Composite Adaptive Control for Time-Varying Systems With Dual Adaptation

• 成果类型: Article
• 署名作者: Goel, Raghavv; Roy, Sayan Basu
• 署名单位: Carnegie Mellon University
• 刊物名称: IEEE TRANSACTIONS ON AUTOMATIC CONTROL
• ISSN/ISSBN: 0018-9286
• DOI: 10.1109/TAC.2024.3433672
• 发表日期: 2025
• 页码: 487-494
• 关键词: Time-varying systems; Adaptive control; Parameter Estimation; CONVERGENCE; Heuristic algorithms; Perturbation methods; vectors; Adaptive systems; composite adaptive control; initial excitation (IE); persistence of excitation (PE); time-varying system

摘要

This article 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 toward a similar direction, where a novel dual adaptation mechanism is introduced to efficiently tackle the time-varying nature of the parameters. Projection and $\sigma$-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 boundedness of the closed-loop system with a tighter ultimate bound compared to existing results. 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.