AutomaticaPub Date : 2025-08-27DOI: 10.1016/j.automatica.2025.112550
Aditya Krishna Rao, Twinkle Tripathy
{"title":"Trajectory elongation strategies with minimum curvature discontinuities for a Dubins vehicle","authors":"Aditya Krishna Rao, Twinkle Tripathy","doi":"10.1016/j.automatica.2025.112550","DOIUrl":"10.1016/j.automatica.2025.112550","url":null,"abstract":"<div><div>In this paper, we present strategies for designing curvature-bounded trajectories of any desired length between any two given oriented points. The proposed trajectory is constructed by the concatenation of three circular arcs of varying radii. Such a trajectory guarantees a complete coverage of the maximum set of reachable lengths while minimising the number of changeover points in the trajectory to a maximum of two under all scenarios. Additionally by using the notion of internally tangent circles, we expand the set of Circle-Circle-Circle trajectories to eight kinds, consisting of <span><math><mrow><mo>{</mo><mi>L</mi><mi>L</mi><mi>L</mi><mo>,</mo><mi>L</mi><mi>L</mi><mi>R</mi><mo>,</mo><mi>L</mi><mi>R</mi><mi>R</mi><mo>,</mo><mi>L</mi><mi>R</mi><mi>L</mi><mo>,</mo><mi>R</mi><mi>R</mi><mi>L</mi><mo>,</mo><mi>R</mi><mi>L</mi><mi>L</mi><mo>,</mo><mi>R</mi><mi>L</mi><mi>R</mi><mo>,</mo><mi>R</mi><mi>R</mi><mi>R</mi><mo>}</mo></mrow></math></span> paths. The paper presents a mathematical formulation of the proposed trajectory and the conditions for the existence and classification of each kind of trajectory. We also analyse the variation of the length of the trajectory using suitable elongation strategies and derive the set of reachable lengths for all pairs of oriented points. Moreover, we highlight the conditions required for the existence of multiple trajectories of any feasible desired length Finally, the results of this paper are illustrated using numerical simulations.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112550"},"PeriodicalIF":5.9,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144902488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-27DOI: 10.1016/j.automatica.2025.112567
Fernando Castaños , Félix Miranda-Villatoro , Bernard Brogliato
{"title":"Multivalued Hamiltonian systems with sliding motions: Analysis of the backward-Euler discretisation","authors":"Fernando Castaños , Félix Miranda-Villatoro , Bernard Brogliato","doi":"10.1016/j.automatica.2025.112567","DOIUrl":"10.1016/j.automatica.2025.112567","url":null,"abstract":"<div><div>This article is mainly concerned with the time-discretisation of multivalued Hamiltonian systems with multivalued dissipation, a special class of differential inclusions. Two classes of set-valued Hamiltonian systems are considered, depending on whether the dissipation function is position- or momentum-dependent. The backward-Euler discretisation is analysed in both cases: the well-posedness of the generalised equation obtained after discretisation is proved, and then finite-time stability of fixed points is tackled. The well-known twisting and super-twisting sliding-mode algorithms, as well as an example from Contact Mechanics and dynamical optimisation, illustrate the theoretical developments.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112567"},"PeriodicalIF":5.9,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144902489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-27DOI: 10.1016/j.automatica.2025.112549
Hao Luo , Shimeng Wu , Linlin Li
{"title":"A time-domain estimation of the ν-gap metric and stability margin with its application to attack defense in cyber-physical systems","authors":"Hao Luo , Shimeng Wu , Linlin Li","doi":"10.1016/j.automatica.2025.112549","DOIUrl":"10.1016/j.automatica.2025.112549","url":null,"abstract":"<div><div>To address the limitations of model-based moving target defense (MTD) scheme against stealthy attacks in cyber–physical systems, this paper proposes a novel data-driven MTD (DD-MTD)approach based on the <span><math><mi>ν</mi></math></span>-gap metric and the stability margin. To design and implement the traditional model-based MTD in a data-driven framework, the <span><math><mi>ν</mi></math></span>-gap metric and the stability margin are estimated in the time domain under the plug-and-play process monitoring and control architecture (PnP-PMCA). Besides, the anomaly detector based on the <span><math><mi>ν</mi></math></span>-gap metric aids in distinguishing between faults and stealthy attacks. As an essential part of this study, the stable image representation (SIR) and kernel representation (SKR) are identified using real-time closed-loop data. The proposed approaches are verified via a numerical example and a test on the Mecanum-wheeled mobile robot.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112549"},"PeriodicalIF":5.9,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144902638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-27DOI: 10.1016/j.automatica.2025.112517
Mario Sperl, Jonas Mysliwitz, Lars Grüne
{"title":"On the existence and neural network representation of separable control Lyapunov functions","authors":"Mario Sperl, Jonas Mysliwitz, Lars Grüne","doi":"10.1016/j.automatica.2025.112517","DOIUrl":"10.1016/j.automatica.2025.112517","url":null,"abstract":"<div><div>In this paper, we investigate the ability of neural networks to mitigate the curse of dimensionality in representing control Lyapunov functions. To achieve this, we first prove an error bound for the approximation of separable functions with neural networks. Subsequently, we discuss conditions on the existence of separable control Lyapunov functions, drawing upon tools from nonlinear control theory. This enables us to bridge the gap between neural networks and the approximation of control Lyapunov functions. Moreover, we present a network architecture and a training algorithm to illustrate the theoretical findings on a 10-dimensional control system.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112517"},"PeriodicalIF":5.9,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144902554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-26DOI: 10.1016/j.automatica.2025.112521
Wei Huo , Xiaomeng Chen , Lingying Huang , Karl Henrik Johansson , Ling Shi
{"title":"Differentially private dual gradient tracking for distributed resource allocation","authors":"Wei Huo , Xiaomeng Chen , Lingying Huang , Karl Henrik Johansson , Ling Shi","doi":"10.1016/j.automatica.2025.112521","DOIUrl":"10.1016/j.automatica.2025.112521","url":null,"abstract":"<div><div>This paper investigates privacy issues in distributed resource allocation over directed networks, where each agent holds a private cost function and optimizes its decision subject to a global coupling constraint through local interaction with other agents. Conventional methods for resource allocation over directed networks require all agents to transmit their original data to neighbors, which poses the risk of disclosing sensitive and private information. To address this issue, we propose an algorithm called differentially private dual gradient tracking (DP-DGT) for distributed resource allocation, which obfuscates the exchanged messages using independent Laplacian noise. Our algorithm ensures that the agents’ decisions converge to a neighborhood of the optimal solution almost surely. Furthermore, without the assumption of bounded gradients, we prove that the cumulative differential privacy loss under the proposed algorithm is finite even when the number of iterations goes to infinity. To the best of our knowledge, we are the first to simultaneously achieve these two goals in distributed resource allocation problems over directed networks. Finally, numerical simulations on economic dispatch problems within the IEEE 14-bus system illustrate the effectiveness of our proposed algorithm.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112521"},"PeriodicalIF":5.9,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144896006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-25DOI: 10.1016/j.automatica.2025.112504
Arthur Castello B. de Oliveira , Milad Siami , Eduardo D. Sontag
{"title":"Convergence analysis of gradient flow for overparameterized LQR formulations","authors":"Arthur Castello B. de Oliveira , Milad Siami , Eduardo D. Sontag","doi":"10.1016/j.automatica.2025.112504","DOIUrl":"10.1016/j.automatica.2025.112504","url":null,"abstract":"<div><div>This paper analyzes the intersection between results from gradient methods for the model-free linear quadratic regulator (LQR) problem, and linear feedforward neural networks (LFFNNs). More specifically, it looks into the case where one wants to find an LFFNN feedback that minimizes an LQR cost. It starts by deriving a key conservation law of the system, which is then leveraged to generalize existing results on boundedness and global convergence of solutions, and invariance of the set of stabilizing LFFNNs under the training dynamics (gradient flow). For the single hidden layer LFFNN, the paper proves that the solution converges to the optimal feedback control law for all but a set of Lebesgue measure zero of the initializations. These results are followed by an analysis of a simple version of the problem – the “vector case” – proving the theoretical properties of accelerated convergence and a type of input-to-state stability (ISS) result for this simpler example. Finally, the paper presents numerical evidence of faster convergence of the gradient flow of general LFFNNs when compared to non-overparameterized formulations, showing that the acceleration of the solution is observable even when the gradient is not explicitly computed, but estimated from evaluations of the cost function.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112504"},"PeriodicalIF":5.9,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144893836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-23DOI: 10.1016/j.automatica.2025.112547
Ana Sánchez-Amores , Antonio Ferramosca , José M. Maestre , Eduardo F. Camacho
{"title":"Partially cooperative robust distributed model predictive control for tracking","authors":"Ana Sánchez-Amores , Antonio Ferramosca , José M. Maestre , Eduardo F. Camacho","doi":"10.1016/j.automatica.2025.112547","DOIUrl":"10.1016/j.automatica.2025.112547","url":null,"abstract":"<div><div>This work investigates a partially-cooperative coalitional control setting for input-coupled multi-agent linear systems to robustly track changing setpoints. Within this framework, agents have the flexibility to share a public portion of their input, ceding control authority to neighbors, while keeping the rest private. Instead of coordinating the predicted control inputs, the bounds that define the public and private input constraint sets are negotiated in a distributed manner when the need arises, significantly reducing communicated data within the cooperation network. Coupling disturbances are considered through a tube-based approach, which steers the system to the desired target points while guaranteeing recursive feasibility and stability through tracking techniques. Finally, the approach is validated through simulations on an eight-input coupled tank benchmark.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112547"},"PeriodicalIF":5.9,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-23DOI: 10.1016/j.automatica.2025.112526
Diego dos Santos Carneiro , Flávio Andrade Faria , Vilma Alves de Oliveira , Michele Cucuzzella , Antonella Ferrara
{"title":"Observer-based detection and isolation of permanent sensor faults in a class of uncertain switched affine systems","authors":"Diego dos Santos Carneiro , Flávio Andrade Faria , Vilma Alves de Oliveira , Michele Cucuzzella , Antonella Ferrara","doi":"10.1016/j.automatica.2025.112526","DOIUrl":"10.1016/j.automatica.2025.112526","url":null,"abstract":"<div><div>This paper develops a robust fault detection and isolation (FDI) strategy for a class of uncertain continuous-time switched affine systems when the system state is not fully available for measurement, and all system sensors are prone to permanent abrupt bounded faults. The FDI strategy is obtained by designing a number of FDI devices equal to the number of sensors. First, we give linear matrix inequalities conditions to design a bank of full-state Luenberger observers in a pseudo-dedicated scheme with guaranteed <span><math><msub><mrow><mi>S</mi></mrow><mrow><mo>−</mo></mrow></msub></math></span> and <span><math><msub><mrow><mi>L</mi></mrow><mrow><mi>∞</mi></mrow></msub></math></span> performances to work as residual error generators (REGs). In the sequence, considering an extension of the concepts of weak and strong detectability and novel concepts of weak and strong isolation, residual evaluation functions are defined, and threshold functions are designed considering the gains and parameters obtained in the REG design, taking into consideration the smallest fault magnitude to be detected to achieve a mixed <span><math><mrow><msub><mrow><mi>S</mi></mrow><mrow><mo>−</mo></mrow></msub><mo>/</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>∞</mi></mrow></msub></mrow></math></span> performance. An Algorithm to determine a piecewise constant threshold function is proposed to obtain less conservative constraints in the optimization problem. Furthermore, parameter-tuning algorithms are proposed to obtain local optima thresholds and REGs to satisfy weak isolation conditions over a range of uncertainties. Finally, a Cuk DC–DC converter is considered to demonstrate the effectiveness of the proposed approach.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112526"},"PeriodicalIF":5.9,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AutomaticaPub Date : 2025-08-23DOI: 10.1016/j.automatica.2025.112529
Songlin Yang, Sorin Olaru, Pedro Rodriguez-Ayerbe
{"title":"Lifting-based PWA control: A global solution to handle disturbances in the state space partitions","authors":"Songlin Yang, Sorin Olaru, Pedro Rodriguez-Ayerbe","doi":"10.1016/j.automatica.2025.112529","DOIUrl":"10.1016/j.automatica.2025.112529","url":null,"abstract":"<div><div>This paper presents a global strategy to address the robustness and fragility of Piecewise Affine (PWA) control, which arises from geometrical perturbations in state-space partitions. Existing methods, which handle perturbations using vertex-based or halfspace-based region representations, are limited to local adjustments of vertices or hyperplanes. In contrast, this paper introduces a novel convex lifting-based region representation that accounts for all subregions of the PWA control perturbation simultaneously. An optimization-based approach is then proposed to enhance the robustness or fragility of the nominal PWA control by refining the lifting-based representation. A numerical example illustrates the effectiveness of the proposed framework.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112529"},"PeriodicalIF":5.9,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Adaptive prescribed-time control for nonlinear cascade systems with FxT-ISS inverse dynamics","authors":"Jiangbo Yu , Chengdong Li , Zhengtao Ding , Yuqiang Wu","doi":"10.1016/j.automatica.2025.112527","DOIUrl":"10.1016/j.automatica.2025.112527","url":null,"abstract":"<div><div>In this paper we consider the adaptive prescribed-time control problem for nonlinear cascade systems with unmeasured inverse dynamics and nonlinearly parametric uncertainty. Thanks to the notions of fixed-time input-to-state stability/stable (FxT-ISS) and FxT-ISS Lyapunov functions to characterize the system of inverse dynamics, we present a two-stage prescribed-time control scheme, which ensures that the system states reach the origin and keep afterwards within the prescribed-time instant. Different from the adaptive prescribed-time control schemes in literatures, we develop a novel theoretical tool to determine the prescribed-time stability via time-varying partial-state feedback in this paper. The proposed control scheme is illustrated by means of the prescribed-time set-point tracking control in a pendulum system.</div></div>","PeriodicalId":55413,"journal":{"name":"Automatica","volume":"182 ","pages":"Article 112527"},"PeriodicalIF":5.9,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}