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Newton chaos iteration method and its application to mechanism kinematics synthesis 被引量:6
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作者 罗佑新 郭惠昕 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期13-17,共5页
Many questions in natural science and engineering can be transformed into nonlinear equations. Newton iteration method is an important technique to one dimensional and multidimensional variables and iteration itself i... Many questions in natural science and engineering can be transformed into nonlinear equations. Newton iteration method is an important technique to one dimensional and multidimensional variables and iteration itself is very sensitive to initial guess point. This sensitive area is the Julia set of nonlinear discrete dynamic system which Newton iteration method forms. The Julia set, which is the boundaries of basins of attractions, displays the intricate fractal structures and chaos phenomena. By constructing repulsion two-cycle point function and making use of inverse image iteration method, a method to find Julia set point was introduced. For the first time, a new method to find all solutions was proposed based on utilizing sensitive fractal areas to locate the Julia set points to find all solutions of the nonlinear questions. The developed technique used an important feature of fractals to preserve shape of basins of attraction on infinitely small scales. The numerical examples in linkage synthesis showed that the method was effective and correct. 展开更多
关键词 CHAOS FRACTAL Julia set link mechanism nonlinear equations
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Large Deformation Analysis and Synthesis of Elastic Closed-loop Mechanism Made of a Certain Spring Wire Described by Free Curves 被引量:1
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作者 IWATSUKI Nobuyuki KOSAKI Takashi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期756-762,共7页
Recently novel mechanisms with compact size and without many mechanical elements such as bearing are strongly required for medical devices such as surgical operation devices. This paper describes analysis and synthesi... Recently novel mechanisms with compact size and without many mechanical elements such as bearing are strongly required for medical devices such as surgical operation devices. This paper describes analysis and synthesis of elastic link mechanisms of a single spring beam which can be manufactured by NC coiling machines. These mechanisms are expected as disposable micro forceps. Smooth Curvature Model(SCM) with 3rd order Legendre polynomial curvature functions is applied to calculate large deformation of a curved cantilever beam by taking account of the balance between external and internal elastic forces and moments. SCM is then extended to analyze large deformation of a closed-loop curved elastic beam which is composed of multiple free curved beams. A closed-loop elastic link is divided into two free curved cantilever beams each of which is assumed as serially connected free curved cantilever beams described with SCM. The sets of coefficients of Legendre polynomials of SCM in all free curved cantilever beams are determined by taking account of the force and moment balance at connecting point where external input force is applied. The sets of coefficients of Legendre polynomials of a nonleaded closed-loop elastic link are optimized to design a link mechanism which can generate specified output motion due to input force applied at the assumed dividing point. For example, two planar micro grippers with a single pulling input force are analyzed and designed. The elastic deformation analyzed with proposed method agrees very well with that calculated with FEM. The designed micro gripper can generate the desired pinching motion. The proposed method can contribute to design compact and simple elastic mechanisms without high calculation costs. 展开更多
关键词 elastic link mechanism CLOSED-LOOP spring beam large deformation analysis smooth curvature model force balance equation synthesi
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Multiple Resonance and Stability of a Motor-elastic Linkage Mechanism System 被引量:1
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作者 李兆军 蔡敢为 戴文正 《Journal of Donghua University(English Edition)》 EI CAS 2006年第4期1-6,共6页
The dynamics of a three-phase AC motor-elastic linkage mechanism system is considered. Taking the drive motor and the linkage mechanism as an integrated system, the coupling dynamic equations of the system are establi... The dynamics of a three-phase AC motor-elastic linkage mechanism system is considered. Taking the drive motor and the linkage mechanism as an integrated system, the coupling dynamic equations of the system are established by the finite element method. The multiple resonance and its stability of the system are studied using the method of multiple scales. The first order approximate solutions of the multiple resonance of the system are obtained. An algorithm for determining the stability of resonance is derived. The studies show that the multiple resonance and its stability of the system are not only related to the structure parameters of the linkage mechanism, but also to the electromagnetism parameters of the motor. At last, an experiment is given to verify the results of the theoretical analysis. 展开更多
关键词 MOTOR link mechanism multiple resonance STABILITY multiple scales method.
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Research and Application for the Regularity of Distribution about Curvature Radius and Curvature Center of the Linkage Point Track in a Link Mechanism 被引量:2
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作者 WANG Yun-di WANG Liang-wen +1 位作者 ZHANG Hang-wei DONG Hai-jun 《International Journal of Plant Engineering and Management》 2012年第3期160-168,共9页
It is illustrated that there exists an inflection circle on the linkage rigid body by the principle of relative motion. Confirmed methods of the inflection circle, curvature radius and curvature center of the point tr... It is illustrated that there exists an inflection circle on the linkage rigid body by the principle of relative motion. Confirmed methods of the inflection circle, curvature radius and curvature center of the point track on the linkage rigid body are given in the case of the different contact type of move instantaneous center line and static instantaneous center line. The regularity of distribution of curvature radius and curvature center of the point track is researched. The identification methods called determination parameters and auxiliary vertical line of the diameter and direction of the inflection circle in the four bar mechanism are pointed out. A design method of the crane hoisting mechanism is discussed in the end of this paper. 展开更多
关键词 link mechanism linkage point track instantaneous center line inflection circle determination parameters and auxiliary vertical line curvature radius curvature center distribution regularity the crane hoisting mechanism
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Determination of the workspace of a new coordinate-measuring machine using parallel-link mechanism
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作者 刘得军 黄庆成 +2 位作者 叶东 车仁生 周琳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第2期147-154,共8页
Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing th... Presents the detailed algorithm established for determination of workspace for a 3-DOF coordinate measuring machine using parallel link mechanism by constructing the inverse kinematic model first and then reviewing the physical and kinematical constraints from the structural characteristics of the parallel link mechanism, and discusses the actual geometries of workspace and the factors having effect on workspace through computer simulation thereby providing necessary theoretical basis for the research and development of coordinate measuring machines using parallel link mechanism. 展开更多
关键词 coordinate measuring machine WORKSPACE parallel link mechanism three degrees of freedom spatial coordinate
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Development of Five-Finger Multi-DoF Myoelectric Hands with a Power Allocation Mechanism
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作者 Tatsuya Seki Tatsuhiro Nakamura Ryu Kato Soichiro Morishita Hiroshi Yokoi 《Journal of Mechanics Engineering and Automation》 2014年第2期97-105,共9页
To be used as five-fingered myoelectric hands in daily living, robotic hands must be lightweight with the size of human hands. In addition, they must possess the DoFs (degrees of freedom) and high grip force similar... To be used as five-fingered myoelectric hands in daily living, robotic hands must be lightweight with the size of human hands. In addition, they must possess the DoFs (degrees of freedom) and high grip force similar to those of human hands. Balancing these requirements involves a trade-off; ideal robotic hands have yet to sufficiently satisfy both requirements. Herein, a power allocation mechanism is proposed to improve the grip force without increasing the size or weight of robotic hands by using redundant DoFs during pinching motions. Additionally, this mechanism is applied to an actual five-fingered myoelectric hand, which produces seven types of motions necessary for activities of daily living and realizes a -60% improvement in fingertip force, allowing three fingers to pinch objects exceeding 1 kg. 展开更多
关键词 Five-finger multi-degree of freedom (DoF) robotic hand power allocation mechanism interference driven link based onwire mechanism.
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On Translation Strategies and Cultural Effects of Chinese Menu in English Version——An Analysis from the Perspective of Reception Theory
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作者 张周瑞 《疯狂英语(理论版)》 2016年第1期158-159,162,共3页
Reception theory stresses reader's activeness.Translation of Chinese Menu in English Version reveals the universal principles of transnational strategies and methods of menu translation.Through analysis of Chinese... Reception theory stresses reader's activeness.Translation of Chinese Menu in English Version reveals the universal principles of transnational strategies and methods of menu translation.Through analysis of Chinese Menu in English Version,the article studies its text and examines the linking mechanism between reception theory and menu translation.A comparative conclusion shows that in menu translation attention is paid to the accuracy of the target text by translators,who are simultaneously aware of the paradox between expectation and acceptance of individual readers. 展开更多
关键词 menu translation linking mechanism reception theory
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KINETO-ELASTODYNAMIC ANALYSIS USED BY THE MATRIX-TRANSIT METHOD
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作者 Tong Zhou Zou HujunShanghai Jiaotong University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第2期149-154,共6页
An element based on the harmonic functions for Performing vibration analysis oflinkages was developed to propose the matrix-transit equations and the kineto-elastrodynamics(KED) different equations. Method and the KED... An element based on the harmonic functions for Performing vibration analysis oflinkages was developed to propose the matrix-transit equations and the kineto-elastrodynamics(KED) different equations. Method and the KED equations was continllous undertaken by themodal superposition approach. The results from those equations include the quasistatic parts andthe dynamic parts. The dynamic parts equaled to the developing parts of the computationaccurations. 展开更多
关键词 Kineto-elastrodynamics (KED) Matrix-transit methods Laser experimentPlaner elastric link mechanism Space elastric link mechanics
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Continuously Variable Transmission Using Quadric Crank Chains and Ratchets
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作者 Toshihiro Yukawa 《Journal of Energy and Power Engineering》 2012年第4期645-655,共11页
This paper describes the CVT (continuously variable transmission). Generally, CVTs are classified as belt-type or toroidal CVTs, and each CVT is basically composed of two parts such as the V-belt and pulley, or fric... This paper describes the CVT (continuously variable transmission). Generally, CVTs are classified as belt-type or toroidal CVTs, and each CVT is basically composed of two parts such as the V-belt and pulley, or friction wheels. In the belt-type CVT, the pulley is driven by a belt placed between two (left and right) circle boards, while in the toroidal CVT, two rollers rotate under the condition being pushed by strong compression power. Since these conventional CVTs use friction force, their energy transfer efficiency might be inferior. Furthermore, although these CVTs require precise structures and processing, they make noise, and are not durable. Consequently, we propose a new structural CVT in this paper. 展开更多
关键词 Continuously variable transmission quadric crank chain link mechanism cam ratchet.
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Approximate Conditional Likelihood for Generalized Linear Models with General Missing Data Mechanism 被引量:7
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作者 ZHAO Jiwei SHAO Jun 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第1期139-153,共15页
The generalized linear model is an indispensable tool for analyzing non-Gaussian response data, with both canonical and non-canonical link functions comprehensively used. When missing values are present, many existing... The generalized linear model is an indispensable tool for analyzing non-Gaussian response data, with both canonical and non-canonical link functions comprehensively used. When missing values are present, many existing methods in the literature heavily depend on an unverifiable assumption of the missing data mechanism, and they fail when the assumption is violated. This paper proposes a missing data mechanism that is as generally applicable as possible, which includes both ignorable and nonignorable missing data cases, as well as both scenarios of missing values in response and covariate.Under this general missing data mechanism, the authors adopt an approximate conditional likelihood method to estimate unknown parameters. The authors rigorously establish the regularity conditions under which the unknown parameters are identifiable under the approximate conditional likelihood approach. For parameters that are identifiable, the authors prove the asymptotic normality of the estimators obtained by maximizing the approximate conditional likelihood. Some simulation studies are conducted to evaluate finite sample performance of the proposed estimators as well as estimators from some existing methods. Finally, the authors present a biomarker analysis in prostate cancer study to illustrate the proposed method. 展开更多
关键词 Asymptotic normality generalized linear model IDENTIFIABILITY missing data mechanism non-canonical link function nonignorable missingness.
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