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Research Square 2020年

作者： Dong, Guo-Jiang Du, Fei Wei, Liu-Wei Han, Jie Hebei Key Laboratory of Special Carrier Equipment Yanshan University Hebei Qinhuangdao066044 China Key Laboratory of Advanced Forging Forming Technology Science Ministry of Education Hebei Qinhuangdao066044 China

The extrapolation of the whole life load spectrum from the strengthened road load spectrum in the test site is the key factor for the accuracy of the fatigue durability evaluation of automobile components. In this paper, aiming at the limitation of parameter method extrapolation single distribution estimation, the non parametric extrapolation estimation is introduced to describe the comprehensive characteristics of the load spectrum distribution, and the two extrapolation methods are compared parametrically, and the optimal fitting extrapolation spectrum is selected to carry out the fatigue damage analysis of the sub-frame. Based on the real vehicle test in the proving ground strengthened road, the stress spectrum of the dangerous point of the sub-frame is extracted by co-simulation of multi-body dynamics and finite element method. The parametric method and non-parametric method are used to calculate the goodness of fit of stress spectrum, the optimal mean value and amplitude value probability density of stress spectrum are selected according to the goodness of fit, and the stress spectrum cycle was extrapolated to 106 times, and then the stress spectrum was divided into eight levels. According to Miner criterion, Haibach and NASA S-N curve correction models considering small load damage were respectively used to estimate fatigue damage of front sub-frame. The results show that the fitting effect of non-parametric extrapolation is better than that of parametric extrapolation, and the goodness of fit of equivalent amplitude is 98.6%, which improves the description accuracy of stress spectrum distribution characteristics and provides more accurate extrapolation spectrum for fatigue durability evaluation of components. Based on the extrapolated spectrum and using Haibach model and NASA model to study the fatigue damage of sub-frame, it is shown that NASA model is more suitable for reliability design of components, while Haibach model is suitable for lightweight design

关键词： NASA

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Positioning control of a one-DOF manipulator driven by pneumatic artificial muscles based on active disturbance rejection control

Positioning control of a one-DOF manipulator driven by pneum...

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第三十四届中国控制会议

作者： Ling Zhao Qi Li Hongjiu Yang Hongbo Li 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 College of Mechanical EngineeringYanshan University College of Mechanical Engineering Yanshan University Institute of Electrical Engineering Yanshan University Department of Computer Science and Technology Tsinghua University

The purpose of this paper is to study positioning control performance of the one-DOF manipulator driven by pneumatic artificial muscles using active disturbance rejection controller. Owing to the pneumatic artificial muscle's highly nonlinear and time-varying behavior, it is difficult to achieve good positioning performance. In this paper, the nonlinear and time-varying behavior of pneumatic artificial muscle is considered as disturbance to be estimated by extended state observer. Tracking differentiator is designed to get corresponding smooth signal and differential signal of reference input to avoid overshoot. A linear error feedback combining with estimated value compensation of disturbance is designed to ensure a good response of system. Moreover, stability analysis of the close-loop system is given by Lyapunov theory. Finally, simulation results verify the effectiveness of the proposed controller.

关键词： Active disturbance rejection control,positioning control,pneumatic artificial muscle,disturbance estimation

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A modified nls-dy conjugate gradient method

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ICIC Express Letters 2016年第12期10卷 2921-2925页

作者： Shan, Rui Qi, Changxia Zhao, Jingyi Xu, Yumin School of Science Yanshan University No. 438 Hebei Ave. Qinhuangdao066004 China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University No. 438 Hebei Ave. Qinhuangdao066004 China Key Laboratory of Advanced Forging and Stamping Technology and Science Yanshan University No. 438 Hebei Ave. Qinhuangdao066004 China

This paper proposes a modified NLS-DY conjugate gradient method with disturbance parameters. And under the strong Wolfe line search, the sufficient descent condition and the global convergence are established. At last, the results of numerical experiments demonstrate the effectiveness of the presented algorithm. © 2016 ICIC International.

关键词： Conjugate gradient method

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From the Yoshimura Origami Pattern to Foldable Structures: Optimizing Crease Design for Scalability

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SSRN 2023年

作者： Xu, Dongyang Zhao, Yanzhi Han, Zhen Song, Linquan Key Laboratory of Parallel Robots and Mechatronic Systems Yanshan University Hebei066104 China Key Laboratory of Advanced Forging Technology and Science Ministry of Education Yanshan University Hebei066104 China

Crease design is crucial to the function and application scope of origami projects, yet for the Yoshimura origami pattern, the connection between origami two-dimensional (2D) creases and three-dimensional (3D) forms has not been established, which greatly limits the research and application of origami structures. In this paper, a crease design theory based on the Yoshimura origami pattern is proposed to create 3D foldable origami structures. Afterwards, the flat origami folding process is described, and the corresponding end trajectory equations are derived from the crease chain folding analysis performed on the element block and the expansion block. Next, the positional and angular constraint equations for single-variable, double-variable, and triple-variable foldable forms with only element blocks are systematically discussed. Finally, a detailed folding simulation analysis is performed based on the positional and angular constraint equations, and the foldable form family diagrams with the corresponding angular eigenvalue intersection curve constraints are summarized. This work provides an effective theory for the design of origami creases and provides extensive guidance for the study of Yoshimura-based tubular origami engineering structures. © 2023, The Authors. All rights reserved.

关键词： Eigenvalues and eigenfunctions

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Type Synthesis of 3-Translational Redundant Actuated Parallel Mechanisms With Closed-Loop Branch Chains Based On Graphical Approach

Research Square

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Research Square 2021年

作者： Li, Yong-Quan Jiang, Hong-Sheng Zheng, Tian-Yu Xi, Ke-Long Jing, Han Zhang, Li-Jie Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao066004 China Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education of China Yanshan University Qinhuangdao066004 China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Qinhuangdao066004 China

The 3-translational parallel mechanism is widely used in industrial, medical, and military fields, among others. With the development of the national logistics industry, a pressing need for a kind of 3-translational parallel mechanism emerged. Such mechanisms have high stiffness and high bearing capacity and are used for cargo handling and sorting. A novel method based on the graphical approach was proposed for the synthesis of 3-translational redundancy actuated parallel mechanism with closed-loop branch chains. The new mechanism has four symmetrically arranged branch chains, which eases subsequent kinematics and dynamics analyses while providing good mechanical properties. Based on the graphical approach theory, according to the constraint number contained in the branch chain, two types of redundant driven branch chains with closed-loop structures were constructed. The first type includes rotation constraint in one direction, while the second type includes the rotation constraint in two directions. Based on various combinations of two branch chain types, their allocation schemes can be divided into two types. Moreover, said these two allocation schemes can be integrated into at least 500 and 400 types of 3-translational redundant actuated parallel mechanisms with closed-loop branch chains. Then, the degree of freedom properties of representative mechanisms were tested using the screw theory. A large number of novel mechanisms were integrated assessed using this method, and branch chains such mechanisms were symmetrically distributed. They have a strong bearing capacity, simple calculation, and control, and can be applied to the handling and sorting of goods, large-scale precision machine tools, and large construction machinery vibration isolation systems, among others. © 2021, CC BY.

关键词： Redundancy

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Effect of Process Parameters on the Formability, Microstructure and Mechanical Properties of Laser-Arc Hybrid Welding of Q355b Steel

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SSRN 2022年

作者： Bi, Jiang Zhang, Liping Peng, Genchen Yuan, Xiaoming Li, Wen Zhang, Lijie Hebei Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Qinhuangdao066004 China Jiangsu XCMG Construction Machinery Research Institution Ltd. Xuzhou221000 China Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education of China Yanshan University Qinhuangdao066004 China

Thick plate steel structure is widely used in construction machinery, pressure vessels, ships and other manufacturing fields. To obtain an acceptable welding quality and efficiency, the thick plate steel is always joined by laser-arc hybrid welding technology. In this paper, the Q355B steel with the thickness of 20 mm was taken as the research object, and the process of narrow groove laser-arc hybrid welding was studied. The results showed that the laser-arc hybrid welding method could realize one backing and two filling welding with the single groove angles of 8-12°. At different plate gaps of 0.5 mm, 1.0 mm and 1.5 mm, and the shape of weld seams were satisfied with no undercut, blowhole or other defects. The average tensile strength of welded joints was 486~493 MPa, and the fracture position was in the base metal area. Due to the high cooling rate, a large amount of lath martensite formed in heat affected zone (HAZ) and this zone exhibited higher hardness values. The impact roughness of the welded joint was almost 66-74 J with different groove angles. © 2022, The Authors. All rights reserved.

关键词： Microstructure

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The stability performances improvement through kinematic and dynamic modeling of the hopping robots

The stability performances improvement through kinematic and...

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UKACC International Conference on Control (CONTROL)

作者： Adrian Bruja Luige Vladareanu Gal Ionel Alexandru Hongbo Wang Hongnian Yu Jingjing Liu Institute of Solid Mechanics of Romanian Academy (IMSAR) Bucharest Romania School of Design Engineering and Computing Boumemouth University Poole Dorset UK Parallel Robot and Mechatronic System Laboratory of Hebei Province Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Qinhuangdao China

The paper presents an innovative design for a wheeled hopping robot. Our main objective was to obtain a stable and efficient robot, which can jump over obstacles and has the ability to reach a certain ledge. The innovative design of our robot has the capability to jump to a certain distance even with a zero initial velocity provided by the wheels movement. Also, we took into consideration the wind speed which can prevent our robot to reach the desired destination, and compensated with an initial velocity on the direction of movement. For testing we designed a simulation which had as inputs different initial conditions to test and present the jumping capability of our robot in different jumping conditions. In the end we provide a jump area which the robot can reach for certain initial conditions, so we can later chose the optimal one for reaching the target position.

关键词： Mobile robots Springs Wheels Trajectory Collision avoidance Shafts

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Isotropic Analysis of Line Vector Forces and Its Application in Type Synthesis of Mechanisms

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Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery 2019年第1期50卷 406-411页

作者： Xu, Yundou Guo, Jinwei Wang, Zhifeng Chen, Yang Yao, Jiantao Zhao, Yongsheng Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao066004 China Key Laboratory of Advanced Forgingand Stamping Technology and Science Ministry of Education Yanshan University Qinhuangdao066004 China Capital Aerospace Machinery Co. Ltd. Beijing100076 China

The carrying capacity of a mechanism is closely related to its line vector force. A thorough isotropic analysis of line vector forces was presented. The results showed that the isotropic condition can be satisfied when the line vector forces were evenly distributed on a conical surface with a cone-top angle of 109.472°. In addition, since few three degrees-of-freedom (DOFs) translational redundantly actuated parallel manipulators were reported, by combining the isotropic line vector forces, a method for the type synthesis of 3-DOF, redundantly actuated translational parallel mechanisms (PMs) was proposed, in which the arrangement of the active joints was taken into account in advance. Using this method, firstly a kinematic chain with a twist system reciprocal to both the constraint and actuation wrenches was constructed, and then the active joint reciprocal to the constraint wrenches but not to the actuation wrench was constructed. Thus, a series of typical redundantly actuated PMs with isotropic actuation forces were obtained. Finally, the 4-PRRR PM was analyzed as an example, and the results showed that the isotropy of the load-carrying capacity can always be satisfied during its movement, because the condition of force Jacobian matrix was always equal to one, which to some extent verified the correctness of the isotropic analysis and the synthesis method proposed in this research. For this method, it not only satisfied the expected requirements, but also meant that the active joints no longer needed to be selected, and the rationality of the selection did not need to be considered, which provided a new method for the type synthesis of parallel manipulators. © 2019, Chinese Society of Agricultural Machinery. All right reserved.

关键词： Vectors

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Microstructure, Mechanical Properties and Multiphase Synergistic Strengthening Mechanisms of an Al14znmgzr Alloy Printed by Laser Powder Bed Fusion

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SSRN 2024年

作者： Bi, Jiang Wang, Keqi Wu, Chen Chi, Jinze Liu, Bokun Zhang, Liping Chen, Xi Lu, Nannan Starostenkov, Mikhail Dmitrievich Dong, Guojiang Qin, Xikun Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education Yanshan University Qinhuangdao066004 China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin150001 China Institute of Metal Research Chinese Academy of Sciences Shenyang110016 China General Physics Department Altai State Technical University Leninst. 46 Barnaul656099 Russia

In this work, a novel aluminum alloy with high Zn content was designed for laser powder bed fusion (LPBF) forming process. Aluminum alloy powder containing 14 wt.% Zn and 2 wt.% Zr was produced to conduct LPBF experiments with different process parameters. The analysis of the specimens revealed that the up facing surface exhibited an average microhardness peak value of 170.6 HV, achieving the ultimate tensile strength (UTS) of 573 MPa and the elongation of 11.6%. There was no significant change in grain size and a large amount of plate-like η' phase precipitated within the grains after aging treatment (120°C, 21h). The specimen reached the average microhardness peak of 181.7 HV and the UTS of 605 MPa. The principal strengthening mechanisms in the LPBF-formed samples were solid solution strengthening and grain refinement strengthening. After aging treatment, the precipitation of the second phase from solute atoms led to grain refinement strengthening and second-phase strengthening becoming the predominant factors to enhance the sample's strength. Al14ZnMgZr alloy have great application prospect in high strength and tough service environment. © 2024, The Authors. All rights reserved.

关键词： Aluminum alloys

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Forced responses of field modulated magnetic gear system

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ICIC Express Letters 2014年第7期8卷 2025-2030页

作者： Yuan, Xiaoming Zhang, Lijie Du, Bing Hao, Xiuhong Key Laboratory of Advanced Forging and Stamping Technology and Science Ministry of Education of China Yanshan University No. 438 Hebei Ave. Qinhuangdao 066004 China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University No. 438 Hebei Ave. Qinhuangdao 066004 China School of Mechanical Engineering Yanshan University No. 438 Hebei Ave. Qinhuangdao 066004 China

Considering the torque ripples on the rotors, the dynamic model and the dynamic differential equations of field modulated magnetic gear (FMMG) system are founded. When the excitation frequency is close to a certain natural frequency of FMMG system, the expressions of the forced responses are deduced and the laws of the resonance responses are discussed. Results show that the amplitude of only a certain degree of freedom is always much bigger than others, because the electromagnetic coupling stiffnesses are weaker than the supporting stiffnesses. Forced responses of FMMG system can provide the theoretical basis for the parameter optimization during designing. © 2014 ISSN 1881-803X.

关键词： Dynamic models

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