Thermal cycle modeling of electrothermal microactuators

A methodology for computing the transient heating (charging) and cooling (discharging) time for a serially connected electro thermo (E-T) microbeams actuator were analytically approximated from fundamental characteristics including input voltage, material and geometry. Specifically, this paper presents closed form solutions for folded and bend beam MEMS actuators. The E-T heating time was obtained from the simplified transient heat conduction equations using a trial solution method combined with the Laplace domain based on polynomial shape function, while the cooling response of thermal actuator is derived from steady state temperature distribution. The proposed approximate methods are utilized in illustrative examples and validated by Finite Difference Approximation (FDA), and Finite Element Modeling (FEM).