On modeling and computer simulation of an electro-thermally driven cascaded nickel micro-actuator

Modeling and finite element (FE) simulation of a multi-cell cascaded laser fabricated electro-thermal micro-actuator (ETMA) made of nickel is presented. The actuator's topology permits adding displacements of each individual cell in the cascade. A proper accounting for temperature-dependent parameters and material properties for the range above 300 degrees C (magnetic phase transition for nickel) is emphasised. The FE simulation is carried over the electric, thermal, and mechanical fields using one geometrical model. The computer simulation is integrated with experimental measurements to adjust the material characteristics, such as resistivity, and the model characteristics, such as convection, and in order to verify different phases of the FE analysis. The complexities of combining the above three different physical fields in the analysis, as well as the efficiency of FE modeling and procedures are discussed in detail. (C) 2005 Elsevier B.V. All rights reserved.