最新刊期
期 2 ， 2018
- 摘要：Based on the material thermodynamics and heat treatment commercial simulation software,and taking the actual heat treatment process of the half axle gear of the automobile into account,the effect of deep cryogenic treatment on the deformation of the half axle gear is explored. Taking the 20CrMnTi half axle gear as the research object,by using the DEFORM software,the process of gear carburizing-quenching and deep cryogenic treatment is simulated,by using the JMATPRO software,the material performance database of 20CrMnTi half axle gear is established. The gear deformation information after gear carburizing-quenching and deep cryogenic treatment is obtained. The simulation results show that there is deformation after carburizing-quenching and the radial deformation affects the performance,that is,after the deep cryogenic treatment,the deformation range is reduced,while the radial deformation does not change.关键词：DEFORM;20CrMnTi;Half axle gear;Carburizing-quenching;Deep cryogenic treatment;Deformation
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发布时间：2022-10-20 - 摘要：Comprehensive optimization of fuel economy and emissions of diesel engine hybrid plug-in electric vehicle has been investigated. A vehicle dynamic model considering Selective Catalytic Reduction（ SCR） aftertreatment system is established on MATLAB/Simulink simulation platform. A multi-objective optimization function with fuel consumption and SCR outlet’s NOxemission is developed by adopting two states dynamic programming algorithm to solve global optimization problem. Specifically,the battery SOC and SCR temperature is designated as two states respectively which reflect the powertrain system and aftertreatment system dynamics. Based on the optimized results,a rule-based control strategy which is applicable for real-time control is deduced. Compared with CS-CD control strategy,the simulation result shows the fuel economy and NOx emission both is decreased by 1. 9% and 9. 3%.关键词：Diesel engine hybrid plug-in electric vehicle;Exhaust aftertreatment;SCR;Dynamic programming
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发布时间：2022-10-20 - 摘要：On the basis of processing principles of torus-involute gear,the longitudinal modification method based on continuous shifting is used for the pinion in the face gear drive,a modified face gear pair is obtained. At first,based on the differential geometry theory and the space mesh theory,the tooth surface equations of the modified face gear pair are derived. Then,the tooth contact analysis（ TCA） and curvature interference inspection are conducted. The numerical example shows that the proposed novel modified face gear pair has following features of can avoid the occurrence of gear deviation load and can decrease the sensitivity of the contact path to the installation errors,there is no curvature interference at meshing points. At last,based on the finite element method,the loaded tooth contact analysis（ LTCA） is conducted by ABAQUS.关键词：Continuous shifting;Longitudinal modification;Face gear;TCA;Curvature interference inspection;LTCA
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发布时间：2022-10-20 - 摘要：In order to reveal the nonlinear dynamics behavior of the transmission mechanism of the roller movable tooth. A translational-pure torsional coupled dynamics model is established with considering the number of movable tooth,the gap between the teeth and the dynamic loads. The relative displacement between the various parts of the meshing line is derived. The system nonlinear dynamics differential equations and coordinate transformation of differential equations are worked,and the non-dimensional treatment is carried out. The dimensionless differential equations is solved by the numerical analysis software,the phase diagram and Poincare diagram are obtained. The influence of parameter variation on the nonlinear characteristics of the system is analyzed by change the parameter of eccentric distance and meshing damping. The results show that the movement of system is different by the changing of the eccentric distance. With the reducing of the eccentric distance,the system enters the periodic movement through the chaotic motion,and then enters the chaotic motion through the quasi-periodic. If the eccentric distance is not choose bigger and smaller,the vibration response amplitude of the mechanism is reduced,the stability of the system can be improved.关键词：Roller movable tooth;Nonlinear;Phase diagram;Poincare
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发布时间：2022-10-20 - 摘要：Use the space meshing theory to study the meshing theory of end-face worm drive,all of the worms systematically are discussed,the unified formula for the worm wheel tooth surfaces is presented. The unified formulas of the end-face worm drive meshing performance are deduced. Though an example,the meshing performance of end-face worm drive is analyzed. Thus a foundation is laid for the research and manufacture of end-face worm drive and the development of CAD system.关键词：End-face worm drive;Meshing theory;Unified formula;Contact line
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发布时间：2022-10-20 - 摘要：Both theoretical analysis and practical application prove the existence of the deflection of the flexspline teeth. The change of meshing trajectory and backlash of circularspline and flexspline on the different section shows that the tooth deflection makes the axial part of flexspline teeth near the bottom of the tube easy to engage at the front part of meshing time,then meshing is easy to appear on the axial part of flexspline teeth near the mouth of the tube. The most meshing of the section on the conjugate meshing area is interfered. The meshing interference caused by tooth deflection occurs earlier in the non working side of the tooth. The meshing interference makes the force of the flexspline increase,and produces periodic bending deformation of the flexspline,which may make fatigue crack. The different wave generators have a certain influence on backlash fluctuations,but not very seriously.
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发布时间：2022-10-20 - 摘要：A research of applying EHL stress to gear contact strength design. The design formulas of gear contact strength are given based on the EHL stress fitting formulas. The influence of various influencing factors such as load,speed,and lubricating oil viscosity on design result is investigated,and the design results respectively based on EHL stress and Hertz stress are compared. The results indicate that like Hertz stress,EHL stress can be also taken as the design basis for contact strength design,and the design result based on EHL center stress fitting formula is very close to that based on Hertz stress formula,but in case of high speed,because EHL spike stress is much bigger than EHL center stress,the EHL spike stress should be considered as the design consideration of gear contact strength.关键词：EHL stress;Hertz stress;Gear strength design
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发布时间：2022-10-20 - 摘要：The results of Assur group model synthesis and number synthesis are briefly discussed,a combination of kinematic chain characteristic value is used to marker the result of number synthesis. Based on the analysis of kinematic chain characteristic value expression,the data rang of mutiple components or multiple joints,binary component and the key points and so on are analyzed and discussed. On the basis of above analysis,the number synthesis method of planar kinematic chain is proposed based on the dichotomy. With high computing efficiency,all the number synthesis results for 4 10 components with multiple joints are obtained,and then some samples are listed to analyze the effectiveness of the number synthesis results. The necessary information for the digital kinematic chain type integrated is provided by the above results.关键词：Kinematic chain;Number synthesis;Eigenvalue;Multiple complex hinge;Dichotomy
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发布时间：2022-10-20 - 摘要：The moving mechanism configuration has a major impact on the static stability,dynamic stability and driving force of the wheeled service robot. Taking the six-wheel mobile underpan as the object,the relationships between the wheel layout and the static stability,dynamic stability,driving force to cross obstacle and turn are analyzed. A multi-objective optimization model for wheel layout is established and the optimal solution is derived by using MATLAB genetic algorithm toolbox. Assuming the factors of pitch angle,roll angle and drive torque as evaluation indicators,motion simulation of the mobile underpan is carried out by the virtual prototyping technology. The results show that the pitch angle and roll angle after optimization are decreased by17. 6% and 27. 2%,respectively. The average value and mean square of drive torque are decreased by 2. 8%and 3. 6%,respectively. It is beneficial to the transmission performance and endurance of the mobile underpan. The results also verify the correctness and validity of the established multi-objective optimization model.关键词：Moving mechanism configuration;Wheel layout;Multi-objective optimization;Virtual prototype simulation
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发布时间：2022-10-20 - 摘要：The study object is the new controllable machinery loader,the design variable is the key parameters of boom lift branched,and the optimization goal is the least of maximum torque of the first during active-member lifting,and the constraints are overall layout,transmission angle and singularity,then the dimension optimization model of boom lift branched is built. What’s more,by using complex method,the numerical solving on optimization model is carried out and the best dimension parameters of each member of boom lift branched are obtained and the maximum drive torque of first active-member is lowered by 11%. Finally,the virtual prototype simulation based on ADAMS is conducted. The simulation result shows that the dynamics performance of optimized controllable loading mechanism is significantly improved. When boom is at the top position the first active-member is close to the inverse kinematics singular position and the power is reduced by80%. This study will provide a basis for performance promoting of controllable machinery loader.关键词：Controllable loading mechanism;Upper lifting condition;Dimensional optimization;Complex method
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发布时间：2022-10-20 - 摘要：Based on the motion characters of the running cars,a foldable 2 RUS/2 RRS parallel mechanism is proposed as a car motion simulation platform. The geometrical relationship of force screw supplied by the branches is obtained,and the degrees of freedom feature is gotten. Also,based on the Grassmenn geometry,the input selection rationality of the mechanism is analyzed. The screw can simplify the representation of rigid body motion,and has geometric intuitiveness and algebraic abstractness. Referring to the screw algebra and the influence coefficient theory,the screw velocity and acceleration mapping relation of the mechanism are given by adding virtual joint. Using polyline in the ADAMS software,the mechanism model is established,and the numerical validation is performed on the theory of kinematics modeling of the mechanism.关键词：Parallel mechanism;Screw algebra;Kinematics;Input selection
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发布时间：2022-10-20 - 摘要：The cylindrical gears international accuracy standard ISO 1328-1: 2013（ E） is revised on the old version ISO 1328-1: 1995. To clarify the influence of the latest cylindrical gear international accuracy standard on the gear strength standard GB/T 3480-1997（ idt ISO 6336-1 ISO 6336-3: 1996）,the relationship between the gear strength and the gear accuracy is analyzed,the allowable value of single pitch deviation,profile form deviation under the two versions of ISO 1328-1 is listed,and the difference percentage of the two pairs of the instance gears（ 4 gears in total） is calculated,including dynamic factor,transverse load factor（ contact stress）,calculated contact stress,factor of safety from pitting,calculated tooth-root stress,factor of safety from tooth breakage. The instance calculation results shows that the difference percentage of the calculation tooth root stress of gear a is 4. 86%,while gear b is 14. 12%. There is big difference between the two versions of the cylindrical gear international accuracy standards,which will contribute to gear strength calculation standard. More attentions should be paid by someone who using the related standards.
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发布时间：2022-10-20 - 摘要：Clamping force control is one of the key technologies of metal V-belt Continuously Variable Transmission（ CVT） control. The absolute safety coefficient method can guarantee the minimum system clamping force of no-load,but its clamping force margin is too large compared with traditional method. In order to reduce system clamping force,the clamping force fuzzy calculation method is proposed on the basis of absolute safety coefficient method. The mathematical model and simulation model of engine,CVT and vehicle are established,and the simulation test of starting condition,rapid acceleration condition,rapid deceleration condition and cycle condition show that the clamping force average decrease of about 5% and the fuel economy of complete vehicle through the fuzzy calculation of clamping force is improved.关键词：Continuously variable transmission;Clamping force;Safety factor;Fuzzy calculation
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发布时间：2022-10-20 - 摘要：The parallel-serial robot motion mechanism,compared to the single parallel mechanism,the working space can be largely increased and so as its deflexion capacity,there for,its application foreground is broad. A positional forward analysis solution of 2（3-RPS） parallel-serial robot motion mechanism is presented. Firstly,the position coordinates of spherical joints on the upper platform of 3-RPS parallel mechanism are derived based on its structural characteristics,and then,a set of equations are listed according to the fixed side value of motion platform of each parallel mechanism,using iterative transformation method,a 16 order equation with one unknown variable is gained. All its positional forward solutions can be precisely derived after the structure parameters of the parallel-serial mechanism are determined. At last,the numerical example is presented,and 32 positional forward solutions are gained at the specific structure parameters.关键词：2（3-RPS）;Parallel-serial robot;Forward solution;Numerical example
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发布时间：2022-10-20 - 摘要：A single-input three-DOF parallel manipulator controlled by cam is designed based on the parallel mechanism theory. And then the kinematics study is carried out,the analysis of the freedom of the manipulator is completed,the kinematic forward solutions and kinematic inverted solutions are worked out. On this basis,the parametric design of the cam is completed. Finally,by using the kinematics simulation with Pro/E,the correctness of the design is verified,the theoretical basis for the establishment of manipulator speed and acceleration model,workspace and singularity analysis is provided.关键词：Cam;Parallel manipulator;Kinematics analysis;Kinematics simulation
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发布时间：2022-10-20 - 摘要：According to the transmission efficiency of offset slider crank mechanism,based on the analysis of offset slider crank mechanism working stroke,the sum of unit invalid force in the working stroke is put forward to evaluate the mechanism transmission performance. The offset slider crank mechanism transmission angle function is derived,and the explicit analytical function equation for the sum of unit invalid force（ the symbol is） in the slow working-stroke is derived too. Combining with W function image and the W function characteristic is analyzed. Taking the slider crank mechanism of silver electrolytic cell for example,a detailed method of using W function in Matlab to optimize the design of the mechanism is stated.关键词：Offset slider crank mechanism;Transmission angle function;Working-stroke;Sum of unit invalid force;Matlab
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发布时间：2022-10-20 - 摘要：In order to improve fuel economy further within traction ability target,a Cruise-Isight Co-simulation model is established. By using multi-island genetic algorithm,the transmission gear ratio is optimized separately under certain traction ability and structural design constraints,a basic optimized scheme which can meets performance target is gotten. The gear ratio result from optimization model is adjusted according to drive comfort and structural requirements from the engineering point of view. Finally,the gear ratio is recommended which can meets traction and engineering requirements. After optimization,the traction performance reaches target closely and the integrated fuel consumption of NEDC cycle is reduced by 0. 23 L/100 km,3. 86%lower than the original scheme,and the ride comfort of the constant speed shift is improved also.关键词：Fuel economy;Cruise;Isight;Co-simulation;Transmission gear ratio optimization
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发布时间：2022-10-20 - 摘要：The tooth profile curve of double-arc common-tangent tooth profile harmonic reducer is established and the conjugate tooth profile fitting analysis for double-arc common-tangent tooth profile designed by enveloping theory is carried out. By using the ANSYS,the involute tooth profile and double-arc common-tangent tooth profile harmonic reducers are analyzed and compared,and the radial and tangential deformation of tooth profile under the condition of no load and loading of the two teeth profiles are analyzed. The results show that,the deformation of tooth profile of the double circular arc and involute tooth profile under the condition of no load is the same,after loading,the deformation of the double circular arc is less than that of the involute tooth profile and has larger bearing capability.关键词：Harmonic reducer;Double circular arc tooth profile;Involute tooth profile;Deformation analysis
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发布时间：2022-10-20 - 摘要：Aiming at the problem of wear on the spur gear of a type reducer,by the confocal laser scanning microscope,white light interferometer,the surface microtopography and microhardness of the gear are detected. The test results indicate that the surface of driven gear has irregular texture after nitriding,and surface roughness Ra is reached 0. 87 μm. The microhardness value of the driven is higher than the driving. The surface of driving has obvious pits and the surface roughness Ra is 0. 50 μm. According to test results,the main reason for the wear of driving surface is quite serious is that,the surface roughness and microhardness of the driven and driving not match either,the Abbott curve of the driven is superior to the driving.关键词：Spur gear;Gear surface microtopography;Microshardness;Wear process
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发布时间：2022-10-20 - 摘要：The rigid-flexible couple virtual prototype model of RV reducer which including machining errors,assembly errors,elastic deformation and clearance is established. The dimension and error variables of the virtual prototype model are parameterized. In order to determine the main factors,the transmission error curve of RV reducer under the action of different error factors is obtained. According to the main error factors,the orthogonal test is used to analyze the transmission precision of the RV reducer. The transmission accuracy of RV reducer is tested by grating method. The simulation model is modified and verified by comparing the simulation results with the experimental results.关键词：RV reducer;Virtual prototype;Error coupling;Transmission precision;Orthogonal test
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发布时间：2022-10-20 - 摘要：In order to obtain the natural frequency and vibration mode of the chain transmission system of the scraper conveyor,the meshing process of the sprocket and the round link chain is analyzed to obtain the key meshing state during the meshing process. The modal analysis of the different meshing states is carried out by ANSYS software. A general natural frequency change law in a complete meshing process is obtained,by the method of fitting data points and the natural frequency range of the chain transmission system is obtained.Which effectively solve the problem that single sprocket static mode analysis cannot meet practical condition.The solving results provide the basis for the dynamics research and optimization design of the chain transmission system of the scraper conveyor.关键词：Modal analysis;Chain transmission;ANSYS;Scraper conveyor
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发布时间：2022-10-20 - 摘要：The vibration of tapered roller bearings is affected by many factors,which belongs to the problem of poor information. Based on the theory of poor information system,by using a variety of correlation methods to analyze the influencing factors of different vibration values. The main influencing factors of each vibration value are analyzed by qualitative fusion,and then the main influencing factors of different vibration values are fused to obtain the main influencing factors of tapered roller bearing vibration. The experimental results show that the main factors affecting the bearing vibration under the measurement conditions are the roller base runout,the roller straightness,the roller diameter variation,the inner raceway roundness and the inner raceway verticality.关键词：Roller bearing;Correlation degree;Correlation sequence;Qualitative fusion;Factor analysis
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发布时间：2022-10-20 - 摘要：The contact pressure of the tooth surface of the polymer gear is analyzed by using the method of Hertz contact theory and finite element contact analysis. The calculation method of the tooth surface friction coefficient and the friction heat flux density of the gear tooth during the meshing process is studied. The simulation method of temperature field and stress in the instantaneous contact temperature of the gear teeth during the meshing transmission of PEEK polymer gear is discussed. The direct coupling method is used to analyze the heat-structure of the gears,and the transient temperature field and stress are obtained. The results of the initial ambient temperature are discussed. The results show that the increase of the initial ambient temperature has a great influence on the temperature field and the stress at the time of meshing.关键词：Polymer gear;Contact stress;Temperature field;Finite element analysis
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发布时间：2022-10-20 - 摘要：The probe is the key component of the precision measurement equipment,and the development of the new type of probe is the focus of the field of precision measurement technology. The existing research mainly focuses on improving the measurement theory and optimizing the sensor performance,and has little research on the structural innovation of the probe body. Based on the basic property of the mechanism that the parallel mechanism is located in the singular configuration,a new kind of parallel compliant probe is constructed by using the method of rigid body replacement. The line geometry and the null space method of the force Jacobian matrix are used to explain the function freedom of mechanism required for the 3D probe. Based on the statics of the parallel compliant support mechanism and the stiffness model of the branched chain,the overall stiffness matrix of the mechanism and the force-displacement model of the probe are established. Besides,the correctness of theoretical analysis is verified by numerical simulation and finite element software. The research content expands the application scope of the parallel compliant mechanism,enriches the structural innovation method of the precision probe constraint support mechanism,and lays an important theoretical foundation for further constructing the new probe based on the type of parallel compliant mechanism.关键词：Compliant mechanism;Parallel mechanism;Precision probe;Statics analysis;Static stiffness
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发布时间：2022-10-20 - 摘要：Based on the analysis of physiological structure and jumping movement characteristics of human lower limb,the jumping model of the lower limb is simplified as a plane multi-rigid body motion system. According to the forward kinetics analysis,the position,velocity and acceleration models of joints,centroids of each component are established. On the basis of the kinematics analysis,the dynamics analysis is carried out by using the Lagrange method,the dynamics equations of the relation between force and position in the jumping phase are obtained,the theoretical foundation for the design of various humanoid jumping mechanisms is provided. Finally,by using workbench,the statics analysis of the foot components in different phases is carried out,and the deformation and stress distribution of the sole are obtained.关键词：Lower limb;Jumping;Model simplification;Kinematics;Dynamics
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发布时间：2022-10-20 - 摘要：The abnormal noise quality problem is measured in off-line detection of a DCT250 dual clutch transmission. The fault phenomena is analyzed by ABA testing. The results show that gear direction helix angle error of second gear on external input shaft is strongly related with the NVH problems. Through the verification of the machining process of tooth to crossover,it is confirmed that the center hole of the input shaft head is not concentric with the A datum,which is the root cause of the gear direction helix angle error. Combined with the results of the test and analysis,the problem of abnormal quality of the noise is solved by controlling the spline alignment and detecting the full tooth profile periodically. Finally,the correctness of the analysis and the feasibility of the optimal scheme are verified by the final trend tracking. The analysis method of test not only shortens the processing time of NVH problem,but also has good reference value for solving similar engineering problem.关键词：Transmission;NVH;Noise quality;Concentricity
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发布时间：2022-10-20 - 摘要：The different structural helicoidal surface thrust bearing lubrication models is built and calculated with FLUENT to analyze the effects of the thickness of the oil film,pitch of the helicoidal surface and angular speed on load capacity of the thrust bearing,which provide the theoretical basis for design of helicoidal surface thrust bearing. The results show that with the increase of the pitch and oil film thickness,the maximum temperature of the oil film is decreased. The axial load capacity decreases with the increase of the oil film thickness.There is an ratio of pad height to the minimum film thickness which maximizes the load capacity when the minimum thickness of oil film and angular speed are constant,the best ratio of pad height to the minimum film thickness is 1. 4. The maximum temperature and load capacity of the oil film are linearly related to the angular speed. The load capacity of the helicoidal surface is much higher than the flat.关键词：Helicoidal surface;Oil film thickness;Load capacity
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发布时间：2022-10-20 - 摘要：The modal parameters of the gearbox have great influence on the vibration characteristics of the transmission and the whole machine. Combining with the finite element method and the testing technology,the free modal analysis and test of the XG958 H type excavator gearbox are carried out and modal parameters are obtained. The ANSYS Workbench analysis software is used to simulate the modal of the gearbox. At the same time,based on the LMS test and analysis system,the parameters of each stage of the gearbox are identified by the least square method. The results show that the results from the two methods are basically the same and the maximum error is 7. 54%,which verifies the reliability of the LMS experimental method and the ANSYS Workbench simulation,and the reference to avoid the resonance frequency when the gearbox is working is provided.关键词：LMS;ANSYS Workbench;Free modal;Gearbox
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发布时间：2022-10-20 - 摘要：The magnetic-geared double-rotor permanent magnet motor is fused permanent magnet brushless DC motor and field modulated magnetic gear,which is a kind of low speed and high torque direct drive motor. It has opened up a new idea for improving the motor efficiency and torque density. It is an urgent problem to be solved that establish the electromechanical dynamics model and high-performance control of the kind of component. It is intended to establish the electromechanical coupling dynamic analysis model,and grasp the law that is the influence of controller parameters for driving system performance. Starting from the principle of motor operation,the motor can be decomposed into a brushless DC motor that is equivalent to high speed rotor and armature,and a magnetic gear equivalently that to the double rotor assembly considering elastic effect. The two part is combined of high-speed rotor. The numerical model of the motor is built in MATLAB/Simulink,and the system is regulated by using the PID control. Although the simulation results show that although there are the problems of nonlinear and coupling in the system,the tuned PID control can make the system track the input signal and achieve comprehensive performance index well.关键词：Magnetic-geared motor;Dynamics model;PID control;Parameter setting
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发布时间：2022-10-20 - 摘要：The traditional coupled and self-adaptive fingers realize firstly coupling and secondly self-adaptive hybrid grasping mode with three springs and two sets of independently transmission mechanisms,which have disadvantages of complexity in mechanisms,huge consuming in power,and difficulty in spring selection.Aiming at the problem,a novel coupled and self-adaptive underactuated finger mechanism,called COSA-LET finger is designed. The COSA-LET finer includes multiple racks,two toggle blocks,two limiting blocks,and two springs,which has two joints driven by one motor and a serial transmission mechanism. The coupling function of COSA-LET finger is realized by two opposite-direction racks,and a gear with a spring and a limiting block,the de-coupling problem of the finger in the self-adaptive stage is solved by dividing torque of the motor into two joint shafts with a spring and the delay-ticking transmission effect of two toggle blocks in linear empty-trip racks. Grasping force analysis and experimental results show that the COSA-LET robotic hand with three COSA-LET fingers has the coupled and self-adaptive hybrid grasping function,enable to adapt objects of different shapes and sizes,autonomously switch between the coupled mode and the self-adaptive mode.关键词：Robot hand;Underactuated finger;Self-adaptive mechanism;Hybrid grasping;Linear empty-trip transmission
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发布时间：2022-10-20 - 摘要：Aiming at constant torque output,the constant-torque control strategy of power-shift is proposed. Based on constant-torque control strategy,considering diesel engine speed characteristics and the practical needs of tractor under load condition,the practical control strategy of power-shift is proposed for high-powered tractor. The power-shift process is divided into two periods,which are speed synchronization period and power transfer period respectively. Power transfer period comes first and speed synchronization period comes later when power-shift-up,while speed synchronization period comes first and power transfer period comes later when power-shift-down. Based on the two periods of power-shift,the relationship between actuating pressure of oncoming and off-going clutches and the principles for upper-limit of actuating pressure during power-shift are presented. Based on MATLAB/Simulink,power-shift process is modeled and simulated. The results show that the practical power-shift control strategy can realize no power break and large consistent torque output during shift without coordinating engine,so that the high-powered tractor can adapt to the changes of working resistance and operate continuously without stopping,which improves operation efficiency.关键词：High-powered tractor;Power-shift;Constant-torque control strategy;Practical control strategy;Power transfer;Speed synchronization
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发布时间：2022-10-20 - 摘要：The planetary gear system of lifting platform has special and complicated working conditions.Based on the principle of gear multi-body contact dynamics and transmission system,a dynamics virtual prototype model of the system is established to obtain the dynamic meshing force. By using the mathematical statistics known probability density distribution is complex,the dynamic meshing force can’t meet the normal probability distribution assumption,traditional reliability analysis methods not applicable. Therefore,using rejection sampling method is proposed in line with the original mesh of arbitrary distribution of random numbers,to truly reflect the reliability level. The combined dynamics simulation and Monte Carlo method are presented to illustrate the effectiveness of the proposed method.关键词：Planetary gear system;Adams;Rejection sampling method;Monte Carlo;Reliability
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发布时间：2022-10-20 - 摘要：A small modulus spline checking fixture is developed. The checking fixture has eccentric cam structure and designed by parameterization method. The checking fixture structure and method of application is explained,the parameterization automatic measurement and the result comparison are carried out.关键词：Involute spline;Over pin distance;Parametrization design;Eccentric cam;Checking fixture;PC-DMIS;Automatic measurement
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发布时间：2022-10-20 - 摘要：Morgan RSM has been pervasive applicated on high speed wire rod production for its compact-sized,high quality products,high productivity,and so on. The speed ratio with different manufacturing technique requirements can be combined by adjusting 9 clutches. The gears used in which,worked with tapered roller bearings with pre-tightening force. The reliability of the equipment would be seriously reduced by off-gear caused by the abrasion of bearings under the working condition. A localization improvement on rolling bearing units of RSM on high speed wire rod production is described,which would be available for similar project.关键词：RSM;Reliability;Localization
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发布时间：2022-10-20
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