The problem of fault-tolerant control is discussed for the longitudinal model of an airbreathing hypersonic vehicle (AHV) with actuator faults and external disturbances. Firstly, a fault-tolerant control strategy is...
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The problem of fault-tolerant control is discussed for the longitudinal model of an airbreathing hypersonic vehicle (AHV) with actuator faults and external disturbances. Firstly, a fault-tolerant control strategy is presented for the longitudinal model of an AHV, which guarantees that velocity and altitude track their reference trajectories at an exponential convergence rate. However, this method needs to know the minimum value of the actuator efficiency factor and the upper bound of the external disturbances, which makes it not easy to implement. Then an improved adaptive fault-tolerant control scheme is proposed, where two adaptive laws are employed to estimate the upper bound of the external disturbances and the minimum value of the actuator efficiency factor, respectively. Secondly, the problem of designing a control scheme with control constraints is further considered, and a new adaptive fault-tolerant control strategy with input saturation is designed to guarantee that velocity and altitude track their reference trajectories. Finally, simulation results are given to show the effectiveness of the proposed methods.
This work was supported by National Natural Science Foun- dation of China (Nos. 60905009, 61004032, 61104119, 61174076, and 61172135), and Jiangsu Province Natural Science Foundation (Nos. SBK201240801 and BK20123...
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This work was supported by National Natural Science Foun- dation of China (Nos. 60905009, 61004032, 61104119, 61174076, and 61172135), and Jiangsu Province Natural Science Foundation (Nos. SBK201240801 and BK2012384.)
In this paper, an adaptive approximation image reconstruction method based on orthogonal triangular with column pivoting (QRCP) decomposition algorithm is proposed for single sample problem in face recognition. By usi...
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In this paper, an adaptive approximation image reconstruction method based on orthogonal triangular with column pivoting (QRCP) decomposition algorithm is proposed for single sample problem in face recognition. By using QRCP the single sample and its transpose are decomposed to two sets of basis images. Then an adaptive approximation image reconstruction method is proposed to reconstruct two approximation images from the two basis image sets respectively. The single training sample and its two approximation images of each object form a new training set, which can make the fisher linear discriminant analysis (FLDA) be applied to single sample problem in face recognition. The performance of the proposed method is verified on Yale, FERET, and ORL face databases. The experimental results indicate that the proposed method is efficient and outperforms some existing methods which are proposed to overcome the single sample problem.
An on-demand weighed clustering algorithm is proposed against the limitation of wireless sensor network nodes with limited energy. This algorithm obtains more local network information by means of information interact...
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It is well known that vertical take-off and landing(VTOL) aircraft system is a complex multi-variable nonlinear system with large disturbances. In order to control the VTOL aircraft system ef ciently, it is necessary ...
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ISBN:
(纸本)9781479947249
It is well known that vertical take-off and landing(VTOL) aircraft system is a complex multi-variable nonlinear system with large disturbances. In order to control the VTOL aircraft system ef ciently, it is necessary to explore new optimal control methods to stabilize the system states. In this paper, we apply dual heuristic programming(DHP) to design the optimal controller for VTOL aircraft system. As a framework of approximate dynamic programming(ADP) algorithm, DHP consists of three modules: model, critic and actor. The critic module output partial derivatives of cost function with respect to state. It has many advantages such as good dynamics, fast convergence rate, and high control resolution. Simulation and experimental results demonstrate the effectiveness of optimal controller for VTOL aircraft system based on the DHP algorithm.
Dual-rotor axial field flux-switching permanent magnet (DRAFFSPM) machine is a novel permanent magnet (PM) machine which incorporates the merits of both the flux-switching PM machine and the axial field PM machine. Th...
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ISBN:
(纸本)9781479951635
Dual-rotor axial field flux-switching permanent magnet (DRAFFSPM) machine is a novel permanent magnet (PM) machine which incorporates the merits of both the flux-switching PM machine and the axial field PM machine. The cogging torque of the DRAFFSPM machine is high due to the flux focusing which is caused by the double salient structure. In order to reduce the cogging torque, the influence of the rotor pole width and shape on the cogging torque is analyzed based on the 3D finite element (FE) method. The cogging torque reduction methods, such as the rotor skewing, rotor notching, and rotor pole displacement, etc., are investigated. The results show that increasing the rotor pole width and adopting fan-shaped rotor pole can decrease the cogging torque greatly. The cogging torque can be reduced by ~77% when the rotor pole width and rotor fan-shaped angle are optimized to 15.5 deg. and 3 deg., respectively. The cogging torque can't be decreased by the rotor skewing for DRAFFSPM machine. However, the cogging torque can be reduced by rotor notching and rotor pole displacement.
In this paper, we show that Euler discretization of the sliding mode control system with twisting algorithm can lead to periodic behaviors. Bounds for periodic orbits are derived, which allow one to estimate the maxim...
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In this paper, we show that Euler discretization of the sliding mode control system with twisting algorithm can lead to periodic behaviors. Bounds for periodic orbits are derived, which allow one to estimate the maximum chattering amplitude for a given value of the time step. It is shown that for certain parameter values, there exist arbitrarily long periodic orbits. Theoretical results are illustrated with simulation examples.
This paper considers the problem of attitude synchronization for a group of flexible spacecraft based on distributed attitude cooperative control strategy. Based on the backstepping design, non-smooth control, and the...
This paper considers the problem of attitude synchronization for a group of flexible spacecraft based on distributed attitude cooperative control strategy. Based on the backstepping design, non-smooth control, and the neighbor-based design rule, a distributed attitude control law is constructed step by step. Under the proposed control law, it is shown that the attitude synchronization is achieved asymptotically and the induced vibration by flexible appendages is simultaneously suppressed.
With the rapid growth of Web services on the Internet, the atomic Web services as nodes and their functionality dependency relationships as edges form a complex Web service network. Various interactions between Web se...
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One crucial problem for a humanoid service robot is to be able to communicate with humans naturally. This study focuses on this issue and develops a social interactive system for a humanoid robot to interact with huma...
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