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Gang Tao - One of the best experts on this subject based on the ideXlab platform.

  • Adaptive Actuator Failure Compensation Control Schemes for Uncertain Noncanonical Neural-Network Systems.
    IEEE transactions on cybernetics, 2020
    Co-Authors: Guanyu Lai, Gang Tao, Yun Zhang, Zhi Liu, Junwei Wang
    Abstract:

    In this article, direct adaptive Actuator Failure compensation control is investigated for a class of noncanonical neural-network nonlinear systems whose relative degrees are implicit and parameters are unknown. Both the state tracking and output tracking control problems are considered, and their adaptive solutions are developed which have specific mechanisms to accommodate both Actuator Failures and parameter uncertainties to ensure the closed-loop system stability and asymptotic state or output tracking. The adaptive Actuator Failure compensation control schemes are derived for noncanonical nonlinear systems with neural-network approximation, and are also applicable to general parametrizable noncanonical nonlinear systems with both unknown Actuator Failures and unknown parameters, solving some key technical issues, in particular, dealing with the system zero dynamics under uncertain Actuator Failures. The effectiveness of the developed adaptive control schemes is confirmed by simulation results from an application example of speed control of dc motors.

  • ASCC - Adaptive Actuator Failure Compensation for Multivariable Systems Using A Multiple-Model Design *
    2019
    Co-Authors: Chang Tan, Gang Tao, Hui Yang, Lu Rongxiu
    Abstract:

    This paper develops a new adaptive compensation control scheme for multivariable systems with some unknown Actuator Failures, based on a multiple-model approach. Such a scheme can handle possible structure changes from Actuator Failures and uncertain parameter changes of multivariable systems. Multiple parametrizations are employed for the system under different Actuator Failure patterns, each for design of an adaptive compensation control signal for individual pattern. Performance indexes are formed based on normalized estimation errors for all Failure patterns and the control signal with best performance is decided to control the system. Such an adaptive multiple-mode design has the potential of fast Failure compensation an uncertainty adaptation. A complete design procedure is presented, with clarification and analysis of some key system properties. Simulation results are used to demonstrate the effectiveness of the designed adaptive Failure compensation control scheme.

  • adaptive Actuator Failure compensation for multivariable systems using a multiple model design
    Asian Control Conference, 2019
    Co-Authors: Chang Tan, Gang Tao, Hui Yang
    Abstract:

    This paper develops a new adaptive compensation control scheme for multivariable systems with some unknown Actuator Failures, based on a multiple-model approach. Such a scheme can handle possible structure changes from Actuator Failures and uncertain parameter changes of multivariable systems. Multiple parametrizations are employed for the system under different Actuator Failure patterns, each for design of an adaptive compensation control signal for individual pattern. Performance indexes are formed based on normalized estimation errors for all Failure patterns and the control signal with best performance is decided to control the system. Such an adaptive multiple-mode design has the potential of fast Failure compensation an uncertainty adaptation. A complete design procedure is presented, with clarification and analysis of some key system properties. Simulation results are used to demonstrate the effectiveness of the designed adaptive Failure compensation control scheme.

  • adaptive Actuator Failure compensation for possibly nonminimum phase systems using control separation based lq design
    IEEE Transactions on Automatic Control, 2019
    Co-Authors: Liyan Wen, Gang Tao, Hao Yang, Bin Jiang
    Abstract:

    This paper develops an adaptive Actuator Failure compensation control scheme for discrete-time and possibly nonminimum-phase systems with unknown Actuator Failures of characterizations that first, some unknown system inputs are stuck at some unknown fixed or varying values at unknown time instants, and second, the Actuator Failures as system disturbances are not matched by other inputs. Such a Failure compensation control problem is solved by using a new control separation design based on a new linear quadratic (LQ) control formulation: One control component is used for disturbance rejection and Actuator Failure compensation, and one component is used for closed-loop stability and regulation, to achieve the desired control objective. The nominal LQ control solution uses a new cost function to derive the two-component control signal, which has improved performance over a traditional LQ control design. The adaptive Actuator Failure compensation control problem is solved using a stable adaptive law for parameter estimation, to guarantee the system stability and output regulation performances in the presence of plant and Actuator Failure uncertainties. Simulation results are presented to verify the satisfactory performance of the proposed adaptive LQ control scheme.

  • An Adaptive Actuator Failure Compensation Scheme for A Hexarotor System with Parameter Uncertainties
    2018 International Conference on Unmanned Aircraft Systems (ICUAS), 2018
    Co-Authors: Yu Sheng, Gang Tao, Peter A. Beling
    Abstract:

    In this paper, an adaptive control design is developed for hexarotor systems subject to uncertain parameters and unknown Actuator Failures. The developed control scheme consists of a control signal distributor and a state feedback controller equipped with adaptive laws. It is verified that the control distribution matrix ensures that under different uncertain Actuator Failure patterns the controlled system has high frequency gain matrices whose equivalent signs are invariant. A nominal control scheme is first constructed for the case of known parameters and Failures, to demonstrate the existence of the plant and reference model matching parameters. A multivariable model reference adaptive controller is developed to deal with system and Failure uncertainties, using an LDS gain matrix decomposition based parametrization for the derivation of the estimation error and adaptive law. Such a control design effectively utilizes the controller adaptation and system actuation redundancy to compensate for possible uncertain Actuator Failures in the presence of system uncertainties. Simulation results are presented to verify the desired performance of the adaptive compensation scheme developed for hexarotor systems.

S M Joshi - One of the best experts on this subject based on the ideXlab platform.

  • adaptive Actuator Failure compensation for nonlinear mimo systems with an aircraft control application
    Automatica, 2007
    Co-Authors: Xidong Tang, S M Joshi
    Abstract:

    A direct adaptive approach is developed for control of a class of multi-input multi-output (MIMO) nonlinear systems in the presence of uncertain Failures of redundant Actuators. An adaptive Failure compensation controller is designed which is capable of accommodating uncertainties in Actuator Failure time instants, values and patterns. A realistic situation is studied with fixed grouping of Actuators and proportional actuation within Actuator groups. The adaptive control system is analyzed, to show its desired stability and asymptotic tracking properties in the presence of Actuator Failure uncertainties. As an application, such an adaptive controller is used for Actuator Failure compensation of a twin otter aircraft longitudinal model, with design conditions verified and control structure and adaptive laws developed for a nonlinear aircraft dynamic model. The effectiveness of adaptive Failure compensation is demonstrated by simulation results.

  • Adaptive output feedback Actuator Failure compensation for a class of non-linear systems
    International Journal of Adaptive Control and Signal Processing, 2005
    Co-Authors: Xidong Tang, Gang Tao, S M Joshi
    Abstract:

    An adaptive compensation control scheme using output feedback is designed and analysed for a class of non-linear systems with state-dependent non-linearities in the presence of unknown Actuator Failures. For a linearly parameterized model of Actuator Failures with unknown Failure values, time instants and pattern, a robust backstepping-based adaptive non-linear controller is employed to handle the system Failure, parameter and dynamics uncertainties. Robust adaptive parameter update laws are derived to ensure closed-loop signal boundedness and small tracking errors, in general, and asymptotic regulation, in particular. An application to controlling the angle of attack of a non-linear hypersonic aircraft dynamic model in the presence of elevator segment Failures is studied and simulation results show that the developed adaptive control scheme has desired Actuator Failure compensation performance. Copyright © 2004 John Wiley & Sons, Ltd.

  • adaptive Actuator Failure compensation control for mimo systems
    International Journal of Control, 2004
    Co-Authors: Shuhao Chen, Gang Tao, S M Joshi
    Abstract:

    Two adaptive Failure compensation control schemes based on MRAC are developed for a class of MIMO LTI systems with unknown Actuator Failures. An effective controller structure is proposed to achieve the desired plant-model output matching when implemented with matching parameters. Design conditions are specified for such nominal plant-model output matching. Two adaptive versions of the nominal controller are proposed and stable adaptive laws are derived for updating the controller parameters when plant parameters and Failure parameters are unknown. All closed-loop signals are bounded and the plant outputs track the given reference outputs asymptotically, despite the uncertainties in Actuator Failures and plant parameters. Simulation results for an aircraft lateral dynamic model verify the desired adaptive control system performance in the presence of unknown rudder and aileron Failures.

  • adaptive Actuator Failure compensation designs for linear systems
    International Journal of Control Automation and Systems, 2004
    Co-Authors: Shuhao Chen, Gang Tao, S M Joshi
    Abstract:

    This paper surveys some existing direct adaptive feedback control schemes for lin- ear time-invariant systems with Actuator Failures characterized by the Failure pattern that some inputs are stuck at some unknown fixed or varying values at unknown time instants, and ap- plications of those schemes to aircraft flight control system models. Controller structures, plant-model matching conditions, and adaptive laws to update controller parameters are inves- tigated for the following cases for continuous-time systems: state tracking using state feed- back, output tracking using state feedback, and output tracking using output feedback. In ad- dition, a discrete-time output tracking design using output feedback is presented. Robustness of this design with respect to unmodeled dynamics and disturbances is addressed using a modified robust adaptive law.

  • Brief Adaptive Actuator Failure compensation for parametric strict feedback systems and an aircraft application
    Automatica, 2003
    Co-Authors: Xidong Tang, Gang Tao, S M Joshi
    Abstract:

    Adaptive Actuator Failure compensation for parametric-strict-feedback systems is studied under different system structure conditions. Adaptive state feedback control schemes are developed, which ensure asymptotic output tracking and closed-loop signal boundedness. An adaptive control scheme is applied to a twin otter aircraft longitudinal nonlinear dynamics model in the presence of unknown Failures in a two-segment elevator servomechanism. Simulation results verify the effectiveness of adaptive Actuator Failure compensation for desired system performance.

Xidong Tang - One of the best experts on this subject based on the ideXlab platform.

  • adaptive Actuator Failure compensation for nonlinear mimo systems with an aircraft control application
    Automatica, 2007
    Co-Authors: Xidong Tang, S M Joshi
    Abstract:

    A direct adaptive approach is developed for control of a class of multi-input multi-output (MIMO) nonlinear systems in the presence of uncertain Failures of redundant Actuators. An adaptive Failure compensation controller is designed which is capable of accommodating uncertainties in Actuator Failure time instants, values and patterns. A realistic situation is studied with fixed grouping of Actuators and proportional actuation within Actuator groups. The adaptive control system is analyzed, to show its desired stability and asymptotic tracking properties in the presence of Actuator Failure uncertainties. As an application, such an adaptive controller is used for Actuator Failure compensation of a twin otter aircraft longitudinal model, with design conditions verified and control structure and adaptive laws developed for a nonlinear aircraft dynamic model. The effectiveness of adaptive Failure compensation is demonstrated by simulation results.

  • Adaptive output feedback Actuator Failure compensation for a class of non-linear systems
    International Journal of Adaptive Control and Signal Processing, 2005
    Co-Authors: Xidong Tang, Gang Tao, S M Joshi
    Abstract:

    An adaptive compensation control scheme using output feedback is designed and analysed for a class of non-linear systems with state-dependent non-linearities in the presence of unknown Actuator Failures. For a linearly parameterized model of Actuator Failures with unknown Failure values, time instants and pattern, a robust backstepping-based adaptive non-linear controller is employed to handle the system Failure, parameter and dynamics uncertainties. Robust adaptive parameter update laws are derived to ensure closed-loop signal boundedness and small tracking errors, in general, and asymptotic regulation, in particular. An application to controlling the angle of attack of a non-linear hypersonic aircraft dynamic model in the presence of elevator segment Failures is studied and simulation results show that the developed adaptive control scheme has desired Actuator Failure compensation performance. Copyright © 2004 John Wiley & Sons, Ltd.

  • robust and adaptive Actuator Failure compensation designs for a rocket fairing structural acoustic model
    IEEE Transactions on Aerospace and Electronic Systems, 2004
    Co-Authors: Xidong Tang, Gang Tao, Lingfeng Wang, John A. Stankovic
    Abstract:

    The Actuator Failure compensation problem is formulated for active vibration control of a rocket fairing structural-acoustic model with unknown Actuator Failures. Performance of a nominal optimal control scheme in the presence of Actuator Failures is studied to show the need of effective Failure compensation. A robust control scheme and two adaptive control schemes are developed, which are able to ensure the closed-loop system signal boundedness in the presence of Actuator Failures whose Failure pattern and values are unknown. The adaptive scheme for parameterizable Failures ensures asymptotic stability despite Failure uncertainties. Simulation results verified their Failure compensation effectiveness.

  • Adaptive Actuator Failure compensation for cooperating multiple manipulator systems
    IFAC Proceedings Volumes, 2003
    Co-Authors: E. Faruk Kececi, Xidong Tang, Gang Tho
    Abstract:

    Abstract This paper presents adaptive Actuator Failure compensation for a cooperating multiple manipulator system with uncertain Actuator Failures in the task space. Advantages of designing control schemes in task spaces are emphasized, applications of task space control in robotics are discussed and a short review on control algorithms for cooperating multiple manipulator systems is given. Dynamic equations of motion of the multiple manipulator system in the task space are derived, and the adaptive Actuator Failure compensation problem is formulated. A compensation controller structure is proposed, for which adaptive parameter update laws are developed. The adaptive control scheme is able to compensate for the uncertainties arising from both the system parameters and the Actuator Failures. Based on Lyapunov stability analysis, the closed-loop signal boundedness and the convergence of the tracking error to zero are ensured.

  • Actuator Failure compensation schemes for vibration control of a rocket fairing model
    IFAC Proceedings Volumes, 2003
    Co-Authors: Lingfeng Wang, Gang Tao, Xidong Tang, John A. Stankovic
    Abstract:

    Abstract In this paper, the Actuator Failure compensation problem is formulated for active vibration control of a launch vehicle payload fairing. Performance of a nominal optimal control scheme for active vibration control is analyzed in light of a typical Actuator Failure model that certain Actuator outputs are stuck at unknown fixed values at unknown time instants. Three stabilizing control schemes handling uncertain Actuator Failures are developed to ensure closed-loop system signal boundedness in the presence of uncertain Actuator Failures. Simulation results are presented to demonstrate their effectiveness.

Bin Jiang - One of the best experts on this subject based on the ideXlab platform.

  • adaptive Actuator Failure compensation for possibly nonminimum phase systems using control separation based lq design
    IEEE Transactions on Automatic Control, 2019
    Co-Authors: Liyan Wen, Gang Tao, Hao Yang, Bin Jiang
    Abstract:

    This paper develops an adaptive Actuator Failure compensation control scheme for discrete-time and possibly nonminimum-phase systems with unknown Actuator Failures of characterizations that first, some unknown system inputs are stuck at some unknown fixed or varying values at unknown time instants, and second, the Actuator Failures as system disturbances are not matched by other inputs. Such a Failure compensation control problem is solved by using a new control separation design based on a new linear quadratic (LQ) control formulation: One control component is used for disturbance rejection and Actuator Failure compensation, and one component is used for closed-loop stability and regulation, to achieve the desired control objective. The nominal LQ control solution uses a new cost function to derive the two-component control signal, which has improved performance over a traditional LQ control design. The adaptive Actuator Failure compensation control problem is solved using a stable adaptive law for parameter estimation, to guarantee the system stability and output regulation performances in the presence of plant and Actuator Failure uncertainties. Simulation results are presented to verify the satisfactory performance of the proposed adaptive LQ control scheme.

  • Multidesign Integration Based Adaptive Actuator Failure Compensation Control for Two Linked 2WD Mobile Robots
    IEEE ASME Transactions on Mechatronics, 2017
    Co-Authors: Vincent Cocquempot, Maan El Badaoui El Najjar, Bin Jiang
    Abstract:

    This paper develops an Actuator Failure compensation control scheme for two linked mobile robots. The kinematic and dynamic models of two robots with a physical link that is employed to deal with Actuator Failures for two-wheel drive mobile robots are proposed. Then, a kinematic controller is designed, which is a virtual one. Based on this controller, multiple adaptive dynamic control signals are designed to cover all possible Failure cases. By combining these dynamic control signals, the dynamic controller is designed, which ensures desired system stability and asymptotic tracking properties. Finally, simulation results verify the effectiveness of the proposed adaptive Actuator Failure compensation scheme.

  • Adaptive Compensation of Traction System Actuator Failures for High-Speed Trains
    IEEE Transactions on Intelligent Transportation Systems, 2017
    Co-Authors: Zehui Mao, Gang Tao, Bin Jiang, Xing-gang Yan
    Abstract:

    In this paper, an adaptive Failure compensation problem is addressed for high-speed trains with longitudinal dynamics and traction system Actuator Failures. Considered the time-varying parameters of the train motion dynamics caused by time-varying friction characteristics, a new piecewise constant model is introduced to describe the longitudinal dynamics with variable parameters. For both the healthy piecewise constant system and the system with Actuator Failures, the adaptive controller structure and conditions are derived to achieve the plant-model matching. The adaptive laws are designed to update the adaptive controller parameters, in the presence of the system piecewise constant parameters and Actuator Failure parameters which are unknown. Based on Lyapunov functions, the closed-loop stability and asymptotic state tracking are proved. Simulation results on a high-speed train model are presented to illustrate the performance of the developed adaptive Actuator Failure compensation control scheme.

  • adaptive Actuator Failure identification for microsatellites under closed loop control
    IEEE Transactions on Control Systems and Technology, 2015
    Co-Authors: Bin Jiang, Gang Tao
    Abstract:

    This paper addresses the Actuator Failure identification problem of microsatellites in a stabilized feedback framework. An adaptive Failure identification scheme is developed using multiple estimators and cost functions to identify the failed Actuators for understanding vehicle health and protecting microsatellites. For the implementation of Failure identification, an adaptive Failure compensation scheme is developed using an uncertainty decomposition to guarantee the system stability and asymptotic tracking properties, and a special reference motion is also provided using a linearly independent condition. After some Actuators have failed, both identification and control are applied, and the control, while stabilizing the system, makes the microsatellite engage in the provided special motion so that the failed Actuators can be identified by the identification algorithm. Simulation results illustrate the effectiveness of the proposed adaptive Failure identification and compensation schemes.

  • Adaptive Actuator Failure compensation for multivariable feedback linearizable systems
    International Journal of Robust and Nonlinear Control, 2015
    Co-Authors: Xuelian Yao, Gang Tao, Bin Jiang
    Abstract:

    Summary A feedback linearization-based adaptive control scheme is developed for multivariable nonlinear systems with redundant Actuators subject to uncertain Failures. Such an adaptive controller contains a direct adaptive Actuator Failure compensator to compensate the uncertain Actuator Failure, a nonlinear feedback to linearize the nonlinear dynamics, and a linear feedback to stabilize the linearized system. The key new design feature is the estimation of both the Failure patterns and the Failure values, for direct adaptive Actuator Failure compensation, newly developed for multivariable feedback linearizable nonlinear systems. With direct control signal adaptation, the adaptive Failure compensation design ensures closed-loop stability and asymptotic output tracking in the presence of Actuator Failure uncertainties. Simulation results from an application to attitude control of a near-space vehicle dynamic model are presented to verify the desired system performance with adaptive Actuator Failure compensation. Copyright © 2015 John Wiley & Sons, Ltd.

Jafar Ghaisari - One of the best experts on this subject based on the ideXlab platform.

  • Adaptive control of uncertain nonlinear time delay systems in the presence of Actuator Failures and applications to chemical reactor systems
    European Journal of Control, 2016
    Co-Authors: Mahnaz Hashemi, Javad Askari, Jafar Ghaisari
    Abstract:

    Abstract This paper presents an adaptive Actuator Failure compensation scheme for a class of uncertain nonlinear systems with unknown nonlinearities, unknown time varying delays and in the presence of time varying Actuator Failures. The considered Actuator Failure is modeled to cover both loss of effectiveness and stuck at some time varying values where the values, times and patterns of the Failures are unknown. With the help of Neural Networks to approximate the unknown nonlinear functions, a novel adaptive Actuator Failure compensation controller is developed based on the backstepping design method. The appropriate Lyapunov–Krasovskii functionals are introduced to design new adaptive laws to compensate the unknown time varying Actuator Failures as well as uncertainties from unknown nonlinearities and time varying delays. The proposed design method does not require a priori knowledge of the bounds of the unknown time delays and Actuator Failures. The boundedness of all the closed-loop signals is guaranteed and the tracking error is proved to converge to a small neighborhood of the origin. Finally, the developed approach is applied to the control design of a chemical reactor with delayed recycle streams. The simulation results are provided to show the effectiveness of the proposed approach.

  • Adaptive compensation for Actuator Failure in a class of non-linear time-delay systems
    IET Control Theory & Applications, 2015
    Co-Authors: Mahnaz Hashemi, Javad Askari, Jafar Ghaisari, Marzieh Kamali
    Abstract:

    This study presents a state feedback adaptive controller for a class of parametric-strict-feedback non-linear systems with multiple bounded time-varying state delays and in the presence of time-varying Actuator Failures. The type of the considered Actuator Failure is that some unknown inputs may be stuck at some unknown time-varying values where the parameters, times and patterns of the Failures are also unknown. The considered Actuator Failure can cover most Failures that may occur in Actuators of the systems. The adaptive state feedback control scheme is constructed based on a backstepping design method. The boundedness of all the closed-loop signals is guaranteed and the tracking error is proved to converge to a small neighbourhood of the origin. The proposed approach is employed for a second-order time delay plant as well as a two-stage chemical reactor with delayed recycle streams. The simulation results show the correctness and effectiveness of the proposed adaptive compensation in the case of Actuator Failures.

  • adaptive Actuator Failure compensation for a class of mimo nonlinear time delay systems
    Nonlinear Dynamics, 2015
    Co-Authors: Mahnaz Hashemi, Javad Askari, Jafar Ghaisari
    Abstract:

    In this paper, an adaptive Actuator Failure compensation scheme is proposed for a class of parametric-strict-feedback multi- input multi-output nonlinear systems with unknown time- varying state delays. The considered Actuator Failures are types of loss of effectiveness, in which unknown system inputs may lose unknown fraction of their effectiveness. The adaptive compensation controller is constructed by utilizing a backstepping design method. The appropriate Lyapunov–Krasovskii functionals are introduced to design new adaptive laws to compensate the unknown Actuator Failures as well as uncertainties from unknown parameters and state delays. The boundedness of all the closed-loop signals is guaranteed, and the tracking errors are proved to converge to a small neighborhood of the origin. Simulation results are provided to show the effectiveness of the proposed approach.