457 results about "Load spectrum" patented technology

The invention discloses a bridge detection method and system based on a digital twin technology, and relates to the field of bridge structure health monitoring. The method comprises the following steps: acquiring a strain distribution value, a vibration spectrum value and an environmental load spectrum value in real time through a sensor network deployed in a physical bridge, generating a structural response data set, and synchronizing the structural response data set to a digital twinborn body; calculating a damage index value and an accumulated damage quantity value based on the structural response data set; inputting the damage index value and the accumulated damage quantity value into a preset safety criterion, and calculating a safety margin coefficient value and a failure risk grade value; calculating a residual life prediction value based on the safety margin coefficient value and the environmental load spectrum value, and synchronously correcting a degradation rate value of the digital twin; and generating a priority maintenance instruction according to the failure risk grade value, the residual life prediction value and the safety margin coefficient value, and feeding back maintenance effect data to the digital twinborn body to complete updating after execution. The bridge operation and maintenance efficiency and safety are remarkably improved.

The invention provides a passenger and goods elevator roof bearing capacity evaluation method with a self-adaptive early warning function, which comprises the following steps of: acquiring data of a multi-source sensor, and performing data acquisition and preprocessing by adopting a dynamic synchronous sampling optimization algorithm; extracting time-frequency characteristics, separating load modes by adopting a multi-dimensional time-frequency analysis algorithm, and constructing a dynamic load spectrum; establishing multi-scale state mapping, calculating system response by adopting a generalized dynamic response analysis method, and evaluating structural risk; and constructing a self-adaptive early warning system, dynamically optimizing an early warning threshold value, and generating an optimal decision scheme. According to the method, the sampling strategy can be adaptively adjusted, the load characteristics can be accurately recognized, multi-scale state evaluation is achieved, early warning decisions are dynamically optimized, and the accuracy and reliability of people and goods elevator top plate bearing capacity evaluation are remarkably improved.

The invention relates to the technical field of material fatigue performance testing, in particular to a fatigue acceleration detection method and system for a high-fatigue-resistance cast wheel, and the method comprises the steps: generating a dynamic load spectrum containing a multi-axis combined load according to the actual operation condition of a target cast wheel; applying a dynamic load spectrum to the target casting wheel to perform an acceleration test, and monitoring dynamic strain responses on the surface and inside of the target casting wheel in real time based on the distributed sensing array; establishing a damage accumulation calculation model by taking a loading parameter of the dynamic load spectrum as an additional correlation condition, and calculating an equivalent fatigue damage accumulation value based on the dynamic strain response; when the equivalent fatigue damage accumulated value reaches a preset damage threshold value, it is judged that the target cast wheel reaches the fatigue life end point, and the damage evolution rule in the acceleration test is kept consistent with the damage mechanism of the actual operation working condition. According to the invention, the problems of multi-axis load simulation distortion, incomplete damage monitoring, low service life prediction precision and the like in traditional fatigue detection are effectively solved.

The invention relates to the technical field of water photovoltaic flexible support pile foundation construction data processing, in particular to a process for a water photovoltaic flexible support pile foundation, which comprises the following steps: fusing meteorological, hydrological and pile deformation multi-source data through a dynamic weight distribution mechanism, and generating a space-time associated dynamic load spectrum by adopting wavelet packet transformation and entropy feature extraction; a collaborative analysis architecture of a finite element simulation and machine learning agent model is constructed, an anchoring depth mapping relation and a real-time design parameter adjustment instruction are output in parallel, and macroscopic fluid parameters and microscopic material degradation characteristics are associated through a data cascade interaction correction mechanism; full-life-cycle data version management is achieved through the block chain technology, and finite element model re-calibration and protection strategy dynamic updating are triggered. The dynamic load response analysis precision and long-term stability of the pile foundation are improved, and the deformation coordination requirement of the flexible support in the complex water area environment is met.

The invention discloses a fatigue load response analysis method for a non-uniform beam of a ship, and particularly relates to the technical field of fatigue load response analys.The vibration coupling degree between the non-uniform beam and other parts of the ship is judged by obtaining the inherent frequency of the non-uniform beam and the other parts of the ship and calculating the vibration coupling degree coefficient; the method comprises the following steps of: acquiring load time-history data of a non-uniform beam, generating a dynamic load spectrum of the non-uniform beam, effectively capturing real load conditions of a ship under various working conditions, and calculating a fatigue damage coefficient of the non-uniform beam through local stress-strain analysis of the non-uniform beam so as to obtain a dynamic load spectrum of the non-uniform beam. A self-adaptive fatigue damage model is constructed based on the vibration coupling degree coefficient and the fatigue damage coefficient, the fatigue damage value of the non-uniform beam is dynamically corrected, the fatigue damage evolution process of the non-uniform beam under different working conditions is reflected through self-adaptive adjustment, and the dynamic property and accuracy of fatigue damage evaluation are improved.

The invention discloses an automobile chassis lightweight structure design method based on topological optimization, and relates to the technical field of lightweight design. Constructing a macro-micro coupling model, and simulating and quantifying material parameter fluctuation by using Monte Carlo; establishing a rigid-flexible coupling multi-body dynamic model, simulating working conditions such as braking and turning, and generating a load spectrum by using a rain flow counting method; constructing a multi-objective function containing light weight, rigidity and modality, and solving manufacturing constraints such as pattern draft and the like by using an NSGA-II (Non-dominated Sorting Genetic Algorithm-II) algorithm; dividing steel, aluminum and carbon fiber material domains; and fusing bench test data to correct the model. According to the method, multi-scale collaborative optimization is realized, dynamic loads are accurately mapped, and light weight and performance are balanced; the connection reliability is improved through the multi-material gradient design; manufacturability is ensured through feature recognition and process verification; the batch consistency is guaranteed by digital twinning and robustness optimization; the chassis design efficiency and quality are integrally improved, and the service life is prolonged.

The invention discloses a cable-stayed bridge tension and compression support service life evaluation method and system under random traffic flow load, and belongs to the field of bridge engineering and structure health monitoring, and the method comprises the steps: carrying out the statistical analysis of traffic load data, building a random traffic flow load model, and generating a load spectrum; correcting stay cable force and modal frequency based on bridge monitoring data, and constructing a refined multi-scale finite element model; a unit fatigue vehicle load is applied to the model, a stress influence line is obtained, a rain flow counting method is adopted to calculate stress amplitude, cycle index and average stress, the stress amplitude, the cycle index and the average stress are converted into daily average equivalent stress amplitude and equivalent daily cycle index through a fatigue damage equivalence principle, and the fatigue life of the tension-compression support is evaluated by utilizing a Miner criterion. According to the method, the problem that the influence of three-way alternating stress on bolt fatigue damage cannot be accurately reflected in the prior art is solved, the service life prediction precision of the cable-stayed bridge tension and compression support is improved, the damage of the tension and compression support can be early warned in advance, and data support is provided for safe operation and maintenance of the cable-stayed bridge.

The present invention relates to a method and apparatus for calculating and evaluating the loss of light collection efficiency of a heliostat. 【Solution means】The present invention simulates the pulsating wind load distribution of a heliostat at different elevation-azimuth angles by CFD calculation, extracts the aerodynamic admittance function and shape parameters, constructs a pulsating wind load spectrum prediction model, calculates the pulsating wind load spectrum by combining the attitude parameters of the heliostat, applies the pulsating wind load spectrum to the structural model of the heliostat mirror by finite element analysis, obtains the instantaneous dynamic response, displacement and strain distribution characteristics of the heliostat, simulates the influence of mirror deformation on the light reflection path, quantifies the instantaneous influence on the light collection efficiency of the deformed mirror, and generates a dynamic curve of the change of light collection efficiency over time.

The invention relates to the technical field of crane equipment health monitoring, in particular to a crane running state health monitoring system and method. A sensing data acquisition unit is used for acquiring a winding drum vibration harmonic component, a steel wire rope leakage magnetic field gradient and a pulley block real-time load; the data analysis unit performs rotating speed synchronous variational mode decomposition on the vibration component to extract resonance characteristics, performs temperature and stress double-compensation correction on a leakage magnetic field gradient, quantifies an energy entropy attenuation rate through wavelet packet decomposition, constructs a phase difference model of a load and vibration to output a slip risk phase offset, calculates a load spectrum damage cumulant, and calculates a load spectrum damage cumulant; and after the four heterogeneous features are fused, a residual life coefficient is output through a dual-channel convolution-long and short-term memory hybrid neural network, and an execution unit triggers crane speed reduction control when the residual life coefficient is lower than a threshold value, so that the problems of insufficient multi-source data fusion and lack of dynamic compensation in the traditional technology are solved, and the fault early warning accuracy is improved.

The invention provides an automatic leak detection method and system for a dynamic bending durability test of a metal corrugated pipe, and relates to the technical field of metal corrugated pipe performance tests.The method comprises the steps that a to-be-tested metal corrugated pipe is installed on a test station, and test working condition parameters are set through a PLC; the test working condition parameters comprise a bending motion mode, a load spectrum, an internal pressure type, a pressure value, a temperature condition and a test frequency; according to the bending motion mode and the load spectrum, a multi-degree-of-freedom bending motion mechanism is driven to apply a dynamic bending load to the metal corrugated pipe; and when the dynamic bending load is applied, internal pressure is applied to the interior of the metal corrugated pipe according to the internal pressure type and the pressure value, and a temperature environment is synchronously applied, so that a multi-factor coupling load is formed. According to the invention, on the basis of working condition setting, through multi-source data acquisition, correction and fusion determination, an automatic closed loop of test execution, abnormity alarm, helium detection quantification and report generation is realized.

The invention relates to the technical field of load spectrum analysis, and discloses a gear random fatigue load processing method and system based on a GCM counting method.The method comprises the steps that actual operation load data and actual operation environment data of a gear transmission system are collected, and torque is converted into instantaneous contact stress; dividing into a plurality of discrete cells based on discretization processing; carrying out clustering analysis on all discrete cells; constructing a two-dimensional gear counting matrix; the asymmetric cyclic stress is converted into equivalent symmetric cyclic stress, and the total service life of the gear is determined; comparing the equivalent symmetric cyclic stress with cyclic stress under a raindrop counting method to determine an adjustment coefficient, and determining an early warning threshold value according to the total service life of the gear and the adjustment coefficient; and comparing the total fatigue damage value with an early warning threshold value to determine an early warning grade. According to the method, joint statistics of the stress amplitude, the average stress and the environmental characteristics is achieved, and the defects of a raindrop counting method in the aspects of processing meshing discontinuous loads and lacking environmental adaptability are overcome.

The invention discloses a cable-stayed bridge cross brace optimization system based on system reliability and an intelligent algorithm, which relates to the technical field of bridge engineering, and comprises a multi-source parameter input module used for collecting and processing data such as a main beam section, stay cable parameters, a strain sequence, a vibration sequence, a satellite cloud picture, a traffic monitoring flow, laser point cloud and the like; and outputting the structured design data, the monitoring data flow, the dynamic load spectrum, the probability distribution model and the construction error correction parameters. According to the invention, all-dimensional data such as design, monitoring, load, materials and construction errors are integrated through the multi-source parameter input module, and multi-level and dynamic reliability evaluation is carried out on the component, the subsystem and the system level by using the system reliability analysis module, so that the component failure probability, the system reliability index time sequence and the like can be output; therefore, the real reliability level of the cross brace of the cable-stayed bridge in the whole life cycle is reflected more accurately, and the one-sidedness of a traditional method is avoided.

The invention discloses a ship shafting reliability evaluation method and system based on multiple working conditions, and the method comprises the steps: collecting multi-source data of a ship propulsion system through integrating multiple sensors; constructing a dynamic load spectrum based on a time-varying Copula function in combination with parameters such as a stress distribution function and a degradation amount distribution function; a reduced basis finite element method is adopted, experimental strain data are collected, and a reduced-order basis matrix is constructed; based on a three-stage Wiener degradation model, in combination with parameters such as a material degradation rate, activation energy and a temperature average value, the residual life of the ship propulsion system is predicted, and model parameters are adjusted in real time through a Bayesian dynamic updating mechanism; building Hamiltonian through physical constraint reinforcement learning, and optimizing operation parameters of the ship propulsion system in combination with a fault probability threshold value and an energy change rate threshold value; a digital twin engine is utilized to provide real-time visual output. According to the invention, the service life is prolonged to the greatest extent while the system meets the performance requirements; and monitoring and decision making by operators are facilitated.

The invention belongs to the field of data processing, particularly relates to a wind turbine generator gear box tooth surface strength optimization method considering multi-working-condition load distribution, and aims to solve the problem that the optimization effect is affected due to the fact that strength optimization checking is carried out only for a single working condition in the prior art. The method comprises the following steps: acquiring working condition data of the gearbox under various preset working conditions; load spectrum decoupling processing is conducted on the working condition data, a dynamic load distribution matrix synchronous with the tooth surface meshing period is determined, stress field conversion is conducted on the dynamic load distribution matrix, and a tooth root bending stress field and a tooth surface contact stress field are obtained; inputting the tooth root bending stress field and the tooth surface contact stress field into a pre-constructed double-constraint optimization model to obtain a tooth surface strengthening parameter tensor output by the model; and inputting the tooth surface strengthening parameter tensor into a preset process mapping system. Based on the method provided by the invention, the multi-working-condition operation data of the gearbox are synchronously obtained for optimization calculation, and the limitation of traditional single load analysis is broken through.

The invention provides an LNG ship pipe fitting fatigue life modeling optimization method and system. The method comprises the steps that a fatigue life simulation model of a low-temperature pipe fitting is established; fatigue state constraint is applied to a fatigue damage structure in the fatigue life simulation model based on the load spectrum and the temperature spectrum at the monitoring node, and a damage constraint condition of the target low-temperature pipe fitting in a vibration state is obtained; determining the thermal fatigue loss of fatigue life simulation under different low-temperature thermal cycle loads according to the thermal fatigue damage and load spectrum characteristics of each connection part under different low-temperature thermal cycle loads; cost optimization is carried out on fatigue life control parameters of the fatigue life simulation model according to the damage constraint conditions and all the thermal fatigue losses, optimal cost parameters for fatigue life simulation under the thermal-vibration load working condition are obtained, and the local grid density of the fatigue life simulation model is adjusted based on the optimal cost parameters. By the adoption of the scheme, parameter cost optimization of the fatigue life simulation model of the LNG ship pipe fitting under the thermal-vibration load working condition can be achieved.

The invention provides an artificial valve leaflet fatigue life evaluation method, system and device and a medium. The method comprises the steps that stress load spectrums borne by artificial valve leaflet surface fatigue failure risk points in a plurality of cardiac cycles are obtained; obtaining the number of load sequence segments of the stressed load spectrum of any cardiac cycle after the trend of the borne load tends to be stable, and the alternating stress, the average stress and the cycle number of each segment of load sequence; calculating the fatigue failure cycle index of the corresponding artificial valve leaflet material standard sample piece under each section of load sequence; calculating the ratio of the cycle number to the fatigue failure cycle number under each section of load sequence to calculate the fatigue damage under the section of load sequence; and obtaining the sum of the fatigue damages under all the load sequences, and obtaining the reciprocal of the fatigue damages as the expected fatigue life. The method has the advantages of being short in time consumption, low in cost, low in difficulty, high in accuracy, high in precision and few in limitation.

The invention discloses a method and a system for testing corrosion fatigue of a bone implantation device under a pathological condition, and relates to the technical field of orthopedic medical device evaluation, and the method comprises the following steps: constructing a dynamic load spectrum database covering physiological and pathological states; in-vitro reproduction of a dynamic mechanical environment borne by the bone implantation instrument in physiological and pathological states is completed through a multi-axis servo system; and acquiring service state data of the bone implantation instrument, and analyzing the service state data of the bone implantation instrument to obtain coupling experiment data. According to the invention, the defects of single load mode and environment simulation distortion in the traditional test method are overcome, high-fidelity simulation and comprehensive monitoring of the corrosion fatigue behavior of the bone implantation device under the pathological condition are realized, the consistency of the in-vitro test result and the in-vivo actual service performance is improved, and the application prospect is wide. And a scientific and unified evaluation basis is provided for material screening, structure optimization and service life evaluation of different types of bone implantation instruments.

The invention belongs to the field of helicopter structure fatigue design, and relates to a helicopter composite material propeller hub damage safety test spectrum compilation method. The method comprises the following steps: selecting a square hole and a flexible arm as a fatigue dangerous part of the composite propeller hub of the helicopter; the square hole is located in the position, close to the rotor shaft, of the flexible arm. The characteristic loads are determined to be the flapping bending moment load of the square hole and the flapping shimmy bending moment load of the flexible arm; in order to monitor the characteristic load of the composite material propeller hub, a strain gauge is attached to the corresponding section, and calibration is carried out; during a damage safety test, loads are applied to all flexible arms of the composite propeller hub of the helicopter at the same time; and according to a damage test result, compiling an actual measurement load spectrum of the helicopter composite material propeller hub.

The invention discloses a hydraulic machine intelligent optimization control method based on big data analysis, and relates to the technical field of hydraulic machine intelligent control, and the method comprises the following steps: carrying out the real-time frequency domain analysis of pressure, flow and energy consumption signals during the operation of a hydraulic machine, constructing a load spectrum analysis module, extracting main frequency fluctuation characteristics, and building a corresponding spectrum template; and performing sliding cross matching on the control threshold change curve of the energy-saving mode switching and the frequency spectrum template, identifying a periodic coupling risk section, and labeling and recording the periodic coupling risk section. According to the invention, through frequency domain analysis and a self-adaptive lag mechanism, frequency resonance type oscillation in energy-saving control is effectively suppressed, and the operation stability and the response reliability of the system are improved; meanwhile, a strategy self-learning mechanism based on resonance labels and energy efficiency feedback is introduced, parameters and control strategies are dynamically optimized and judged, the adaptability and long-term robustness of the system to complex working conditions are enhanced, and intelligentization and high efficiency of energy-saving control of the hydraulic equipment are achieved.

The invention discloses a heavy commercial vehicle chassis virtual load spectrum efficient twin system, and relates to the technical field of automobile chassis. The method specifically comprises the following steps: S1, a load spectrum twinning method based on a virtual iteration method; comprising the following steps: S11, constructing a whole vehicle multi-body dynamic model; s2, an AM-P-sLSTM model is constructed; and S3, a load spectrum twinning method based on the AM-P-eLSTM model is carried out. According to the method, refined construction of the whole vehicle MBD model is achieved, the high-precision rigid-flexible coupling vehicle frame multi-body dynamic model with the flexible body as the main body is established mainly through the vehicle mass center, the rotational inertia and actual measurement data of chassis suspension connecting pieces, and a basis is provided for subsequent virtual iteration and load decomposition; by iterating the road surfaces with different characteristics, the time domain and relative damage error of the iteration signal and the target signal under each road surface are small, the iteration precision is high, and the requirements of subsequent virtual load spectrum twinning and fatigue analysis are met.

The invention discloses a method for rapidly evaluating the service life of a turbine cooling blade based on flight parameters, and belongs to the technical field of aero-engines. The method comprises the following steps: acquiring a load spectrum, a material, a structure and working state parameters of the turbine blade; establishing a blade finite element model and performing fluid thermosetting coupling analysis to obtain temperature field and stress field distribution; determining a dangerous part of the blade based on the temperature field and stress field distribution; respectively establishing a creep durability model, a low-cycle fatigue model and a fretting fatigue life model for dangerous parts; and finally, updating the model based on load spectrum data monitored in real time, and calculating the residual life of the blade. According to the method, the intrinsic performance of the material is associated with the characteristic structure of the blade, and the efficient life prediction model is constructed based on limited test data, so that the life consumption of the turbine blade is quickly and accurately evaluated according to actual flight parameters.

The invention relates to the technical field of turbine blade life analysis, and discloses a single crystal turbine blade simulation piece test parameter design method and system.The critical distance is adopted to correct the dangerous position of a single crystal turbine blade high-low cycle composite fatigue simulation piece, and then resonance analysis of different orders is carried out to obtain the maximum value of the vibration stress of the dangerous position; and finally, analyzing the static stress value of the dangerous position and the maximum value of the vibration stress to obtain a high-low cycle load ratio of the dangerous film hole so as to carry out high-low cycle composite fatigue test load spectrum design of the dangerous film hole and obtain a composite fatigue test load spectrum for carrying out high-low cycle composite fatigue life test analysis on the single crystal turbine blade simulation part. The influence of the static stress gradient on the high-low cycle composite fatigue life is considered, the sensitivity of the stress gradient to the life is reduced, and the problem that the life evaluation error is large due to the fact that the evaluation is conservative by directly adopting a multi-axis fatigue model based on the stress of the stress concentration position is avoided.

The invention discloses a multi-dimensional load spectrum acceleration compilation method for a vehicle frame based on a WLTC working condition, and the method comprises the following steps: setting rigid connection of the vehicle frame, and building a whole vehicle dynamics model; creating a WLTC event working condition, carrying out whole vehicle dynamics simulation, and extracting a load at a connection point; performing finite element analysis by using an inertial release method; carrying out fatigue life analysis on the frame, and extracting fatigue hot spot numbers; reconstructing an analysis process, and extracting stress time sequence data; carrying out pseudo damage analysis on the stress time spectrum to intercept an original load spectrum; carrying out smooth connection processing on the intercepted acceleration spectrum fragments; and performing power spectrum density analysis on the acceleration spectrum and the original spectrum, screening the acceleration spectrum according to a result, and finally obtaining the multi-dimensional load acceleration spectrum of the vehicle frame based on the WLTC working condition, thereby shortening the bench test time and reducing the development cost of the vehicle frame.

The invention relates to the technical field of port cranes and mechanical engineering, in particular to a crane structure fatigue life prediction method and system. The invention provides a crane structure fatigue life prediction method. The crane structure fatigue life prediction method comprises the steps that a finite element model of a crane structure is established, and a stress-load mapping relation matrix of crane structure nodes is generated through dimension reduction processing; collecting actual working data of the crane structure; performing data processing on the actual working data, and constructing an actual working load spectrum; based on the stress-load mapping relation matrix and the actual operation load spectrum, generating a stress-time history used for calculating the fatigue life structure node of the crane; and calculating the fatigue damage of the crane structure and predicting the residual fatigue life by combining a stress-life curve and an accumulative damage theory of a crane structure material. According to the method provided by the invention, online, real-time and accurate prediction and visualization of the fatigue life of all structures of the crane are realized, and a basis is provided for formulating an accurate operation and maintenance plan.

The invention discloses an intelligent variable pitch control method, system and equipment for a wind generating set, and relates to the technical field of wind generating set control, and the method comprises the steps: synchronously collecting multi-source data in real time through a multi-source heterogeneous sensor array, constructing a dynamic load spectrum matrix, and carrying out nonlinear optimization; an optimal pitch angle sequence is generated to drive a variable pitch execution mechanism, meanwhile, the blade stress change rate is monitored in real time, and an aerodynamic load-structure response coupling factor is calculated; when the factor exceeds a safety threshold, the pitch angle command is reconstructed and the pitch angle is forcibly adjusted to a preset safety angle. The technical problems that the power generation efficiency and the structure safety are difficult to consider under the complex turbulence condition and a safety protection mechanism under the over-limit working condition is lacked in the variable pitch control of the existing wind generating set are solved, and the aim that the power generation efficiency and the structure safety are effectively improved through nonlinear optimization control and introduction of an over-limit triggered standby control path is achieved. And the technical effect of dynamic unification of power generation efficiency and structural safety in a complex turbulence environment is achieved.

The invention discloses a bridge anti-fatigue performance analysis and optimization method and system based on finite element analysis. The method comprises the following steps: constructing a bridge finite element basic model and a random fleet time-varying load spectrum, and executing damage-rigidity dynamic coupling iterative calculation; a fatigue sensitive area is automatically identified through the strain energy density gradient, a high-precision sub-model is generated, a basic model stiffness matrix is updated in real time through a sub-model calculation result, and a fatigue evolution cloud picture containing a stiffness degradation track is generated; and finally, identifying a damage hotspot based on the cloud picture, and generating an optimization strategy containing a traffic current limiting threshold and a structure reinforcement opportunity by using a genetic algorithm. According to the method, the problem of prediction deviation of traditional static analysis is solved by simulating the reverse influence of damage on rigidity and internal force redistribution, and accurate evaluation and scientific decision-making of the whole life cycle of the bridge are achieved.

The invention relates to the technical field of data processing, and discloses an aircraft hydraulic pipeline system fault prediction method and system based on digital twinning. The method comprises the steps that flight parameters are acquired through an aircraft data bus for stage identification, and four flight stage identifiers are obtained; carrying out mapping processing on the load spectrum according to the identifier, and constructing a staged digital twin pipeline model; performing weight distribution on the multi-sensor data according to identifiers, and extracting fault feature vectors according to a twin model; and performing prediction processing through the BP neural network in stages to obtain a fault prediction result. The method solves the problem that the existing digital twinborn model cannot adapt to the full flight envelope load difference by adopting fixed parameters, so that the sensor data weight distribution lacks flight stage adaptability, and the fault prediction algorithm cannot accurately identify the differentiated fault features of different flight stages.

The invention discloses a combined harvester chassis frame fatigue life analysis method, and relates to the technical field of harvesters, and the method comprises the following steps: obtaining load data, preprocessing the load data, compiling a load spectrum, building a chassis frame finite element model based on the preprocessed load data, and calculating the fatigue life of the chassis frame. Performing strength check analysis on a front axle, a rear axle and a vehicle body of the chassis frame, analyzing deformation positions and stress distribution of the chassis frame under different working conditions, outputting a stress analysis report, and extracting a strain time history of a dangerous point of the chassis frame based on the stress analysis report and the chassis frame finite element model; and obtaining the stress time history according to the relationship between the stress and the strain. According to the method, through combination of finite element analysis and an actual load spectrum, the fatigue life of each part can be accurately predicted, the possible failure position and the fatigue life can be predicted in advance, and corresponding improvement measures are taken in design and manufacturing stages.

The invention discloses a typical mission profile-based water surface aircraft water surface load spectrum compilation method. The method comprises the following steps of: (1) determining a typical mission profile and a take-off and landing sea area of a water surface aircraft; (2) determining a wave parameter distribution condition of the take-off and landing sea area, and further determining a wave parameter distribution diagram; (3) calculating to obtain a gravity center overload time domain curve of the water surface aircraft under different wave parameters of each mission profile; carrying out filtering and statistical analysis on the gravity center overload time domain curve of the water surface aircraft to obtain a gravity center overload exceeding number of each task profile in each state; (4) weighting according to the proportion time of each working condition of the typical mission profile to obtain a gravity center overload override curve of each stage of the water surface aircraft; and (5) compiling a water surface load spectrum table. Technical reference can be provided for evaluation of the take-off and landing fatigue life of the water surface aircraft.

The invention relates to the technical field of fault diagnosis and bearing life detection, in particular to a high-speed rail axle box bearing life cycle test bench and a test method.The test bench comprises a test bench body, a test head, a driving system, a loading system, a temperature control system, an electrical control system, a computer monitoring system and a data acquisition system; the speed spectrum and the load spectrum can be preset through program control, complex and strong load conditions and variable environment temperatures of a high-speed train can be comprehensively simulated, full-life-cycle tests can be carried out on high-speed rail axle box bearings of various models under high-speed, heavy-load and high-frequency vibration conditions, and the device has the advantages of being easy to operate, safe, reliable and efficient in testing and has a wide application prospect. The problems that in the prior art, the high-speed rail axle box bearing operation environment simulation is incomplete, and the service life evaluation credibility is low can be effectively solved.