{"title":"Design and validation of new discrete-time kinematic control scheme for physically-constrained redundant robot manipulators","authors":"Zuoli Ye, Shukang Chen, Naimeng Cang, Xiyuan Zhang, Dongsheng Guo, Weidong Zhang","doi":"10.1016/j.ejcon.2025.101398","DOIUrl":"10.1016/j.ejcon.2025.101398","url":null,"abstract":"<div><div>Kinematic control is one of the fundamental issues of redundant robot manipulators with joint physical constraints. In this paper, a new kinematic control scheme with discrete-time form is proposed for physically-constrained redundant robot manipulators. Specifically, with joint limits considered, the kinematic control of redundant robot manipulators is formulated as a linear system consisting of kinematic equation and inequality. Then, by designing a neural-dynamics model to solve such a system and by utilizing the Euler difference rule, the new discrete-time kinematic control (DTKC) scheme is thus established. Simulation results under the constrained UR5 and PA10 robot manipulators with path tracking, repetitive motion, and obstacle avoidance examples further validate the effectiveness of the proposed DTKC scheme. The DTKC applicability is finally indicated by implementing the proposed scheme on the practical E6 robot manipulator.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101398"},"PeriodicalIF":2.6,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhipeng Zhang , Aocheng Wang , Haitao Li , Chengyi Xia
{"title":"Algebraic calculation for safety synthesis of networked logical finite state machines","authors":"Zhipeng Zhang , Aocheng Wang , Haitao Li , Chengyi Xia","doi":"10.1016/j.ejcon.2025.101386","DOIUrl":"10.1016/j.ejcon.2025.101386","url":null,"abstract":"<div><div>This paper investigates the safety synthesis problem of networked logical finite state machines with bounded communication delays in observation and control channels using the semi-tensor product (STP) of matrices. First, algebraic formulations for networked state estimation and state prediction are constructed. By defining a set of critical states that may transition to illegal states through observable events under communication delays, a more refined algorithm for state evolution is proposed. Then, based on the concept of minimal constraints, necessary and sufficient algebraic conditions are derived for the existence of a networked supervisor that satisfies the given safety specifications. The proposed method exhibits polynomial time complexity. Finally, the theoretical results are validated through an illustrative example.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101386"},"PeriodicalIF":2.6,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A widely-practical model-free prescribed time control for trajectory tracking of n-DOF robot manipulators","authors":"Chems Eddine Boudjedir","doi":"10.1016/j.ejcon.2025.101396","DOIUrl":"10.1016/j.ejcon.2025.101396","url":null,"abstract":"<div><div>This paper proposes a novel, practical prescribed-time control (PTC) scheme for the trajectory tracking of n-degree-of-freedom (n-DOF) robot manipulators subject to external disturbances. Unlike existing approaches, the proposed PTC scheme is entirely model-free. It leverages a time-delay estimation (TDE) technique to compensate for unknown dynamics and disturbances, eliminating the need for upper bounds. A key innovation is the design of a new time-varying gain which increases only as the time approaches the prescribed value. This ensures the feasibility of the control signal and avoids saturation issues which often make practical deployment difficult. The controller also remains effective beyond the prescribed time, overcoming a significant limitation of previous studies. Rigorous Lyapunov analysis guarantees that position and velocity tracking errors will converge within the prescribed time. Comparative simulations on a parallel Delta robot demonstrate the superiority and practicality of the scheme over existing methods.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101396"},"PeriodicalIF":2.6,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exponential admissibility and H∞ controller design for continuous-time nonlinear time-varying delay singular systems","authors":"Le Van Hien , Le Huy Vu","doi":"10.1016/j.ejcon.2025.101374","DOIUrl":"10.1016/j.ejcon.2025.101374","url":null,"abstract":"<div><div>This paper focuses on the problem of exponential admissibility and <span><math><msub><mrow><mi>H</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> controller design for continuous-time nonlinear time-varying delay singular systems (CTN-TVD-SSs). By formulating a set of enhanced Lyapunov–Krasovskii functionals, new delay-dependent conditions are established using linear matrix inequality (LMI) settings to guarantee the regularity, impulse-freeness, and exponential admissibility with an <span><math><msub><mrow><mi>H</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> performance level <span><math><mi>γ</mi></math></span> of the closed-loop system. A state feedback <span><math><msub><mrow><mi>H</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> controller (SF-<span><math><msub><mrow><mtext>H</mtext></mrow><mrow><mi>∞</mi></mrow></msub></math></span>C) design is also discussed. Numerical examples with simulations are provided to illustrate the effectiveness of the obtained results.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101374"},"PeriodicalIF":2.6,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alireza Besharati , Afshin Taghvaeipour , Ali Kamali E. , Mohammad Zareinejad
{"title":"Assist-as-needed control of a soft rehabilitation robot for the finger using an interaction torque observer","authors":"Alireza Besharati , Afshin Taghvaeipour , Ali Kamali E. , Mohammad Zareinejad","doi":"10.1016/j.ejcon.2025.101395","DOIUrl":"10.1016/j.ejcon.2025.101395","url":null,"abstract":"<div><div>This paper introduces an Assist-as-Needed (AAN) control strategy for a soft finger rehabilitation robot using a fiber-reinforced bending (FRB) actuator. Most conventional rehabilitation controllers focus solely on position or force control and fail to incorporate the patient’s active participation during the rehabilitation process. This lack of engagement limits the effectiveness of patient-specific rehabilitation, highlighting the need for interaction-based strategies. To address this gap, we propose a novel AAN approach that combines a nonlinear disturbance observer (NDO) and a sliding mode controller (SMC), designed using the dynamic model of the FRB actuator. The NDO estimates the patient–robot interaction torque in real-time without using external sensors or modeling the patient’s finger, while the SMC ensures robust and accurate position tracking. This interaction-based assistance enables the system to dynamically adjust the level of assistance based on the patient’s voluntary efforts, while the controller simultaneously works to guide the finger movement toward the rehabilitation trajectory, promoting a more active and patient-specific rehabilitation process. Additionally, the stability of the closed-loop system is analytically proven using Lyapunov theory. The proposed method is validated both on a finger-like mechanism simulating various patient scenarios and on a wearable rehabilitation glove used by a participant. Experimental results confirm that the AAN controller achieves superior trajectory tracking and provides adaptive assistance aligned with the patient’s capability, outperforming conventional model-free controllers.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101395"},"PeriodicalIF":2.6,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yong Sun , Yiming Sun , Ruifei Peng , Chunhe Song , Qingxin Li , Shimao Yu , Yuqi Liu
{"title":"Optimization of robotic shaping control for non-rigid material with safety constraints","authors":"Yong Sun , Yiming Sun , Ruifei Peng , Chunhe Song , Qingxin Li , Shimao Yu , Yuqi Liu","doi":"10.1016/j.ejcon.2025.101394","DOIUrl":"10.1016/j.ejcon.2025.101394","url":null,"abstract":"<div><div>Robotic milling has emerged as a prominent research area for complex shaping owing to the inherent flexibility of manipulators. The investigation of robotic milling for rigid material has widely reported. However,because of the inherent attribute of rigid material, these methods mainly concentrate on the position and pose control of manipulators during task processing, lacking of reaction to material state, such as temperature and elastic deformation. This oversight becomes problematic when dealing with nonrigid materials since milling objectives are highly sensitive to changes in temperature and deformation. As a consequence, current robotic milling approaches designed for rigid materials may fail to ensure processing accuracy and security in such scenarios. To deal with this issue, this paper constructs a robotic milling simulation environment that incorporates a joint multi-fidelity surrogate model for nonrigid material milling with the consideration of temperature and deformation information. By means of reinforcement learning strategies to learn the knowledge of nonrigid material milling process, the elastic deformation can be effectively compensated and the temperature can be restricted within the preset bound while ensuring the processing efficiency. Finally, the effectiveness of the proposed control approach for nonrigid material milling is verified through simulation and experiment results.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101394"},"PeriodicalIF":2.6,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Information transfer and its control in linear discrete stochastic systems","authors":"Moirangthem Sailash Singh , Ramkrishna Pasumarthy , Umesh Vaidya , Steffen Leonhardt","doi":"10.1016/j.ejcon.2025.101392","DOIUrl":"10.1016/j.ejcon.2025.101392","url":null,"abstract":"<div><div>Information transfer is defined as a measure of the causal inferences between dynamical events. We quantify information transfers and study their responses to interventions or external signals within components of linear discrete stochastic systems. To quantify the causal inferences, we find the difference between the rate of change in the differential entropy of a marginal measure at a given coordinate in the presence and absence of another fixed coordinate. We also integrate theories from optimal control and information theory to compute control signals that result in desired information transfers within the dynamical components. To optimally steer the information transfer to the desired value, we convert the control problem into a nonlinear program, which can be solved numerically. We illustrate our theory with an example of a wireless communication system consisting of various transmitters and receivers. In particular, given a well-defined transmission channel model and the noise, we show that the signal-to-interference-plus-noise ratio, SINR of a receiver due to interference from various transmitters is a function of information transfers to the receiver from the transmitters, and controlling these transfers to desired values aligns with controlling the SINR experienced by the receiver.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101392"},"PeriodicalIF":2.6,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Saurabh R. Madankar , Amit Setia , Muniyasamy M. , Ravi P. Agarwal
{"title":"Haar wavelet-based Galerkin method with its feasibility, consistency, and application to unmanned vehicle navigation around moving obstacles","authors":"Saurabh R. Madankar , Amit Setia , Muniyasamy M. , Ravi P. Agarwal","doi":"10.1016/j.ejcon.2025.101393","DOIUrl":"10.1016/j.ejcon.2025.101393","url":null,"abstract":"<div><div>In this study, we propose a novel Haar wavelet-based Galerkin method to solve nonlinear optimal control problems with applications to unmanned vehicle navigation. The method addresses the critical challenge of optimizing energy consumption while ensuring safe navigation in dynamic environments with multiple moving obstacles. By leveraging the computational efficiency and scalability of Haar wavelets, combined with the robustness of the Galerkin approach, we demonstrate convergence to the optimal solution under feasibility and consistency conditions. Comprehensive numerical simulations, including diverse and complex obstacle scenarios, validate the method’s practicality. Through detailed trajectory, speed, and direction analyses, we highlight the approach’s ability to adapt to real-world navigation challenges, making it a promising tool for autonomous system optimization.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101393"},"PeriodicalIF":2.6,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emanuel C. Brenag , Paulo S.P. Pessim , Pedro M. Oliveira , Reinaldo M. Palhares
{"title":"Quasi-data-driven static output feedback control of linear systems with input and state delays","authors":"Emanuel C. Brenag , Paulo S.P. Pessim , Pedro M. Oliveira , Reinaldo M. Palhares","doi":"10.1016/j.ejcon.2025.101385","DOIUrl":"10.1016/j.ejcon.2025.101385","url":null,"abstract":"<div><div>This paper presents a quasi-data-driven static output feedback (SOF) control framework for discrete-time linear systems subject to time-varying state and input delays. The proposed controller synthesis leverages input-state-output data acquired from the open-loop system, integrated with delay-dependent data-based Linear Matrix Inequality (LMI) conditions derived using Lyapunov–Krasovskii stability theory. A salient feature of this methodology is its ability to compute controller gains without prior knowledge of the system dynamics, thereby eliminating the dependence on explicit mathematical models. Furthermore, a data-driven reference-tracking input scheme is developed for time-delay systems, addressing piecewise-constant reference trajectories while guaranteeing asymptotic stability of the tracking error. The efficacy of the proposed approach is rigorously validated through numerical simulations and also experimental implementation on a twin-rotor system for pitch angle tracking, demonstrating robust performance in both theoretical and practical settings.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101385"},"PeriodicalIF":2.6,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Guaranteed collision avoidance for autonomous surface vehicles equipped with a LiDAR using a CLF-CBF-QP controller","authors":"Diogo Silva , Daniel Silvestre","doi":"10.1016/j.ejcon.2025.101377","DOIUrl":"10.1016/j.ejcon.2025.101377","url":null,"abstract":"<div><div>Safe autonomous navigation in marine environments remains challenging due to the need to simultaneously handle multiple dynamic obstacles, uncertain conditions, and the inherent complexity of vessel dynamics while maintaining both stability and safety guarantees. This paper introduces a High-Order Barrier Function and Control Lyapunov Function (HOBF-CLF) based controller for Autonomous Surface Vehicles navigating unknown environments. Using real-time LiDAR data and a clustering algorithm, the controller efficiently handles multiple obstacles by treating them as separate entities. The HOBF-CLF approach guarantees both safety and stability through real-time quadratic optimization. Simulations show it performs better when compared to a state-of-the-art Model Predictive Controller and some PID-based methods in terms of control effort and computational efficiency.</div></div>","PeriodicalId":50489,"journal":{"name":"European Journal of Control","volume":"86 ","pages":"Article 101377"},"PeriodicalIF":2.6,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}