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基于Paden-Kahan子问题的冗余度机器人运动学求解

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机器人 2004年第3期26卷 250-255页

作者：杨明明陈伟海于守谦武桢北京航空航天大学自动化科学与电气工程学院北京100083 北京航空航天大学机器人研究所北京100083

针对 7DOF机器人的逆运动学求解问题 ,提出了一种可提高运动控制精度的混合算法 .这种算法使用旋量理论来描述机器人的运动 .它首先求出对运动学性能指标进行优化的速度级逆解 ;然后固定一个特殊关节 ,将问题转化为非冗余度机器人的运... 详细信息

针对 7DOF机器人的逆运动学求解问题 ,提出了一种可提高运动控制精度的混合算法 .这种算法使用旋量理论来描述机器人的运动 .它首先求出对运动学性能指标进行优化的速度级逆解 ;然后固定一个特殊关节 ,将问题转化为非冗余度机器人的运动控制 ,应用Paden Kahan子问题法得到逆运动学封闭解 .通过仿真实例。

关键词：冗余度机器人运动学 Paden-Kahan子问题运动控制逆解

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基于DTC的UCAV任务规划方法研究

系统仿真学报 2009年第6期21卷 1565-1569页

作者：廖沫陈宗基中国运载火箭技术研究院研究发展中心北京100076 北京航空航天大学自动化科学与电气工程学院北京100083

无人作战飞机(Uninhabited Combat Aerial Vehicle,UCAV)任务规划是指在执行任务之前制定UCAV行动的步骤,是实现UCAV智能化和自主化的必要的条件。以任务分析和环境建模仿真框架(Task Analysis Environment Modeling and Simulation,TAEMS)作为任务结构的描述模型,实现UCAV的任务模型描述并给出了UCAV任务规划问题描述。提出基于DTC(Design to Criteria)的UCAV任务规划算法,并在任务规划过程中集成路径规划,DTC算法是一种启发式算法,任务规划的结果是完成UCAV任务所需要执行的动作序列。仿真实例证明了任务规划算法的可行性。

关键词：无人作战飞机任务规划路径规划 TAEMS DTC

The Study and Analysis on ARAIM Performance

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The Study and Analysis on ARAIM Performance

PERFORMANCE EVALUATION OF SEVERAL FUSION APPROACHES FOR CCD/SAR IMAGES

第三届中国卫星导航学术年会

作者： Niu Fei* 1, 2 Zhang Yisheng 3 Yang Long 1 Fan Mei jun 1 Fan Jianjun 1 1. beijing Global Information Center of Application and Exploitation, beijing, china,100094 2. school of automation science and electrical engineering, beijing university of aeronautics and astronautics, beijing, china, 100083 3. beijing Institute of Application Weather, beijing, china, 100094

Receiver autonomous integrity monitoring （RAIM） is the key approach to monitor the integrity of Global Navigation Satellite System （GNSS）. Advanced RAIM （ARAIM） is the upgrade. The paper focuses on the ARAIM algorithm and tries to make some progress. According simulation and analysis, the performance of ARAIM is validated. It is showed that ARAIM method based on double constellations is effective for the users requiring high level of integrity, continuity and availability. When UERE is better than 2 meters, the performance of LPV-200 can be achieved without ground monitoring station net.

关键词： GNSS ARAIM Integrity

来源： cnki会议评论

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Chinese Geographical science 2003年第1期13卷 91-96页

作者： WANG Yan-li, CHEN Zhe(school of automation science and electrical engineering, beijing university of aeronautics and astronautics, beijing 100083, P. R. china) school of automation science and electrical engineering， beijing university of aeronautics and astronautics， beijing 100083， P. R. china

Several image fusion approaches for CCD/SAR images are studied and the performance evaluation of these fusion approaches is completed in this paper. Firstly, the preprocessing of CCD/SAR images before fusion is fulfilled. Then, the image fusion methods including linear superposition, nonlinear operator method and multiresolution methods, of which the multiresolution methods include Laplacian pyramid, ratio pyramid, contrast pyramid, gradient pyramid, morphological pyramid and discrete wavelet transform, are adopted to fuse two types of images. Lastly, the four performance measures, standard deviation, entropy, cross entropy and spatial frequency, are calculated to compare the fusion results by different fusion approaches in this paper. Experimental results show that contrast pyramid, morphology pyramid and discrete wavelet transformation in multiresolution approaches are more suitable for CCD/SAR image fusion than other ones proposed in this paper and the objective performance evaluation of CCD/SAR image fusion approaches are effective.

关键词： image fusion performance evaluation CCD image SAR image

Adaptive RBF neural network control of robot with actuator nonlinearities

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控制理论与应用（英文版） 2010年第2期8卷 249-256页

作者： Jinkun LIU, Yu LU (school of automation science and electrical engineering, beijing university of aeronautics and astronautics, beijing 100191, china) school of automation science and electrical engineering Beijing University of Aeronautics and Astronautics Beijing China

In this paper, an adaptive neural network control scheme for robot manipulators with actuator nonlinearities is presented. The control scheme consists of an adaptive neural network controller and an actuator nonlinearities compensator. Since the actuator nonlinearities are usually included in the robot driving motor, a compensator using radial basis function (RBF) network is proposed to estimate the actuator nonlinearities and eliminate their effects. Subsequently, an adaptive neural network controller that neither requires the evaluation of inverse dynamical model nor the time-consuming training process is given. In addition, GL matrix and its product operator are introduced to help prove the stability of the closed control system. Considering the adaptive neural network controller and the RBF network compensator as the whole control scheme, the closed-loop system is proved to be uniformly ultimately bounded (UUB). The whole scheme provides a general procedure to control the robot manipulators with actuator nonlinearities. Simulation results verify the effectiveness of the designed scheme and the theoretical discussion.

关键词： Adaptive control RBF neural network Actuator nonlinearity Robot manipulator Deadzone

Quasi-equality constrained risk-sensitive filtering for nonlinear discrete-time systems

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控制理论与应用（英文版） 2012年第2期10卷 229-235页

作者： Linfeng SHEN, Yan LIN school of automation science and electrical engineering, beijing university of aeronautics and astronautics, beijing 100191, china school of automation science and electrical engineering Beijing University of Aeronautics and Astronautics Beijing China

More and more data fusion models contain state constraints with valuable information in the filtering process. In this study, an optimal filter of risk sensitive with quasi-equality constraints is formulated using the reference probability method. Through recursion processes of probability density acquired from the probability measure change, the derived algorithm is optimal in the sense of the risk sensitive parameter. The system and constraint models are Consistent in statistics. Simulation results show that it is more robust and efficient than projection filters for the worst-case of noises and model uncertainty.

关键词： Optimal estimation Risk-sensitive filtering Constraints

Nonlinear Aeroelastic Response of High-aspect-ratio Flexible Wings

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Chinese Journal of aeronautics 2009年第4期22卷 355-363页

作者： Zhang Jian,Xiang Jinwu school of Aeronautic science and engineering,beijing university of aeronautics and astronautics,beijing 100191,china [a]school of Aeronautic science and engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

The aeroelastic analysis of high-altitude, long-endurance （HALE） aircraft that features high-aspect-ratio flexible wings needs take into account structural geometrical nonlinearities and dynamic stall. For a generic nonlinear aeroelastic system, besides the stability boundary, the characteristics of the limit-cycle oscillation （LCO） should also be accurately predicted. In order to conduct nonlinear aeroelastic analysis of high-aspect-ratio flexible wings, a first-order, state-space model is developed by combining a geometrically exact, nonlinear anisotropic beam model with nonlinear ONERA （Edlin） dynamic stall model. The present investigations focus on the initiation and sustaining mechanism of the LCO and the effects of flight speed and drag on aeroelastic behaviors. Numerical results indicate that structural geometrical nonlinearities could lead to the LCO without stall occurring. As flight speed increases, dynamic stall becomes dominant and the LCO increasingly complicated. Drag could be negligible for LCO type, but should be considered to exactly predict the onset speed of flutter or LCO of high-aspect-ratio flexible wings.

关键词： nonlinear aeroelasticity limit-cycle oscillation Galerkin methods geometrical nonlinearities dynamic stall HALEaircraft

Key Parameters and Conceptual Configuration of Unmanned Combat Aerial Vehicle Concept

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Chinese Journal of aeronautics 2009年第4期22卷 393-400页

作者： Wang Ganglin Faculty 513,school of Aeronautic science and engineering,beijing university of aeronautics and astronautics,beijing 100191,china [a]Faculty 513 School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

The nature and characteristics of attack unmanned combat aerial vehicle （UCAV） are analyzed. The principles of selecting takeoff thrust-weight ratio and takeoff weight of attack UCAV are presented by analyzing the statistical data of weights for various main combat aircraft. The UCAV airborne weapons are analyzed, followed by the preliminary estimation of the payload weight. Various typical engines are analyzed and one of them is selected. Then the takeoff weight of the UCAV is determined. Based on some basic parameters and assumptions, the qualitative decomposition calculation for takeoff weight is completed. The key factors for obtaining longer endurance of aircraft with small aspect ratio configuration are found to be high lift-drag ratio and internal space. On the basis of the conclusions mentioned above, a highly blended flying-wing plus lifting body concept is proposed. According to this concept, the UCAV configuration is designed and optimized. Finally, the UCAV configuration with small aspect ratio, high lift-drag ratio, and high stealth characteristic is obtained.

关键词： aircraft design unmanned aerial vehicles unmanned combat aerial vehicles conceptual design aerodynamicsstealth

Stability on Finite Time interval andTime-Dependent Bifurcation Analysis ofDuffing's Equations

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Communications in Nonlinear science and Numerical Simulation 1999年第4期4卷 268-271页

作者： Cuncai HUA Qishan LU(school of science, beijing university of aeronautics and astronautics, beijing 100083,china) school of science Beijing Univ. Aero. and Astronaut. Beijing 100083 China

IntroductionInPhysics,Mechanicsandengineering,ChemistryandLifescienceetc.,thereealstbfforcationproblemsm***etimepassingthrought... 详细信息

IntroductionInPhysics,Mechanicsandengineering,ChemistryandLifescienceetc.,thereealstbfforcationproblemsm***etimepassingthrought...

关键词： stability on finite time interval time-dependent bifurcation Duffing’s equa-tion