Time-delay feedback control of an axially moving nanoscale beam with time-dependent velocity

Abstract

The paper is concerned with the nonlinear subharmonic resonance of an axially moving nanoscale beam with time-dependent velocity controlled by displacement and velocity time delay. To gain a thorough understanding of the system, the frequency response equation is first obtained using the multiple scales method. The stable intervals of the system's zero and non-zero solutions, as well as the necessary and sufficient conditions for Hopf bifurcation are specified. Then, the effects of nonlocal parameter, displacement feedback gain coefficient, velocity feedback gain coefficient, displacement and velocity time delay on the system's dynamic behaviors are discussed. The analysis demonstrates that the nonlocal parameters can not only reduce the amplitude of the system, but also change the stable regions of the non-zero solution. Furthermore, the time delay parameters can affect the number, amplitude, and stability of non-zero solutions. If the time delay parameters are chosen within the optimal value range, both positive and negative time delay feedback can effectively control system stability. These research results will serve as a theoretical reference for the design and optimization of axially moving nanostructures.