Voltage-driven transverse vibration and dynamic stability of a spinning SWBNNT partially embedded in an elastic foundation

Electro-mechanical nanomachines represent a significant technological advancement in the development of next-generation nano-electromechanical systems (NEMS). This study investigates the complex rotodynamic behavior and electro-mechanical vibration of a novel CNT@BNNT@CNT nanomotor architecture. The system consists of a smart single-walled boron nitride nanotube (SWBNNT) acting as a spinning rotor, concentrically encased by carbon nanotubes (CNTs) that function as a fixed stator. To accurately capture the physics at the nanoscale, the stator's confinement effect is modeled as an advanced elastic foundation, while the spinning SWBNNT rotor is mathematically formulated using the Timoshenko beam theory incorporated with the Nonlocal Strain Gradient Theory (NSGT). The governing equations of motion, accounting for the gyroscopic effect, rotary inertia, shear deformation, and inverse piezoelectric effect, are derived via Hamilton's principle and solved using the Galerkin method. A comprehensive parametric study is conducted to evaluate the influence of Small-scale parameters The elastic foundation boundary conditions external electric voltage on the dynamic stability and whirling frequencies of the nanomotor.