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A two-stage approach for managing actuators redundancy and its application to fault tolerant flight control

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Chinese Journal of Aeronautics 2015年第2期28卷 469-477页

作者： Zhong Lunlong Félix Mora-Camino Tianjin Key Laboratory for Advanced Signal and Image Processing Civil Aviation University of China Automation Research Group of MAIAA ENAC Toulouse University

In safety-critical systems such as transportation aircraft, redundancy of actuators is introduced to improve fault tolerance. How to make the best use of remaining actuators to allow the system to continue achieving a desired operation in the presence of some actuators failures is the main subject of this paper. Considering that many dynamical systems, including flight dynamics of a transportation aircraft, can be expressed as an input affine nonlinear system, a new state repre- sentation is adopted here where the output dynamics are related with virtual inputs associated with the intended operation. This representation, as well as the distribution matrix associated with the effectiveness of the remaining operational actuators, allows us to define different levels of fault tol- erant governability with respect to actuators＇ failures. Then, a two-stage control approach is devel- oped, leading frst to the inversion of the output dynamics to get nominal values for the virtual inputs and then to the solution of a linear quadratic （LQ） problem to compute the solicitation of each operational actuator. The proposed approach is applied to the control of a transportation air- craft which performs a stabilized roll maneuver while a partial failure appears. Two fault scenarios are considered and the resulting performance of the proposed approach is displayed and discussed.

关键词： Actuator allocation Fault tolerant control Flight control Linear quadratic (LQ)problem nonlinear control

Backstepping sliding mode control of a variable speed wind turbine for power optimization

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Journal of Modern Power Systems and Clean Energy 2015年第3期3卷 402-410页

作者： Saravanakumar RAJENDRAN Debashisha JENA National Institute of Technology Karnataka SurathkalIndia

To optimize the energy capture from the wind,wind turbine(WT)should operate at variable *** on the wind speed,the operating regions of the WT are divided into two parts:below and above the rated wind *** main aim at below rated wind speed is to maximize the energy capture from the wind with reduced oscillation on the drive *** above rated wind speed,the aim is to maintain the rated power by using pitch *** paper presents the control of WT at below rated wind speed by using backstepping sliding mode control(BSMC).In BSMC,generator torque is considered as the control input that depends on the optimal rotor ***,this optimal rotor speed is derived from effective wind *** this paper,effective wind speed is estimated from aerodynamic torque and rotor speed by using the modified Newton Rapshon(MNR)***,a conventional sliding mode controller(SMC)is applied to the WT,but the performance of the controller was found to be less robust with respect to ***,WT external disturbance is not *** overcome the above drawback,BSMC is proposed and both the controllers are tested with mathematical model and finally validated with the fatigue,aerodynamics,structures,and turbulence(FAST)WT simulator in the presence of *** the results,it is concluded that the proposed BSMC is more robust than conventional SMC in the presence of disturbances.

关键词： nonlinear control Single mass model Modified Newton Raphson(MNR) Backstepping sliding mode control(BSMC)

Formation keeping control through inter-satellite electromagnetic force

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Science China(Technological Sciences) 2013年第5期56卷 1102-1111页

作者： CAI WeiWei YANG LePing ZHU YanWei ZHANG YuanWen College of Aerospace Science and Engineering National University of Defense Technology

Satellite formation keeping through inter-satellite electromagnetic force provides an attractive alternative for future space missions due to its distinct advantages of no propellant consumption or plume contamination as compared to conventional ***,the internal force nature as well as the high nonlinearity and coupling of electromagnetic force brings new control challenges for this novel *** this paper,analysis on the dynamics characteristics and special control issues in the presence of electromagnetic force is carried out on the basis of the derived relatively translational *** the model uncertainties,external disturbances and sensor noise,a combined nonlinear control scheme involving feed-forward and feedback control components is proposed for electromagnetic-force-based formation *** feed-forward component is directly obtained through desired configuration and dynamics under nominal conditions while the feedback component is realized utilizing active disturbance rejection control methodology with some reasonable *** simulation is presented to verify the feasibility and validity of the combined control scheme.

关键词： inter-satellite electromagnetic force formation keeping dynamics analysis active disturbance rejection nonlinear control

Compliance motion control of the hydraulic dual-arm manipulator with adaptive mass estimation of unknown object

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Frontiers of Mechanical Engineering 2024年第1期19卷 35-52页

作者： Bolin SUN Min CHENG Ruqi DING Bing XU State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China Key Laboratory of Conveyance and Equipment(Ministry of Education) East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Given the limited operating ability of a single robotic arm,dual-arm collaborative operations have become increasingly *** with the electrically driven dual-arm manipulator,due to the unknown heavy load,difficulty in measuring contact forces,and control complexity during the closed-chain object transportation task,the hydraulic dual-arm manipulator(HDM)faces more difficulty in accurately tracking the desired motion trajectory,which may cause object deformation or even *** overcome this problem,a compliance motion control method is proposed in this paper for the *** mass parameter of the unknown object is obtained by using an adaptive method based on velocity *** to the difficulty in obtaining the actual internal force of the object,the pressure signal from the pressure sensor of the hydraulic system is used to estimate the contact force at the end-effector(EE)of two hydraulic manipulators(HMs).Further,the estimated contact force is used to calculate the actual internal force on the ***,a compliance motion controller is designed for HDM closed-chain *** position and internal force errors of the object are reduced by the feedback of the position,velocity,and internal force errors of the object to achieve the effect of the compliance motion of the HDM,i.e.,to reduce the motion error and internal force of the *** required velocity and force at the EE of the two HMs,including the position and internal force errors of the object,are inputted into separate position *** addition,the position controllers of the two individual HMs are designed to enable precise motion control by using the virtual decomposition control ***,comparative experiments are carried out on a hydraulic dual-arm test *** proposed method is validated by the experimental results,which demonstrate improved object position accuracy and reduced internal force.

关键词： hydraulic dual-arm manipulator compliance motion control unknown object adaptive mass estimation nonlinear control

General Convex Integral control

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International Journal of Automation and computing 2014年第5期11卷 565-570页

作者： Bai-Shun Liu Xiang-Qian Luo Jian-Hui Li Academy of Naval Submarine

In this paper, a fire-new general integral control, named general convex integral control, is proposed. It is derived by defining a nonlinear function set to form the integral control action and educe a new convex function gain integrator, introducing the partial derivative of Lyapunov function into the integrator and resorting to a general strategy to transform ordinary control into general integral control. By using Lyapunov method along with the LaSalle s invariance principle, the theorem to ensure regionally as well as semi-globally asymptotic stability is established only by some bounded information. Moreover, the lemma to ensure the integrator output to be bounded in the time domain is proposed. The highlight point of this integral control strategy is that the integral control action seems to be infinity, but it factually is finite in the time domain. Therefore, a simple and ingenious method to design the general integral control is founded. Simulation results showed that under the normal and perturbed cases, the optimum response in the whole control domain of interest can all be achieved by a set of control gains, even under the case that the payload is changed abruptly.

关键词： General integral control nonlinear integrator convex integrator nonlinear control output regulation

Global Null controllability of the 1-Dimensional nonlinear Slow Diffusion Equation

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Chinese Annals of Mathematics,Series B 2013年第3期34卷 333-344页

作者： Jean-Michel CORON Jesǘs Ildefonso DIAZ Abdelmalek DRICI Tommaso MINGAZZINI Institut Universitaire de France and Universit Pierre et Marie Curie (Paris 6) UMR 7598 Laboratoire Jacques-Louis Lions 4 place Jussieu F-75252 Paris cedex 5 France Universidad Complutense de Madrid Instituto de Matemtica Interdisiplinar and Dpto. de Matemtica Aplicada Plaza de las Ciencias 3 28040 Madrid Espaa Universit Pierre et Marie Curie (Paris 6) UMR 7598 Laboratoire Jacques-Louis Lions 4 place Jussieu F-75252 Paris cedex 5 France Universidad Complutense de Madrid Dpto. de Matemtica Aplicada Plaza de las Ciencias 3 28040 Madrid Espaa

The authors prove the global null controllability for the 1-dimensional nonlinear slow diffusion equation by using both a boundary and an internal control. They assume that the internal control is only time dependent. The proof relies on the return method in combination with some local controllability results for nondegenerate equations and rescaling techniques.

关键词： nonlinear control nonlinear slow diffusion equation Porous mediumequation

An Adaptive Identification and control SchemeUsing Radial Basis Function Networks

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Journal of Systems Engineering and Electronics 1999年第1期10卷 54-61页

作者： Chen Zengqiang He Jiangfeng Yuan Zhuzhi (Department of Computer and System Science, Nankai University, Tianjin 300071, P. R. China)(Received July 12, 1998) Department of Computer and System Science Nankai University Tianjin 300071 P. R. China

In this paper, adaptive identification and control of nonlinear dynamical systems are investigated using radial basis function networks (RBF). Firstly, a novel approach to train the RBF is introduced, which employs an adaptive fuzzy generalized learning vector quantization (AFGLVQ) technique and recursive least squares algorithm with variable forgetting factor (VRLS). The AFGLVQ adjusts the centers of the RBF while the VRLS updates the connection weights of the network. The identification algorithm has the properties of rapid convergence and persistent adaptability that make it suitable for real-time control. Secondly, on the basis of the one-step ahead RBF predictor, the control law is optimized iteratively through a numerical stable Davidon's least squares-based (SDLS) minimization approach. Four nonlinear examples are simulated to demonstrate the effectiveness of the identification and control algorithms.

关键词： Neural networks Adaptive control nonlinear control Radial basis function networks Recursive least squares.

Global robust output regulation of lower triangular systems with nonlinear exosystems and its application

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控制理论与应用（英文版） 2013年第3期11卷 468-476页

作者： Weijie SUN College of Automation Science and Engineering South China University of Technology

This paper studies the global robust output regulation problem for lower triangular systems subject to nonlinear exosystems. By employing the internal model approach, this problem can be boiled down to a global robust stabilization problem of a time-varying nonlinear system in the cascade-connected form. Then, a set of sufficient conditions for the solvability of the problem is derived, and thus, leading to the solution to the global robust output regulation problem. An application of the main result of this paper is also proposed.

关键词： nonlinear control Internal model Lyapunov method Dissipative Robust stabilization

control of chaotic oscillations of a satellite

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Applied Mathematics and Mechanics(English Edition) 2007年第7期28卷 893-900页

作者： Alexey Bobtsov Nikolay Nikolaev Olga Slita Department of control Systems and Informatics Saint-Petersburg State University of Information Technologies Mechanics and OpticsKronverksky Ave.49Saint-Petersburg197101Russia

Analytical conditions and practical methods of their realization are proposed to solve a problem of a command signal tracking for a nonlinear disturbed system. nonlinear disturbed plants consisting of linear dynamic block and nonlinear block in feedback are considered. nonlinear part of the plant and disturbance are unknown and bounded. The paper illustrates a possibility of applications of proposed algorithms to control libration angle of satellite.

关键词： adaptive control chaotic behaviour satellite control nonlinear stabilization nonlinear control output control