Electrothermomechanical modeling of out-of-plane deformation in single-stepped beams actuated by resistive heating

Abstract

An analytical model for the electrothermomechanical analysis of out-of-plane deformation in resistively heated single-stepped beams is presented. The model takes into account the conductive heat transfer from the beam to the substrate in which it is anchored. It also considers the temperature dependence of the beam material properties and accounts for the locally enhanced resistive heating effect around the release holes in the beam to predict temperature distribution along the beam. Energy method and Euler–Bernoulli beam theory are used for the prediction of out-of-plane deformation and stress distribution of the beam, as well as the out-of-plane rotation at the middle of the beam. The model considers the nonuniformity of the air gap between the beam and the substrate and captures the resultant asymmetric temperature distribution along the beam. The out-of-plane rotations in the middle of the single-stepped beam predicted by the analytical model and measured experimentally agree within 10%. The analytical model is then used to predict the maximum actuation current, which results in high temperature plastic deformation and agrees with the experiments within 5%. The proposed analytical model provides a good approach for systematic design and analysis of out-of-plane electrothermal microactuators based on single-stepped beam design.

Design, modeling and experimental validation of a micro cantilever beam with an electro-controllable twisting ability

“…But the design of its interdigitated electrodes makes the size of the whole beam reach the millimeter level that should be viewed as macro-level structure design. There is also a single-stepped beam, which is built to generate a slight torsion along the direction parallel to its short axis [16]. Even though two remote ends of this beam are anchored on the bases, its twisting axis is changed from the direction parallel to the long axis to the direction parallel to the short axis.…”

Design and simulation of an out-of-plane electrothermal microactuator

“…Its structure is quite simple for micro-scale fabrication. Ali et al [9] investigated an outof-plane electrothermal microactuators based on a single stepped beam. Due to its asymmetric structure, the fabrication process may require more steps.…”