IET Control Theory & Applications
Volume 12, Issue 12, 14 August 2018
Volumes & issues:
Volume 12, Issue 12
14 August 2018
-
- Author(s): Pan Yu ; Min Wu ; Jinhua She ; Kang-Zhi Liu ; Yosuke Nakanishi
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1673 –1682
- DOI: 10.1049/iet-cta.2017.1343
- Type: Article
- + Show details - Hide details
-
p.
1673
–1682
(10)
To suppress disturbances in uncertain tracking control systems with an input-delay, a disturbance predictor based on a high-order generalised extended-state observer is devised in this study. A smooth enough approximation of the disturbance is first made, then the approximation ahead of delay-time is predicted. The construction of the disturbance predictor is based on a truncated Taylor polynomial. To facilitate the analysis and design of the closed-loop control system, control gains for the nominal plant are designed in advance. Then the stability analysis for the closed-loop system is conducted, which yields a robust stability condition. As the disturbance predictor takes into consideration the influence of the input-delay, the presented method enables the enhancement of the disturbance-rejection performance. Finally, comparisons of the developed method with major methods in this field are conducted to validate the developed method and to demonstrate its advantages.
- Author(s): Eugenio Alcala ; Vicenç Puig ; Joseba Quevedo ; Teresa Escobet
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1683 –1693
- DOI: 10.1049/iet-cta.2017.1154
- Type: Article
- + Show details - Hide details
-
p.
1683
–1693
(11)
This study presents a solution for the integrated longitudinal and lateral control problem of urban autonomous vehicles. It is based on a gain-scheduling linear parameter-varying (LPV) control approach combined with the use of an Unknown Input Observer (UIO) for estimating the vehicle states and friction force. Two gain-scheduling LPV controllers are used in cascade configuration that use the kinematic and dynamic vehicle models and the friction and observed states provided by the Unknown Input Observer (UIO). The LPV–UIO is designed in an optimal manner by solving a set of linear matrix inequalities (LMIs). On the other hand, the design of the kinematic and dynamic controllers lead to solve separately two LPV–Linear Quadratic Regulator problems formulated also in LMI form. The UIO allows to improve the control response in disturbance affected scenarios by estimating and compensating the friction force. The proposed scheme has been integrated with a trajectory generation module and tested in a simulated scenario. A comparative study is also presented considering the cases that the friction force estimation is used or not to show its usefulness.
- Author(s): Hansheng Wu
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1694 –1703
- DOI: 10.1049/iet-cta.2017.1359
- Type: Article
- + Show details - Hide details
-
p.
1694
–1703
(10)
In this study, the problem of robust output tracking control is considered for a class of uncertain strict-feedback non-linear systems with any input saturation. A new design approach, called an adaptive design approach, is proposed to deal with saturated input non-linearities. The main merits of the proposed adaptive design approach can be summarised as follows. (i) It is completely unnecessary to know any information on input saturation non-linearities. (ii) By utilising the proposed adaptive design approach, the resulting control schemes will have a specially simple structure. (iii) The adaptive design approach proposed in this study is also easy to understand for the system designers, and by combining the proposed adaptive design approach with other control ones, a number of interesting results can be expected for a rather large class of dynamical systems with saturation in the actuators. Finally, a numerical example is given to illustrate the design procedure, and the corresponding simulations are also implemented to show the validity of the theoretical results.
- Author(s): Xiao Zhang ; Feng Ding ; Ling Xu ; Erfu Yang
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1704 –1713
- DOI: 10.1049/iet-cta.2018.0156
- Type: Article
- + Show details - Hide details
-
p.
1704
–1713
(10)
This study presents a combined parameter and state estimation algorithm for a bilinear system described by its observer canonical state-space model based on the hierarchical identification principle. The Kalman filter is known as the best state filter for linear systems, but not applicable for bilinear systems. Thus, a bilinear state observer (BSO) is designed to give the state estimates using the extremum principle. Then a BSO-based recursive least squares (BSO-RLS) algorithm is developed. For comparison with the BSO-RLS algorithm, by dividing the system into three fictitious subsystems on the basis of the decomposition–coordination principle, a BSO-based hierarchical least squares algorithm is proposed to reduce the computation burden. Moreover, a BSO-based forgetting factor recursive least squares algorithm is presented to improve the parameter tracking capability. Finally, a numerical example illustrates the effectiveness of the proposed algorithms.
- Author(s): Xiao-Wei Jiang ; Chao-Yang Chen ; Qing-Sheng Yang ; Xiu-Jun Qu ; Huai-Cheng Yan
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1714 –1721
- DOI: 10.1049/iet-cta.2017.1164
- Type: Article
- + Show details - Hide details
-
p.
1714
–1721
(8)
In this study, the optimal tracking performance for single-input multiple-output (SIMO) systems under control energy constraints is investigated. The packet dropouts in the upstream channel and down channel are adequately considered. The minimal tracking error is obtained by searching through all stablising controllers. The main results of this study show that the optimal tracking performance in these kinds of system is closely dependent on the structure of the given plant and statistic characteristics of the reference signal. Furthermore, the packet dropouts in the communication channel will degenerate the tracking performance. Finally, a typical example is given to illustrate the theoretical results.
- Author(s): Mojtaba Sharifi ; Hassan Salarieh ; Saeed Behzadipour ; Mahdi Tavakoli
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1722 –1729
- DOI: 10.1049/iet-cta.2017.1253
- Type: Article
- + Show details - Hide details
-
p.
1722
–1729
(8)
A non-linear robust adaptive bilateral impedance controller is proposed to provide the absolute stability of multi-DOF teleoperation systems with communication delays, in addition to the force and position tracking performance. The proposed controller realises two desired (or reference) impedance models for the master and slave robots using a new non-linear robust version of the model reference adaptive control scheme. Using the absolute stability criterion, the robustness condition of the teleoperation system against communication delays is obtained, resulting in suitable adjustments of parameter values in the desired impedance models. In addition, using the Lyapunov stability theorem, the tracking performance of the master and slave robots and the robustness of the proposed controller against parametric and bounded unstructured modelling (non-parametric) uncertainties were proven. The performance of the proposed non-linear bilateral controller is investigated by performing some experiments on non-linear multi-degree-of-freedom (DOF) telerobots with and without communication delays.
- Author(s): Lu Liu ; Shuo Zhang ; Dingyu Xue ; Yang Quan Chen
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1730 –1736
- DOI: 10.1049/iet-cta.2017.1145
- Type: Article
- + Show details - Hide details
-
p.
1730
–1736
(7)
Most of the existing controller tuning methods are based on accurate system model and sensitive to some inevitable uncertainties and unmeasurable disturbance. Aiming at this problem, a thorough robustness analysis on a typical kind of fractional-order (FO) delay system has been made in this study. A kind of robust FO proportional and derivative controller is proposed based on phase and gain margins. The tuning methods are demonstrated under different circumstances, namely there is gain variation, time constant variation, order variation or even multiple parameters variations in system transfer function. Simulation results show that the closed-loop control system with the proposed controller can achieve both robustness and satisfactory dynamic performance, and outperform the conventional proportional–integral–derivative controller in all cases.
- Author(s): Jianglong Yu ; Xiwang Dong ; Qingdong Li ; Zhang Ren
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1737 –1747
- DOI: 10.1049/iet-cta.2017.1397
- Type: Article
- + Show details - Hide details
-
p.
1737
–1747
(11)
Practical time-varying formation tracking analysis and design problems for multiple non-holonomic mobile robot systems with directed interaction topologies are investigated by using the distributed extended state observers, where the practical time-varying formation tracking error is controlled within an arbitrary small bound. Different from the previous work, the dynamics of each robot is non-holonomic and the followers are required to form the practical time-varying formation with respect to the leader of unknown control inputs. Besides, the disturbances and the uncertainties are considered in the dynamic model of the follower. Distributed extended state observers are constructed by using only the neighbouring relative information to estimate both the state and the unknown control inputs of the leader simultaneously. A practical time-varying formation tracking protocol is presented based on the distributed extended state observers. The gain matrices of the observers in the practical time-varying formation tracking protocol can be obtained by solving three linear matrix inequalities. Moreover, the stability of the multiple non-holonomic mobile robot system under the proposed protocol is proved by using the properties of the Laplacian matrix and the Lyapunov stability theory. Finally, two numerical simulation examples are given to illustrate the effectiveness of the obtained theoretical results.
- Author(s): Bin-Bin He ; Hua-Cheng Zhou ; YangQuan Chen ; Chun-Hai Kou
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1748 –1754
- DOI: 10.1049/iet-cta.2017.1144
- Type: Article
- + Show details - Hide details
-
p.
1748
–1754
(7)
In this study, the asymptotical stability for several classes of fractional order differential systems with time delay is investigated. The authors first present an integral inequality by which the Halanay inequality is extended to fractional order case. Based on the generalised Halanay inequality, the authors establish several asymptotical stability conditions under which the fractional order systems with time delay are asymptotically stable. It is worth to note that these stability conditions are easy to check without resorting to the solution expression of the systems.
- Author(s): Fidel Meléndez-Vázquez and Rafael Martínez-Guerra
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1755 –1762
- DOI: 10.1049/iet-cta.2017.1117
- Type: Article
- + Show details - Hide details
-
p.
1755
–1762
(8)
In this study, the problems of synchronisation and anti-synchronisation are solved for commensurate and incommensurate fractional chaotic systems. A reduced-order fractional integral observer is proposed for fractional systems satisfying a fractional algebraic observability condition, which is shown to be Mittag–Leffler stable. This observer is used as a slave system, whose states are synchronised with the states of the chaotic system, which acts as a master. The observer uses a reduced set of measurable signals from the master system, solving the anti-synchronisation problem as a straightforward extension of the synchronisation one. Numerical simulations on the fractional Lorenz and Rössler systems assess the performance of the proposed methodology.
- Author(s): Xiao Wang ; Jie Guo ; Shengjing Tang
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1763 –1772
- DOI: 10.1049/iet-cta.2017.1309
- Type: Article
- + Show details - Hide details
-
p.
1763
–1772
(10)
This study develops a neural network (NN)-based multivariable fixed-time terminal sliding mode control (MFTTSMC) strategy for re-entry vehicles (RVs) with uncertainties. A coupled MFTTSMC scheme is designed for the attitude system on the basis of feedback linearisation. A saturation function is introduced to avoid the singularity problem. Adaptive NNs are employed to approximate the uncertainties in RVs, thus alleviating chattering without sacrificing robustness. The whole closed-loop system is proven to be bounded and tracking errors are fixed-time stable. Simulations verify the effectiveness of the proposed strategy.
Enhancement of disturbance-rejection performance of uncertain input-delay systems: a disturbance predictor approach
Gain-scheduling LPV control for autonomous vehicles including friction force estimation and compensation mechanism
Simple adaptive robust output tracking control schemes of uncertain parametric strict-feedback non-linear systems with unknown input saturations
State filtering-based least squares parameter estimation for bilinear systems using the hierarchical identification principle
Optimal tracking performance for SIMO systems with packet dropouts and control energy constraints
Impedance control of non-linear multi-DOF teleoperation systems with time delay: absolute stability
General robustness analysis and robust fractional-order PD controller design for fractional-order plants
Practical time-varying formation tracking for multiple non-holonomic mobile robot systems based on the distributed extended state observers
Asymptotical stability of fractional order systems with time delay via an integral inequality
Reduced-order fractional integral observer for synchronisation and anti-synchronisation of fractional-order chaotic systems
Neural network-based multivariable fixed-time terminal sliding mode control for re-entry vehicles
-
- Author(s): Chang-Jiang Li and Guo-Ping Liu
- Source: IET Control Theory & Applications, Volume 12, Issue 12, p. 1773 –1779
- DOI: 10.1049/iet-cta.2017.0847
- Type: Article
- + Show details - Hide details
-
p.
1773
–1779
(7)
This study investigates the output consensus problem for a class of non-linear networked multi-agent systems with switching topology and time-varying delays. To synchronise the outputs of the agents, novel distributed data-driven consensus protocols are proposed, where the reference input is designed to be the time-varying average of the agents' output. To avoid the self-tracking phenomenon, the delayed information is introduced in the protocol. The proposed methods merely depend on the input and output data of the neighbouring agents, without using explicit or implicit information of its mathematical model. Sufficient conditions are derived to guarantee the closed-loop stability and consensus, with the convergence rate obtained. Numerical and practical examples are conducted to demonstrate the effectiveness of the proposed protocols.
Data-driven consensus for non-linear networked multi-agent systems with switching topology and time-varying delays
Most viewed content
Most cited content for this Journal
-
Finite-time stability of interconnected impulsive switched systems
- Author(s): Guangdeng Zong ; Hangli Ren ; Linlin Hou
- Type: Article
-
Event-based security control for discrete-time stochastic systems
- Author(s): Derui Ding ; Zidong Wang ; Guoliang Wei ; Fuad E. Alsaadi
- Type: Article
-
Survey on semi-tensor product method with its applications in logical networks and other finite-valued systems
- Author(s): Jianquan Lu ; Haitao Li ; Yang Liu ; Fangfei Li
- Type: Article
-
Optimal control for networked control systems with disturbances: a delta operator approach
- Author(s): Yuan Yuan ; Huanhuan Yuan ; Zidong Wang ; Lei Guo ; Hongjiu Yang
- Type: Article
-
Filtering-based iterative identification for multivariable systems
- Author(s): Yanjiao Wang and Feng Ding
- Type: Article