最新刊期
期 2 ， 2021
- 摘要：Based on the analysis of the meshing characteristics of non-circular gear and the law of equal engagement angle of tooth profile， considering the influence of relative speed， friction coefficient， oil film thickness， and other key factors on the loss of meshing power， a novel mathematical model for the meshing efficiency of non-circular gear transmission under the elastohydrodynamic lubrication condition is established. By defining a meshing cycle as the period from the tooth top of pitch curve trough to the tooth root of pitch curve crest of non-circular gear， the meshing efficiency of noncircular gear drive is obtained by calculating the power loss of sliding friction and rolling friction under the change of meshing angle.关键词：Non-circular gear;Meshing efficiency;Discretization;Relative velocity
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发布时间：2022-11-10 - 摘要：The meshing temperature of plastic gear affects the mechanical behaviors such as fatigue， wear and noise， which should not be ignored in the mechanical response and performance prediction of plastic gear. In order to predict the meshing temperature of plastic gears， a finite element numerical model of plastic gear temperature field is established considering the temperature-modulus effect of POM material and the multi-heat sources effect of frictional heat and hysteresis heat flux. Based on POM thermo-viscoelastic contact analysis， frictional heat flow and hysteresis loss heat flow are obtained as heat sources. Through the iterative calculation of the interaction between the steady meshing temperature and elastic modulus of plastic gear， the steady meshing temperature and tooth surface flash temperature are obtained. The steady meshing temperature results are in good agreement with the test results， and the flash temperature is in good agreement with the Blok theory. It is found that the temperature rise of hysteresis loss heat has little effect on the steady meshing temperature under dry condition， while the temperature rise caused by friction is the main component of the steady running temperature of plastic gear.关键词：Plastic gear;Hysteresis loss heat;Steady meshing temperature;Flash temperature
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发布时间：2022-11-10 - 摘要：During gait rehabilitation training， patients with hemiplegia or stroke are prone to muscle cramps， which can cause them to lose their balance due to their inability to support their weight and cause secondary injuries. In response to the above problems， a six-degree-of-freedom parallel rehabilitation robot driven by eight cables is designed， which can not only perform gait training on patients but also implement effective anti-fall protection for patients. Firstly， the configuration of the robot is described， and its kinematics model is established by using the closed vector quadrilateral method. Secondly， combined with the characteristics of cable-driven， a concept of a robot force control workspace and its solution method are proposed based on the statics analysis. In order to avoid secondary injuries to patients after losing their balance， a space trajectory safety wall is further proposed based on the force-controlled working space， which classified the possible shapes to be protected for patients and studied the space trajectory path planning method for their return to the safety wall. Finally， two different types of to-be-protected profiles are selected to study the changes in cable length and tension as they moved along the regression trajectory which verified the effectiveness and rationality of the trajectory planning method for the return safety wall.关键词：Cable-driven;Parallel robot;Force control workspace;Space safety wall
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发布时间：2022-11-10 - 摘要：In order to more accurately and quickly solve the shield machine pose change during the tunneling process， a positive solution method for the pose of the shield machine based on the spatial homogeneous transformation matrix element is used to establish a positive solution model of the shield machine pose， and the Newton-Raphson algorithm is used to obtain the nonlinear equations with homogeneous transformation matrix elements as unknown quantities are solved successively， and the numerical solutions of the elements of the homogeneous transformation matrix are obtained. Then， the corresponding poses are solved according to the mapping relationship between the elements of the homogeneous transformation matrix and the poses. According to the constraints of the length of each hydraulic cylinder rod， the mathematical model of the inverse posture solution is established， and the positive and negative solutions of the posture are solved in Matlab. The results show that the error is about 0.018%， within the allowable range of error， which proves the correctness of the mathematical model of the forward and reverse solutions of the shield tunneling position and pose.关键词：Shield machine pose;Posture solution;Pose inverse solution;Homogeneous transformation matrix;Newton-Raphson algorithm
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发布时间：2022-11-10 - 摘要：In order to calculate the contact stiffness of cycloid-pin gear more accurately and guide its practical application， a method for calculating the contact stiffness of cycloid-pin gear based on Monte Carlo was proposed. In this method， the tooth profile functions of cycloid gear before and after the cycloid gear profile modification are established， and the influence of gear profile modification on the contact stiffness of cycloid gear is investigated. Taking RV-40E reducer of industrial robot as an example， the calculation example shows that the contact stiffness of cycloid gear will be changed if the gear tooth profile is modified for cycloid gear， and the contact stiffness of the cycloid-pin gear wheel will first decrease， then increase and then decrease with the increase of the amount of modification.关键词：Cycloid-pin gear;Monte Carlo;Contact stiffness;Gear modification
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发布时间：2022-11-10 - 摘要：In order to study the influence of the rotating pair clearance on the dynamic performance of the main mechanism of gear shaping machine， the non-linear contact impact force model of the clearance with friction and the virtual prototype model of the main mechanism of gear shaping machine with the clearance rotating pair are established. By using the by mechanical dynamics analysis technology，the influence of the impact model parameters，clearance value and clearance number on the dynamic performance of the mechanism are studied. The results show that the root mean square of the slider speed error tends to be stable with the increase of the clearance， and there is a suitable clearance range， so that the root mean square value of the slider speed with multiple clearances is smaller than that with one clearance. The results of the study provide reference for selecting the material of the rotation pair clearance，and controlling the value and quantity of the motion pair clearance.关键词：Gear shaping machine;Transmission mechanism;Rotating pair clearance;Dynamic performance
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发布时间：2022-11-10 - 摘要：In order to select the best contact force calculation method for the dynamics performance analysis of multibody systems involving joints with clearance， a dynamics model of a crank slider mechanism involving joints with clearance is established and a systematic comparative analysis is performed for calculation methods of contact force with the crank slider mechanism involving joints with clearance as the object. The influence of the calculation method of contact force on dynamics performance analysis of the crank slider mechanism under different clearances， crank speeds and recovery factors is studied. The analysis results show that when studying the influences of changes in radial clearance， driving load， and recovery coefficient on dynamics of multibody systems， both the Lankarani-Nikravesh contact force model and the ZhiYing-QiShao contact force model are relatively reliable， and the ZhiYing-QiShao contact force model is the least sensitive to the recovery coefficient.关键词：Clearance;Crank slider mechanism;Contact force model;Multibody systems;Mechanism dynamics
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发布时间：2022-11-10 - 摘要：Laminated couplings are often subject to torque， centrifugal force， axial displacement and angular displacement during operation. The stress analysis of the laminated couplings under various loads can provide a reliable guarantee for the safe operation of the power plant. The finite element model of the six-hole tight-waist laminated coupling considering the contact between the laminated plates is established. The stress value and stress distribution characteristics of the laminated plate under the single effects of torque， centrifugal force， axial displacement and angular displacement are analyzed. And by changing the preload force of the bolts and the friction coefficient between the lamination， their influence on the stress characteristics of the coupling is studied. The results show that increasing the bolt preload and friction coefficient will cause the maximum equivalent stress value of the outermost laminate to increase under the action of torque， axial displacement and angular displacement， but it has little effect on the stress under centrifugal force.关键词：Laminated coupling;Finite element;Stress analysis;Friction
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发布时间：2022-11-10
Theory·Reserach
- 摘要：A new tooth surface design is proposed to spur gears with a tooth surface modification defined by double spline curves， which are used to represent the tooth profile and longitudinal profile， respectively. The tooth surface is obtained by sweeping the tooth profile spline along the longitudinal profile spline. Compared to the traditional comprehensive modification， the tooth surface modification with double spline curves has more control variables， which makes the change of tooth surface geometry more flexible. Moreover， it can achieve the higher order continuity. Through the Finite Element Analysis （FEA）， the advantages of double spline curves modification are analyzed by comparing it with traditional comprehensive modification. The comparison indicates it has superior meshing performances， including the smooth curves of both transmission error and meshing stiffness and decreased frequency amplitudes of static transmission errors. The manufacturing feasibility of the proposed design is also validated by the real machining and measurement. The results show that the proposed new tooth surface modification method is an advanced and practical technology to design high performance spur gear.关键词：Spur gear;Modification;Spline curve;Double spline curve modification;FEA
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发布时间：2022-11-10 - 摘要：Titanium alloy curvature diaphragm is the main diaphragm type of existing flexible diaphragm couplings. Due to its thin thickness， its difficult curved surface processing and requires high precision， a porous linear diaphragm is improved in order to reduce the processing difficulty and ensure the diaphragm has better tolerance and load capacity. The finite element method is used to analyze its axial stiffness， stress and durability under torque， axial deviation， angular misalignment deviation， rotating speed and composite working conditions， and compared it with the single-curvature diaphragm with the same diameter. The research shows that the axial stiffness of the porous linear diaphragm is smaller than that of the single-curvature diaphragm with the same diameter， which also shows nonlinear variation and is proportional to the thickness of the diaphragm. Under axial deviation and angular misalignment deviation， the stress is lower than that of the single-curvature diaphragm， thus having better tolerance capability. Under the same load torque， the stress is larger than that of the single-curvature diaphragm， but it meets the requirements of strength and durability， and the stress distribution of the diaphragm is more uniform. Therefore， the porous linear diaphragm has higher tolerance performance and is suitable for engineering environments with high rotating speed， low load and large axial and angular misalignment deviation.关键词：Diaphragm coupling;Diaphragm surface;Porous linear diaphragm;Strength analysis;Axial stiffness
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发布时间：2022-11-10 - 摘要：Taking the minimizing pose error of the end-effector as the objective function， the inverse kinematics problem of redundant manipulator is transformed into an equivalent optimization problem. An improved particle swarm optimization algorithm is proposed to solve this optimization problem. The algorithm is comprehensively improved from the aspects of particle population initialization， inertia weight adjustment strategy， differential mutation operation as well as the boundary violation treatment of searching space. At the same time， a two-stage hybrid coevolution mechanism based on particle swarm evolution and differential mutation evolution is constructed. As a result， the global exploration and the local exploitation of the algorithm are reasonably and effectively balanced， the convergence precision and speed of the algorithm are improved. Taking the inverse kinematics solutions of a planar redundant manipulator and a 7-DOF redundant manipulator as examples， the proposed algorithm and the comparison algorithms are used to solve the inverse kinematics problem. The simulation results show that compared with the comparison algorithm， the proposed algorithm has higher convergence accuracy， faster convergence speed and stronger optimization stability. The proposed algorithm can effectively solve the inverse kinematics problem of redundant manipulator.关键词：Redundant manipulator;Inverse kinematics;Particle swarm optimization algorithm;Chaos;Mutation
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发布时间：2022-11-10 - 摘要：In view of the present series polishing robot has the problem of insufficient stiffness when grinding spherical， a 3-RSS coaxial drive layout type parallel mechanism tool grinding robot is put forward. The coaxial drive layout is a way of arranging the drives on the same axis. The robot composed of a central base column and three actuated rotating arm that can rotate around this column， each arm is connected by distal linkages to an end polisher. A coaxial driving layout polishing robot model is established through configuration analysis and structural design， and then performs kinematic analysis on the model， the singular position is analyzed through the Jacobian matrix， and a flexible working space for the polisher is obtained. Comparing the preset paths through motion simulation， the motion error analysis with the simulation trajectory verifies the feasibility of the driving scheme. It provides theoretical and technical support for the parallel mechanism grinding robot to expand the working space and improve the stiffness.关键词：Coaxial drive layout;Parallel mechanism;Polishing robot;Kinematics modeling;Simulation analysis
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发布时间：2022-11-10 - 摘要：This study attempts to solve the problems such as low efficiency and relatively small range due to the constraints of device and monotony of vibration in ultrasonic assisted rolling of gears. A novel double-roller longitudinal torsional compound gear ultrasonic rolling system including a longitudinal torsional compound horn and its matching tool gear is proposed. Through the theoretically calculation method， the frequency equation of the horn is derived and the relevant design parameters are calculated. The longitudinal torsional compound vibration displacement and trajectory at the tooth surface are calculated by FEM with spiral grooves in the conical section and the assembled gear. The influences of different parameters of spiral groove such as number， depth， width and helical angle of the groove on torsional longitudinal compound vibration is analyzed by univariate method， FEM and an introduced parameter torsional longitudinal vibration ratio. The optimal parameter combination is obtained and the tool the gear is designed by using lightweight design method. The results show that the design of compound horn meets the requirements， and the effective longitudinal torsional compound vibration of the assembled gear is obtained. The longitudinal torsional compound vibration can be generated with spiral grooves in the conical section. The torsional vibration is mainly related to the number， depth， width and helical angle of the grooves. The double-roller gear longitudinal torsional compound ultrasonic rolling system is obtained by assembling with tool gear， it provides a technical support for the performance of the new gear longitudinal-torsional ultrasonic rolling device.关键词：Ultrasonic rolling;Longitudinal torsional compound horn;Finite element analysis;Gear;Double-roller
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发布时间：2022-11-10 - 摘要：With growing of lower limb exoskeleton robots， large variety of rigid exoskeletons are designed for medical rehabilitation and the other purposes. Compared with the rigid exoskeletons， which added extra inertial to low limb and restricted wearer movement， but the flexible wearable lower extremity exoskeleton minimizes the impact of these factors on the human body locomotion. An exoskeleton that provides assistive force for both hip joint extension and flexion is designed through the variation in hip joint dynamics during strides. Based on the change of hip joint moment， an assistance strategy desired force curve is proposed. In order to obtain the actual force acting on the hip joint， motor is controlled to track the desired force curve PD type iterative learning control （ILC） method is introduced to reduce the error caused by wearing position and biological characteristics to improve assistance performance. In order to evaluate assistance performance， the metabolism of four subjects wearing exoskeleton in the situations of that without assistance， assisting both hip extension and hip flexion， and assisting hip extension respectively is measured. The assistant effect is evaluated through the metabolism. Compared with assisting hip joint extension only and wearing exoskeleton with no assistance， results indicate that the decrease in average net metabolism of assisting both hip joint extension and flexion is 0.445 W/kg and 1.027 W/kg respectively， corresponding to the average net metabolism rate decrease is 7.45% and 15.67%.关键词：Flexible exoskeleton;Hip joint assistance;Force curve;ILC Control;Metabolism
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发布时间：2022-11-10 - 摘要：An automatic drill and riveting robot based on 3-RPC/6-UPS parallel mechanism is proposed to complete the drilling and riveting task of aircraft panel. The robot is equivalent to be a fixed parallel machine tool when performing drilling and riveting， and it also can be seen as a standing robot while walking. The inverse kinematics model of 6-UPS parallel mechanism in charge of controlling the robot drilling and riveting actuator is established. The working space for the end of drilling and riveting actuator is obtained by numerical search method. The inverse kinematics model of 3-RPC parallel mechanism in charge of controlling the robot walking is established. The working space of the upper and lower platform of the 3-RPC parallel mechanism is drawn by numerical search method. The displacement trajectory of the driving rod controlling the robot walking is planned by quintic polynomials， and the smooth walking of the robot prototype is realized in the virtual software. The research work could lay a theoretical foundation for the design of a new type of mobile robot for large-scale structural parts processing.关键词：Parallel mechanism;Aircraft pane;3-RPC;6-UPS;Drilling and riveting
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发布时间：2022-11-10 - 摘要：Taking the planetary gear train of an AT transmission as the research object， the finite element method is used to analyze the dynamic characteristics of the planet carrier， ring gear and housing， and the accuracy of the finite element model of the housing is verified by combining with the modal experiment. The dynamics analysis model of the AT planetary gear system is established and the contact spot experiment is carried out. Through the comparative analysis of the simulation and experimental contact spot results， it is concluded that the meshing spots of the small sun gear-short planet gear and the long planet gear-ring gear pair are basically the same and there is a significant partial load phenomenon. The dynamics model of the AT transmission is obtained by importing the finite element model of the flexible planet carrier， ring gear and housing， and the transmission characteristics of the planet carrier， ring gear and housing flexibility to the planet gears， and the amount of meshing misalignment parameters are analyzed. The results show that the flexible deformation of the casing and the ring gear has the most significant effects on gear misalignment and transmission errors， followed by the planetary carrier flexibility. By improving the support bearing stiffness， bearing preload and gear parameter optimization methods， the planetary gear train gear meshing characteristics are improved， the planetary gear train gear strength and the AT transmission NVH performance are optimized.关键词：AT transmission;Structure flexibility;Planetary gear train;Meshing characteristic
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发布时间：2022-11-10
Design· Calculation
- 摘要：On the basis of the analysis on the circular-arc-tooth-trace cylindrical gear， the geometrical parameters of involute elliptic-arc-tooth-trace cylindrical gear are expounded. It can be concluded that the tooth profiles remain the same involute on any vertical axis section， its tooth thickness is equal to the slot width on the different vertical axis section of the gear teeth， and pressure angle at the reference circle is equal， the expanded tooth trace on reference cylinder is a symmetrical elliptical arc. The equations of tooth surface， transverse tooth profile and contact curve are derived. Meantime， the tilting rotary cutter processing method is proposed. The models of the gear special cutters are established in VERICUT. The elliptic-arc-tooth-trace cylindrical gear machined by the tilting rotary cutter processing method is carried out by VERICUT machining simulation. The contact curve characteristics of the gear pair are analyzed by using the gear models obtained from the simulation. The results show that the elliptic-arc-tooth-trace cylindrical gear pair can achieve full tooth width curve contact， which verifies the feasibility of the machining method. It provides the basis for the machining and application of the involute elliptic-arc-tooth-trace cylindrical gear.关键词：Elliptic-arc-tooth-trace cylindrical gear;Geometric parameter;Tilting rotary cutter;Machining simulation
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发布时间：2022-11-10 - 摘要：In order to improve the analytical result and robustness of modulation signal bispectrum based sideband estimator （MSB-SE）， a method for extracting wear characteristics combining wavelet packet energy （WPE） and MSB-SE is proposed. Firstly， the wavelet packet transform is used to decompose the signal into multiple frequency bands， and the WPE of each frequency band is calculated. The frequency band with higher energy is selected for reconstruction to optimize the analysis frequency band and reduce the calculation amount. Then， the MSB-SE is carried out to extract the characteristics of tooth surface wear， and the online monitoring of tooth surface wear damage state is realized by using a reasonable index. Simulation and experimental results show that the proposed method is more robust， and can more accurately monitor tooth surface wear and evaluate the degree of wear damage.关键词：Gear transmission;Wear monitoring;Modulation signal bispectrum;Wavelet packet transformation
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发布时间：2022-11-10 - 摘要：The 3-DOF spherical gear is proposed and its tooth surface is composed of involute ring tooth surface and semi-spherical bevel tooth surface， the error-free transmission can be realized. Based on the involute forming principle and the coordinate transformation theory， the curved surface equations of annular tooth and arc tooth are derived. According to the meshing principle and motion analysis， the conjugate tooth surface of the arc tooth surface is obtained. The simulation tooth surface and 3D model of 3-DOF spherical gear are obtained by computer， the correctness of tooth surface equation is verified. The basis for the kinematics and dynamics analysis of the 3-dof spherical gear mechanism is provided.关键词：3-DOF;Spherical gear;Tooth surface equation;Meshing principle
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发布时间：2022-11-10 - 摘要：Aiming at the change of frictional power consumption during operation of an aero-engine double-row angular contact ball bearing， based on the rolling bearing dynamics theory， the dynamics differential equations of the double-row angular contact ball bearing are established. The predict－correct GSTIFF （Gear Stiff） integral algorithm with variable step is applied to solve dynamic equations. The influence of bearing operating parameters and structural parameters on its frictional power consumption is analyzed. The bearing structural parameters are optimized by orthogonal test methods. The results show that as the bearing speed， axial load and preload increase， the total friction power consumption of the bearing increases. As the number of rolling elements， the radius coefficients of the inner and outer groove curvatures increase， the total bearing friction power consumption shows a decreasing trend. The radius coefficient of the inner groove curvature has the largest influence on the power consumption of the bearing friction， followed by the number of rolling element， the radius coefficient of the outer groove curvature is the smallest.关键词：Double row angular contact ball bearing;Dynamics;Friction power consumption;Orthogonal optimization
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发布时间：2022-11-10 - 摘要：Considering that spur gears are used under multiple-condition， the modeling method of modified tooth surface for pinion and the multi-condition and multi-objective modification optimization methods of the spur gear transmission are researched. The multi-condition and multi-objective modification optimization design of spur gear transmission under two working conditions is carried out， and the modification optimum design and unmodified tooth surface meshing simulation of a spur gear transmission system are carried out. It is verified by comparison that the spur gear transmission with modification optimization have good comprehensive performance， and its fluctuation amplitude of loaded transmission error as well as maximum flash temperature decrease obviously in both situation. The research results lay a foundation for modification design to improve the comprehensive performance of spur gears.关键词：Spur gear;Modification;Multiple-condition;Flash temperature;Loaded transmission error
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发布时间：2022-11-10
Test·Analysis
- 摘要：Due to the increasing trend of aging society in China， the semi disabled elderly will become a very large group， which will bring great pressure to the elderly care institutions and nursing institutions. Most of the semi disabled elderly suffer from lower limb motor dysfunction and can’t walk independently. Aiming at the group of semi disabled elderly， the structural design scheme of walking assistant wheelchair is put forward， and the mechanical simulation of key components and the kinematic simulation under the condition of man-machine coupling are carried out， and the system framework of walking assistant wheelchair is built. In order to verify the correctness of the theoretical design， the experimental prototype of walking assistant wheelchair is processed， and the relevant experiments are completed. The research results can provide a theoretical foundation for the design of walking assisted wheelchair.关键词：Structural design;Simulation analysis;System framework;Prototype processing;Experiment
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发布时间：2022-11-10 - 摘要：In order to identify the nonlinear classification of bearing fault features more accurately， a fault identification method based on IFOA-SVM is proposed. Firstly， the variational mode decomposition method is used to decompose the vibration signals of the bearing， and the fuzzy approximate entropy and energy entropy of the modal component is used to form fault characteristics. Based on “one versus one” strategy， an OVO-SVM multi-classifier is designed， and the hybrid kernel function combined with polynomial kernel function and radial basis kernel function is constructed. Then， the key parameters such as the ratio coefficient of the kernel function
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发布时间：2022-11-10 - 摘要：Aiming at the problem that the early periodic transient impulse of rolling bearings is not obvious and the spectral kurtosis is poorly analyzed under low signal-to-noise ratio， a method of extracting the weak fault features of rolling bearing based on the combination of multipoint optimal minimum entropy deconvolution adjusted （MOMEDA） and spectral kurtosis is proposed. Firstly， MOMEDA is used as the prefilter to reduce the noise of weak fault impulse signal with strong noise and highlight the periodic impulse component in the signal. Then， through spectral kurtosis analysis， the denoised signal is filtered under the optimal center frequency and bandwidth. Finally， the fault characteristic frequency of bearing signal can be accurately obtained by Hilbert envelope spectrum analysis of filtered signal. The simulation and experimental results show that the method can effectively enhance the periodic transient impulse characteristics of vibration signals and extract the early weak fault characteristics of rolling bearing.关键词：Rolling bearing;Multipoint optimal minimum entropy deconvolution adjusted;Spectral Kurtosis;Weak fault;Feature extraction
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发布时间：2022-11-10 - 摘要：To improve the performance of bearing fault diagnosis， a bearing fault diagnosis method based on Robust Local Mean Decomposition （RLMD） and Kmeans++ is proposed. The product functions （PF） are obtained by decomposing the bearing vibration signal using the RLMD technique. The sensitive PF components are sifted by calculating the correlation coefficients between the PF components and the original vibration signal， and the sensitive PF components are superimposed to form the reconstructed signal. The bearing fault feature set is formed by calculating the time and frequency domain statistical features of the original vibration signal and the reconstructed signal. The Fisher features of bearing failure feature are extracted by linear discriminant analysis （LDA）. The fault feature is clustered by the Kmeans++ clustering method and the cluster center of each bearing working condition is got. The bearing fault identification is realized by calculating the Hamming approach degree between the test sample and the cluster center. The simulated bearing data with different signal-to-noise ratios and bearing data from the Paderborn university test bench are used to evaluate the effectiveness of the proposed method. Results show that the proposed method can accurately identify bearing faults with different categories and levels even though the number of training sample is small.关键词：Bearing;Fault diagnosis;Robust local mean decomposition（RLMD）;Linear discriminant analysis（LDA）;Kmeans++;Hamming approach degree
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发布时间：2022-11-10 - 摘要：The blind deconvolution based on cyclostationarity maximization （CYCBD） is applied to solve the problem that the periodic transient impacts is not obvious at the initial stage of rolling bearing failure under background noise. The noise reduction effect of CYCBD around the filter length and cycle frequency， particle swarm optimization algorithm （PSO） is applied to intelligently optimize CYCBD. Determine the optimal parameters to solve the instability of CYCBD. Firstly， PSO is used to optimize the filter length and cycle frequency in CYCBD to enhance the periodic impacts component. Then， the optimal solution of filter length and cycle frequency is iteratively found by using crest factor of envelope spectrum（EC） as the objective function of PSO. Finally， by applying the optimal solution to CYCBD and conducting envelope demodulation analysis on the enhanced signals， the fault characteristic frequency of bearing signals can be accurately obtained. Through the analysis of simulation signals and experimental data， it is shown that the method can effectively enhance the periodic transient impacts characteristics of vibration signals and has advantages in the early fault feature extraction of rolling bearings.关键词：Rolling bearing;Blind deconvolution based on cyclostationarity maximization;Particle swarm optimization algorithm;Filter length;Cycle frequency
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发布时间：2022-11-10
Development·Application
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