Back-stepping control of two-link flexible manipulator based on an extended state observer

2015 ◽  
Vol 56 (10) ◽  
pp. 2312-2322 ◽  
Author(s):  
Hongjiu Yang ◽  
Yang Yu ◽  
Yuan Yuan ◽  
Xiaozhao Fan
Keyword(s):  
State Observer ◽  
Extended State Observer ◽  
Flexible Manipulator ◽  
Extended State ◽  
Back Stepping Control

Sampled-data extended state observer-based backstepping control of two-link flexible manipulator

2019 ◽  
Vol 41 (13) ◽  
pp. 3581-3599 ◽  
Author(s):  
Umesh Kumar Sahu ◽  
Bidyadhar Subudhi ◽  
Dipti Patra
Keyword(s):  
Control Strategies ◽  
Estimation Error ◽  
Experimental Studies ◽  
State Observer ◽  
Lyapunov Theory ◽  
Extended State Observer ◽  
Flexible Manipulator ◽  
Sampled Data ◽  
Extended State ◽  
Model Uncertainties

Currently, space robots such as planetary robots and flexible-link manipulators (FLMs) are finding specific applications to reduce the cost of launching. However, the structural flexible nature of their arms and joints leads to errors in tip positioning owing to tip deflection. The internal model uncertainties and disturbance are the key challenges in the development of control strategies for tip-tracking of FLMs. To deal with these challenges, we design a tip-tracking controller for a two-link flexible manipulator (TLFM) by developing a sampled-data extended state observer (SD-ESO). It is designed to reconstruct uncertain parameters for accurate tip-tracking control of a TLFM. Finally, a backstepping (BS) controller is designed to attenuate the estimation error and other bounded disturbances. Convergence and stability of the proposed control system are investigated by using Lyapunov theory. The benefits (control performance and robustness) of the proposed SD-ESO-based BS controller are compared with other similar approaches by pursuing both simulation and experimental studies. It is observed from the results obtained that SD-ESO-based BS Controller effectively compensates the deviation in tip-tracking performance of TLFM due to non-minimum phase behavior and model uncertainties with an improved transient response.

Extended state observer-based back-stepping control for hypersonic reentry vehicle with input constraints

2018 ◽  
Vol 36 (3) ◽  
pp. 921-947 ◽  
Author(s):  
Chen Chen ◽  
Guangfu Ma ◽  
Yueyong Lyu ◽  
Yanning Guo
Keyword(s):  
State Observer ◽  
Lyapunov Theory ◽  
Extended State Observer ◽  
Control Technique ◽  
Control Input ◽  
Sigmoid Function ◽  
Input Constraints ◽  
Extended State ◽  
Reentry Vehicle ◽  
Back Stepping Control

Abstract This paper investigates the attitude-tracking control problem of hypersonic reentry vehicle in cases of multiple uncertainties, external disturbances and input constraints. The controller design is based on synthesizing the extended state observer (ESO) into a back-stepping control technique. This control-oriented model is formulated with mismatched and matched uncertainties. They reflect the total disturbances that group different types of aerodynamic uncertainties and external moment disturbances. In order to improve the system robustness, a sigmoid function-based ESO is first proposed. This will estimate the total disturbance and is equipped with a controller. The sigmoid smooth function is also introduced for the purpose of handling the input constraints. This will approximate saturation and guarantee that the control input is bounded. Error states between the actual control input and the desired control input are integrated to compensate for the saturation effect. Following this, the stability of the closed-loop system is proved within the Lyapunov theory framework. Several simulations are then investigated to illustrate the effectiveness of the proposed constrained attitude control scheme.

scholarly journals Fault-tolerant control for a class of n-order systems based on fast terminal sliding mode and extended state observer

2021 ◽  
pp. 002029402110286
Author(s):  
Pu Yang ◽  
Peng Liu ◽  
ChenWan Wen ◽  
Huilin Geng
Keyword(s):  
Fault Tolerant ◽  
Sliding Mode ◽  
Singular Control ◽  
Fault Tolerant Control ◽  
State Observer ◽  
Extended State Observer ◽  
Extended State ◽  
Terminal Sliding Mode ◽  
Fast Terminal Sliding Mode ◽  
Terminal Sliding Surface

This paper focuses on fast terminal sliding mode fault-tolerant control for a class of n-order nonlinear systems. Firstly, when the actuator fault occurs, the extended state observer (ESO) is used to estimate the lumped uncertainty and its derivative of the system, so that the fault boundary is not needed to know. The convergence of ESO is proved theoretically. Secondly, a new type of fast terminal sliding surface is designed to achieve global fast convergence, non-singular control law and chattering reduction, and the Lyapunov stability criterion is used to prove that the system states converge to the origin of the sliding mode surface in finite time, which ensures the stability of the closed-loop system. Finally, the effectiveness and superiority of the proposed algorithm are verified by two simulation experiments of different order systems.

Sign in / Sign up

Export Citation Format

Share Document