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Prediction-based guidance algorithm for high-lift reentry vehicles

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science china(Information sciences) 2011年第3期54卷 498-510页

作者： ZHANG Zhao 1,2 & HU Jun 1 1 beijing Institute of control Engineering, beijing 100190, china 2 science and technology on space intelligent control laboratory, beijing 100190, china 1. beijing Institute of control Engineering Beijing 100190 China2. Science and Technology on Space Intelligent Control Laboratory Beijing 100190 China

In this work, we propose a pseudo four-degrees-of-freedom (DOF) prediction based guidance algo- rithm specifically for high-lift reentry vehicles. The algorithm is composed mainly of three parts. First, at the beginning of each guidance cycle, the 4-DOF predictor is called upon to predict the final downrange, crossrange, and heading errors. Then, the magnitude of the bank angle is determined from the downrange error, using the proportional-integral (PI) control method. Finally, two bank angle reversal time points are determined to minimize the crossrange and heading errors. Compared with traditional predictor-corrector guidance, the algorithm proposed does not require iterative procedures which significantly decreases the computational burden for the on-board computer and makes the implementation practical. Simulation results for dispersion tests demonstrated that our algorithm is computationally efficient and robust against uncertainties and disturbances.

关键词： pseudo 4-DOF prediction-based guidance high-lift reentry vehicle

On the placement of actuators and sensors for flexible structures with closely spaced modes

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science china(Technological sciences) 2010年第7期53卷 1973-1982页

作者： LIU XiaoXiang1,2 & HU Jun1,2 1 beijing Institute of control Engineering, beijing 100190, china 2 State Key laboratory of science and technology on space intelligent control, beijing 100190, china 1. beijing Institute of control Engineering Beijing 100190 China2. State Key Laboratory of Science and Technology on Space Intelligent Control Beijing 100190 China

This paper analyzed the fundamental limitations of previous work and developed a new method to optimally locate actuators and sensors for structures with close modes. Optimization criteria were defined based on the distinguishing modal controllability and observability measures of close modes. An appropriate genetic algorism was adopted as the optimization algorism. Solving the high order Lyapunov functions was avoided by means of the closed-form expressions for controllability and observability Grammians. Since structure with widely separated natural frequencies is approximately balanced, computational efficiency was improved by grouping close modes together and dealing with the resulting subsystems independently. Finally, the effectiveness and optimality of the novel placement scheme were verified on a model structure with close modes.

关键词： close modes controllability/observability sensor/actuator optimization criterion optimization algorithm

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Fuzzy dynamic characteristic model based attitude control of hypersonic vehicle in gliding phase

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science china(Information sciences) 2011年第3期54卷 448-459页

作者： LUO Xiong 1,2 & LI Jiang 1 1 Department of Computer science and technology, Key laboratory of Advanced control of Iron and Steel Process (Ministry of Education), University of science and technology beijing, beijing 100083, china 2 National laboratory of space intelligent control, beijing 100190, china 1. Department of Computer science and technology Key Laboratory of Advanced Control of Iron and Steel Process (Ministry of Education) University of Science and Technology Beijing Beijing 100083 China2. National Laboratory of Space Intelligent Control Beijing 100190 China

The intelligent autonomous control of hypersonic vehicles has aroused great interest from the field of spacecraft. To solve the problem of longitudinal attitude control of hypersonic vehicle in gliding phase, a new intelligent controller is proposed in this paper. This new controller is based on the fuzzy dynamic characteristic modeling method. The fuzzy logic is introduced into the characteristic modeling by dividing the whole restriction range into several subspaces. Simulations show that this modification greatly improves the performance of the original method. With the same whole restriction range the fuzzy dynamic characteristic modeling decreases the time of convergence, and at the same time makes the attitude angle tracing more precise and robust. Since the sub-model is a characteristic model that has stronger adaptiveness than a fixed local model, the number of fuzzy rules is greatly reduced. Our model sharply reduces the complexity in constructing a fuzzy dynamic model. Finally, simulation results are given to show the effectiveness of the proposed approach in dealing with the attitude control problem of hypersonic vehicle in gliding phase.

关键词： hypersonic vehicle gliding attitude control fuzzy dynamic characteristic modeling

On characteristic modeling of a class of flight vehicles'attitude dynamics

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science china(Technological sciences) 2010年第8期53卷 2074-2080页

作者： MENG Bin &WU HongXin National laboratory of space intelligent control,beijing Institute of control Engineering,beijing 100190,china 1. National laboratory of space intelligent control Beijing Institute of Control Engineering Beijing 100190 China

The characteristic modeling problem of flight vehicles'attitude dynamics is considered in this *** terms of the affine nonlinear system with triangle form of flight vehicles'attitude dynamics,a general method is presented to compress the dynamics into the characteristic model parameters,by introducing the time scale of nonlinear systems and a class of system states related compress *** parameter region and limit of the characteristic model are also *** the given parameter region it is seen that the bound of the characteristic model parameters is dependent on the sampling period,the modeling error,the system order and the system change *** modeling error of the established characteristic model can be arbitrarily small according to the control precision,showing the difference between the characteristic model and other model reduction methods,that is,no system information is lost using this *** the basis of this modeling approach,the characteristic model of the flexible satellite attitude is established,as well as the bound and limit of the parameters,which sets a theoretical foundation for characteristic model based control design of flight vehicles.

关键词： characteristic modeling modeling error time scale of nonlinear systems spacecraft attitude dynamics

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Tissue P systems with cell separation: attacking the partition problem

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science china(Information sciences) 2011年第2期54卷 293-304页

作者： ZHANG XingYi1, WANG Shuo2, NIU YunYun2 & PAN LinQiang2 1Key Lab of intelligent Computing and Signal Processing of Ministry of Education, School of Computer science and technology, Anhui University, Hefei 230039, china 2Image Processing and intelligent control Key laboratory of Education Ministry of china, Department of control science and Engineering, Huazhong University of science and technology, Wuhan 430074, china 1. Key Lab of intelligent Computing and Signal Processing of Ministry of Education School of Computer Science and Technology Anhui University Hefei 230039 China2. Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Tissue P systems are distributed parallel and non-deterministic computing models in the framework of membrane computing, which are inspired by intercellular communication and cooperation between neurons. Recently, cell separation is introduced into tissue P systems, which enables systems to generate an exponential workspace in a polynomial time. In this work, the computational power of tissue P systems with cell separation is investigated. Specifically, a uniform family of tissue P systems with cell separation is constructed for effciently solving a well-known NP-complete problem, the partition problem.

关键词： membrane computing tissue P system cell separation partition problem

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 flight 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 flight 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

NONPARAMETRIC APPROACH TO IDENTIFYING NARX SYSTEMS

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Journal of Systems science & Complexity 2010年第1期23卷 3-21页

作者： Qijiang SONG·Han-Pu CHEN Key laboratory of Systems and control,Institute of Systems science,Academy of Mathematics and Systems science,Chinese Academy of sciences,beijing 100190,china Key laboratory of Systems and control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper considers identification of the nonlinear autoregression with exogenous inputs(NARX system).The growth rate of the nonlinear function is required be not faster than linear withslope less than *** value of f(·) at any fixed point is recursively estimated by the stochasticapproximation (SA) algorithm with the help of kernel *** consistency of the estimatesis established under reasonable conditions,which,in particular,imply stability of the *** simulation is consistent with the theoretical analysis.

关键词： α-mixing geometrically ergodic Markov chains NARX nonparametric recursive estimate stochastic approximation strongly consistent.

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Sufficient and necessary conditions for Lyapunov stability of Lorenz system and their application

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science china(Information sciences) 2010年第8期53卷 1574-1583页

作者： LUO Qi 1 , LIAO XiaoXin 2 & ZENG ZhiGang 2 1 College of Information and control, Nanjing University of Information science and technology, Nanjing 210044, china 2 Department of control science and Engineering, Huazhong University of science and technology, Image Processing and intelligent control Key laboratory of Education Ministry of china, Wuhan 430074, china 1. College of Information and control Nanjing University of Information Science and Technology Nanjing 210044 China2. Department of Control Science and Engineering Huazhong University of Science and Technology Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Wuhan 430074 China

The sufficient and necessary conditions for Lyapunov stability of the zero equilibrium point of Lorenz system are discussed, and some brief criteria are presented for globally exponential stability, globally asymptotical stability and instability. Furthermore, the behavior of the non-zero equilibrium point of Lorenz system is also investigated, and several sufficient and necessary conditions are provided for locally exponential stability and instability. The established theorems in this paper develop and extend the existing achievements on Lyapunov stability of Lorenz system. In conclusion, by applying the obtained results, some less conservative feedback-control laws are derived to guarantee the globally exponential stability of the chaos control of Chen system, Lu¨ system, Yang-Chen system and Yu-Xia Li system.

关键词： Lorenz system Lyapunov stability sufficient and necessary condition bifurcation values globally exponential synchronization

A fast algorithm for color image enhancement with total variation regularization

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science china(Information sciences) 2010年第9期53卷 1913-1916页

作者： LI Ming1,2 1School of Computer science and technology,Huazhong University of science and technology,Wuhan 430074,china 2Key laboratory of Education Ministry for Image Processing and intelligent control,Wuhan 430074,china 1. School of Computer science and technology Huazhong University of Science and Technology Wuhan 430074 China2. Key Laboratory of Education Ministry for Image Processing and Intelligent Control Wuhan 430074 China

In this paper,a novel algorithm for color image enhancement is *** proposed method,which is based on Retinex theory and total variational framework,improves the original variational method by using a TV penalty term to force spatial smoothness on the reflectance *** split Bregman algorithm is employed to solve the proposed *** practical experiments,it is verified that our method obtains better enhancement performance and much better calculation efficiency.

关键词： color image enhancement Retinex theory total variational model split Bregman algorithm