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Kinematics analysis of a novel all-attitude flight simulator

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Science china(Information Sciences) 2010年第2期53卷 236-247页

作者： WANG XiaoChen , ZHAO Hui, MA KeMao, HUO Xin & yao yu control and simulation center, harbin institute of technology, harbin 150080, china control and simulation center Harbin Institute of Technology Harbin China

To overcome the kinematic singularity limitation of simulator, which is unavoidable in a three-axis architecture, an all-attitude flight simulator in a four-axis architecture is proposed. The simulator can always provide 3DOF motion by applying redundant manipulator mechanism. For direct kinematics of the manipulator, a dual-Euler method is adopted to solve the expressions of attitude angles; thus computation singularity of all- attitude angles is overcome. For inverse kinematics of the manipulator, pseudo-inverse gradient projection method is used to obtain optimal velocity solution. Then, based on dynamic control method, optimal position solution is obtained. The proposed inverse kinematics algorithm can achieve desired attitudes, as well as can avoid kinematics singularity and axis angle limits. The simulation results show that the kinematic performance of the four-axis all-attitude flight simulator is superior to that of a three-axis simulator.

关键词： all-attitude flight simulator kinematic singularity direct kinematics inverse kinematics

Integrated guidance and control design of a flight vehicle with side-window detection

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Chinese Journal of Aeronautics 2018年第4期31卷 749-764页

作者： Tianyu ZheNG yu yao fenghua he denggao ji Department of Astronautics Harbin Institute of Technology Harbin 150080 China Beijing institute of Nearspace Vehicle's Systems Engineering Beijing 100083 China

This paper considers the guidance and control problem of a flight vehicle with sidewindow detection. In order to guarantee the target remaining in the seeker＇s sight of view, the line of sight and the attitude of the flight vehicle should be under some constraints caused by the sidewindow, which leads to coupling between the guidance and the attitude dynamics model. To deal with the side-window constraints and the coupling, a novel Integrated Guidance and control（IGC）design approach is proposed. Firstly, the relative motion equations are derived in the body-Line of Sight（LOS） coordinate system. And the guidance and control problem of the flight vehicle is formulated into an IGC problem with state constraints. Then, based on the singular perturbation method, the IGC problem is decomposed into the control design of the quasi-steady-state subsystem and the boundary-layer subsystem which can be designed separately. Finally, the receding horizon control is applied to the control design for the two subsystems. simulation results show the effectiveness of the proposed approach.

关键词： Integrated guidance and control Receding horizon control Side-window detection Singular perturbation Terminal guidance

Taming heat with tiny pressure

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The Innovation 2024年第2期5卷 70-78页

作者： Kun Zhang Zhe Zhang Hailong Pan Haoyu Wang Xueting Zhao ji Qi Zhao Zhang Ruiqi Song Chenyang yu Biaohong Huang Xujing Li Huaican Chen Wen Yin Changlong Tan Weijin Hu Michael Wüubbenhorst jiangshui Luo Dehong yu Zhidong Zhang Bing Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Laboratory for Soft Matter and Biophysics Department of Physics and AstronomyKU Leuven3001 LeuvenBelgium institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science center Dongguan 523803China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150080China Australian Nuclear Science and technology Organisation Lucas HeightsNSW 2234Australia

heat is almost everywhere.Unlike electricity,which can be easily manipulated,the current ability to control heat is still highly limited owing to spontaneous thermal dissipation imposed by the second law of thermodynamics.Optical illumination and pressure have been used to switch endothermic/exothermic responses of materials via phase transitions;however,these strategies are less cost-effective and unscalable.here,we spectroscopically demonstrate the glassy crystal state of 2-amino-2-methyl-1,3-propanediol(AMP)to realize an affordable,easily manageable approach for thermal energy recycling.The supercooled state of AMP is so sensitive to pressure that even several megapascals can induce crystallization to the ordered crystal,resulting in a substantial temperature increase of 48 K within 20 s.Furthermore,we demonstrate a proof-of-concept device capable of programable heating with an extremely high work-to-heat conversion effi-ciency of383.Such delicate and efficient tuning of heat may remarkably facilitate rational utilization of waste heat.

关键词： illumination thermal rational

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一种新型动态飞行过载模拟器及其运动学分析

系统仿真学报 2009年第S2期21卷 112-114页

作者：马杰姚郁哈尔滨工业大学控制与仿真中心哈尔滨150080

提出了一种新型的飞行过载模拟器,该模拟器由一个圆盘式离心机和一个三轴转台组成。与现有的飞行过载模拟器相比,该系统可以精确地提供连续快速动态变化的过载。对提出的机构进行了运动学的建模,给出了负载敏感轴的加速度的表达式。并... 详细信息

提出了一种新型的飞行过载模拟器,该模拟器由一个圆盘式离心机和一个三轴转台组成。与现有的飞行过载模拟器相比,该系统可以精确地提供连续快速动态变化的过载。对提出的机构进行了运动学的建模,给出了负载敏感轴的加速度的表达式。并且针对系统设计的几个关键问题,给出了切实可行的解决方案。

关键词：动态过载仿真飞行仿真运动学分析运动模拟器

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新型仿真转台设计方案研究

系统仿真学报 2009年第S2期21卷 129-132页

作者：马杰姚郁哈尔滨工业大学控制与仿真中心哈尔滨150080

结合目前先进武器制导系统半实物仿真的需求,分析了传统三轴转台及模拟弹目相对运动的五轴仿真转台结构设计中由于机械干涉造成转角范围过小的问题,提出了带有船形结构的新型三轴转台以及带有同轴套装结构的立式五轴转台、卧式五轴转台... 详细信息

结合目前先进武器制导系统半实物仿真的需求,分析了传统三轴转台及模拟弹目相对运动的五轴仿真转台结构设计中由于机械干涉造成转角范围过小的问题,提出了带有船形结构的新型三轴转台以及带有同轴套装结构的立式五轴转台、卧式五轴转台的结构方案,有效地解决了传统仿真转台难以达到的大视场角、大范围的目标俯仰运动模拟等难题,为适应新型武器系统半实物仿真试验需求提供了有力的技术保障。

关键词：仿真转台运动模拟半实物仿真系统仿真

Temperature inversion enables superior stability for low-temperature Zn-ion batteries

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Journal of Energy Chemistry 2024年第4期91卷 245-253页

作者： Fu-Da yu Zhe-jian Yi Rui-Yang Li Wei-Hao Lin jie Chen Xiao-yue Chen Yi-Ming Xie ji-Huai Wu Zhang Lan Lan-Fang Que Bao-Sheng Liu Hao Luo Zhen-Bo Wang Engineering Research center of Environment-Friendly Functional Materials Ministry of EducationInstitute of Materials Physical ChemistryHuaqiao UniversityXiamen 361021FujianChina b2 School of Electronic Engineering Guangxi University of Science and TechnologyLiuzhou 545006GuangxiChina School of Materials Science and Engineering Xiamen University of TechnologyXiamen 361024FujianChina School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina MIIT Key Laboratory of Critical Materials technology for New Energy Conversion and Storage State Key Laboratory of Space Power-SourcesSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001HeilongjiangChina College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071GuangdongChina

It is challenging for aqueous Zn-ion batteries(ZIBs)to achieve comparable low-temperature(low-T)performance due to the easy-frozen electrolyte and severe Zn dendrites.herein,an aqueous electrolyte with a low freezing point and high ionic conductivity is proposed.Combined with molecular dynamics simulation and multi-scale interface analysis(time of flight secondary ion mass spectrometry threedimensional mapping and in-situ electrochemical impedance spectroscopy method),the temperature independence of the V_(2)O_(5)cathode and Zn anode is observed to be opposite.Surprisingly,dominated by the solvent structure of the designed electrolyte at low temperatures,vanadium dissolution/shuttle is significantly inhibited,and the zinc dendrites caused by this electrochemical crosstalk are greatly relieved,thus showing an abnormal temperature inversion effect.Through the disclosure and improvement of the above phenomena,the designed Zn||V_(2)O_(5)full cell delivers superior low-T performance,maintaining almost 99%capacity retention after 9500 cycles(working more than 2500 h)at-20°C.This work proposes a kind of electrolyte suitable for low-T ZIBs and reveals the inverse temperature dependence of the Zn anode,which might offer a novel perspective for the investigation of low-T aqueous battery systems.

关键词： Aqueous Zn-ion batteries Low-temperature performance Opposite temperature dependence Zndendrite growth Vanadium dissolution

control Design for Harmonic Disturbance Rejection for Robot Manipulators with Bounded Inputs

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Chinese Journal of Mechanical Engineering 2011年第2期24卷 248-256页

作者： yao yu WANG Xiaochen he fenghua control and simulation center Harbin Institute of Technology Harbin 150080 China

Currently most of control methods are of one degree of freedom（1-DOF） control structure for the robot systems which are affected by unmeasurable harmonic disturbances,at the same time in order to obtain perfect disturbance attenuation level,the controller gain must be increased.In practice,however,for robotic actuators,there are physical constraints that limit the amplitude of the available torques.This paper considers the problem of tracking control under input constraints for robot manipulators which are affected by unmeasurable harmonic disturbances.A new control scheme is proposed for the problem,which is composed of a parameter-dependent nonlinear observer and a tracking controller.The parameter-dependent nonlinear observer,designed based on the internal model principle,can achieve an estimation and compensation of a class of harmonic disturbances with unknown frequencies.The tracking controller,designed via adaptive control techniques,can make the systems asymptotically track the desired trajectories.In the control design,the continuous piecewise differentiable increasing function is used to limit control input amplitude,such that the control input saturation is avoided.The Lyapunov stability of closed loop systems is analyzed.To validate proposed control scheme,simulation results are provided for a two link horizontal robot manipulator.The simulation results show that the proposed control scheme ensures asymptotic tracking in presence of an uncertain external disturbance acting on the system.An important feature of the methodology consists of the fact that the designed controller is of 2-DOF control structure,namely,it has the ability to overcome the conflict between controller gain and robustness against external disturbances in the traditional 1 -DOF control structure framework.

关键词： tracking control of robot harmonic disturbance rejection internal model principle input constraint adaptive control

Robust H∞ Performance Analysis Framework for a Missile Terminal Guidance System

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Robust H∞ Performance Analysis Framework for a Missile Term...

Robust Guaranteed Cost control for Sampled-data Systems with Parametric Uncertainties

第二十七届中国控制会议

作者： ji denggao,he fenghua,yao yu,Liu Fuchun control and simulation center,harbin institute of technology,harbin 150080,P.R.china

In this paper,robust H-like performance of a missile terminal guidance system that incorporates non-zero initial conditions and terminal constraints is analyzed over a finite horizon.This is done by defining a worst-case performance measure. Necessary and sufficient conditions,which guarantee that the above mentioned performance measure is less than a prespecified value,are given in terms of solvability of differential linear matrix inequalities(DLMI) .Finally,based on the new H metric,many uncertainties such as target maneuvers,heading error,and parameter variations in the missile terminal guidance are fully considered.Therefore,a more accurate performance prediction is obtained in contrast to covariance analysis.

关键词： Terminal guidance Differential linear matrix inequality H∞ performance with transients Miss distance

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Robust Guaranteed Cost Control for Sampled-data Systems with...