  The scanning electron microscope (SEM) recordings of dynamic
nano-electromechanical systems (NEMS) are difficult to analyze due to the noise
caused by low frame rate, insufficient resolution and blurriness induced by
applied electric potentials. Here, we develop an image processing algorithm
enhanced by the physics of the underlying system to track the motion of
buckling NEMS structures in the presence of high noise levels. The algorithm is
composed of an image filter, two data filters, and a nonlinear regression
model, which utilizes the expected form of the physical solution. The method
was applied to the recordings of a NEMS beam about 150 nm wide, undergoing
intra-and inter-well post-buckling states with a transition rate of
approximately 0.5 Hz. The algorithm can track the dynamical motion of the NEMS
and capture the dependency of deflection amplitude on the compressive force on
the beam. With the help of the proposed algorithm, the transition from
inter-well to intra-well motion is clearly resolved for buckling NEMS imaged
under SEM.
