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Physical analysis and numerical simulation for the dynamic behaviour of vehicles in pitching oscillations or rocking motions

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Science china(Technological Sciences) 2007年第4期50卷 385-401页

作者： ZHANG HanXin1,2.3. ZHANG Zhao1,3. YUAN XianXu1,2. LIU Wei1, XIE YuFei1,2.& YE YouDa1,2.1 china Aerodynamics Research and Development Center, Mianyang 62.000, china 2.National laboratory for Computational Fluid dynamics, beijing University of Aeronautics and Astronautics, beijing 100083. china 3.School of aerospace, Tsinghua University, beijing 100084, china 1. china Aerodynamics Research and Development Center Mianyan 621000 China 2. National laboratory for Computational Fluid dynamics Beijing University of Aeronautics and Astronautics Beijing 100083 China 3. School of aerospace Tsinghua University Beijing 100084 China

Analytical methods of nonlinear dynamics and numerical simulations for the cou-pling equations of Navier-Stokes and flight mechanics are used to study the dynamic behaviour of pitching motions of reentry capsules with the variation of Mach number, and rocking motions of swept wings with the variation of angle of attack. Conditions under which the dynamic instability, Hopf bifurcation and saddle-node bifurcation occur are obtained. The node-saddle-node topological structure in the phase portrait, i.e. the state of bi-attractors (attracting basins) is described. The evolving process of dynamic behaviour and flow fields are given. The theories are compared with some numerical simulations conducted by the authors. Besides, some verifiable experi-mental results are cited. The agreement between them is very well.

关键词： physical analysis numerical simulation pitching oscillation rocking motion bifurcation

Fuzzy tracking control design for hypersonic vehicles via T-S model

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Science china(Information Sciences) 2011年第3期54卷 521-528页

作者： GAO DaoXiang 1 & SUN ZengQi 2.1 School of technology, beijing Forestry University, beijing 100083. china 2.State Key laboratory of Intelligent technology and System, Department of Computer Science and technology, Tsinghua University, beijing 100084, china 1. School of technology Beijing Forestry University Beijing 100083 China2. State Key Laboratory of Intelligent Technology and System Department of Computer Science and Technology Tsinghua University Beijing 100084 China

The main focus of this paper is on designing a T-S fuzzy controller for the hypersonic vehicle. The longitudinal dynamics of the vehicle are studied using time-scale decomposition to reduce the complexity of T-S modeling. The dynamic inversion with PI control technique is applied for the slow dynamics to derive the {2. path angle command and throttle setting by taking the pilot altitude and velocity command as its inputs. The T-S fuzzy controller is designed for the fast dynamics to derive the elevator deflection to track the {2. path angle command. The discrepancy between the T-S model and real vehicle model is considered by using sliding mode control for the system stability. Simulation results are included to show the effectiveness of the controller.

关键词： fuzzy control T-S model sliding mode control hypersonic vehicle

Adaptive neural control based on HGO for hypersonic flight vehicles

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Science china(Information Sciences) 2011年第3期54卷 511-520页

作者： XU Bin 1,2., GAO DaoXiang 3.& WANG ShiXing 1 1 Department of Computer Science and technology, Tsinghua University, beijing 100084, {2. 2.Autonomous System Lab, ETH Zurich Zurich 8092. Switzerland 3.School of technology, beijing Forestry University, beijing 100083. {2. 1. Department of Computer Science and technology Tsinghua University Beijing 100084 China2. Autonomous System Lab ETH Zurich Zurich 8092 Switzerland3. School of Technology Beijing Forestry University Beijing 100083 China

This paper describes the design of adaptive neural controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV) which are decomposed into two functional systems, namely the altitude subsystem and the velocity subsystem. For each subsystem, one adaptive neural controller is investigated based on the normal output-feedback formulation. For the altitude subsystem, the high gain observer (HGO) is taken to estimate the unknown newly defined states. Only one neural network (NN) is employed to approximate the lumped uncertain system nonlinearity during the controller design which is considerably simpler than the ones based on back-stepping scheme with the strict-feedback form. The Lyapunov stability of the NN weights and filtered tracking error are guaranteed in the semiglobal sense. Numerical simulation study of step response demonstrates the effectiveness of the proposed strategy in spite of system uncertainty.

关键词： adaptive neural control hypersonic flight vehicle high gain observer output-feedback

Processing Method and Verification of Local Correlation for Spacecraft DOR signals

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Processing Method and Verification of Local Correlation for ...

Second-order consensus in networks of dynamic agents with communication time-delays

第三届中国卫星导航学术年会

作者： Lue Chen1,2., Geshi Tang1,2. Songtao Han1,2. Mei Wang1,2. Fei Fan3.. Science and technology on aerospace {2. dynamics laboratory, beijing 100094,china2. beijing aerospace Control Center, beijing 100094, china3. beijing Institute of Tracking and Telecommunication technology, beijing 100094, china

Differential One-way Ranging （DOR） is an interferometry method to obtain high precision delay in deep space exploration. Two stations track the same spacecraft to obtain high precision deep space spacecraft’s angle information. The process of DOR signal local correlation processing shows as follows, the model of DOR local signal is firstly constructed, then this model is used to do local correlation processing with the received spacecraft’s radio signal, to obtain high precision delay. Compared with the traditional DOR method, DOR local correlation processing method can be more effective in low SNR conditions to get correct measurement information. Firstly, prior delay model is calculated by orbit prediction, and the spacecraft’s emission frequency is calculated through effective frequency evaluation method, then the prior delay model and emission frequency are used to construct the DOR local model signal, then correlation phase is extracted by cross-correlation processing, finally, DOR group delay is calculated. This paper introduces the mathematical model of DOR local correlation processing in detail, and especially analyzes the technical difficulty in DOR local correlation processing. Based on the theoretical analysis, the algorithm of DOR local correlation processing is executed, and this method is verified by simulation,with the simulation measurement precision is about 0.1 ns,this verifies the effectiveness of DOR local correlation processing, and provides an effective technology for precise spacecraft orbit measurement.

关键词： Differential One-way Ranging local correlation processing,correlation phase, group delay

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Journal of Systems Engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2. Huajing Fang3. and Hua Wang4 1. School of Navigation, Wuhan University of technology, Wuhan 43.063. P. R. china 2. Wuhan Second Ship Design and Research Institute, Wuhan 43.064, P. R. china 3. Department of Control Science and Engineering, Huazhong University of Science and technology, Wuhan 43.074, P. R. china 4. Department of aerospace and Mechanical Engineering, Boston University, Boston MA02.15, USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China Wuhan Second Ship Design and Research Institute Wuhan 430064 E R. China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China Department of aerospace and Mechanical Engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

Design of multiple anti-windup loops for multiple activations

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Science china(Information Sciences) 2012年第9期55卷 1925-1934页

作者： WU XiongJun 1,2.& LIN Zongli 3.1 1 Department of Automation,Shanghai Jiao Tong University,and Key laboratory of System Control and Information Processing,Ministry of Education of china,Shanghai 2.02.0,china 2.No.802.Institute of Shanghai Academy of Space flight technology,the Eighth Academy of china aerospace Science and technology Corporation,Shanghai 2.0090,china 3.Charles L.Brown Department of Electrical and Computer Engineering,University of Virginia,P.O.Box 400743.Charlottesville,VA 2.904-4743.USA 1. Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai 200240 China2. No. 802 Institute of Shanghai Academy of Space Flight Technology the Eighth Academy of China Aerospace Science and Technology Corporation Shanghai 200090 China3. Charles L. Brown Department of Electrical and Computer Engineering University of Virginia P.O. Box 400743 Charlottesville VA 22904-4743 USA

This paper considers anti-windup design for linear systems subject to actuator *** anti-windup gains are designed for activations immediately at the occurrence actuator saturation,after the saturation has reached a certain level and in anticipation of the occurrence of saturation,*** design is based on the minimization of L 2.gain from the disturbance to the controlled output of the resulting closed-loop *** anti-windup scheme involves a single anti-windup loop for immediate activation.A recent innovation is to design a single anti-windup loop for delayed or anticipatory activation,as well as to design two anti-windup gains,one for immediate activation and one for delayed *** design of three anti-windup gains for three different activations is shown through simulation to lead to significant further performance improvement over the previous activation schemes.

关键词： actuator saturation anti-windup anticipatory activation delayed activation L 2.gain nonlinear control

Experimental demonstration of a new concept of drag reduction and thermal protection for hypersonic vehicles

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Acta Mechanica Sinica 2009年第3期25卷 417-419页

作者： Zonglin Jiang Yunfeng Liu Guilai Han Wei Zhao Key laboratory of High Temperature Gas dynamics, Institute of Mechanics, Chinese Academy of Sciences, 100190 {2., {3. Key laboratory of High Temperature Gas dynamics Institute of Mechanics Chinese Academy of Sciences 100190 Beijing China

A new idea of drag reduction and thermal protection for hypersonic vehicles is proposed based on the combination of a physical spike and lateral jets for shockreconstruction. The spike recasts the bow shock in front of a blunt body into a conical shock, and the lateral jets work to protect the spike tip from overheating and to push the conical shock away from the blunt body when a pitching angle exists during flight. Experiments are conducted in a hypersonic wind tunnel at a nominal Mach number of 6. It is demonstrated that the shock/shock interaction on the blunt body is avoided due to injection and the peak pressure at the reattachment point is reduced by 70% under a 4° attack angle.

关键词： Hypersonic vehicle Shock-reconstruction. Drag reduction Thermal protection Spike and lateral jets

Review on abort trajectory for manned lunar landing mission

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Science china(Technological Sciences) 2010年第10期53卷 2691-2698页

作者： XI XiaoNing1, HUANG WenDe2.& WANG Wei2.3.1 College of Mechatronics Engineering and Automation, National University of Defense technology, Changsha 410073. {3. 2.College of {2. and Material Engineering, National University of Defense technology, Changsha 410073. {3. 3.School of Surveying and Spatial Information System, University of New South Wales, Sydney, NSW 2.52. Australia 1. College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China2. College of Aerospace and Material Engineering National University of Defense Technology Changsha 410073 China3. School of Surveying and Spatial Information System University of New South Wales Sydney NSW 2052 Australia

Abort trajectory is a passage that ensures the astronauts to return safely to the earth when an emergency occurs. Firstly,the essential elements of mission abort are analyzed entirely based on summarizing the existing studies. Then,abort trajectory requirement and rational selection for different flight phases of typical manned lunar mission are discussed specifically. Considering a trade-off between the two primary constrains of an abort,the return time of flight and energy requirement,a general optimizing method for mission abort is proposed. Finally,some suggestions are given for {2.’s future manned lunar landing mission.

关键词： manned lunar landing mission abort trajectory design free return trajectory

High-resolution photofragment translational spectro- scopy for the UV photodissociation of C_2._5I

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Science china Chemistry 2007年第4期50卷 476-482页

作者： BI WeiBin, XU XiLing, HUANG JianGou, XIAO DaoQing & ZHU QiHe beijing National laboratory for Molecular Sciences, State Key laboratory of Molecular Reaction {3., Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 1. beijing National laboratory for Molecular Sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The photodissociation of ethyl iodide at 2.9.71, 2.1.73. 3.4.02.and 3.4.67 nm has been studied on our new mini-photofragment translational spectrometer with a total {3. path of only 5 cm. Some vibra-tional peaks are firstly resolved in the TOF spectra of I*(2.1/2. and I(2.3.2. channels. These vibrational peaks are assigned to the excitation states (ν2.= 0, 1, 2.…) of the umbrella mode (ν2. 540 cm-1) of the photofragment C2.5, and the distribution of the vibrational states is obtained. The dissociation energy has been determined to be D0(C-I)=2.3.4 ± 0.03.eV. The energy partitioning of the available energy (Eavl=ET+Eint=ET+EV,R) calculated from our experimental data E int /E avl= 2..1% at 2.1.73.nm, 2..4% at 3.4.02.nm for the I* channel, and E int /E avl= 2..2. at 2.9.71 nm, 2..9% at 3.4.67 nm for the I channel, seem to be more reliable.

关键词： photofragment translational spectroscopy C_2._5I photodissociation vibrational state distribution energy partitioning dissociation energy