-
作者：Nazarzadeh, Amin; Marquez, Horacio J.
作者单位：University of Alberta
摘要：The literature shows that the discretization in sampled-data systems can create unstable zero-dynamics, making the system vulnerable to cyber-attacks. We study input-to-state stability (ISS) of nonlinear event-based control systems under zero-dynamics attacks. As a secure approach, we propose a novel multiobjective event-triggered mechanism that uses current measurements and a history of zero-dynamics for resilient triggering design. We derive sufficient conditions based on ISS and triggering ...
-
作者：Wang, Chenchao; Meng, Deyuan
作者单位：Beihang University; Beihang University
摘要：This article proposes basic definitions of similarity between heterogeneous linear systems, and develops a behavioral approach to address similarity-based learning and control problems for them. By exploring geometric properties of admissible behaviors of linear systems, the similarity indexes between admissible behaviors of heterogeneous systems are defined thanks to the principal angles between subspaces. Moreover, an efficient strategy for calculating the similarity indexes is presented, ba...
-
作者：Zhao, Feiran; You, Keyou
作者单位：Tsinghua University; Tsinghua University
摘要：In safety-critical applications, reinforcement learning (RL) needs to consider safety constraints. However, theoretical understandings of constrained RL for continuous control are largely absent. As a case study, this article presents a cost-constrained linear-quadratic regulator (LQR) formulation, where a number of LQR costs with user-defined penalty matrices are subject to constraints. To solve it, we propose a policy gradient (PG) primal-dual method to find an optimal state feedback gain. D...
-
作者：Khong, Sei Zhen; Hara, Shinji; Lanzon, Alexander
作者单位：National Sun Yat Sen University; Institute of Science Tokyo; Tokyo Institute of Technology; University of Manchester
摘要：We introduce the notions of negative imaginariness input and output indices for describing systems that do not manifest the negative imaginary (NI) property on certain frequency bands, thereby characterizing classes of linear time-invariant systems that are larger than those of negative imaginary systems without poles at the origin. We show that if the total frequency-dependent negative imaginariness in a feedback interconnection is positive as measured by the NI indices, whereby any deficienc...
-
作者：Zhou, Tong
作者单位：Tsinghua University
摘要：Time-domain identification is studied in this article for parameters of a continuous-time multi-input multi-output descriptor system, with these parameters affecting system matrices through a linear fractional transformation. Sampling is permitted to be nonuniform and slow, in the sense that it is not required to satisfy the Nyquist frequency restrictions. This model can be used to describe the behaviors of a networked dynamic system, and the obtained results can be straightforwardly applied t...
-
作者：Deutscher, Joachim; Enderes, Tarik
作者单位：Ulm University
摘要：This article is concerned with the data-driven stabilization of unknown boundary controlled semilinear parabolic systems. The nonlinear dynamics of the system are lifted using a finite number of eigenfunctionals of the Koopman operator related to the autonomous semilinear PDE. This results in a novel data-driven finite-dimensional model of the lifted dynamics, which is amenable to apply design procedures for finite-dimensional systems to stabilize the semilinear parabolic system. In order to f...
-
作者：Williams, Daniel A.; Chapman, Airlie; Manzie, Chris
作者单位：University of Melbourne; University of Melbourne
摘要：Inspired by the increased cooperation between humans and autonomous systems, we present a new hybrid systems framework capturing the interconnected dynamics underlying these interactions. The framework accommodates models arising from both the autonomous systems and cognitive psychology literature in order to represent key elements, such as human trust, in the autonomous system. The intermittent nature of human interactions are incorporated by asynchronous event-triggered sampling at the frame...
-
作者：Hu, Zhongjie; De Persis, Claudio; Tesi, Pietro
作者单位：University of Groningen; University of Florence
摘要：We present data-based conditions for enforcing contractivity via feedback control and obtain desired asymptotic properties of the closed-loop system. We focus on unknown nonlinear control systems whose vector fields are expressible via a dictionary of functions and derive data-dependent semidefinite programs whose solution returns the controller that guarantees contractivity. When data are perturbed by disturbances that are linear combinations of sinusoids of known frequencies (but unknown amp...
-
作者：Almubarak, Hassan; Sadegh, Nader; Theodorou, Evangelos A.
作者单位：King Fahd University of Petroleum & Minerals; University System of Georgia; Georgia Institute of Technology; University System of Georgia; Georgia Institute of Technology
摘要：Multiobjective safety-critical control entails a diligent design to avoid possibly conflicting scenarios and ensure safety. This article addresses multiobjective safety-critical control through a novel approach utilizing barrier states to integrate safety into control design. It introduces the concept of safety embedded systems, where the safety condition is integrated with barrier functions to characterize a dynamical subsystem that is incorporated into the original model for control design. ...
-
作者：Cai, Songfu; Cao, Xuanyu
作者单位：Zhejiang University; Washington State University
摘要：We consider a wireless networked control system with multiple controllers and multiple attackers. The dynamic interaction between the controllers and the attackers is modeled as a linear quadratic (LQ) zero-sum difference game with multiplicative randomness induced by the the multiple-input and multiple-output (MIMO) wireless fading. The existence of the game value is of significant importance to the LQ zero-sum game. If it exists, the value characterizes the minimum loss that the controllers ...
