最新刊期
卷 48 ， 期 4 ， 2024
- 摘要：With the development of the gear transmission system towards complexity, multiple transmission types and high reliability, it becomes more and more important to assign the reliability of the gear transmission system quickly and accurately. In this study, aiming at the problems of incomplete consideration factors, inconsistent range of changes in different allocation methods for the same parameter, and inconvenient digital software development in existing reliability allocation methods, an improved advisory group on reliability of electronic equipment (AGREE) allocation method is proposed, the scoring allocation method is extended, and the digital characteristics of reliability allocation method are discussed. The basic reliability model and task reliability model of the complex gear transmission system are established, and the traversal algorithm of the automatic reliability model generation is studied. A digital platform for rapid reliability allocation of fixed axle gear train, planetary gear train and hybrid gear train is developed. Four independent modules, namely input module, calculation module, result display module and output module, are designed. The accuracy of the calculation results of the software is verified by comparing with the results of examples. The parametric modeling and the automatic generation of the example report for the reliability allocation of the gear transmission system are realized, and the accuracy and efficiency of the reliability allocation model are raised.关键词：Gear transmission;Parametric modeling;Reliability allocation;Digital design;Power split
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发布时间：2024-04-19 - 摘要：In order to deeply study the influence of parallel misalignment failure on fatigue life of pin couplings with elastic sleeves, on the basis of transient dynamic analysis, the influence of different degrees of parallel misalignment on fatigue life is obtained. Based on transient dynamic fatigue analysis data, combined with the differential autoregressive integrated moving average (ARIMA) model, the fatigue life prediction of pin couplings with elastic sleeves is realized. The results show that the minimum fatigue life of pin couplings with elastic sleeves decreases with the increase of the degree of parallel misalignment, and when the degree of parallel misalignment is less than 2.63%, the decrease of minimum fatigue life increases gradually. The predicted fatigue life of 4.74% parallel misalignment is 1.214 0×106, and the relative error between the predicted value and the simulation value is 0.22%, indicating the reliability of the ARIMA model in predicting fatigue life. The research results can provide guidance for the anti-fatigue optimization design of pin couplings with elastic sleeves.关键词：Pin coupling with elastic sleeve;Parallel misalignment;Transient dynamics;Fatigue life
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发布时间：2024-04-19 - 摘要：Aiming at the problem of subjectivity and uncertainty in the configuration and selection of spherical robot design schemes in multi-demand unstructured environments, a scheme evaluation method coupled with fuzzy rough number and complex proportional assessment (COPRAS） is proposed. Considering the importance relation between different demand characteristic indexes in scheme design, the quantitative analysis of demand characteristic indexes is realized based on the fuzzy rough number. The COPRAS method is used to comprehensively evaluate all alternative design schemes, the priority ranking of all alternative design schemes is obtained according to the utility index to determine the optimal configuration scheme， and the selection of deformed spherical robots is taken as an example for evaluation and verification. The research results show that the method has good reliability and practicability, which provides effective reference for the configuration and selection of the robot design scheme in the future.关键词：Spherical robot;Fuzzy rough number;COPRAS method;Scheme configuration
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发布时间：2024-04-19 - 摘要：Gear skiving has been paid more and more attention for high efficiency and wide application in gear manufacturing. In gear skiving, prediction of cutting temperature and optimization of process parameters have an important influence on increasing tool life, improving machining quality and decreasing residual stress. In this study, firstly, according to the kinematic theory of gear skiving, the entity models of the skiving tool and the workpiece are established, and then the cutting temperature nephograms on the rake face of single tooth during the cutting process are obtained based on Deform software. Secondly, aiming at the influences of the cutting velocity, feed rate and shaft angle on the maximum cutting temperature on the rake face, the prediction model of the cutting temperature under multiple parameters is established by response surface methodology. Finally, a method of process parameter optimization is proposed to maximize the machining efficiency with the constraint of cutting temperature. Combined with three groups of optimization examples, the validity of the cutting temperature prediction model is verified by comparing the error between the predicted values and simulation results under the optimized parameters. The results show that the shaft angle has the greatest effect on the cutting temperature under single parameter, the cutting velocity-shaft angle has the greatest effect on the cutting temperature under multiple parameters, and the optimized predicted values are within a reasonable error range from the simulation results. The results of this study provide methodological support for improving the machining quality and tool life in gear skiving.关键词：Gear skiving;Cutting temperature;Process parameters;Finite element simulation;Parameter optimization
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发布时间：2024-04-19 - 摘要：A study on the load characteristics of the modified gear planetary gear systems is conducted to address the issue of uneven loads between planetary gears due to manufacturing and installation errors, which result in deviations between the radial and circumferential installation positions of planetary gears and non-offset values. Based on the theory of rotor dynamics, the time-varying stiffness and the radial and circumferential offsets of the planetary gears are considered, and the five-degree-of-freedom dynamic model of the planetary gear transmission system with addendum modification is established. The response and frequency spectrum of the system are solved by the Runge-Kutta method. The load distribution characteristics of the planet gears under different radial offsets, circumferential offsets, and comprehensive offsets are analyzed. The influence of the radial and circumferential offset of the planetary gear on the load distribution of the planetary gear transmission system is discussed, and the variation law of the load vibration amplitude of the planetary gear transmission system with addendum modification under the time and frequency is obtained. The simulation results show that the load characteristics of the planetary gear train considering the error are quite different from those in theory. Its vibration amplitude of the planetary gear transmission system is greatly affected by the radial offset, and the large radial offset has the greatest impact on the load of the planetary gear. Small deflections of the planetary gear during installation can lead to large changes in the load characteristics. The planetary gear transmission system load test platform is built, the frequency-doubling vibration response signal of the planetary reducer housing is tested, and the relation between the planetary gear transmission system load force and vibration response is obtained. The amplitude variation trend in the experimental results is similar to that in the simulation analysis, and the correctness of the established model and solution method is verified.关键词：Addendum modification gear;Planetary gear transmission system;Time-varying stiffness;Load characteristic
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发布时间：2024-04-19 - 摘要：The problem of estimating the gripping force of surgical instruments has been the focus of research on minimally invasive surgical robotic surgical instruments. During the minimally invasive surgery, excessive gripping force can cause tissue damage, and too small gripping force can make suture needles fall off and cause danger. Therefore, it is necessary to study how to estimate the gripping force of surgical instruments. According to the structural characteristics of surgical instruments, a method for estimating gripping force based on dynamic model is proposed. The dynamic model of the surgical instrument, the force and displacement transmission characteristics of the cable driven system and the direct-current motor characteristics are considered in the established model, and the relation between the surgical instrument motor current and the gripping force is obtained. The gripping force model is validated by using Matlab simulation, and the gripping force variation curve of the surgical instrument end-effector with the change of the motor current are obtained. The simulation results show that the gripping force estimation model of the surgical instrument based on the dynamic model is consistent with the actual situation, which provides a theoretical basis for the subsequent research on the gripping force security of the surgical instrument.关键词：Surgical instrument;Dynamic model;Cable drive;Gripping force
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发布时间：2024-04-19
Theory·Research
- 摘要：Aiming at the balance between the accuracy, stability and exoskeleton volume of the existing upper limb exoskeleton, an 8-degree-of-freedom （DOF） hybrid upper limb rehabilitation exoskeleton robot is proposed. A new 2-degree-of-freedom elbow rehabilitation device is designed to replace the traditional single-degree-of-freedom elbow exoskeleton in order to better achieve elbow training for patients with upper limb movement disorders. A 3RRR/S mechanism with coaxial spherical surface is designed for hand rehabilitation, which can make the rehabilitation training of hand more enveloping. The coordinate system is established according to the hybrid exoskeleton mechanism, the kinematic model of the rigid body part of the mechanism is established by using the vector loop method, and the working space nephogram of the mechanism is drawn by Monte Carlo method to verify that it meets the space requirements for rehabilitation training. Finally, the trajectory planning of a typical motion is carried out by Matlab, and the smooth trajectory of the terminal centroid motion is obtained by Adams to verify the rationality of its kinematic analysis and structural design. The maximum load attitude is simulated by constrains the excess degrees of freedom, and the load characteristic curve is drawn, which lays the foundation for the selection of the drive and the construction of the prototype.关键词：Rehabilitation training;Rehabilitation of exoskeletons;Kinematics simulation;Hybrid mechanism
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发布时间：2024-04-19 - 摘要：In the rehabilitation training process of lower limb rehabilitation robots, the existence of uncertain factors such as model parameters and environmental interference will affect the accuracy of trajectory tracking of the robot. To solve this problem, an adaptive compensation control based on the radial basis function (RBF) neural network is proposed. This control method can improve the accuracy of mechanical system trajectory tracking. Firstly, a closed chain horizontal lower limb rehabilitation robot structure with four working modes and stable movement is designed. Secondly, the Lagrange method is used to solve the kinetic nominal model, the uncertainty factors such as model parameters and external interference of the rehabilitation device are separated, and the adaptive compensation algorithm based on the RBF neural network is designed for the approximate control. Finally, the Matlab/Simulink environment is used to verify the effectiveness of the control strategy. The results show that, compared with the traditional fuzzy proportional integral derivative (PID) control method, the adaptive compensation algorithm based on the RBF neural network has a faster response speed and better tracking effect in human gait curve trajectory tracking. Moreover, the peak angle errors of the hip joint and the knee joint trajectory tracking are 0.08° and 0.13° respectively, which are much less than the rotation angle of patients' lower limbs in rehabilitation exercise. A single-leg prototype experiment is designed to show that the RBF compensation adaptive controller used in the study can achieve high precision tracking results and meet the safety requirements of patients in rehabilitation training.关键词：Lower limb rehabilitation robot;Closed chain structure;RBF neural network;Uncertainty Adaptive compensation control
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发布时间：2024-04-19 - 摘要：A 3-RPS parallel leveling mechanism based on the proportional integral (PI) robust sliding mode system is designed to solve the problem of data acquisition inaccuracy caused by vehicle tilting during the robot walking. Firstly, the configuration synthesis is carried out according to the spiral and inverse spiral theory. Then, the dynamic analysis and calculation of the 3-RPS leveling mechanism are carried out to construct its dynamic model. On this basis, the adaptive robust sliding mode algorithm is introduced to optimize and improve the PI controller to improve the stability and adaptive correction ability. The stability of the nonlinear control system is verified by Lyapunov function. Finally, the control error curve is obtained by Matlab/Simulink comparative simulation experiment. The simulation results show that the adaptive correction effect of the PI control system optimized by the robust sliding mode algorithm is remarkable, and the steady-state error of the control is greatly reduced. The research provides a basis for the development of physical prototype of 3-RPS parallel leveling mechanism.关键词：3-RPS leveling mechanism;Dynamic analysis;Nonlinear control;Lyapunov function
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发布时间：2024-04-19 - 摘要：A 3-DOF parallel manipulator with X, Y movement and Z rotation for the end-effector is studied in order to meet the requirements of copying and polishing of louver blades. In order to verify the kinematic performance of the manipulator, firstly, the mechanism characteristics are described, and the degree of freedom of the mechanism is analyzed based on the spiral theory. Secondly, the kinematics equations of the mechanism are constructed based on the closed-loop vector method, the forward and inverse position solutions are analyzed, and the analysis results are preliminarily verified by concrete examples. Finally, the numerical simulation model and virtual prototype model of the mechanism are constructed, and the inverse kinematics simulation analysis of the position and velocity is carried out. The simulation results show that the analysis results of the two models are consistent, and the result of inverse solution is reliable. The arm chain can coordinate the movement, the movement process is smooth, and the displacement and velocity curves are smooth and without mutation, and can provide a basis for the size optimization and motion control of the manipulator.关键词：Parallel manipulator;Spiral theory;Kinematics;Virtual prototype
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发布时间：2024-04-19 - 摘要：In order to better meet the work requirements of the marking production line to remove the unqualified workpieces, this study designs a double cam clamping mechanism which can realize the clamping and lifting of the workpieces with only one power source. The motion sequence of two cams is designed based on the action sequence of clamping and removing the unqualified workpieces. The contour curve of the cams is calculated by Matlab software, and the 3D model is built on SolidWorks platform. Adams software is used to complete the parametric modeling and motion simulation of the double-cam clamping mechanism. The results show that the output motion law of the mechanism is consistent with the designed motion law. Through the optimization design of the key coordinate position, the appropriate position parameters of the key coordinate are obtained. The double-cam clamping mechanism can effectively save cost and improve work efficiency, and has certain theoretical value and high application value for practical production line.关键词：Marking production line;Cam;Clamping mechanism;Simulation optimization
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发布时间：2024-04-19 - 摘要：In order to correctly understand the output characteristics of gear-motors with different types of backlash sizes/offset unloading slots, a unified simplified formula for output characteristics such as speed/torque is constructed based on the different meshing line intervals of meshing tooth profiles/output characteristics, using the type value that measures the backlash size and the offset value between the symmetrical line of the double unloading slots and the centerline of the gear pair as variables. The results show that through the interval of the output characteristic meshing-line, the output speed and torque curve can be directly obtained from the speed and torque curve of meshing tooth-profile; under the symmetrical relief-groove type, the average output speed is the smallest, the average torque is the biggest, and the ripple coefficients of the output speed and torque are the smallest; the offset range of the relief-groove and the range of the output speed and torque regulating are larger under small backlash type than large backlash type; with small backlash and symmetrical relief-groove type, the average output speed is smaller, the average output torque is larger, and the ripple coefficient of the output speed and torque is smaller; the torque-ripple coefficient of the gear-motor is completely consistent with the flow-ripple coefficient of the gear-pump; the torque-ripple coefficient is slightly less than the speed-ripple coefficient, and can be approximately equal under the condition of large tooth-number; when high-speed is pursued, the type combination of large backlash and relief groove limit-offset shall be selected; with the pursuit of large torque or high output ripple-quality, the type combination of small backlash and symmetrical relief-groove shall be selected, etc. It is concluded that the obtaining method of output characteristics is simpler, the principle is clearer, the form is more concise, and the results are more reliable.关键词：External gear-motor;Backlash;Relief-groove;Meshing-line interval;Output speed and torque;Ripple coefficient
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发布时间：2024-04-19 - 摘要：A wearable walking aid for lower limbs is designed, which is mainly used to assist patients with lower limb movement disorders such as stroke hemiplegia to carry out daily walking activities. First of all, based on the analysis of the lower limb motion mechanism, joint structure and the composition of degrees of freedom, the three-dimensional structure model of the lower limb wearable walker is established. The 3D infrared motion capture system is used to collect the gait data of normal people and fit the corresponding joint angle curve. The simplified D-H model of the walker is established, and the kinematics modeling analysis of the walker is carried out. Taking the gait data collected from the motion capture experiment as the simulation driving force, the kinematics simulation verification of the walker is carried out. The results show that the joint angle change curve is basically consistent with the angle curve collected from the experiment, and the angular velocity change curve and the ankle joint centroid position change curve are consistent with the normal human walking law, which verify the rationality of the structure design of the lower limb wearable walker.关键词：Lower limb wearable walking aid;Mechanism of lower limb movement;Motion capture experiment;Kinematic modeling;Kinematic simulation
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发布时间：2024-04-19
Design· Calculation
- 摘要：Gear surface damage is an important factor affecting gear transmission. It is extremely important to improve the efficiency and accuracy of gear surface damage identification. ResNet recognition model of gear surface damage is established based on Pytorch architecture, dataset is expanded by means of data enhancement, model training is optimized by means of transfer learning, and four ResNet structures are compared. The results show that the dataset composed of 640 images after the enhancement of 64 original image is not enough to meet the needs of model training for a large amount of data; using transfer learning can improve the speed and accuracy of model training, and meet the requirements of gear surface damage identification; the ResNet-101 model is the optimal structure in this framework. This research has important scientific significance and engineering value for the recognition of gear surface damage.关键词：Convolutional neural network;Gear surface damage;Deep learning;Transfer learning
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发布时间：2024-04-19 - 摘要：Based on the thread tooth load distribution of the inverted planetary roller screw mechanism（IPRSM）, the influence of roller modification and screw modification on the load distribution is analyzed. The results show that the uneven load on the screw-roller interface is more serious than that on the long nut-roller interface, and the maximum contact stress and the maximum load on the threaded teeth are effectively reduced by the roller modification. Besides, the long nut-roller interface is more sensitive to the modification amount than that of the screw-roller interface. Similarly, the maximum load can also be effectively reduced by the screw modification. This study has some reference significance for optimizing the load distribution of the IPRSM.关键词：Inverted planetary roller screw mechanism;Threaded tooth modification;Load distribution Finite element analysis
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发布时间：2024-04-19 - 摘要：The stiffness and damping characteristics of the diaphragm coupling are the basis for analyzing the vibration characteristics of the shafting system with the diaphragm coupling. Based on Ansys finite element simulation software, considering contact nonlinearity and large deformation effects, this study simulates and analyzes the torsional, axial, angular and radial static stiffness characteristics and torsional and axial dynamic characteristics of the diaphragm coupling, and analyzes the influence of the diaphragm structure parameters such as the diameter of the bolt hole distribution circle, the diameter of the bolt hole, the minimum width of the diaphragm and the thickness of the diaphragm on the static stiffness. Finally, static, dynamic torsion and axial tension tests are carried out to verify the correctness of the simulation results. The results show that the diameter of the bolt hole distribution circle and the thickness of the diaphragm have a greater influence on the anisotropic stiffness of the diaphragm. The dynamic model of the diaphragm coupling can be better established through the quasi elliptic function. The nonlinear stiffness and the equivalent damping coefficient changes in a period of the diaphragm vibration can be obtained.关键词：Diaphragm coupling;Finite element;Stiffness;Damping
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发布时间：2024-04-19 - 摘要：Three kinds of circular spline materials are studied for harmonic reducers, stainless steel 2Cr13, medium carbon alloy steel 40Cr, carbon 45 steel. Through the analysis of microstructure, hardness, three-dimensional and two-dimensional morphology in microwear and friction coefficient, the differences in wear resistance of different materials are attained. The results show that the microstructures of 2Cr13 and 40Cr are tempered sorbite, and the microstructure of 45 steel is ferrite and pearlite. The hardness of the 2Cr13 and 40Cr is similar and much larger than that of the 45 steel. The morphology of 2Cr13 is adhesion and spalling, and the wear mechanism is adhesion wear. The morphology of 40Cr and 45 steel is furrow and spalling, furrow and adhesion, and the wear mechanisms are abrasive wear. The friction coefficients' differences of the three materials are negligible, and the area of wear of 2Cr13, 40Cr and 45 steel are 5 008 μm2, 1 645 μm2 and 6 535 μm2. 40Cr exhibits better wear resistance than 2Cr13 with similar hardness. The hardness difference between 45 steel and the friction pair material is the largest, and the wear resistance of the 45 steel is the worst.关键词：Harmonic reducer;Circular spline materials;Wear mechanism;Wear resistance
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发布时间：2024-04-19 - 摘要：Aiming at the problem that it is difficult to explore the contact state law of racks and pinions under the condition of rack-rail train wheel tread wear, a calculation model of rack and pinion tooth surface contact stress considering wheel tread wear is proposed based on the Hertz contact theory. Firstly, the contact relationship of racks and pinions under wheel tread wear is analyzed, the change law of key parameters of contact stress calculation with wheel wear is obtained, and the contact stress calculation model of racks and pinions considering wheel wear is constructed in combination with the Hertz contact theory. Then, the rack and pinion parameters of an engineering are selected for calculation, the tooth surface contact stress distribution in the wear cycle is obtained, and the contact stress data of the pinions and racks and of different wear quantities and different contact positions are obtained through 27 sets of finite element simulation tests, which are compared with the above calculation model results. Finally, the above calculation model is used to further analyze the internal mechanism and key factors of wheel wear affecting the contact stress law. The results show that the maximum relative error between the model results and the simulation calculation results is 7.71%, which verifies the accuracy of the calculation model. The greater the wear of the wheel tread is, the greater the contact stress near the meshing entry point of the rack and pinion will be; and the influence mechanism is that the radius of curvature of the drive gear near the meshing entry point is sharply reduced by wheel wear. Increasing the initial center distance and the rack tooth top fillet influence coefficient can reduce the influence of the wheel tread wear. The height adjustment period can also be appropriately reduced to optimize the contact state situation.关键词：Rack-rail train;Wheel tread wear;Rack and pinion;Hertz contact;Tooth surface contact stress;Theoretical calculation
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发布时间：2024-04-19 - 摘要：Aiming at the demand of electric cinch and release priority function of high-end vehicle door latches, a cam swing linkage and spring linkage combined mechanism is proposed, and a combined mechanism of double cam single swing linkage and spring four bar mechanism is constructed. Combined with the characteristics of limiting blocks, contact states, cam intermittent movement, profile abrupt change and other components, it can realize three motion modes of flexible and adaptive rolling, rigid pushing, avoiding and releasing, and switch among them. Embedded into the ratchet and pawl locking mechanism, the combined mechanism is transformed into electric cinch and release branches, corresponding to the three working conditions of the vehicle door latch: electric cinch, manual or power release and reset, and cinch branch reset. Based on the corresponding driving modes and motion boundary conditions, the compatible function of the cinch motion and the existing branches in the latch, the release priority function, and the half-lock release function in the case of the cinch pinch are studied and analyzed. The mechanism and the drive are embedded in the door latch for simulation, and the contact force between the release cam and the swing linkage, the swing linkage and the ratchet, and the ratchet and the paw are studied in all working conditions. The time of the mechanism to realize each function matches the design requirements of the vehicle door latch, the time of the electric cinch process is 420.97 ms, the reset time is 29.03 ms, and the manual release time is 622 ms.关键词：Vehicle side-door latch;Cam swing linkage and spring linkage combined mechanism;Multi-motion mode;Ratchet and pawl;Contact force
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发布时间：2024-04-19
Test·Analysis
- 摘要：Torsional vibration of the automobile transmission system may cause roar or abnormal noise in the car. Torsional vibration excitation generally comes from the main order of the engine and is transmitted to the gearbox through torsional vibration damper. Therefore, the torsional amplitude of the gearbox input shaft is the first factor to control the torsional vibration of the whole transmission system. A passenger car is equipped with a 6-speed wet double clutch transmission (WDCT). The maximum torsional amplitude of the input shaft of the gearbox from 2nd gear to 6th gear has reached 494.38 rad/s2, which does not meet the design requirement of 400 rad/s2. In order to solve the problem that the torsional amplitude of the gearbox input shaft is too large, this study uses AMESim software to build a torsional vibration analysis model with dual mass flywheel torsional vibration damper under full throttle driving condition, taking the engine speed fluctuation signal collected by a real vehicle as the excitation source. Through simulation analysis, the influences of the primary mass moment of inertia, secondary mass moment of inertia, torsional stiffness, basic damping torque and free rotation angle of the dual mass flywheel on the torsional amplitude of the gearbox input shaft are determined, and the optimization scheme of the transmission system is obtained through orthogonal experimental design, and the effectiveness of the optimization scheme is verified by a real vehicle. The research methods and ideas of this study provide a solution for the torsional vibration optimization of the automobile transmission system with dual mass flywheel torsional vibration damper.关键词：Torsional vibration;Dual mass flywheel;AMESim simulation;Orthogonal experiment
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发布时间：2024-04-19 - 摘要：When a gearbox transmission system fails, the multi-scale mean permutation entropy （MMPE） of different vibration signals corresponds to the fault state to a certain extent. However, the effect of multi-scale mean permutation entropy extraction fault features depends on the selection of parameters. Therefore, this study proposes a gearbox fault identification method based on the improved multi-scale mean permutation entropy and the parameter optimization support vector machine（SVM）. Firstly, the particle swarm optimization （PSO） is referenced to optimize parameters of multi-scale mean permutation entropy. Secondly, the multi-scale mean permutation entropy of the collected gear vibration signals is calculated.Finally, the particle swarm optimization is used to optimize the support vector machine to identify the fault state of the gear. Experimental analysis results are conducted to validate the effectiveness of this proposed method.关键词：Multi-scale mean permutation entropy;Particle swarm optimization algorithm;Support vector machine;Fault diagnosis;Gear
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发布时间：2024-04-19 -
Research and Manufacturing of Wrist Joint Rehabilitation Robots Based on the 3-UU Parallel Mechanism
摘要：Based on the 3-UU parallel mechanism, a prototype robot for wrist joint rehabilitation is developed to assist stroke patients in wrist joint rehabilitation training. Based on the constraint relation and geometric characteristics of the 3-UU mechanism, the inverse kinematics of 3-UU mechanism is analyzed by spherical coordinate method and roll-pitch-yaw (RPY) method， and the relation between the platform and the driver is obtained. Compared with the classic 3-RRR wrist joint rehabilitation mechanism, the developed prototype has no advantages such as multi-solution and singular value. The motion performance of the prototype and the electromyographic signals of the two major muscle groups in the forearm are measured. The experimental results show that the maximum roll angle is -90° to 90°, the pitch angle is -90° to 90°， and the virtual yaw angle is -180° to 180°. The maximum electromyogram (EMG) signal can be generated at 950 mV. The results show that the developed model can meet the requirements of the wrist motion and train the forearm muscle group.关键词：Wrist joint training;Parallel mechanism;Inverse kinematics;Rehabilitation robot- 1
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发布时间：2024-04-19 - 摘要：Based on the analysis of the overall structure of the existing hub motor used for electric bicycles, aiming at the problems of instability and large noise when the inner rotor of the hub motor adopts the left and right half shaft structure, a hub motor structure of the through shaft inner rotor and reduction device is improved and designed. Based on the optimization design theory, the minimum total volume of the reduction device is taken as the objective function to optimize. Creo software is used to draw the optimized 3D model of the reducer, and finite element analysis is carried out by Ansys Workbench software to check the strength and stiffness of the structure. The results show that the new design overcomes the defects of the left and right half shaft in the electric bicycle hub motor, the volume of the reducer is reduced by 8.6% after optimization, and the structural design strength and stiffness meet the requirements, which verifies the rationality of the structure, and provides a new idea and theoretical basis for the electric bicycle hub motor structure design and optimization.关键词：Through shaft inner rotor;Hub motor;Reducer device;Optimization design;Finite element analysis
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发布时间：2024-04-19
Development·Application
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