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Frictional characteristics of sheet metals with superimposed ultrasonic vibrations

Journal of Central South University 2018年第8期25卷 1879-1887页

作者： CAO Miao-yan LI Jian-chao LIU Yan-yang YUAN Ya-ning ZHAO Chang-cai DONG Guo-jiang National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004China Chinese Academy of Agricultural Mechanization Sciences Beijing 100083China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education of China Yanshan UniversityQinhuangdao 066004China College of Vehicles and Energy Yanshan UniversityQinhuangdao 066004China

The forming performance of sheet metals in the deep-drawing process with ultrasonic vibrations can be improved by the surface effect between the sheet metal and the die.A sheet metal friction test with ultrasonic vibrations is performed to explore the cause of the surface *** frictional characteristics are investigated,and the corresponding friction expressions are established based on the contact mechanics and the elastic–plastic contact model for rough *** is caused by the elastic–plastic deformation of contacting asperities under normal *** actual contacting region between two surfaces increases with normal loads,whereas the normal distance *** normal distance between the contacting surfaces is changed,asperities generate a tangential deformation with ultrasonic vibrations,and the friction coefficient is eventually *** vibrations are applied on a 40Cr steel punch at the frequency of 20 kHz and the amplitude of 4.2μ*** the friction tests,the punch is perpendicular to the surface of the magnesium alloy AZ31B sheet metals and is sliding with a relative velocity of 1 mm/*** test results show that the friction coefficient is decreased by approximately 40%and the theoretical values are in accordance with the test values;Ultrasonic vibrations can clearly reduce wear and improve the surface quality of parts.

关键词： friction ultrasonic vibrations sheet metals contact model

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The energy saving factor research of secondary regulation system of cement coating machine

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ICIC Express Letters, Part B: Applications 2015年第11期6卷 3077-3084页

作者： Kong, Xiangdong Luo, Hongliang Ai, Chao He, Long Dong, Yanwu Key Laboratory of Advanced Forging and Stamping Technology and Science Ministry of Education of China No. 438 Hebei Avenue Qinhuangdao China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University No. 438 Hebei Avenue Qinhuangdao China

The cement coating machine is widely used, but it wastes a lot of energy when braking. In order to overcome the weakness, secondary regulation system is put forward to recycle energy. Firstly the secondary regulation speed control system is proposed. Then the mathematical model of hydraulic secondary regulation system is established, and efficiency calculation method is derived. At last, through the simulation analysis and experimental verification, the feasibility of energy saving project is proved. With bigger slope and lower hydraulic pressure, the system can recycle more energy. © 2015 ICIC International.

关键词： Energy conservation

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Output Feedback Control of Hydraulic Driven Flexible Actuator with Imprecise Modeling

Output Feedback Control of Hydraulic Driven Flexible Actuato...

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第43届中国控制会议

作者： Huidong Hou Jinsong Zhao Yi Liu Xianwei Niu Yunpeng Zhang School of Mechanical Engineering Yanshan University State Key Laboratory of Crane Technology Yanshan University Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Key Laboratory of Advanced Forging and Stamping Technology and Science Ministry of Education

ISBN: (数字)9789887581581

ISBN: (纸本)9798350366907

In recent years,flexible soft robots have received increasing attention compared to rigid robots. The modeling of flexible actuators has always been difficult to solve. The control problem of hydraulic driven flexible actuators in this paper under the premise of imprecise modeling. In this paper,an innovative output feedback controller based on Unknown System Dynamics Estimator(USDE) is proposed to improve the position tracking accuracy of hydraulic driven flexible actuators with imprecise model. Firstly,the strict feedback high order electro-hydraulic servo system is transformed into a new standard form that incorporates servo valve dynamics. Therefore,controllers designed using traditional backstepping methods are rendered obsolete. Subsequently,a High-Gain Observer(HGO) is introduced for state reconstruction of the new system. To counteract the impact of lumped unknown system dynamics which include imprecise modeling dynamics of hydraulic driven flexible actuator,a USDE with straightforward parameter tuning and robust performance is introduced. Finally,both scalar containing error terms and USDE are integrated into the design of the output feedback controller. Experimental validation is conducted to demonstrate the effectiveness of the proposed method.

关键词： Electro-hydraulic servo system Flexible actuator Imprecise model estimation Output feedback control

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Reliability Prediction Method of Hydraulic System by Fuzzy Theory

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IFAC Proceedings Volumes 2013年第5期46卷 457-462页

作者： Dongning Chen Chengyu Yao Zhongkui Feng Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Qinhuangdao China (Tel: ***) Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) Ministry of Education of China Qinhuangdao China Key Laboratory of Industrial Computer Control Engineering of Hebei Province Yanshan University Qinhuangdao China

The hydraulic system's reliability is a key factor to ensure the reliable operation of equipment and it is very important to evaluate reliability of hydraulic system. The paper describes a reliability prediction method that may be used to evaluate the reliability of hydraulic systems for industrial applications. The proposed method takes advantage of fuzzy set theory. The aim of this method is to minimize the deficiencies of the traditional reliability prediction methods treating a failure rate as fixed value due to insufficiency practice data. Triangular fuzzy number and Gaussian fuzzy number are used in the application of this prediction method, where environmental factor, derating factor, and other factors are considered. Finally, an example of type crane's hydraulic system is given to verify the feasibility and practicability of the method.

关键词： Type crane Hydraulic system Reliability prediction Fuzzy theory Reliability logic diagram

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Reliability Optimization of Multi-state Hydraulic System Based on T-S Fault Tree and Extended PSO Algorithm

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IFAC Proceedings Volumes 2013年第5期46卷 463-468页

作者： Chengyu Yao Bin Wang Dongning Chen Key Laboratory of Industrial Computer Control Engineering of Hebei Province Yanshan University Qinhuangdao China (Tel: ***) Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Qinhuangdao China Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) Ministry of Education of China Qinhuangdao China

In order to overcome the difficulty of constructing the multi-state system's reliability optimization model, and the shortage of premature convergence of PSO (Particle Swarm Optimization) algorithm, a new reliability optimization method based on T-S fault tree and EPSO (Extended PSO) algorithm is proposed. According to the T-S fault tree and T-S rules of the events, the multi-state system reliability optimization model is constructed, at the same time, given constraint conditions on the system cost, weight and volume, and combined with the death penalty to construct the fitness function. Furthermore, EPSO algorithm based on the attraction and repulsion forces in the artificial physics is applied to the reliability optimization of multi-state hydraulic system. Comparing with PSO algorithm, the results of EPSO algorithm are in a better performance in obtaining global optimal solution.

关键词： Hydraulic system Reliability optimization Multi-state T-S fault tree EPSO algorithm

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Simulation and Experimental Research of Digital Valve Control Servo System Based on CMAC-PID Control Method

Simulation and Experimental Research of Digital Valve Contro...

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第六届工程机械与车辆工程新进展国际学术会议

作者： ZHAO Jin-song ZHAO Zi-ning WANG Zhi-peng ZHANG Chuan-bi YAO Jing Hebei Province Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science(Yanshan University) Ministry of Education of China School of Mechanical Engineering Yanshan University

Digital valve control servo system is studied in this *** order to solve the system problems of poor control precision and slow response time,this paper proposes a CMAC-PID(Cerebellar model artic

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Fault diagnosis method for hydraulic pump based on order tracking

Fault diagnosis method for hydraulic pump based on order tra...

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International Conference on Fluid Power and Mechatronics (FPM)

作者： Wanlu Jiang Yong Zhu Meng Wang Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Qinhuangdao China Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) Ministry of Education of China Qinhuangdao China

ISBN: (纸本)9781479987719

Aiming at the problem of extracting fault features from hydraulic pump under variable rotating speed, a fault diagnosis method based on order tracking was proposed. Firstly, the original signal was decomposed by ensemble empirical mode decomposition into a series of intrinsic mode function (IMF) components. Afterwards, the fault sensitive IMF was selected by combining energy spectrum and spectral kurtosis. Secondly, the selected IMF was processed by Hilbert demodulation and down-sampling. Moreover, an appropriate frequency band was chosen and the signal was further processed by wavelet cluster-based bandpass filtering. Then, the fault sensitive envelope signal was obtained. Thirdly, the instantaneous frequency was extracted from the envelop signal by wavelet ridge tracking, and the time instant of phase discrimination was further calculated. Moreover, the even angle spaced resample was performed to the envelope signal. Then, the time domain non-stationary signal was transformed to the angular domain stationary signal. Finally, the stationary signal was analyzed by order tracking, and the fault diagnosis was executed according to the order spectrum. Furthermore, an application was performed to the vibration signals of hydraulic pump under variable rotating speed. The signals were respectively acquired in four typical states, which were normal, loose slipper, slipper wear and swash plate wear. Results indicate that the proposed method can effectively extract the fault features of hydraulic pump and further realize fault diagnosis.

关键词： Vibrations Fault diagnosis Feature extraction Time-domain analysis Pumps Valves Demodulation

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Axial piston pump mechanical vibration transmission path and the rear shell sensitivity analysis

Axial piston pump mechanical vibration transmission path and...

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IEEE International Conference on Aircraft Utility Systems

作者： Lingxiao QUAN Qiwei ZHANG Zongxia JIAO Jianwei LIU Song Liu Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control and Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) Ministry of Education of China Yanshan University School of Mechanical Engineering Yanshan University

ISBN: (纸本)9781509010882

The mechanical vibration transfer path model of the axial piston pump was established for aiming at the aviation hydraulic vibration that it has been more intense with the development trend of high speed and high pressure. In this paper, firstly, based on the first-order trajectory sensitivity method to solve the time-domain sensitivity function curves, the system parameters that have influence on the vibration response of the pump were determined. Secondly, two sensitivity measure indexes were defined to quantitative analysis of the effect that various parameters on the rear shell vibration displacement. We hope that the work in this paper can have some benefit for controlling the aircraft hydraulic system machinery vibration coming from the pump, optimizing the structure of aviation hydraulic pump and promoting the development of domestic large aircraft, providing theoretical and technical basis.

关键词： Transmission Path axial piston pump Mechanical Vibration system parameter Pumps aviation High speed hydraulic oscillation

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Dynamics Parameter Identification and Control of a Spherical 2-DOF Redundant Driven Parallel Robot System

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Zhongguo Jixie Gongcheng/China Mechanical Engineering 2019年第16期30卷 1967-1975页

作者： Li, Yongquan Wu, Pengtao Zhang, Yang Zhang, Lijie Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University QinhuangdaoHebei066004 China Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education Yanshan University QinhuangdaoHebei066004 China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University QinhuangdaoHebei066004 China

A spherical 2-DOF redundant drive parallel robot driven by servo motor was the research ***, the inertia parameter identification model of the mechanisms was established, and the inertial parameter identification trajectory was ***, the friction parameter identification model of the mechanism pairs and the friction parameter identification model of the driving system were established, and their identification principles were analyzed *** trajectory of friction parameter identification was also ***, through the identification experiments, the mechanism inertia parameters, the mechanism rotation pair friction parameters and the driving system friction parameter identification results were obtained, the original mechanism parameters were modified by the identification results, a more accurate robot system dynamics model was obtained, and the identification results were validated by the trajectory test ***, a feed forward control strategy was developed based on the dynamics model of the robot system and compared with the traditional mechanism kinematics closed-loop control *** feasibility of this control strategy was proved. © 2019, China Mechanical Engineering Magazine Office. All right reserved.

关键词： Mechanisms

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Environmental Stress Analysis of the Aviation Hydraulic Pipeline Effected by the Hydraulic Pressure

Environmental Stress Analysis of the Aviation Hydraulic Pipe...

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2016 IEEE/CSAA International Conference on Aircraft Utility Systems(AUS)

作者： Lingxiao Quan Xu Ding Junqiang Shi Hui Yu Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control and Key Laboratory of Advanced Forging & Stamping Technology and Science(Yanshan University) Ministry of Education of ChinaYanshan University School of Mechanical Engineering Yanshan University

China’s first self-developed aircraft C919 has been assembly *** in the ability to analyze the environmental stress of aviation pipeline will result in less reliability and higher failure rate of aircraft hydraulic system under variable environment *** we have selected a straight pipeline and a bend one of the wing position,and whose environmental stress were analyzed on ABAQUS ***,the article gave the three-dimensional model and provided the relevant *** mathematical model of straight pipeline and bend pipeline were established with the transfer matrix *** but not the least,we have completed straight pipeline stress distribution analysis under different shock pressures and static pressure,analysis of bend pipeline modal and vibration *** results will support guidelines for research of aviation hydraulic pipeline stress,which also will be significant for the next step with optimal design of aircraft hydraulic pipeline.

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