large-scale popularization and application. And an efficient strategy is provided for design optimization and safe service in the fields of aerospace, high-end equipment and the like.

The invention provides a cold atom gravimeter active vibration isolation method based on slow interference compensation, and relates to the technical field of cold atom gravimeter active vibration isolation, and the method comprises the following steps: building a cold atom gravimeter active vibration isolation model; designing a slow interference compensation law; a Lyapunov stability function is designed; according to the cold atom gravimeter active vibration isolation method based on slow interference compensation, a compensation proportional integral differential control law is designed, and the problem that a current control method cannot adapt to vibration environment change requirements due to the fact that the problem that ground vibration and random vibration caused by the natural environment are not considered is solved. Therefore, the vibration speed and the vibration displacement of the active vibration isolation system of the cold atom gravimeter are rapidly converged, and the control precision of the active vibration isolation system of the cold atom gravimeter is further improved.

The technology is generally directed to determining fatigue damages to an electronic component or a hardware system caused by the transport or movement of the electronic component or hardware system. The electronic components may be, for example, data center hardware components. The electronic components are susceptible to fatigue damage resulting from thermal, shock and vibration events. The thermal, shock, and vibration events may occur, for example, during transport or movement of the electronic components. To fully characterize fatigue, the acceleration and stress cycles may be tracked, which correlate with natural phenomena in the global supply chain and data center environment.

The invention discloses a contact parameter calculation method for improving case random vibration simulation precision based on modal testing. The contact parameter calculation method comprises the following steps: S1, providing a plate part, a frame part and an assembly thereof; s2, performing part modal simulation and part modal testing on the plate part and the frame part respectively to determine material parameters of the plate part and the frame part; and S3, performing assembly body modal simulation and part modal test on the assembly body to determine the contact type and the stiffness parameter of the assembly body, and obtaining contact stiffness parameters under different connection distances in combination with an interpolation algorithm. The method has the beneficial effects that the calculated contact parameters can improve the precision of a simulation model and the accuracy of a random vibration result, and the product reliability is guaranteed while the weight is reduced.

The utility model relates to the technical field of high-voltage distribution box installation, in particular to a high-voltage distribution box installation structure, which comprises an installation foot welded on a high-voltage distribution box, and the installation foot comprises an installation plate used for being fixed with an external vehicle body metal plate. The edges of the two adjacent ends of the mounting plate are bent in the same direction to form a connecting plate and a first welding plate, the connecting plate is connected with the first welding plate, and the end, connected with the first welding plate, of the connecting plate extends outwards to form a second welding plate. The included angle formed between the second welding plate and the first welding plate is equal to the included angle between the two adjacent welding surfaces of the high-voltage distribution box, so that the two stable welding surfaces are formed, and the welding area of the mounting foot and the high-voltage distribution box is increased; and furthermore, the risk that the high-voltage distribution box is separated from the mounting structure and fractured in a random vibration process can be effectively improved.

The application provides a kind of earphone knock detection method, the method comprises the following steps: obtaining the three-axis acceleration data of earphone of current acquisition window, and the change of acceleration is calculated based on three-axis acceleration data to determine dynamic knock threshold;If current instantaneous knock intensity is greater than dynamic knock threshold, it is determined that pre-knock event;If there is second pre-knock of instantaneous knock intensity greater than dynamic knock threshold in the first detection interval for continuous hit waiting after determining pre-knock event, it is determined that continuous hit event and records the number of hits. By calculating the change of acceleration based on the three-axis acceleration data to determine the dynamic knock threshold, the environmental adaptability is improved compared to the setting of fixed threshold, and the response intensity and time of the knock and the continuous hit time after the knock are filtered, effectively filtering short-time random vibration, such as false recognition caused by wearing adjustment or movement, improving user experience.

The invention discloses a new energy automobile battery detection device and method, relates to the technical field of detection equipment, and aims to solve the technical problem of low new energy automobile battery test precision, and the new energy automobile battery detection device comprises a detection device body, a positioning mechanism, a lifting mechanism, a U-shaped seat, a rotating mechanism and a swing mechanism. When the ring pipe and the outer rotating unit rotate simultaneously, the swing mechanism and the elastic telescopic assembly rotate integrally, all collision ball blocks form a stable impact track, uniform, continuous and equal-force impact testing is performed on the surface of the automobile battery positioned below, standard fatigue testing is performed on the automobile battery, and the test accuracy is improved. When the annular pipe and the outer rotating unit are controlled to rotate at a differential speed, the centrifugal force of the collision ball block is changed, so that the collision strength and the collision position on the surface of the automobile battery are changed, random vibration and impact generated during real driving of an automobile are simulated, and the structural fatigue resistance of the automobile battery under the action of long-term complex stress is detected.

The present application relates to the technical field of random vibration test of automobile engine suspension assembly, in particular to a kind of engine suspension random vibration test clamping method, comprising the following steps: data acquisition, preloading, reconstruction coordinates, upper suspension, fixed suspension and upper engine, through the steps of data acquisition and reconstruction coordinates, the reproduction of the suspension suspension position data is realized, so that the installation position of the suspension of different models of engine or motor can be completely reproduced on the frame, the installation height and installation distance, while cooperating with the lifting setting of hydraulic support assembly, to completely and accurately simulate the installation boundary conditions of the suspension on the frame, realize the test clamping installation of suspension, improve the precision and accuracy of suspension test, while avoiding the resource waste of the diversity of suspension clamping fixture.

The invention discloses a method for optimizing the random vibration fatigue life of a laminated welding spot, which comprises the following steps of: establishing a finite element simulation analysis model of the laminated welding spot based on ANSYA software, performing random vibration mode analysis and stress-strain analysis on the model, predicting the fatigue life of the laminated welding spot, determining factors and level values which influence the life of the laminated welding spot, and optimizing the fatigue life of the laminated welding spot. 9 groups of different parameter level combinations are designed by using an orthogonal test method, the vibration fatigue life of the 9 groups of laminated welding spots is predicted, range analysis is carried out, the optimal level combination with the maximum life is obtained, simulation verification is carried out, and the optimization method is simple and obvious in effect, and has certain reference significance for fatigue life optimization of other types of welding spots.

A rocket system level structure vibration simulation and verification method, comprising: constructing a rocket system level structure finite element model based on modal superposition method, carrying out harmonic response analysis, constructing excitation-response transfer function in frequency domain, and determining dynamic load transfer path and amplification effect; combining the power spectral density of the rocket vibration environment, implementing random vibration analysis, quantifying the system level structure strength safety margin by calculating the fatigue life; selecting weak components or typical components to carry out targeted vibration test, and verifying the reliability of the system level vibration simulation method in the above steps through test data. The method can effectively improve the vibration environment prediction accuracy and structure design reliability.

The invention discloses a method for analyzing and optimizing a battery rack structure of a mobile energy storage vehicle through random vibration response. The core of the method is to provide a directional specificity collaborative optimization method for a multi-axis random vibration coupling effect of a battery rack under a complex road condition. According to the method, through modal-random vibration coupling simulation, differential failure mechanisms in all directions are accurately identified and distinguished; a multi-objective optimization model with resonance suppression and stress control as performance objectives and structural weight as cost objectives is constructed, and an optimal balance scheme of performance and light weight is obtained; on the basis, intelligent distribution of the material on a key force transmission path and accurate, efficient and systematic design of the vibration problem of the battery rack are realized, and the safety and reliability of the solid-state battery in a mobile energy storage scene are improved.

The invention belongs to the technical field of aircraft fatigue life design, and particularly relates to an equal stress amplitude vibration fatigue S-N curve determination method and device. The method comprises the following steps: carrying out random vibration response analysis on a structural dynamic finite element model of a cantilever beam with one end clamped and supported, and obtaining a vibration stress power spectral density function and a vibration stress root-mean-square; determining a k-order moment of the vibration stress power spectrum density function; determining a coefficient value of a vibration stress amplitude probability density function formula according to the k-order moment; determining a constant C of the equal stress amplitude vibration fatigue S-N curve; determining a stress amplitude S corresponding to the specified cycle index N according to the constant C; and determining a vibration fatigue SRMS-N curve parallel to the random stress amplitude and a curve passing through the corresponding coordinate points of the cycle index N and the stress amplitude S as an equal stress amplitude vibration fatigue S-N curve. The equal stress amplitude vibration fatigue S-N curve constructed by the invention improves the efficiency of evaluating the vibration fatigue life of the structure.

A high-temperature vibration device includes a large carbon fiber resin-based composite component, a variable diameter support device, an oxyacetylene flame gun, a threaded ejection rod, a support body, a base adapter plate, a laser vibrometer, a support frame, a vibration measuring port, a vent valve, a platinum rhodium thermocouple, and a vibration table. The large carbon fiber resin-based composite component is fixed to the support body for the vibration table, the oxyacetylene flame gun moves and extends to one end of the large carbon fiber resin-based composite component, and the variable diameter support device fixes the oxyacetylene flame gun inside the large carbon fiber resin-based composite component. The flame gun provides a high-temperature ablative thermal environment, the vibration table is fixedly connected to the support body to provide random vibration excitation, and the laser vibrometer passes through the high-temperature vibration box to collect vibration signals.

The utility model discloses a high-vibration-resistance relay driving mechanism which comprises a magnetic pole, an armature which is arranged above the magnetic pole and can rotate, and an elastic element which is used for applying an elastic acting force to the armature in the direction opposite to the magnetic pole, and the armature is provided with a suction end opposite to the magnetic pole. The pull-in end is used for generating magnetic flux with the magnetic pole when the relay is electrified; the armature is further provided with an extending part, the end of the extending part extends to the position opposite to the magnetic pole, and when the armature is in the release state, the distance between the end of the extending part and the magnetic pole is smaller than the distance between the suction end and the magnetic pole. According to the utility model, the extension part is arranged on the armature, so that the electromagnetic attraction to the armature is increased, the elastic force of the elastic element is correspondingly increased, the contact pressure of the relay in a release state is increased, and the random vibration resistance of the product is greatly improved on the premise of not changing the original size of the relay and the ampere-turn of the coil.

The invention belongs to the technical field of data processing, and particularly relates to a battery pack static and random vibration condition simulation result post-processing method, which comprises the following steps of: displaying a result cloud picture according to an input assembly Id number and a part set under the condition-by-condition assembly Id number, setting a legend and a cloud picture maximum value display format in a standardized manner; during the operation of the delay function, the cloud picture is adjusted to the optimal view, the part set cloud picture is intercepted, and the maximum value of the cloud picture is exported into a file for writing a simulation report, so that the time cost is greatly reduced.

The invention discloses an online identification method for nonlinear aerodynamic damping and wind load of a large-span bridge under crosswind excitation. The method comprises the following steps: 1, building a streamline bridge test model; 2, obtaining the vertical displacement of the streamline bridge model under a random vibration test; 3, constructing a nonlinear aerodynamic damping and wind load identification model; and 4, identifying the nonlinear aerodynamic damping and the wind load at each measurement moment by adopting a square root volume Kalman filtering algorithm. The method is simple in step, a nonlinear aerodynamic damping and wind load recognition model is constructed, online recognition of nonlinear aerodynamic damping and wind loads at all measurement moments is achieved through the square root volume Kalman filtering algorithm based on vertical displacement, the method can adapt to random wind load loading, and online joint recognition can be achieved.

According to the X-type large-size metal tube shell mechanical reinforcement and vibration reduction device and the test method, the reinforcement and vibration reduction device reinforces the installation of a device with a fixed size, vibration reduction connection between a to-be-reinforced device and a PCB where the to-be-reinforced device is located is achieved in a subsequent mechanical environment, the problem that the surface of the to-be-reinforced device cracks under vibration can be avoided, and the service life of the to-be-reinforced device is prolonged. The technical bottleneck problems that the random vibration resistance of the parallel seam welding cover plate of the large-size hybrid integrated circuit is improved, so that the reliability of a large-size device is ensured, and the service life of the large-size device is prolonged are solved urgently.

This disclosure provides a thermal, mechanical, and fluid measurement system and testing method for microwave microsystems under complex service environments. The system includes: an environmental simulation subsystem, comprising an internal thermal excitation module and an external environmental simulation module. The internal thermal excitation module generates and outputs target thermal power to simulate the operating heat generation of a power-consuming chip in the microwave microsystem under test. The external environmental simulation module controls the external boundary conditions applied to the microwave microsystem under test, including at least two of thermal conduction boundary conditions, thermal convection boundary conditions, thermal radiation boundary conditions, and random vibrational dynamic loads. A comprehensive measurement subsystem is used to obtain temperature field information, stress-strain information, and liquid cooling fluid parameters of the microwave microsystem under test in the state of coordinated operation of the internal thermal excitation module and the external environmental simulation module. The environmental simulation subsystem and the comprehensive measurement subsystem are integrated in a test platform, and the microwave microsystem under test is placed in the test platform for testing.