Vbiration control for the primary resonance of a cantilever beam by a time delay state feedback

The primary resonance of a cantilever beam under state feedback control with a time delay is investigated. By means of the asymptotic perturbation method, two slow-flow equations on the amplitude and phase of the oscillator are obtained and external excitation-response and frequency-response curves are shown. Vibration control and high-amplitude response suppression can be performed with appropriate time delay and feedback gains. Moreover, energy considerations are used in order to investigate existence and characteristics of quasiperiodic modulated motion for the cantilever beam. It can be demonstrated that appropriate choices for the feedback gains and the time delay can exclude the possibility of modulated motion and reduce the amplitude peak of the primary resonance. Analytical results are verified with numerical simulations. (C) 2002 Elsevier Science Ltd. All rights reserved.