Article
Engineering, Multidisciplinary
Yujin Wu, Kangjian Shao, Ning Wang, Zhongchao Deng
Summary: In this paper, an improved double finite-time observer-based line-of-sight guidance and finite-time control (IDFLOS-FC) scheme is proposed for sailboat path following. The salient features of the proposed scheme include introducing an actuator failure model, accurately observing the time-varying sideslip angle, using a radial basis function neural network to fit model uncertainty, and ensuring finite-time stability based on the Lyapunov method.
JOURNAL OF ZHEJIANG UNIVERSITY-SCIENCE A
(2023)
Article
Automation & Control Systems
Xincheng Zhuang, Haoping Wang, Sofiane Ahmed-Ali, Yang Tian
Summary: This article proposes a joint adaptive high-gain observer design method for a class of nonlinear systems subject to sampled output data measurements. The proposed method overcomes the difficulty caused by the coupling between the nonlinear term and unknown parameters. By introducing a closed-loop output predictor and a decoupling method, the proposed observer achieves exponential convergence of the estimation for both the unknown state and parameter.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2022)
Article
Engineering, Ocean
Zhiquan Liu
Summary: This study improves the robustness of the autopilot system by introducing a sideslip angle based cascade nonlinear steering model, an adaptive extended state observer, and a robust adaptive heading controller to handle un-modelled dynamics, time-varying parameters, and uncertain disturbances. The proposed observer based heading controller ensures that all system states and errors are uniformly ultimately bounded without prior knowledge of nonlinear characteristics and external disturbances.
APPLIED OCEAN RESEARCH
(2021)
Article
Engineering, Electrical & Electronic
Saeed Mahdizadeh, Hossein Gholizadeh, Reza Sharifi Shahrivar, Ebrahim Afjei, Ali Mosallanejad
Summary: This article introduces an ultra-high step-up DC-DC converter with a combination of boost converter, POS LLC, and VMC. The converter achieves more than 10 times voltage gain with lower duty cycle values while maintaining acceptable efficiency and voltage/current stress of the semiconductor. Experimental results show a 12 times increase in voltage gain and 90.5% efficiency with a 50% duty cycle. The topology is discussed in both continuous and discontinuous current modes, and comparisons are made with other topologies. The paper also compares the voltage/current stresses and efficiency of semiconductor components and discusses the behavior of efficiency for different effective factors. Simulation and experimental outcomes are presented and compared with theoretical results for a 120 W output power.
IET POWER ELECTRONICS
(2022)
Article
Automation & Control Systems
Yuehui Ji, Zhao Xu, Junjie Liu, Yu Song
Summary: Two distributed extended high-gain observers are proposed for the generalized strict-feedback system with external disturbance. The state dynamics are reconstructed based on limited measured output. The first observer ensures the semiglobal ultimate uniform convergence of the state estimation error, while the second observer is designed to be low-power yet effective. The effectiveness of the proposed observers is verified through experiments on a chaotic oscillator and a pendulum-cart system.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Engineering, Marine
Ruiting Chu, Zhiquan Liu, Zhenzhong Chu
Summary: This study aims to improve the performance of ship heading control and reduce tracking error. A sideslip angle compensation method and an improved super-twisting sliding mode control algorithm are proposed, which estimate the time-varying sideslip angle and external disturbance, and amendment of the heading error. To address the chattering effect of sliding mode control, a reaching law based on improved super-twisting algorithm is designed. The simulation results demonstrate the effectiveness of the proposed controller.
Article
Engineering, Marine
Hugan Zhang, Xianku Zhang, Renxiang Bu
Summary: An adaptive sliding mode control algorithm based on radial basis function neural networks(RBF-NNs) is proposed to solve the problems of external disturbances, internal model uncertainty and sideslip angle unknown in the process of underactuated ship path following. The RBF-NNs are used to estimate the sideslip angle, while the linear extended state observer (LESO) is introduced to estimate the total disturbances. This approach provides a potential reference for underactuated ship path following with unknown sideslip and disturbances.
Article
Automation & Control Systems
Shuang Zhang, Rui Liu, Kaixiang Peng, Wei He
Summary: This paper focuses on boundary output feedback control for a flexible two-link manipulator system with input saturation. Controllers such as BOFCs, high-gain observers, and auxiliary systems are proposed to address control issues, with the stability of the system proven through mathematical analysis and simulation results confirming the effectiveness of the controllers.
IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY
(2021)
Article
Automation & Control Systems
Bohao Zhu, James Lam, Yoshio Ebihara
Summary: This paper investigates the input-output gains of discrete-time and continuous-time positive periodic systems, finding equivalent relationships between l(1)- (L-1-) gain and l(infinity)- (L-infinity-) gain for these systems. Numerical examples are provided to illustrate the results.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2021)
Article
Automation & Control Systems
Ania Adil, Abdelghani Hamaz, Ibrahima N'Doye, Ali Zemouche, Taous-Meriem Laleg-Kirati, Fazia Bedouhene
Summary: In this paper, a high-gain observer design method is proposed for nonlinear systems with time-varying delayed output measurements. The HG/LMI observer allows for a larger bound of the time-delay compared to the standard high-gain methodology, and it adopts a lower tuning parameter value. The proposed methodology provides more general synthesis conditions and can be applied to systems with nonlinear outputs.
Article
Engineering, Mechanical
Mohammad Al Janaideh, Almuatazbellah M. Boker, Micky Rakotondrabe
Summary: This study proposes a new output-feedback tracking control scheme for a class of precision motion systems with unknown hysteresis nonlinearity and linear dynamics. The effectiveness of the method is demonstrated through simulation and experimental results.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Automation & Control Systems
Qian Zhang, Houhua Jing, Zhiyuan Liu, Yongfeng Jiang, Mingqin Gu
Summary: In this article, a novel vehicle sideslip angle estimation method is proposed using the Takagi-Sugeno (T-S) observer based on a piecewise affine (PWA) lateral dynamics model. Experimental results show that the proposed method can effectively estimate the sideslip angle under different road conditions.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Automation & Control Systems
Iasson Karafyllis
Summary: This paper presents a fundamental relation between Output Asymptotic Gains (OAG) and Input-to-Output Stability (IOS) gains for linear systems, showing that the minimum OAG is equal to the minimum IOS-gain and can be computed by solving a specific optimal control problem and by considering only periodic inputs.
SYSTEMS & CONTROL LETTERS
(2021)
Article
Engineering, Marine
Yanwei Huang, Xiaocheng Shi, Wenchao Huang, Shaobin Chen
Summary: This paper proposes an observer using internal model control to estimate the sideslip angle in the path following of unmanned surface vehicles. Simulation and experiments verify the effectiveness of the observer, showing that it has faster response speed, smaller steady-state error, and accurate estimation for large sideslip angles.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Computer Science, Information Systems
Tonatiuh Hernandez-Cortes, Miguel Amador-Macias, Ricardo Tapia-Herrera, Jesus Alberto Meda-Campana
Summary: This paper focuses on solving the output regulation problem using the new Francis equations for arbitrary reference/disturbance signals. The model is obtained by High-Gain observers, allowing regulation of unmodeled but measurable reference signals. The design involves fixing a globally attractive steady state using LMIs to control the decay rate within input bounds, while the regulation problem is solved by computing the steady-state input based on a modified set of regulation equations. The proposed approach is illustrated using the Furuta pendulum.
