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Finite-time Sliding Mode Control Design for a Class of Uncertain Conic Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 809-816页

作者： Shuping He Jun Song school of electrical engineering and automation Anhui UniversityHefei 230601China

This paper studies the sliding mode controller design problems for a class of nonlinear system. The nonlinear function is considered to satisfy conic-type constraint condition. A novel finite-time boundedness(FTB) based sliding mode controller design theory is proposed. And then a sufficient condition is obtained in terms of linear matrix inequalities(LMIs), which guarantees the resulted sliding mode dynamics to be FTB wrt some predefined scalars. Thereafter, a FTB-based sliding mode control(SMC) law is synthesized to ensure the state of the controlled system is driven into a novel desired switching surface s(t) = c(c is a constant) in a finite time. Simulation results illustrate the validity of the proposed FTB-based SMC design theory.

关键词： Conic nonlinear system finite-time boundedness(FTB) sliding mode control(SMC) state-feedback

Differential System＇s Nonlinear Behaviour of Real Nonlinear Dynamical Systems

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Chinese Physics Letters 2007年第5期24卷 1170-1172页

作者：杨正瓴王渭巍尹振兴张军陈曦 school of electrical engineering and automation Tianjin University Tianjin 300072

Chaos attractor behaviour is usually preserved if the four basic arithmetic operations, i.e. addition, subtraction, multiplication, division, or their compound, are applied. First-order differential systems of one-dimensional real discrete dynamical systems and nonautonomous real continuous-time dynamical systems are also dynamical systems and their Lyapunov exponents are kept, if they are twice differentiable. These two conclusions are shown here by the definitions of dynamical system and Lyapunov exponent. Numerical simulations support our analytical results. The conclusions can apply to higher order differential systems if their corresponding order differentials exist.

关键词： CONTINUOUS-TIME ALGORITHM LYAPUNOV EXPONENTS CHAOTIC SYSTEMS MAPS RISE

Modeling for heterogeneous multi-stage information propagation networks and maximizing information

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Chinese Physics B 2019年第2期28卷 454-463页

作者： Ren-Jie Mei Li Ding Xu-Ming An Ping Hu school of electrical engineering and automation Wuhan UniversityWuhan 430072China

In this paper, we propose a heterogeneous multi-stage model to study the effect of social reinforcement on information propagation. Both heterogeneity of network components and the heterogeneity of individual reinforcement thresholds are considered. An information outbreak condition is derived, according to which the outbreak scale and individual density of each state under specific propagation parameters can be deduced. Monte Carlo experiments are conducted in Facebook networks to demonstrate the outbreak condition, and we find that social reinforcement effects generally inhibit the propagation of information though it contributes to the emergence of certain hot spots simultaneously. Additionally, by applying Pontryagin's Maximum Principle, we derive the optimal control strategy in the case of limited control resources to maximize the information propagation. Then the forward–backward sweep method is utilized to verify its performance with numerical simulation.

关键词： heterogeneous network social reinforcement multi-stage optimal resource allocation

Local Property of Recurrence Network for Investigating Gas-Liquid Two-Phase Flow Characteristics

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Chinese Physics Letters 2013年第5期30卷 18-21页

作者： ZHANG Xin-Wang JIN Ning-De GAO Zhong-Ke ZHAI Lu-Sheng school of electrical engineering and automation Tianjin UniversityTianjin 300072

Understanding the dynamics of gas-liquid two-phase flows is a challenge in the fields of nonlinear *** first construct and analyze a recurrence network from Chen's chaotic system and find that the network local statistic is feasible to characterize chaotic dynamics associated with unstable periodic *** we construct recurrence networks from gas-liquid two-phase flow experimental signals and associate the network topological statistic with the flow pattern *** results indicate that the recurrence network could be a powerful tool for the dynamic characterization of experimental gas-liquid two-phase flows.

关键词： dynamics chaotic statistic

Optimal Fixed-Point Tracking Control for Discrete-Time Nonlinear Systems via ADP

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 657-666页

作者： Ruizhuo Song Liao Zhu IEEE the school of automation and electrical engineering University of Science and Technology Beijing

Based on adaptive dynamic programming(ADP),the fixed-point tracking control problem is solved by a value iteration(VI) algorithm. First, a class of discrete-time(DT)nonlinear system with disturbance is considered. Second, the convergence of a VI algorithm is given. It is proven that the iterative cost function precisely converges to the optimal value,and the control input and disturbance input also converges to the optimal values. Third, a novel analysis pertaining to the range of the discount factor is presented, where the cost function serves as a Lyapunov function. Finally, neural networks(NNs) are employed to approximate the cost function, the control law, and the disturbance law. Simulation examples are given to illustrate the effective performance of the proposed method.

关键词： Adaptive dynamic programming (ADP) fixedpoint tracking optimal control

Multi-objective reentry trajectory optimization method via GVD for hypersonic vehicles

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Journal of Systems engineering and Electronics 2017年第4期28卷 732-744页

作者： Chaofang Hu Yue Xin Hao Feng school of electrical engineering and automation Tianjin University Tianjin 300072 China

In the constrained reentry trajectory design of hypersonic vehicles, multiple objectives with priorities bring about more difficulties to find the optimal solution. Therefore, a multi-objective reentry trajectory optimization (MORTO) approach via generalized varying domain (GVD) is proposed. Using the direct collocation approach, the trajectory optimization problem involving multiple objectives is discretized into a nonlinear multi-objective programming with priorities. In terms of fuzzy sets, the objectives are fuzzified into three types of fuzzy goals, and their constant tolerances are substituted by the varying domains. According to the principle that the objective with higher priority has higher satisfactory degree, the priority requirement is modeled as the order constraints of the varying domains. The corresponding two-side, single-side, and hybrid-side varying domain models are formulated for three fuzzy relations respectively. By regulating the parameter, the optimal reentry trajectory satisfying priorities can be achieved. Moreover, the performance about the parameter is analyzed, and the algorithm to find its specific value for maximum priority difference is proposed. The simulations demonstrate the effectiveness of the proposed method for hypersonic vehicles, and the comparisons with the traditional methods and sensitivity analysis are presented.

关键词： hypersonic vehicle reentry trajectory design multi-objective optimization generalized varying domain direct collocation method

PID Controller Optimization by GA and Its Performances on the Electro-hydraulic Servo Control System

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Chinese Journal of Aeronautics 2008年第4期21卷 378-384页

作者： Karam M. Elbayomy school of automation Science and electrical engineering Beijing University of Aeronautics and Astronautics

A proportional integral derivative （PID） controller is designed and attached to electro-hydraulic servo actuator system （EHSAS） to control the angular position of the rotary actuator which control the movable surface of space vehicles. The PID gain parameters are optimized by the genetic algorithm （GA）. The controller is verified on the new state-space model of servo-valves attached to the physical rotary actuator by SIMULINK program. The controller and the state-space model are verified experimentally. Simulation and experimental results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as compared with the classical PID controller and the compensator controller.

关键词： PID controller electro-hydraulic servo control system genetic controller GA

Multi-disciplinary design optimization with variable complexity modeling for a stratosphere airship

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Chinese Journal of Aeronautics 2019年第5期32卷 1244-1255页

作者： Shi YIN Ming ZHU Haoquan LIANG school of Aeronautic Science and engineering Beihang University school of automation Science and electrical engineering Beihang University

This paper proposes a hybrid architecture based on Multi-disciplinary Design Optimization(MDO) with the Variable Complexity Modeling(VCM) method, to solve the problem of general design optimization for a stratosphere airship. Firstly, MDO based on the Concurrent SubSpace Optimization(CSSO) strategy is improved for handling the subsystem coupling problem in stratosphere airship design which contains aerodynamics, structure, and energy. Secondly, the VCM method based on the surrogate model is presented for reducing the computational complexity in high-fidelity modeling without loss of accuracy. Moreover, the global-to-local optimization strategy is added to the architecture to enhance the process. Finally, the result gives a prominent stratosphere airship general solution that validates the feasibility and efficiency of the optimization architecture. Besides, a sensitivity analysis is conducted to outline the critical impact upon stratosphere airship design.

关键词： Multi-disciplinary design optimization Sensitivity analysis Stratosphere airship Surrogate model Variable complexity modeling

Optimization Based on Convergence Velocity and Reliability for Hydraulic Servo System

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Chinese Journal of Aeronautics 2009年第4期22卷 407-412页

作者： Muhammad Babar Nazir school of automation Science and electrical engineering Beijing University of Aeronautics and Astronautics

This article presents an optimal hybrid fuzzy proportion integral derivative （HFPID） controller based on combination of proportion integral derivative （PID） and fuzzy controllers, by which the parameters could be evaluated by global optimization either in convergence velocity or in convergence reliability. Focusing on the nonlinear factors of hydraulic servo system, this article takes advantage of PID and fuzzy logic controller integrated with scaling factors to acquire precise tracking performances. To further improve the performances, it provides new developed optimization with rapid convergence to attain reliable approach probability. Focusing on the performance indictors of evolutionary algorithm, this article presents a new technique to predict reliability of the optimization algorithm. Statistics authenticates the effectiveness and robustness of the optimization. Further, many simulation and experimental results indicate that the optimal HFPID could acquire perfect immunity against parametric uncertainties with external disturbance.

关键词： adaptive control system novel evolutionary algorithm hydraulic control equipment convergence velocity convergencereliability optimization