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66th International Astronautical Congress 2015: Space - The Gateway for Mankind's Future, IAC 2015

作者： Betelin, V.B. Phylippov, Yu.G. Nikitin, V.F. Dushin, V.R. Smirnov, N.N. Koo, Jaye Son, Min Scientific Research Institute for System Analysis Russian Academy of Sciences Moscow117218 Russia Moscow M.V. Lomonosov State University Leninskie Gory 1 Moscow119992 Russia School of Aerospace and Mechanical Engineering Korea Aerospace University Goyang-city411-791 Korea Republic of

ISBN: (纸本)9781510818934

Computer aided design of new effective engines needs mathematical tools for supercomputer modeling of components mixing and combustion in rocket engines. Pulse detonation engines is a new trend in increasing rocket engines effectiveness. The paper presents the results of developing verification and validation of mathematical model making it possible to simulate unsteady processes of ignition and deflagration to detonation transition in novel type of pulse detonation engines. One of peculiarities of hydrogen-oxygen rocket engine is the following. On injecting liquid components fuel (hydrogen) having must lower critical temperature comes pre-evaporated and pre-heated in combustion chamber, while oxygen could be liquid then evaporating inside the chamber. Thus contrary to most types of engines hydrogen engine has an inverse mixture entering combustion chamber, in which fuel is gaseous and oxidant is liquid. Combustion in terrestrial conditions is strongly affected by thermogravitational instability, which provides additional very effective mixing of the components and formation of combustible mixture in the vicinity of each droplet. On the contrary, this mechanism does not work under low gravity conditions. Only diffusion contributes to mixing, which makes ignition and combustion conditions less favorable.

关键词： Oxygen

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An improving analytically model with high accuracy for a micro manipulator

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Journal of Information Hiding and Multimedia Signal Processing 2015年第6期6卷 1242-1249页

作者： Ni, Yuan Deng, Zong-Quan Li, Jun-Bao Wu, Xiang Li, Long Research Center of Aerospace Mechanism and Control School of Mechatronics Engineering Harbin Institute of Technology China Shanghai Key Laboratory of Mechanical Automation and Robotics SSchool of Mechatronic Engineering and Automation Shanghai University China

A proposed mathematical model is established for modal analysis of a micro manipulator. According to the geometric characteristics of the manipulator, the model is built by using finite element method with multipoint constraint equations, and the corresponding displacement coordinate matrix is obtained after that. Considering that the regular flexure hinge plays a key role, in this analysis process, the hinge is treated as a varied cross-section Euler-Bernoulli beam element and the finite element model is established by a new procedure which followed the element internal equilibrium principle consequently. The stiffness matrix, the mass matrix and the exact shape functions of the non-prismatic beam element can be obtained respectively. Furthermore, the influences of geometric parameters on the fundamental frequency can also be discussed. © 2015 Ubiquitous International. All rights reserved.

关键词： Natural frequencies

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Role of the innermost and outermost edge flames on flame extinction in buoyancy-suppressed methane-air non-premixed counter triple co-flow flames 10

Role of the innermost and outermost edge flames on flame ext...

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10th Asia-Pacific Conference on Combustion, ASPACC 2015

作者： Park, J.W. Park, J. Kwon, O.B. Yun, J.H. Keel, S.I. Lee, K.M. Interdisciplinary Program of Biomechanical Engineering Pukyong National University Busan Korea Republic of Dept. of Mechanical Engineering Pukyong National University Busan Korea Republic of Environmental and Energy System Research Division Korea Institute of Machinery and Materials Daejeon Korea Republic of Dept. of Aerospace Engineering Sunchon National University Sunchon Korea Republic of

Important role of the outermost and innermost edge flames on flame extinction was investigated in buoyancy-suppressed non-premixed counter-flow flame with a triple co-flow configuration. The use of He curtain flow produced a microgravity level of 10-2-10-3 g in He-diluted non-premixed counter triple co-flow flame experiments. Flame stability map was presented based on flame extinction and oscillation near extinction limit. The stability map via critical diluent mole fraction with global strain rate was represented by varying outer and inner He-diluted mole fractions. Distinct oscillation regimes existed, and the oscillation and extinction modes were quite different each other in terms of the global strain rate and outer and inner He-diluted mole fractions. The flame extinction modes could be classified into five. The result showed that the edge flame speed was influenced significantly by the conductive heat losses to the inner cold flow mixture or He curtain flow ambience.

关键词： Buoyancy

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Control system of a small intelligent inspection robot for nuclear power plant use

Control system of a small intelligent inspection robot for n...

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International Conference on Information and automation (ICIA)

作者： Erzhen Pan Da Guan Wenfu Xu Bingshan Hu School of Mechanical Engineering and Automation Harbin Institute of Technology Shenzhen China Shenzhen Engineering Lab of Industrial Robot and System Shenzhen China Shanghai Institute of Aerospace Systems Engineering Shanghai Key Laboratory of Spacecraft Mechanism Shanghai China

ISBN: (纸本)9781467391054

Since Fukushima nuclear accident, the international society are paying more and more attention on the safety of nuclear power. The healthy monitoring is the most important means for earth warning. In this paper, we developed the control system for an intelligent monitoring robot used in nuclear power plants. The control system is actually a two-level controller, consisting of the host computer and lower computer. The host computer is a traditional PC, supplying the human-computer interface. It is also used for mission planning, control parameters setting, monitoring results processing and displaying, and so on. The lower computer is an ARM embedded controller. It is directly connected to all actuators and sensors. The real-time operation system uc/os-ii is also migrated to the ARM processor. It effectively manages the hardware resource and the multiple tasks in real time. Typical experiments verified the effectiveness and reliability.

关键词： Temperature sensors Computers Monitoring Sensor systems Robot sensing systems

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A novel dynamic decoupling control algorithm for PMSA by utilizing single neural adaptive controllers

A novel dynamic decoupling control algorithm for PMSA by uti...

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IEEE/ASME (AIM) International Conference on Advanced Intelligent Mechatronics

作者： Liang Yan Bo Zhu Zongxia Jiao Chin-Yin Chen I-Ming Chen School of Automation Science and Electrical Engineering Research Institute of Beihang University in Shenzhen Shenzhen China Institute of Advanced Manufacturing Technology Ningbo Institute of Material Technology and Engineering Ningbo China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore

ISBN: (纸本)9781467391085

This paper proposes a permanent magnet spherical actuator (PMSA) with three-dimensional magnet array. The application of 3D magnet array improves the output torque significantly. However, as PMSA is a multivariable and nonlinear system, it is very complicate to achieve high accuracy control. Therefore, a novel single neural adaptive control algorithm is proposed in this paper. Compared with the PD and PID control methods, the proposed algorithm is able to realize self-adaptive to the perturbation, which improves the motion stability of PMSA a lot. Euler angles are applied to describe the orientation of rotor. Lagrange equations are utilized to establish the dynamic model of the actuator. As the center of gravity does not coincide with the center of rotor sphere, gravity torque is taken into consideration to enhance the precision of dynamic model. The stability of this algorithm is validated with detailed derivation. Simulation model is formulated in Matlab/Simulink. It proves that the proposed algorithm can make the system track the continuous trajectories in high accuracy.

关键词： Torque Rotors Heuristic algorithms Mathematical model Actuators PD control Three-dimensional displays

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Magnetic field analysis of permanent magnet tubular linear machines with multiple movers

Magnetic field analysis of permanent magnet tubular linear m...

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IEEE/ASME (AIM) International Conference on Advanced Intelligent Mechatronics

作者： Liang Yan Tianyu Wang Zongxia Jiao Chin-Yin Chen I-Ming Chen School of Automation Science and Electrical Engineering Research Institute of Beihang University in Shenzhen Guangdong China Institute of Advanced Manufacturing Technology Ningbo Institute of Material Technology and Engineering Ningbo China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore

ISBN: (纸本)9781467391085

Conventional linear machine consists of only one stator and one mover. In this paper, a permanent magnet (PM) tubular linear motor with multiple movers is proposed to improve the efficiency of stator field. The outer and inner movers can produce independent motions by interacting with the PM stator. It can be used in large systems requiring multiple driven elements and space saving. The employment of tubular structure helps to reduce the flux leakage and improve the system working efficiency. The design concept and operating principle of the proposed linear machine are introduced. The magnetic field distribution in the machine is formulated by using Laplace's and Poisson's equations of magnetic vector potential. Following that, the modeling of force output for this machine is obtained based on Lorentz law. Numerical computation is also conducted on the flux field. It shows that the derived analytical model fits with the result of finite element analysis (FEA) well.

关键词： Magnetic fields Manganese Force Windings Stators Mathematical model Magnetic flux

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Dynamic modeling of a 2D compliant link for safety evaluation in human-robot interactions

Dynamic modeling of a 2D compliant link for safety evaluatio...

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IEEE/RSJ International Conference on Intelligent Robots and systems

作者： Yu She Deshan Meng Hongliang Shi Hai-Jun Su Graduate Research Associates of Dept. of Mechanical and Aerospace Engineering The Ohio State University Columbus OH USA Graduate Student of Dept. of Mechanical and Automation Harbin Institute of Technology Shenzhen Graduate School Guangdong Shenzhen P.R. China Associate Professor of Dept. of Mechanical and Aerospace Engineering The Ohio State University Columbus OH USA

In this article, we build dynamic models of 2D compliant links to evaluate injury level in a human-robot interaction. Safety is a premium concern for co-robotic systems. It has been studied that using compliant links in a robot can greatly reduce the injury level. Since most safety criteria are based on tolerance of acceleration of the operator's head during the impact, an efficient and yet accurate dynamic model of compliant links is needed. In this paper, we compare three dynamic models for calculating acceleration and head injury criterion: the compliant Beam-Spring-Mass (BSM) model, the Mass-Spring-Mass (MSM) model and the Link-Spring-Mass (LSM) model. For the MSM model and LSM model, we obtain analytic expressions of acceleration. While numerical results are achieved for the compliant BSM model. To develop the compliant BSM model, we compared three different methods: the Pseudo-Rigid-Body (PRB) model, the Finite-Segment-Model (FSM), and the Assumed-Mode-Method (AMM). Finally, all these models are validated by human-robot impact simulation programs built in Matlab. The acceleration from these simulations can be used to quantitatively measure the injury level during an impact.

关键词： Mathematical model Robots Acceleration Injuries Numerical models Springs Dynamics

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Robust unscented fusion filter using fuzzy adaptation rule 13

Robust unscented fusion filter using fuzzy adaptation rule

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13th European Control Conference, ECC 2014

作者： Kang, Chul Woo Park, Chan Gook Automation and System Research Institute Seoul National University Seoul Korea Republic of School of Mechanical and Aerospace Engineering Seoul National University Korea Korea Republic of

ISBN: (纸本)9783952426913

This paper presents a new robust estimation approach for nonlinear systems. Former approaches to robust nonlinear estimation such as the unscented H ∞filter(UHF) [1] perform well on in disturbed nonlinear systems. However, with regard to undisturbed systems, the performance of robust nonlinear filters has proven inferior to that of conventional nonlinear filters. In this paper, a new filter is proposed which performs well on both disturbed and undisturbed systems by integrating a UHF and an unscented Kalman filter (UKF). The proposed filter uses a hybrid filter structure for the proper integration of the two local filters;a fuzzy-based mode adaptation rule is also implemented to improve performance.

关键词： Nonlinear systems

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A GNSS interference identification and tracking based on adaptive fading Kalman filter 19

A GNSS interference identification and tracking based on ada...

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19th IFAC World Congress on International Federation of Automatic Control, IFAC 2014

作者： Kang, Chang Ho Kim, Sun Young Park, Chan Gook Department of Mechanical and Aerospace Engineering Automation and Systems Research Institute Seoul National University Seoul Korea Republic of

ISBN: (纸本)9783902823625

A time domain signal tracking algorithm is proposed to estimate the frequency of a chirp type global navigation satellite system (GNSS) interference. The unknown interference frequency of GNSS is estimated by the received signal using properties of trigonometrical functions, but this value has a lot of error caused by measurement noise and the frequency change of the interference. In order to reduce the ierror, an adaptive fading Kalman filter is applied to the proposed algorithm. Furthermore, a low pass differentiator (LPD) and a pattern enhancement algorithm are used to estimate the sweep period of chirp type interference. The performance of the tracking algorithm is verified by comparing to conventional algorithms. By analyzing the results of comparisons, the proposed algorithm has better tracking performance than conventional algorithms when the jammer to signal ratio (J/S) of GNSS interference signal is more than 30dB, which seriously affects the accuracy of the GNSS. © IFAC.

关键词： Global positioning system

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Harmonic elimination for multilevel converter with Groebner bases and symmetric polynomials

Harmonic elimination for multilevel converter with Groebner ...

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IEEE Energy Conversion Congress and Exposition, ECCE

作者： Kehu Yang Qi Zhang Ruyi Yuan Wensheng Yu Jin Wang School of Mechanical Electronic and Information Engineering China University of Mining and Technology Beijing Integrated Information System Research Center Institute of Automation Chinese Academy of Sciences School of Electronic Engineering Beijing University of Posts and Telecommunications Department of Electrical and Computer Engineering The Ohio State University

Selective harmonic elimination technology has been widely used in many medium and high power converters which operating at very low switching frequency, however, it is still a challenging work to solve the switching angles from a group of nonlinear transcendental equations, especially for the multilevel converters. In this paper, an algebraic method is proposed for selective harmonic elimination. First, the order of the SHE equations is reduced by using the symmetric polynomials theory, and then, its Groebner bases is computed. After this two conversions, the solving of multivariable high order SHE equations is converted to solve two univariate equations and a set of univariate linear equations which simplifies the solving procedure dramatically and abandon the requirement on initial values and can find all the solutions. Compared with the existing algebraic method, such as the resultant elimination method, the calculation efficiency is improved. Experimental verification is also shown in this paper.

关键词： Polynomials Mathematical model Harmonic analysis Switches Inverters Modulation Software algorithms

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