Executive Summary : | This research aims to predict the ranges of mid-point deflections of initially curved microbeams or MEMS arches, which can retract back to their curved state when actuated electrically. The study will develop a modelling framework to extract the ranges on the initial midspan displacement of a curved microbeam, ensuring its retractability to the original configuration. The release phenomenon from the pull-in state will be modelled as a free vibration problem. The study will investigate the existence of successive bands on the initial displacement, which can take the beam to either of the equilibrium positions. The inferences could be helpful in designing MEM actuators employing bistable structures, such as arches and buckled beams. The optimum shape of arches will ensure the minimum/maximum force required to transition between states, and the effects of axial stress and support compliance on retractability bands will be explored. The geometry of the microactuator influences both mechanical stiffness and electrostatic force distribution, and exploitation of optimal changes to the geometry is a passive method used to enhance the performance of electrostatic microactuators. The research proposes building a shape optimization framework for MEMS arches and buckled microbeams, which will also influence the bounds of release positions and buckled microbeams' bistability nature. It is essential to predict the bounds on initial release positions of arches and their bistability characteristics, and the influences of their shape alterations on both phenomena. |