scholarly journals Optimal Adaptive Control and Backstepping Control Method with Sliding Mode Differentiator

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Shengxin Sun ◽  
Yang Zhao ◽  
Hao Wu
Keyword(s):  
Finite Time ◽  
Control Method ◽  
Sliding Mode ◽  
Operation Time ◽  
Backstepping Control ◽  
Space Robot ◽  
Robot Arm ◽  
Model Uncertainties ◽  
External Disturbances ◽  
Time Control

In order to improve the success rate of space debris object capture, how to increase the resistance to interference in the space robot arm has become an issue of interest. In addition, since the space operation time is always limited, finite-time control has become another urgent requirement needed to be addressed. Considering external disturbances, two control methods are proposed in this paper to solve the control problem of space robot arm. Firstly, a linear sliding mode control method is proposed considering the model uncertainties and external disturbances. The robot arm can track the desired trajectory, while a trade-off between optimality and robustness of the solved system can be achieved. Then, in order to reduce conservativeness and relax restrictions on external disturbances, a novel backstepping control method based on a finite-time integral sliding mode disturbance observer is developed, which compensates for the effects of both model uncertainties and infinite energy-based disturbance inputs. Finally, simulation examples are given to illustrate the effectiveness of the proposed control method.

Immersion and invariance adaptive finite-time control of air-breathing hypersonic vehicles

2018 ◽  
Vol 233 (7) ◽  
pp. 2626-2641 ◽  
Author(s):  
Chao Han ◽  
Zhen Liu ◽  
Jianqiang Yi
Keyword(s):  
Control System ◽  
Finite Time ◽  
Control Method ◽  
Sliding Mode ◽  
Second Order ◽  
Hypersonic Vehicles ◽  
Terminal Sliding Mode ◽  
Air Breathing ◽  
Immersion And Invariance ◽  
Time Control

In this paper, a novel adaptive finite-time control of air-breathing hypersonic vehicles is proposed. Based on the immersion and invariance theory, an adaptive finite-time control method for general second-order systems is first derived, using nonsingular terminal sliding mode scheme. Then the method is applied to the control system design of a flexible air-breathing vehicle model, whose dynamics can be decoupled into first-order and second-order subsystems by time-scale separation principle. The main features of this hypersonic vehicle control system lie in the design flexibility of the parameter adaptive laws and the rapid convergence to the equilibrium point. Finally, simulations are conducted, which demonstrate that the control system has the features of fast and accurate tracking to command trajectories and strong robustness to parametric and non-parametric uncertainties.

A New Finite Time Control Solution for Robotic Manipulators Based on Nonsingular Fast Terminal Sliding Variables and the Adaptive Super-Twisting Scheme

2019 ◽  
Vol 14 (3) ◽  
Author(s):  
Vo Anh Tuan ◽  
Hee-Jun Kang
Keyword(s):  
Finite Time ◽  
Control Method ◽  
Sliding Mode ◽  
Robotic Manipulators ◽  
Control Law ◽  
Continuous Control ◽  
Terminal Sliding Mode ◽  
Finite Time Convergence ◽  
Position Errors ◽  
Time Control

In this study, a new finite time control method is suggested for robotic manipulators based on nonsingular fast terminal sliding variables and the adaptive super-twisting method. First, to avoid the singularity drawback and achieve the finite time convergence of positional errors with a fast transient response rate, nonsingular fast terminal sliding variables are constructed in the position errors' state space. Next, adaptive tuning laws based on the super-twisting scheme are presented for the switching control law of terminal sliding mode control (TSMC) so that a continuous control law is extended to reject the effects of chattering behavior. Finally, a new finite time control method ensures that sliding motion will take place, regardless of the effects of the perturbations and uncertainties on the robot system. Accordingly, the stabilization and robustness of the suggested control system can be guaranteed with high-precision performance. The robustness issue and the finite time convergence of the suggested system are totally confirmed by the Lyapunov stability principle. In simulation studies, the experimental results exhibit the effectiveness and viability of our proposed scheme for joint position tracking control of a 3DOF PUMA560 robot.

scholarly journals Disturbance Observer-Based Integral Backstepping Control for a Two-Tank Liquid Level System Subject to External Disturbances

2020 ◽  
Vol 2020 ◽  
pp. 1-22 ◽  
Author(s):  
Xiangxiang Meng ◽  
Haisheng Yu ◽  
Herong Wu ◽  
Tao Xu
Keyword(s):  
Control Strategy ◽  
Disturbance Observer ◽  
Control Method ◽  
Sliding Mode ◽  
Mass Conservation ◽  
Backstepping Control ◽  
Liquid Level ◽  
Level System ◽  
External Disturbances ◽  
Simulation And Experiment

A novel method of disturbance observer-based integral backstepping control is proposed for the two-tank liquid level system with external disturbances. The problem of external disturbances can be settled in this paper. Firstly, the mathematical model of the two-tank liquid level system is established based on fluid mechanics and principle of mass conservation. Secondly, an integral backstepping control strategy is designed in order to ensure liquid level tracking performance by making the tracking errors converge to zero in finite time. Thirdly, a disturbance observer is designed for the two-tank liquid level system with external disturbances. Finally, the validity of the proposed method is verified by simulation and experiment. By doing so, the simulation and experimental results prove that the scheme of disturbance observer-based integral backstepping control strategy can suppress external disturbances more effective than the disturbance observer-based sliding mode control method and has better dynamic and steady performance of the two-tank liquid level system.

Fixed-time fractional-order sliding mode control for nonlinear power systems

2020 ◽  
Vol 26 (17-18) ◽  
pp. 1425-1434 ◽  
Author(s):  
Sunhua Huang ◽  
Jie Wang
Keyword(s):  
Sliding Mode Control ◽  
Power System ◽  
Fractional Order ◽  
Finite Time ◽  
Control Method ◽  
Sliding Mode ◽  
Fixed Time ◽  
Sliding Mode Controller ◽  
Mode Control ◽  
Time Control

In this study, a fractional-order sliding mode controller is effectively proposed to stabilize a nonlinear power system in a fixed time. State trajectories of a nonlinear power system show nonlinear behaviors on the angle and frequency of the generator, phase angle, and magnitude of the load voltage, which would seriously affect the safe and stable operation of the power grid. Therefore, fractional calculus is applied to design a fractional-order sliding mode controller which can effectively suppress the inherent chattering phenomenon in sliding mode control to make the nonlinear power system converge to the equilibrium point in a fixed time based on the fixed-time stability theory. Compared with the finite-time control method, the convergence time of the proposed fixed-time fractional-order sliding mode controller is not dependent on the initial conditions and can be exactly evaluated, thus overcoming the shortcomings of the finite-time control method. Finally, superior performances of the fractional-order sliding mode controller are effectively verified by comparing with the existing finite-time control methods and integral order sliding mode control through numerical simulations.

scholarly journals Terminal Sliding Mode Control for Attitude Tracking of Spacecraft Based on Rotation Matrix

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Yong Guo ◽  
Shen-Min Song ◽  
Xue-Hui Li
Keyword(s):  
Finite Time ◽  
Control Method ◽  
Sliding Mode ◽  
Rotation Matrix ◽  
Sliding Mode Controller ◽  
External Disturbances ◽  
Terminal Sliding Mode ◽  
Attitude Tracking ◽  
Sliding Manifold ◽  
Attitude Tracking Control

Two finite-time controllers without unwinding for the attitude tracking control of the spacecraft are investigated based on the rotation matrix, in which a novel modified nonsingular fast terminal sliding manifold is developed to keep tr(R~)≠-1. The first terminal sliding mode controller can compensate external disturbances with known bounds, while the second one can compensate external disturbances with unknown bounds by using an adaptive control method. Since the first terminal sliding mode controller is continuous, it is able to avoid chattering phenomenon. Theoretical analysis shows that both the two controllers can make spacecraft follow a time-varying reference attitude signal in finite time. Numerical simulations also demonstrate that the proposed control schemes are effective.

scholarly journals Distributed Formation Control for Multiple Quadrotor Based on Multi-Agent Theory and Disturbance Observer

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Xiaohua Zhang ◽  
Junli Gao ◽  
Wenfeng Zhang ◽  
Tao Zeng ◽  
Liping Ye
Keyword(s):  
Finite Time ◽  
Formation Control ◽  
Control Method ◽  
Homogeneous System ◽  
Lyapunov Theory ◽  
Uncertain Parameters ◽  
External Disturbances ◽  
Agent Theory ◽  
Time Control ◽  
Multi Agent

This paper presents the disturbance observers-based distributed formation control for multiple quadrotor aircrafts with external disturbances and uncertain parameters using multi-agent theory and finite-time control method. Firstly, the finite-time disturbance observers are proposed to handle the external disturbances on the position-loop. Similarly, when there are both the uncertain parameters and external disturbances on the attitude-loop, the finite-time disturbance observers are designed to estimate the total lump disturbances. By skillfully using homogeneous system theory, Lyapunov theory, and multi-agent theory, the distributed formation control algorithms are developed. Finally, through simulations, the efficiency of the proposed method (including the convergence rate and disturbance rejection) is verified.

Continuous adaptive finite-time modified function projective lag synchronization of uncertain hyperchaotic systems

2016 ◽  
Vol 40 (3) ◽  
pp. 853-860 ◽  
Author(s):  
Xuan-Toa Tran ◽  
Hee-Jun Kang
Keyword(s):  
Finite Time ◽  
Control Method ◽  
Sliding Mode ◽  
External Disturbances ◽  
Lag Synchronization ◽  
Terminal Sliding Mode ◽  
Nonsingular Terminal Sliding Mode ◽  
Projective Lag Synchronization ◽  
Twisting Algorithm ◽  
Hyperchaotic Systems

This paper introduces an adaptive control method for finite-time modified function projective lag synchronization of uncertain hyperchaotic systems. Based upon novel nonsingular terminal sliding mode surfaces and the adaptive super-twisting algorithm, a controller is proposed to provide robustness, high precision and fast and finite-time modified function projective lag synchronization without the knowledge of the upper bound of uncertainties and unknown external disturbances. In addition, chattering is significantly attenuated due to the inherited continuity of the proposed controller. The global stability and finite-time convergence are rigorously proven. Numerical simulation is presented to demonstrate the effectiveness and feasibility of the proposed strategy and to verify the theoretical results.

Adaptive Finite-Time Synchronization of Non-Autonomous Chaotic Systems With Uncertainty

2012 ◽  
Vol 8 (3) ◽  
Author(s):  
Mohammad Pourmahmood Aghababa ◽  
Hasan Pourmahmood Aghababa
Keyword(s):  
Finite Time ◽  
Chaotic Systems ◽  
Time Synchronization ◽  
The State ◽  
Control Technique ◽  
Model Uncertainties ◽  
Unknown Parameters ◽  
External Disturbances ◽  
Time Control ◽  
Engineering Sciences

Due to its useful applications in real world processes, synchronization of chaotic systems has attracted the attention of many researchers of mathematics, physics and engineering sciences. In practical situations, many chaotic systems are inevitably disturbed by model uncertainties and external disturbances. Furthermore, in practice, it is hard to determine the precise values of the chaotic systems’ parameters in advance. Besides, from a practical point of view, it is more desirable to achieve synchronization in a given finite time. In this paper, we investigate the problem of finite-time chaos synchronization between two different chaotic systems in the presence of model uncertainties, external disturbances and unknown parameters. Both autonomous and non-autonomous chaotic systems are taken into account. To tackle the unknown parameters, appropriate adaptation laws are proposed. Using the adaptation laws and finite-time control technique, an adaptive robust finite-time controller is designed to guarantee that the state trajectories slave system converge to the state trajectories of the master system in a given finite time. Some numerical simulations are presented to verify the robustness and usefulness of the proposed finite-time control technique.

Sign in / Sign up

Export Citation Format

Share Document