scholarly journals Nonlinear Robust Control of a Hypersonic Flight Vehicle Using Fuzzy Disturbance Observer

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Lei Zhengdong ◽  
Wang Man ◽  
Yang Jianying
Keyword(s):  
Control System ◽  
Disturbance Observer ◽  
Sliding Mode ◽  
Inversion Method ◽  
Flight Vehicle ◽  
External Disturbances ◽  
Nonlinear Disturbance Observer ◽  
Hypersonic Flight Vehicle ◽  
Hypersonic Flight ◽  
Nonlinear Disturbance

This paper is concerned with a novel tracking controller design for a hypersonic flight vehicle in complex and volatile environment. The attitude control model is challengingly constructed with multivariate uncertainties and external disturbances, such as structure dynamic and stochastic wind disturbance. In order to resist the influence of uncertainties and disturbances on the flight control system, nonlinear disturbance observer is introduced to estimate them. Moreover, for the sake of high accuracy and sensitivity, fuzzy theory is adopted to improve the performance of the nonlinear disturbance observer. After the total disturbance is eliminated by dynamic inversion method, a cascade system is obtained and then stabilized by a sliding-mode controller. Finally, simulation results show that the strong robust controller achieves excellent performance when the closed-loop control system is influenced by mass uncertainties and external disturbances.

A fault-tolerant attitude tracking control of spacecraft using an anti-unwinding robust nonlinear disturbance observer

2019 ◽  
Vol 233 (16) ◽  
pp. 6005-6018 ◽  
Author(s):  
Syed Muhammad Amrr ◽  
M Nabi ◽  
Pyare Mohan Tiwari
Keyword(s):  
Disturbance Observer ◽  
Controller Design ◽  
Simulation Analysis ◽  
Fault Tolerant ◽  
Sliding Mode ◽  
Actuator Faults ◽  
External Disturbances ◽  
Nonlinear Disturbance Observer ◽  
Attitude Tracking ◽  
Nonlinear Disturbance

This paper investigates the application of an integral sliding mode control with a robust nonlinear disturbance observer to obtain an anti-unwinding spacecraft attitude tracking response with robustness against external disturbances, inertia matrix uncertainties, and actuator faults. In the controller design, external disturbances, uncertainties, and actuator faults are lumped together and estimated by the robust nonlinear disturbance observer. The proposed robust nonlinear disturbance observer guarantees the convergence of estimated lumped disturbance error to origin in finite time. The estimated disturbance is then used in the controller as a feed-forward compensator. Further, an adaptive law is also incorporated in the proposed controller to ensure additional robustness. The stability of the overall system and anti-unwinding characteristic are proved using the Lyapunov stability theory. Finally, numerical simulation analysis is performed in the presence of all the sources of lumped disturbances. It is observed that the proposed control strategy is ensuring higher accuracy, good steady-state precision, and eliminates the unwinding phenomenon.

Chattering-suppression sliding mode control of an autonomous underwater vehicle based on nonlinear disturbance observer and power function reaching law

2021 ◽  
pp. 014233122198986
Author(s):  
Qirong Tang ◽  
Yinghao Li ◽  
Ruiqin Guo ◽  
Daopeng Jin ◽  
Yang Hong ◽  
...  
Keyword(s):  
Trajectory Tracking ◽  
Tracking Control ◽  
Disturbance Observer ◽  
Autonomous Underwater Vehicle ◽  
Sliding Mode ◽  
External Disturbances ◽  
Trajectory Tracking Control ◽  
Nonlinear Disturbance Observer ◽  
Reaching Law ◽  
Nonlinear Disturbance

To improve the performance of autonomous underwater vehicle in trajectory tracking control, which is subject to system uncertainties and time-varying external disturbances, a nonlinear disturbance observer-based sliding mode controller is proposed in the study. First, a reaching law with a special power function and a hyperbolic tangent function is presented. Then an improved sliding mode controller based on the new reaching law is combined to decrease the reaching time and avoid chattering during the trajectory tracking control. Furthermore, to reduce the influence of the system uncertainties and external disturbances, a nonlinear disturbance observer is introduced to identify them. The error asymptotic convergence of the trajectory tracking control is proved by the Lyapunov-like function. Finally, under different environmental disturbances, plenty of simulations are carried out to verify the efficiency and robustness of the proposed method. Results show that when it is tracking different trajectories, the proposed method can suppress the chattering and reduce the disturbances effectively, while ensuring tracking performance.

scholarly journals Continuous Recursive Sliding Mode Control for Hypersonic Flight Vehicle with Extended Disturbance Observer

2015 ◽  
Vol 2015 ◽  
pp. 1-26 ◽  
Author(s):  
Yunjie Wu ◽  
Jianmin Wang
Keyword(s):  
Disturbance Observer ◽  
Sliding Mode ◽  
External Disturbance ◽  
Sliding Mode Controller ◽  
Flight Vehicle ◽  
Terminal Sliding Mode ◽  
Hypersonic Flight Vehicle ◽  
Hypersonic Flight ◽  
Compensation Factor ◽  
The Stability

A continuous recursive sliding mode controller (CRSMC) with extended disturbance observer (EDO) is proposed for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV) in the presence of multiple uncertainties under control constraints. Firstly, sliding mode tracking controller based on a set of novel recursive sliding mode manifolds is presented, in which the chattering problem is reduced. The CRSMC possesses the merits of both nonsingular terminal sliding mode controller (NTSMC) and high-order sliding mode controller (HOSMC). Then antiwindup controller is designed according to the input constraints, which adds a dynamic compensation factor in the CRSMC. For the external disturbance of system, an improved disturbance observer based on extended disturbance observer (EDO) is designed. The external disturbance is estimated by the disturbance observer and the estimated value is regarded as compensation in CRSMC for disturbance. The stability of the proposed scheme is analyzed by Lyapunov function theory. Finally, numerical simulation is conducted for cruise flight dynamics of HFV, where altitude is 110000 ft, velocity is 15060 ft/s, and Mach is 15. Simulation results show the validity of the proposed approach.

Sign in / Sign up

Export Citation Format

Share Document