ABSTRACT
This work presents a comprehensive model for nanobeams, incorporating beam curvature and surface energy. Gurtin-Murdoch surface stress theory is used, in conjunction with Euler-Bernoulli beam theory, to model the beams and take surface energy effects into consideration. The model was validated by contrasting its outcomes with experimental data published in the literature on the static bending of fixed-fixed and fixed-free nanobeams. The outcomes demonstrated that surface stress alters the stiffness of both fixed-fixed and fixed-free nanobeams with different behaviors in each case.
ABSTRACT
We experimentally investigate the primary superharmonic of order two and subharmonic of order one-half resonances of an electrostatic MEMS actuator under direct excitation. We identify the parameters of a one degree of freedom (1-DOF) generalized Duffing oscillator model representing it. The experiments were conducted in soft vacuum to reduce squeeze-film damping, and the actuator response was measured optically using a laser vibrometer. The predictions of the identified model were found to be in close agreement with the experimental results. We also identified the noise spectral density of process (actuation voltage) and measurement noise.
