Isola in a linear one-degree-of-freedom feedback system with actuator rate saturation  

作　　者：Duc H.Nguyen Thomas L.Hill Mark H.Lowenberg 

机构地区：[1]Faculty of Engineering,University of Bristol,Bristol,UK

出　　处：《International Journal of Mechanical System Dynamics》2023年第3期186-191,共6页国际机械系统动力学学报（英文）

摘　　要：This short communication uses numerical continuation to highlight the existence of an isola in a simple one-degree-of-freedom harmonically forced feedback system with actuator rate limiting as its only nonlinear element.It was found that the isola(1)contains only rate-limited responses,(2)merges with the main branch when the forcing amplitude is sufficiently large,and(3)includes stable solutions that create a second attractor in regions where rate limiting is not expected.Furthermore,the isola is composed of two solutions for a given forcing frequency.These solutions have the same amplitudes in the state(pitch rate)projection;however,they have distinct phases,and their amplitudes are also distinct when projected onto the integrator state in the controller.The rich dynamics observed in such a simple example underlines the impact of rate limiting on feedback systems.Specifically,the combination of feedback and rate limiting can create detrimental dynamics that is hard to predict and requires careful analysis.

关 键 词：frequency response harmonic forcing rate saturation isola dynamical system 

分 类 号：TP13[自动化与计算机技术—控制理论与控制工程]