MEMS Electrothermal Actuator

3D Model

Working Principle

This asymmetric U-shaped thermal actuator consists of a narrow “hot” arm and a wider “cold” arm connected in series to an electrical circuit. When current flows through the actuator, Joule heating produces more heat in the narrow arm and results in greater thermal expansion compared to the wide arm.

FEM Simulation

1. Source File: Model extracted from Elmer’s non-GUI tutorial (.msh file), converted in a .vtu file using meshio
2. In FreeCAD, .vtu converted with FEM Mesh to Mesh + Draft Upgrade to obtain a reworkable .STEP, before remeshing it as a .unv
3. FEM simulation completed with Elmer FEM solver
4. Generated .vtu sequence opened in ParaView, two frames exported as .abc
5. Final animation in Blender using Shape Keys
6. GLB animation uploaded on Sketchfab