robust control

摘要： This article proposes a novel method for maintaining the trajectory of an aerial manipulator by utilizing a fast nonsingular terminal sliding mode(FNTSM)manifold and a linear extended state observer(LESO).The developed controlmethod applies an FNTSMto ensure the tracking performance’s control accuracy,and an LESO to estimate the system’s unmodeled dynamics and external disturbances.Additionally,an improved salp swarm algorithm(ISSA)is employed to parameter tune the suggested controller by integrating the salp swarmtechnique with a cloud model.This approach also uses a model-free scheme to reduce the complexity of controller design without relying on complex and precise dynamics models.The simulation results show that the proposed controller outperforms linear active rejection disturbance control and PID controllers in terms of transient performance and resilience against lumped disturbances,and the ISSA can help the proposed controller find optimal control parameters.

摘要： The Ball and beam system(BBS)is an attractive laboratory experimental tool because of its inherent nonlinear and open-loop unstable properties.Designing an effective ball and beam system controller is a real challenge for researchers and engineers.In this paper,the control design technique is investigated by using Intelligent Dynamic Inversion(IDI)method for this nonlinear and unstable system.The proposed control law is an enhanced version of conventional Dynamic Inversion control incorporating an intelligent control element in it.The Moore-PenroseGeneralized Inverse(MPGI)is used to invert the prescribed constraint dynamics to realize the baseline control law.A sliding mode-based intelligent control element is further augmented with the baseline control to enhance the robustness against uncertainties,nonlinearities,and external disturbances.The semi-global asymptotic stability of IDI control is guaranteed in the sense of Lyapunov.Numerical simulations and laboratory experiments are carried out on this ball and beam physical system to analyze the effectiveness of the controller.In addition to that,comparative analysis of RGDI control with classical Linear Quadratic Regulator and Fractional Order Controller are also presented on the experimental test bench.

摘要： A linear flexible joint system using fractional order linear active disturbance rejection control is studied in this paper.With this control scheme,the performance against disturbances,uncertainties,and attenuation is enhanced.Linear active disturbance rejection control(LADRC)is mainly based on an extended state observer(ESO)technology.A fractional integral(FOI)action is combined with the LADRC technique which proposes a hybrid control scheme like FO-LADRC.Incorporating this FOI action improves the robustness of the standard LADRC.The set-point tracking of the proposed FO-LADRC scheme is designed by Bode’s ideal transfer function(BITF)based robust closed-loop concept,an appropriate pole placement method.The effectiveness of the proposed FO-LADRC scheme is illustrated through experimental results on the linear flexible joint system(LFJS).The results show the enhancement of the robustness with disturbance rejection.Furthermore,a comparative analysis is presented with the results obtained using the integer-order LADRC and FO-LADRC scheme.

摘要： This paper presents the design of a robust control system for a high-purity distillation column. It is concerned with the design of a two degree-of-freedom (2DOF) product-composition controller for a high-purity distillation column. The H∞ optimization problem is set up to ensure a guaranteed level of robust stability, robust disturbance attenuation and robust reference tracking performance.

摘要： This paper describes a system designed for linear servo cart systems that employs an integral-based Linear Active Disturbance Rejection Control(ILADRC)scheme to detect and respond to disturbances.The upgrade in this control technique provides extensive immunity to uncertainties,attenuation,internal disturbances,and external sources of noise.The fundamental technology base of LADRC is Extended State Observer(ESO).LADRC,when combined with Integral action,becomes a hybrid control technique,namely ILADRC.Setpoint tracking is based on Bode’s Ideal Transfer Function(BITF)in this proposed ILADRC technique.This proves to be a very robust and appropriate pole placement scheme.The proposed LSC system has experimented with the hybrid ILADRC technique plotted the results.From the results,it is evident that the proposed ILADRC scheme enhances the robustness of the LSC system with remarkable disturbance rejection.Furthermore,the results of a linear quadratic regulator(LQR)and ILADRC schemes are comparatively analyzed.This analysis deduced the improved performance of ILADRC over the LQR control scheme.

摘要： Linear active disturbance rejection control(LADRC)is a powerful control structure thanks to its performance in uncertainties,internal and external disturbances estimation and cancelation.An extended state observer(ESO)based controller is the key to the LADRC method.In this article,the LADRC scheme combined with a fractional-order integral action(FOILADRC)is proposed to improve the robustness of the standard LADRC.Using the robust closed-loop Bode’s ideal transfer function(BITF),an appropriate pole placement method is proposed to design the set-point tracking controller of the FOI-LADRC scheme.Numerical simulations and experimental results on a cart-pendulum system will illustrate the effectiveness of the proposed FOI-LADRC scheme for the disturbance rejection,the set-point tracking and the improved robustness.To illustrate the LADRC control schemes and to verify the performance of the proposed FOI-LADRC,compared to the standard LADRC and IOI-LADRC structures,two tests will be carried out.First,simulation tests on an academic example will be presented to show the effect of the different parameters of the control law on the performance of the closed-loop system.Then,these three control structures are implemented on an experimental test bench,the cart-pendulum system,to show their efficiency and to show the superiority of the proposed method compared to the two other structures.

摘要： For constrained linear parameter varying(LPV)systems,this survey comprehensively reviews the literatures on output feedback robust model predictive control(OFRMPC)over the past two decades from the aspects on motivations,main contributions,and the related techniques.According to the types of state observer systems and scheduling parameters of LPV systems,different kinds of OFRMPC approaches are summarized and compared.The extensions of OFRMPC for LPV systems to other related uncertain systems are also investigated.The methods of dealing with system uncertainties and constraints in different kinds of OFRMPC optimizations are given.Key issues on OFRMPC optimizations for LPV systems are discussed.Furthermore,the future research directions on OFRMPC for LPV systems are suggested.

摘要： This paper solves the robust control problem of robotic manipulator systems with uncertain dynamics by friction compensation approach. A weighting factor is introduced to distinguish the role of friction in control process by comparing the directions of sliding vector and friction. Utilizing the weighting factor, model-based and model-free adaptive friction compensation controllers are designed to achieve asymptotical tracking of the desired joint-space trajectory according to the knowledge of friction. The damping property of friction is fully used to improve the control performance by compensating the friction harmful for the stability, and on the other hand, utilizing the beneficial friction. Numerical simulations are given to demonstrate the control performance of the proposed approach.

摘要： Purpose-The purpose of this paper is to address the problem of control in a typical chaotic power system.Chaotic oscillations cannot only extremely endanger the stabilization of the power system but they can also not be controlled by adding the traditional controllers.So,the sliding mode control based on a fuzzy supervisor can sufficiently ensure perfect tracking and controlling in the presence of uncertainties.Closed-loop stability is proved using the Lyapunov stability theory.The simulation results show the effectiveness of the proposed method in damping chaotic oscillations of the power system,eliminating control signal chattering and also show less control effort in comparison with the methods considered in previous literatures.Design/methodology/approach-The sliding mode control based on a fuzzy supervisor can sufficiently ensure perfect tracking and controlling in the presence of uncertainties.Closed-loop stability is proved using the Lyapunov stability theory.Findings-Closed-loop stability is proved using the Lyapunov stability theory.The simulation results show the effectiveness of the proposed method in damping chaotic oscillations of power system,eliminating control signal chattering and also less control effort in comparison with the methods considered in previous literatures.Originality/value-Main contributions of the paper are as follows:the chaotic behavior of power systems with two uncertainty parameters and tracking reference signal for the control of generator angle and the controller signal are discussed;designing sliding mode control based on a fuzzy supervisor in order to practically implement for the first time;while the generator speed is constant,the proposed controller will enable the power system to go in any desired trajectory for generator angle at first time;stability of the closed-loop sliding mode control based on the fuzzy supervisor system is proved using the Lyapunov stability theory;simulation of the proposed controller shows that the chattering is low control signal.

摘要： Large load swing of a gantry crane, due to cable rnflexibility and rapid movement, needs to be rncontrolled. Herein, a rnwave-based approach interprets the cable motion as rntwo superposed traveling waves. To combine position rnand active swing control,rnthe trolley motion and load hoisting are carefully rndesigned here, and a practical approach is adopted to rndesign hoisting motions in the rnupward and downward manoeuvres, counteracting their rnreverse effects on the load swing. A robust control rnalgorithm, based on the rnmodel of the crane system, is proposed to realize the rntrolley and hoisting motions, allowing for load rnvariations and parameter rnuncertainties. This new solution to motion control of rna gantry crane works very well, and is stable and rnadaptive to large load rnvariations. As demonstrated in the simulation rnexperiments, it lands the load rapidly and exactly at rntarget and stops it dead, with nearly rnzero swing.

摘要： Large load swing of a gantry crane, due to cable rnflexibility and rapid movement, needs to be rncontrolled. Herein, a rnwave-based approach interprets the cable motion as rntwo superposed traveling waves. To combine position rnand active swing control,rnthe trolley motion and load hoisting are carefully rndesigned here, and a practical approach is adopted to rndesign hoisting motions in the rnupward and downward manoeuvres, counteracting their rnreverse effects on the load swing. A robust control rnalgorithm, based on the rnmodel of the crane system, is proposed to realize the rntrolley and hoisting motions, allowing for load rnvariations and parameter rnuncertainties. This new solution to motion control of rna gantry crane works very well, and is stable and rnadaptive to large load rnvariations. As demonstrated in the simulation rnexperiments, it lands the load rapidly and exactly at rntarget and stops it dead, with nearly rnzero swing.

摘要： Large load swing of a gantry crane, due to cable rnflexibility and rapid movement, needs to be rncontrolled. Herein, a rnwave-based approach interprets the cable motion as rntwo superposed traveling waves. To combine position rnand active swing control,rnthe trolley motion and load hoisting are carefully rndesigned here, and a practical approach is adopted to rndesign hoisting motions in the rnupward and downward manoeuvres, counteracting their rnreverse effects on the load swing. A robust control rnalgorithm, based on the rnmodel of the crane system, is proposed to realize the rntrolley and hoisting motions, allowing for load rnvariations and parameter rnuncertainties. This new solution to motion control of rna gantry crane works very well, and is stable and rnadaptive to large load rnvariations. As demonstrated in the simulation rnexperiments, it lands the load rapidly and exactly at rntarget and stops it dead, with nearly rnzero swing.

摘要： Large load swing of a gantry crane, due to cable rnflexibility and rapid movement, needs to be rncontrolled. Herein, a rnwave-based approach interprets the cable motion as rntwo superposed traveling waves. To combine position rnand active swing control,rnthe trolley motion and load hoisting are carefully rndesigned here, and a practical approach is adopted to rndesign hoisting motions in the rnupward and downward manoeuvres, counteracting their rnreverse effects on the load swing. A robust control rnalgorithm, based on the rnmodel of the crane system, is proposed to realize the rntrolley and hoisting motions, allowing for load rnvariations and parameter rnuncertainties. This new solution to motion control of rna gantry crane works very well, and is stable and rnadaptive to large load rnvariations. As demonstrated in the simulation rnexperiments, it lands the load rapidly and exactly at rntarget and stops it dead, with nearly rnzero swing.

摘要： developed for the trajectory tracking of robot manipulators with parameter uncertainty and outside disturbance. A functional-link neural network is used to approximate a unknown function. And a new network weight tuning law is given which is different to the existing σ-modification method. The proposed robust neural network controller based on this new tuning law can guarantee not only the boundedness of network weight but also the asymptotic stability of the tracking error. The numerical experiment shows that the proposed method is feasible and efficient.

摘要： developed for the trajectory tracking of robot manipulators with parameter uncertainty and outside disturbance. A functional-link neural network is used to approximate a unknown function. And a new network weight tuning law is given which is different to the existing σ-modification method. The proposed robust neural network controller based on this new tuning law can guarantee not only the boundedness of network weight but also the asymptotic stability of the tracking error. The numerical experiment shows that the proposed method is feasible and efficient.

摘要： developed for the trajectory tracking of robot manipulators with parameter uncertainty and outside disturbance. A functional-link neural network is used to approximate a unknown function. And a new network weight tuning law is given which is different to the existing σ-modification method. The proposed robust neural network controller based on this new tuning law can guarantee not only the boundedness of network weight but also the asymptotic stability of the tracking error. The numerical experiment shows that the proposed method is feasible and efficient.

摘要： developed for the trajectory tracking of robot manipulators with parameter uncertainty and outside disturbance. A functional-link neural network is used to approximate a unknown function. And a new network weight tuning law is given which is different to the existing σ-modification method. The proposed robust neural network controller based on this new tuning law can guarantee not only the boundedness of network weight but also the asymptotic stability of the tracking error. The numerical experiment shows that the proposed method is feasible and efficient.

摘要： developed for the trajectory tracking of robot manipulators with parameter uncertainty and outside disturbance. A functional-link neural network is used to approximate a unknown function. And a new network weight tuning law is given which is different to the existing σ-modification method. The proposed robust neural network controller based on this new tuning law can guarantee not only the boundedness of network weight but also the asymptotic stability of the tracking error. The numerical experiment shows that the proposed method is feasible and efficient.

摘要： developed for the trajectory tracking of robot manipulators with parameter uncertainty and outside disturbance. A functional-link neural network is used to approximate a unknown function. And a new network weight tuning law is given which is different to the existing σ-modification method. The proposed robust neural network controller based on this new tuning law can guarantee not only the boundedness of network weight but also the asymptotic stability of the tracking error. The numerical experiment shows that the proposed method is feasible and efficient.