This paper proposes a composite adaptive control architecture using dual adaptation scheme for dynamical systems comprising time-varying uncertain parameters. While majority of the adaptive control schemes in literature address the case of constant parameters, recent research has conceptualized improved adaptive control techniques for time-varying systems with rigorous stability proofs. The proposed work is an effort towards a similar direction, where a novel dual adaptation mechanism is introduced to efficiently tackle the time-varying nature of the parameters. Projection and $σ$-modification algorithms are strategically combined using congelation of variables to claim a global result for the tracking error space. While the classical adaptive systems demand a restrictive condition of persistence of excitation (PE) for accurate parameter estimation, the proposed work relies on a milder condition, called initial excitation (IE) for the same. A rigorous Lyapunov stability analysis is carried out to establish uniformly ultimately bounded (UUB) stability of the closed-loop system. Further it is analytically shown that the proposed work can recover the performance of previously designed IE-based adaptive controller in case of time invariant systems.
Safe Control of Quadruped in Varying Dynamics via Safety Index Adaptation
Mechanical Engineering Department, Carnegie Mellon University（卡内基梅隆大学机械工程系）；Robotics Institute, Carnegie Mellon University（卡内基梅隆大学机器人研究所）；Mechanical Engineering Department, New Mexico Institute of Mining and Technology（新墨西哥州矿业与技术研究所机械工程系）
Intelligent Domain Adaptation for Power System Transient Stability Assessment Under Varying Operating Scenarios
National Graduate College for Elite Engineers, Hunan University（湖南大学国家精英工程师研究生院）；College of Electrical and Information Engineering, Hunan University（湖南大学电气与信息工程学院）
Three High Performance Global Tracking Composite Adaptive Controllers for Fully Actuated Euler-Lagrange Systems: Experimental Validation
Tecnológico Nacional de México / I. T. de La Laguna（墨西哥国立理工学院拉古纳信息技术学院）；Departamento de Ingeniería Eléctrica y Electrónica /Instituto Tecnológico Autónomo de México（墨西哥自治理工学院电气与电子工程系）；Tecnológico Nacional de México / I. T. de La Paz（墨西哥国立理工学院拉巴斯信息技术学院）
Composite Adaptive Control for Bilateral Teleoperation Systems without Persistency of Excitation
School of Automation and Electrical Engineering, University of Science and Technology Beijing（自动化与电气工程学院，北京科技大学）；Department of Automatic Control, Lund University, P.O. Box 118, 22100 Lund, Sweden（自动控制系，卢德大学）
