Optimization of the Mechanical Stability of a Centrifugal Microscope

Abstract

In this research I have studied the mechanical stability of a centrifugal force microscope (CFM). The CFM is used to study, among other things, the mechanical folding and unfolding of G-quadruplex DNA strands under high G-loads. These measurements require that the machine vibrations and other perturbations are brought to a maximum of 10 nm. I have characterized the vibrations of the stuck beads when rotating and calibrated the counterweight of the swing arm such that vibrations are reduced to a minimum when rotating at speeds up to 200 RPM. By measuring the movement of the stuck beads, I determined the amplitude of the vibrations at the tip of the swing arm. The main cause for vibrations proved to be the motor. The system proved to be stable and imbalance was only noticeable at speeds above 300 RPM.