Article
Agricultural Engineering
Zhansheng Song, Longlong Wang, Yunmeng Liu, Kangda Wang, Zhizhu He, Zhongxiang Zhu, Jiahao Qin, Zhen Li
Summary: This study aims to enhance the lateral stability of tractors by implementing an active steering system that can convert roll and pitch motion to restore the tractor attitude in potential rollover situations. A sliding mode control algorithm and a lateral stability indicator are used to reduce the risk of tractor rollovers, showing that the proposed control strategy is effective and robust.
BIOSYSTEMS ENGINEERING
(2022)
Article
Automation & Control Systems
Ganghui Shen, Yuanqing Xia, Jinhui Zhang, Bing Cui
Summary: This paper presents a new continuous adaptive super-twisting sliding mode control (ASTSMC) method for the altitude trajectory tracking control problem of reentry vehicle subject to bounded uncertainty. The proposed method, based on conventional super-twisting sliding mode control (STSMC) and adaptive gain technique, improves tracking accuracy and achieves high control performance. By employing fast power rate reaching law and modified fast nonsingular terminal sliding mode (FNTSM) surface, the designed controller achieves faster convergence and stronger robustness than conventional STSMC methods. The finite-time stability of the closed-loop system is proved through Lyapunov theory, and simulation results validate the superiority of the proposed controller.
Article
Agriculture, Multidisciplinary
Zhizhu He, Zhansheng Song, Longlong Wang, Xu Zhou, Junxiao Gao, Kangda Wang, Minli Yang, Zhen Li
Summary: The application of active steering technology is an effective approach to solving the rollover problem for small tractors under complicated road conditions. This study focuses on the improvement of a lateral stability index and the use of sliding mode control technology based on an exponential terminal sliding mode surface. Real vehicle tests were conducted on various road pavements and typical off-road pavements to evaluate the effectiveness of the proposed control methods.
COMPUTERS AND ELECTRONICS IN AGRICULTURE
(2023)
Article
Automation & Control Systems
Nitin K. Singh, Abhisek K. Behera
Summary: In this paper, a twisting observer is proposed for robustly estimating the states of a second-order uncertain system. The observer approximates the unknown sign term for the non-measurable state with a delayed output-based switching function, and achieves the desired steady-state accuracy by controlling the delay parameter. The application of the observer to output feedback stabilization is also discussed.
Article
Engineering, Marine
Wei Liu, Hui Ye, Xiaofei Yang
Summary: In this paper, the impact of time-varying external disturbances on the trajectory tracking accuracy of an underactuated unmanned surface vehicle (USV) is addressed. To ensure accuracy, a reduced-order extended state observer (ESO) and a super-twisting second-order sliding mode controller are adopted. The ESO handles the unknown time-varying sideslip angle, while the super-twisting technology reduces the chattering effect. Stability analysis using the Lyapunov method proves that the proposed controllers ensure convergence of tracking errors in finite time. Simulation experiments comparing the proposed super-twisting sliding mode control (STSMC) and adaptive sliding mode control (ASMC) methods demonstrate that the STSMC method enables the USV to track the reference trajectory successfully, with significantly reduced chattering compared to ASMC.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Automation & Control Systems
Xiaowei Yang, Yaowen Ge, Wenxiang Deng, Jianyong Yao
Summary: This paper investigates an asymptotic adaptive dynamic surface tracking control strategy for uncertain full-state constrained nonlinear systems subject to parametric uncertainties and external disturbances. A novel disturbance estimator (DE) is used to compensate for external disturbances, while the parametric uncertainties are handled with a synthesized adaptive law. The backstepping design framework employs a novel adaptive-gain nonlinear filter, avoiding complexity explosion and conservatism of filter gain selection. The theoretical analysis confirms the assured asymptotic tracking performance with the proposed controller. Simulation cases demonstrate the validity of the proposed controller.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2022)
Article
Agriculture, Multidisciplinary
Jinlin Sun, Qiushi Li, Shihong Ding, Gaoyong Xing, Liping Chen
Summary: This paper proposes a novel fixed-time generalized super-twisting control scheme to tackle common problems and improve path tracking performance in autonomous agricultural vehicles. With the design of a fixed-time integral sliding mode surface, innovative auxiliary system dynamics, and the use of a generalized super-twisting controller, the proposed scheme demonstrates superior performance and robustness in field experiments.
COMPUTERS AND ELECTRONICS IN AGRICULTURE
(2023)
Article
Engineering, Electrical & Electronic
Jianshan Zhou, Daxin Tian, Zhengguo Sheng, Xuting Duan, Guixian Qu, Dongpu Cao, Xuemin Shen
Summary: A novel decentralized robust control approach is proposed in this paper to address the external disturbances in vehicle platooning. By combining a super-twisting second-order sliding mode strategy and a disturbance observer, a super-twisting SOSMDO platoon controller is designed, and the theoretical analysis proves its convergence and stability.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2022)
Article
Computer Science, Information Systems
Oliver Kruse, Aidana Mukhamejanova, Paolo Mercorelli
Summary: This paper deals with the modeling and control of differential steering using Sliding Mode Control and a Super-Twisting Algorithm. A single-track mechanical model is proposed and validated, and a control strategy based on the Super-Twisting Algorithm is proposed to improve the travel comfort and stability of vehicular motion.
Article
Energy & Fuels
Mojtaba Ayaz Khoshhava, Hossein Abootorabi Zarchi, Gholamreza Arab Markadeh
Summary: This paper presents a direct speed and flux control system for Dual Stator Winding Induction Machines based on Super Twisting Sliding Mode Control, as well as a novel torque-sharing algorithm and full order observer. Experimental tests confirm the effectiveness of the proposed control method in various speed regions.
IEEE TRANSACTIONS ON ENERGY CONVERSION
(2021)
Article
Automation & Control Systems
Hernan Haimovich, Leonid Fridman, Jaime A. Moreno
Summary: The application of sliding-mode control strategies based on super-twisting algorithms in the presence of time- and state-dependent perturbations is highly challenging. This article provides an important generalization by employing disturbance-tailored super-twisting ideas, allowing for greater applicability.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Automation & Control Systems
Lejun Chen, James F. Whidborne
Summary: This paper proposes a generalized multivariable super-twisting observer for a class of nonlinear systems with multiplicatively linked unmeasured variables. It provides a sufficient condition for the convergence of the reconstruction errors associated with the unmeasurable variables to zero in finite time. The approach is then applied to estimate aircraft icing accretion despite unreliable sensor measurement, and the results show the capability of the observer to estimate the change of drag coefficient induced by icing accretion and reconstruct the unreliable pitch rate sensor measurement simultaneously.
Article
Automation & Control Systems
Fernando Lopez-Caamal, Jaime A. Moreno
Summary: This article presents a global, finite-time observer for continuous-time nonlinear systems, which has good performance and robustness, and requires the linear part of the plant to be observable.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Computer Science, Artificial Intelligence
Kun Wang, Xiaoping Liu, Yuanwei Jing
Summary: This paper investigates a robust super-twisting sliding mode control (SMC) based on a disturbance observer for TCP network systems with unknown disturbance. By introducing a super-twisting algorithm and designing a disturbance observer, the estimation accuracy of the model is improved, and the stability of the closed-loop control system is achieved.
NEURAL COMPUTING & APPLICATIONS
(2022)
Article
Computer Science, Information Systems
Pei Dai, Binbin Yan, Shuangxi Liu, Ruifan Liu, Mingang Wang
Summary: An accurate longitudinal dynamic model for a morphing waverider is presented in this paper, along with a control-oriented longitudinal dynamic model that separates additional morphing forces and moments. An adaptive super twisting sliding mode controller is applied to track the optimized trajectory during the entire morphing process. The controller reduces mean and maximum tracking errors of the pitch angle compared with traditional sliding mode controller under nominal condition simulations and 500 Monte Carlo runs.
Article
Automation & Control Systems
Andrei Battistel, Tiago Roux Oliveira, Victor Hugo Pereira Rodrigues, Leonid Fridman
Summary: This paper presents an extension of the Binary Model Reference Adaptive Control (BMRAC) method for uncertain multivariable systems with non-uniform arbitrary relative degrees. It uses only output feedback and is applied to inertially stabilized platforms. The proposed controller achieves global and exact tracking by using a newly proposed differentiator with dynamic gains.
EUROPEAN JOURNAL OF CONTROL
(2022)
Article
Automation & Control Systems
Victor Hugo Pereira Rodrigues, Liu Hsu, Tiago Roux Oliveira, Leonid Fridman
Summary: This paper introduces a new adaptive sliding mode control approach that is capable of handling parametric uncertainties and disturbances, ensuring both transient and steady-state performance. By combining monitoring and barrier functions, the adaptive process is divided into two stages, effectively confining tracking error within a small residual set.
INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING
(2022)
Article
Automation & Control Systems
Luis Ovalle, Hector Rios, Miguel Llama, Leonid Fridman
Summary: This article presents a robust output-feedback control scheme for stabilizing a class of nonlinear underactuated mechanical systems in the presence of coupled disturbances. The scheme is based on coupled sliding-mode control, eliminating the need for transformation into the normal form. The proposed output approach combines a super-twisting controller and a high-order sliding-mode observer to robustly stabilize the system's origin asymptotically.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Automation & Control Systems
Marco A. Gomez, Christopher D. Cruz-Ancona, Leonid Fridman
Summary: We propose a new continuous Lyapunov redesign (LR) methodology based on the super twisting algorithm, for robust stabilization of uncertain time-delay systems. The main feature of this approach is simultaneous adjustment of chattering effect and achieving asymptotic stabilization of uncertain system, which is not possible with continuous approximation of unit control. The basis of super twisting based LR methodology is a well-known class of Lyapunov-Krasovskii functionals, where the time derivative of this class allows definition of a delay-free sliding manifold for compensating a certain class of smooth uncertainties.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2023)
Article
Automation & Control Systems
Jorge Davila, Markus Tranninger, Leonid Fridman
Summary: This note presents a finite-time observer for a class of linear time-varying systems with bounded unknown inputs. The observer design utilizes the structural properties of the system and applies the robust exact differentiator in a block form through a linear operator, eliminating the need for additional stabilizing terms. The proposed observer provides an exact estimate of the states after a finite transient time despite the potential instability of the system and the effects of bounded unknown inputs.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Automation & Control Systems
Hector Rios, Jorge Davila, Leonid Fridman
Summary: This paper proposes a family of homogeneity-based observers to estimate the state of linear systems with parametric uncertainties and unknown inputs. The observers possess robustness, finite- and fixed-time convergence properties depending on the considered uncertainties. The structure of these observers is simple and can be applied to multiple-outputs without needing additional observers or complex transformations. Simulation results demonstrate the performance of the proposed observers.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Computer Science, Information Systems
Murad M. Shoman, Hocine Imine, Ennia Mariapaola Acerra, Claudio Lantieri
Summary: Understanding how cyclists behave can lead to the construction of better roadways to improve cycling safety and comfort. This study examines cyclist behavior using an instrumented city bicycle to collect data on dynamics, trajectory, speed, and interactions with other road users. The results provide important data to evaluate cycling safety and comfort in snowy weather conditions and the perception-reaction behavior of cyclists, allowing for the evaluation of infrastructure-related risks and the establishment of measures to improve cycling safety.
Article
Automation & Control Systems
Christopher D. Cruz-Ancona, Leonid Fridman, Hussein Obeid, Salah Laghrouche, Claudia A. Perez-Pinacho
Summary: In adaptive sliding mode control methods, an updating gain strategy is essential for dealing with matched bounded perturbations. However, estimating the finite time of an adaptive design is complicated as it depends on the unknown perturbation's upper-bound and initial conditions' size. This brief proposes a uniform adaptive reaching phase strategy (ARPS) within a predefined reaching-time. The usage of the proposed ARPS in perturbed MIMO systems with uncertain control matrix solves two issues: uniform reaching phase and adaptation to the perturbation norm.
Article
Automation & Control Systems
Hector Rios, Manuel Mera, Leonid Fridman
Summary: This article presents a fault-tolerant control scheme for uncertain systems in the presence of time- and state-dependent actuator faults and/or failures, and component faults. The proposed scheme is based on a continuous integral sliding-mode control approach and a fixed control allocation technique. It includes a robust linear controller and a multivariable Super-Twisting algorithm to address the faults. Simulation results on a benchmark B747 aircraft model demonstrate the effectiveness of the proposed fault-tolerant control.
INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING
(2023)
Article
Automation & Control Systems
Oscar Texis-Loaiza, Jaime A. Moreno, Leonid Fridman
Summary: This paper proposes a global, bi-homogeneous observer for a class of 1-DOF mechanical systems with various forces and frictions, along with bounded uncertainties/perturbations. The observer guarantees a predefined upper bound of convergence time and options for convergence acceleration are discussed in a simulation example.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Construction & Building Technology
Ennia Mariapaola Acerra, Murad Shoman, Hocine Imine, Claudia Brasile, Claudio Lantieri, Valeria Vignali
Summary: Cyclist safety is crucial due to the increasing use of bicycles as a means of transportation. This study highlights the critical points of infrastructure and interactions with different road users through visual tracking and a bicycle simulator. A comparison between real tests and simulations reveals objective differences in behavior and a low workload perception by cyclists.
Article
Engineering, Mechanical
Murad Shoman, Hocine Imine
Summary: This paper focuses on studying the needs and interactions of people with disabilities when interacting with cyclists. The study uses an online questionnaire and an on-road experiment to evaluate the possibility of sharing cycling infrastructure with wheelchair users. The results indicate that people with disabilities feel threatened by cyclists sharing the sidewalk and suggest keeping the sidewalk free of cyclists to avoid conflict. The experiment shows positive feedback from wheelchair users regarding the improvement of speed and safety when sharing cycling infrastructure.
Article
Automation & Control Systems
David Gomez-Gutierrez, Rodrigo Aldana-Lopez, Richard Seeber, Marco Tulio Angulo, Leonid Fridman
Summary: Existing differentiation algorithms are limited to signals with nth order Lipschitz derivative. This article presents a general methodology using time-varying gains to design nth order differentiators with a predefined Upper Bound on the Settling Time (UBST) for a broader class of signals whose (n + 1)th derivative is bounded by a function with bounded logarithmic derivative. Compared to existing methods, our approach maintains exact convergence using bounded gains and improves performance under measurement noise by considering a compact set of initial conditions.
Article
Automation & Control Systems
Ulises Perez-Ventura, Jonathan Escobar, Leonid Fridman, Rafael Iriarte
Summary: This paper proposes a design methodology for the second-order robust exact differentiator in the presence of small time-delays in signal processing. It uses the describing function to provide multiple sets of gains that ensure high accuracy in reconstructing the first-order derivative of smooth signals and minimizing the main harmonic of chattering. The proposal fulfills Loeb's criterion and proves the global finite-time stability of the non-delayed differentiator using a homogeneous Lyapunov function. Numerical examples are provided to illustrate the results.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Automation & Control Systems
Rosalba Galvan-Guerra, Gian Paolo Incremona, Leonid Fridman, Antonella Ferrara
Summary: This letter presents a novel optimal control approach for systems represented by a multi-model, where each model corresponds to a different operating point. The proposed method combines model predictive control (MPC) and first-order integral sliding mode control to reject uncertainty and ensure the controlled system behaves like the nominal multi-model. The MPC design is also optimized for limited computational complexity to facilitate practical applicability. Simulation results demonstrate the effectiveness of the proposed control approach.
IEEE CONTROL SYSTEMS LETTERS
(2022)
