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Table of Content

    25 July 2018, Volume 29 Issue 14
    Ultrasonic Method and System for Automatic Detection of Cartridges
    WANG Zhe;MENG Jie;CUI Ximing;KANG Yihua
    2018, 29(14):  1639-1644. 
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    A method to detect micro cracks in different specifications of cartridges was proposed based on the constant shear wave refraction angle of busbar incidence.The reliability was verified by the simulation and experiment.Multi-station high-speed ultrasonic testing system for small-diameter cylinder,such as cartridge,was designed.A scanning signal filtering algorithm was proposed according to the signal features of defects and interferences.Finally,the automation of the whole processes,such as feeding detecting and sorting were realized.The results show that the system may detect the minimum crack depth of 0.05 mm, the detection speed is 1 200 pieces/h,and the misjudgment ratio is only 1%.
    Uncertain Optimization of Torsional Vibration Damper Considering Tolerant Design
    HAO Yaodong1,2;HE Zhicheng1;LI Guangyao1;ZHANG Zhuomin1
    2018, 29(14):  1645-1652,1660. 
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    The driveline model with torsional vibration damper was build and the relationship of driveline and rear axle were considered in this model.The vibration equation of the model was formulated.The influence of torsional vibration damper on the free and forced vibration of driveline was systematically studied.The interval uncertain optimization model was introduced to the driveline vibration analysis.With the presented method, the torsional vibration damper can play its role effectively in different manufacture and use conditions with greater tolerances.
    Influence of Plastic Deformation on Signals of Magnetic Incremental Permeability for Carbon Steel
    LI Lijuan1,2,3;XIE Shejuan1,2;CHEN Hong'en1,2;CHEN Lingli1,2;HE Manru1,2;CHEN Zhenmao1,2
    2018, 29(14):  1653-1660. 
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    Concerning the plastic deformation of carbon steel used in nuclear power plants,in order to investigate the influence mechanism of plastic deformation on the signals of magnetic incremental permeability,the characteristic quantities of B-H curve was adopted into the simulation to indirectly analyze the influence mechanism of plastic deformation on signal curves of magnetic incremental permeability.Simulation program was developed based on the reduced magnetic vector potential method,and the influences of residual magnetism and coercivity on magnetic incremental permeability signal curves were investigated by numerical simulation. The results indicate that the residual magnetism and coercivity may affect the peak separation,peak value and zero crossing of magnetic incremental permeability signal curve,which has reference value for the quantitative nondestructive evaluation of plastic deformation.
    Effects of Double-layer Groove Texture on Lubrication Performance of Machine Tool Slideway Surfaces
    ZHANG Dongya1,2;ZHAO Feifei1,2;GAO Feng1,2;DUAN Jihao1,2
    2018, 29(14):  1661-1665. 
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    Hydrodynamic effects of groove texture surface were studied by designing a double-layer groove texture model.The results show that when the volumes of single-layer and double-layer groove texture are the same,average oil film pressure of the double-layer groove texture is 2.31 times of that of the single-layer groove texture.Setting the dimensionless depth β1 and the first layer dimensionless width α1 of the double-layer groove texture as a constant,the average oil film pressures increases at first and then decreases as the increasing of the second layer dimensionless depth β2.The maximal value of the average oil film pressure may be obtained at the β2  equals to 4.4.When the dimensionless width α2 of the second-layer groove increases from 0.25 to 0.45,the vortex area in the groove also increases,and the average oil film pressures decreases gradually.
    Response Characteristic Analysis of Nonlinear Vortex-induced Vibration of Tension Leg Platform in Deep Sea
    SUN Yougang1,2;DONG Dashan1;QIANG Haiyan1,2;WANG Ran1
    2018, 29(14):  1666-1673. 
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    An improved dynamic model was presented for the nonlinear dynamics of tension leg of deep sea platform. Galerkin method and finite difference method were utilized to calculate for the proposed model,the responses of vortex-induced vibration of the TLP under the combined action of wave, current,pre-tension,platform motion and other complex loads were researched.The simulation results  show the dynamic mechanism of TLP working in complex sea environment.The results may provide references for the design and research of deep sea platform.
    An Identification Method of Hybrid Dynamics System for Biped Robots Based on Neural Network
    WU Xiaoguang1;ZHANG Tianci1;WEI Lei1;LI Yanhui1;WANG Tingjin1;ZHANG Bo2
    2018, 29(14):  1674-1681. 
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    In view of difficulties in identification of hybrid dynamics system for biped robots,identification conditions for continuous and discrete hybrid system in terms of asymptotic stability were analyzed and deduced.And then,a joint identification method was proposed based on combination of radial basis function neural network optimized by chaos particle swarm optimization and dynamic fuzzy neural network.Radial basis function neural network which was optimized by chaos particle swarm optimization to identify continuous swing stages,and dynamic fuzzy neural network was used for discrete collision stages.According to the same variable's coupling and transition relationship during two phases,the accurate identification for hybrid systems of biped robots was realized.The simulation results show that,the identified and predicted results are of high precision in this method.
    Rotating Mechanism Eccentricity Measurement Based on Error Iteration
    CHEN Bin;ZHANG Yang;GUO Xian;GAO Dewei;GAO Jianshu
    2018, 29(14):  1682-1687. 
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    For the problems of existing eccentricity measuring method systems sand model with complexities,multiple signals needed to synchronize integer period sampling,a rotating mechanism eccentricity measuring method was proposed,and the physical model of rotor-hexagonal sensor-sensor system was set up.theoretical model of eccentricity measurement was established,and the eccentric measurement method was realized in the LabVIEW platform.Aircraft flap actuator input drive system was as the test object,measured eccentric parameters under three kinds of constant speeds,and the measurement errors of the eccentricity are as 2.3%,3.5%,2.2% respectively.The accuracy of the model and the method was verified.
    Fault Diagnosis of Planetary Gearboxes Based on NLSTFT Order Tracking under Variable Speed Conditions
    WANG Youren;WANG Jun;HUANG Haian
    2018, 29(14):  1688-1695. 
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    Aiming at the problems that vibration signal frequencies of planetary gearboxs were fuzzy and interfered by strong noises under variable speed conditions,a fault diagnosis method was proposed based on NLSTFT non-bonding phase order tracking and variational modal decomposition. Firstly,NLSTFT was used to precisely estimate instantaneous frequency of vibration signals,and then transformed into the instantaneous phase curves through integral operation. A smooth angular domain signal was obtained by signal resampling. Secondly,NCOGS(non-convex overlapping group shrinkage) algorithm was used to de-noise the angular domain signals,and VMD(variational mode decomposition) algorithm was used to perform modal decomposition of the angular domain signals. Finally,the fault diagnosis was realized through the demodulation analysis of the envelope spectrum of each modal component signal. The experimental results show that the new method may effectively promote the performances of fault diagnosis under variable speed conditions,which has the high computational efficiency and strong noise robustness.
    Convergence Criteria for Springback Iterative Compensation in Plane Deformation and Its Application
    MA Rui1,2;WANG Chunge3;ZHAO Jun 1,2;ZHAI Ruixue 1,2
    2018, 29(14):  1696-1703. 
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    Based on the iterative method,the iterative compensation mechanism was established and the criterion of the convergence for the iterative parameters was put forward for the springback problem in the plane deformation process of sheet metal. Moreover,it was proved that the axial length has convergence to the iterative compensation mechanism for the elastic-plastic deformation process of uniaxial tension and biaxial stretching in simple stress state. For the V-shape free bending of wide sheet metal,the convergence of the curvature and the bending angle was verified by theory and experiment. Furthermore,the iterative compensation mechanism was applied to the springback control of the free bending of the wide plate,and corresponding experiments were carried out. The results show that,the iterative compensation mechanism can predict the next compensation value based on the springback value of each test,so that the target bending angle with the error of less than 0.1% and the target curvature with the error of less than 0.5% are obtained after 2~3 iterations. Moreover,for the same forming process of same material,each compensation amount depends only on the iteration parameter difference before and after springback.
    Effects of Textured Shaft with Rectangle-shaped Micro-spiral Grooves on Lip Seal Performance
    JIANG Huasheng1;MENG Xiangkai2;PENG Xudong2;LI Weirong3
    2018, 29(14):  1704-1710. 
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    A new type of shaft surface textured with rectangle-shaped micro-spiral grooves was introduced based on the lip seal reverse pumping mechanism to improve the sealing performance,and a steady-state full film lubrication model of lip seals was developed based on the mass conservation cavitation boundary condition,with considering the lip surface roughness and rubber-like elastic deformations.The lubrication governing equation was solved by the finite element method,and the lip seal pumping rate and frictional torque were obtained,then the effects of micro-spiral groove geometry parameters and the shaft rotating speeds on the sealing performances were investigated.The numerical results show that the pumping rate initially increases then decreases slowly with the groove angles,and the optimal groove angle is approximately 25 degree,increases with the groove depth,groove numbers and shaft rotating speed.In the other hand,the frictional torque decreases with the groove angle and groove depth,while increases with the groove numbers,and initially increases then decreases slowly even to arrive at a steady-level with the shaft rotating speed.The results provide a reference for the design and applications of micro-spiral grooves textured on the shaft surfaces improving the lip seal performances.
    Review on Rolling Bearing Axial Preloaded Technique of Motorized Spindles
    LIU Zhifeng1;SUN Haiming1,2
    2018, 29(14):  1711-1723,1763. 
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    Firstly, this paper gave an overview of the application status of the angular contact ball bearings in motorized spindles and analysed the interrelationship between the preloading forces and the performance such as precision, spindle speed, service life of motorized spindles. Second, were the principles and characteristics of the bearing positioning preloading technology and the constant pressure preloading technology reviewed. Then the adjusting preload technology and the automatic preload technology were commented with different preloading methods respectively, such as hydraulic preload equipment, shape memory alloy(SMA) spring, double metal sleeve, piezoelectric equipment, electromagnetic force equipment and centrifugal force equipment etc.. Finally, the future development trends of motorized spindle preloading technology was prospected.
    Adaptive Iterative Learning Control of Trajectory Tracking of SCARA Robots
    ZHANG Tie1;LI Changda1;QIN Binbin1;LIU Xiaogang2
    2018, 29(14):  1724-1729. 
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    In order to reduce the end position errors of robots performing repetitive motion tasks,an adaptive iterative learning control algorithm of trajectory tracking was proposed.The dynamics model of SCARA robot was obtained through Lagrange equation,and the iterative algorithm of control torque was designed.The stability of the algorithm was proved by Lyapunov function.An experimental platform of SCARA robot with typical mechanical structure was built.The experimental results show that the adaptive iterative learning control algorithm effectively reduce the end position errors of the SCARA robot to 1.61% of the original one with strong performability.
    Self-organizing Precision Mode of Heavy-duty Manipulators Based on Waterfall Mechanism
    MA Xiangyu1;LUO Tianhong2
    2018, 29(14):  1730-1735. 
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    In view of the influences of joint errors in manipulator motions on terminal accuracy of heavy-duty manipulators,a self-organizing precision mode of heavy-duty manipulators was put forward based on waterfall mechanism,inspired by the characteristics of automatic restoration of biological waterfall mechanism.Then,the inertia matrix of the manipulator joints was studied and the influences of the joint inertia matrix on end precision were analyzed.Combined with working principles of waterfall mechanism,self-organizing model for heavy-duty manipulator motions was solved.From manipulator inertia forces,the mathematical model of the manipulator joint torques was resolved.Then the simulations show that the self organizing pattern of waterfall mechanism may reduce the effects of joint errors on the accuracy of manipulator joints.
    Gesture Recognition Based on Modified Adaptive Orthogonal Matching Pursuit Algorithm
    LI Bei1;SUN Ying1,2;LI Gongfa1,2,3;JIANG Guozhang1,2,5;KONG Jianyi1,2;JIANG Du1,4;CHEN Disi1,3
    2018, 29(14):  1736-1742. 
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    A modified adaptive orthogonal matching pursuit(MAOMP) algorithm was proposed to guarantee advantages in sparsity estimation and overcome the disadvantages of increasing fixed step values in sparse solution.The algorithm introduced sparsity and variable step sizes.Initial value of sparsity was estimated by matching tests,and the numbers of subsequent iterations were decreased.Finally,the step sizes were adjusted to select atoms and approximate the true sparsity at different stages.Experimental results show that compared with other greedy algorithms,the proposed algorithm improves the recognition accuracy and efficiency.
    Solving Bi-objective FJSP Using Limited Stable Matching Strategy
    YANG Yu;HUANG Min;WANG Zhenyu;ZHU Qibing
    2018, 29(14):  1743-1750. 
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    In practical productions,scheduling with bi-objective including minimum target completion time and minimum production costs was the most common problems in flexible production workshops.An optimization method with limited stable matching strategy was introduced herein to solve FJSP with the bi-objective.The method decomposed a bi-objective optimization problem into a set of scalar optimization subproblems and optimized them using multi-objective evolutionary algorithm.Meanwhile,the limited stable matching strategy was used for coordinating the solutions of subproblems in the  evolution processes to ensure the convergence and diversity of the solutions.The simulation data and application examples demonstrat that the proposed method may obtain the scheduling scheme with the better convergence and diversity to meet the different preferences of decision makers.
    Improvement and Optimization of Hybrid Workshop Layouts Based on Dynamic Differential Cellular Multi-objective Genetic Algorithm
    WANG Yaliang;QIAN Qijing;CAO Haitao;JIN Shousong
    2018, 29(14):  1751-1752. 
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    A new workshop layout optimization problem was proposed,which aimed at a type of hybrid manufacturing mode that was made of discrete operation units,line production units,and special operation units.Multi-objective optimization model for workshop layouts was set up under constraints with goals of the lowest costs of material handling and unit moving,the minimum envelope rectangular area of operation units,and the maximum non-logistics relationship.On the basis of differential cellular multi-objective genetic algorithm,a dynamic differential cellular multi-objective genetic algorithm was proposed to solve this model,through designing and introducing dynamic mutation strategy to improve the global search ability of the algorithm.Feasibility and effectiveness of the model and algorithm were verified by calculation examples and analysis results.