Modeling and Optimization of Novel Actuators Produced by Solid Freeform Fabrication

The ability of Solid Freeform Fabrication (SFF) to produce complex piezoceramic architectures has enabled the development of novel designs for PZT actuators. Recently, it has been shown that through the intelligent application of actuator geometry, poling direction, piezoelectric material, and electric field direction, the force and displacement output of a piezoelectric actuator could be optimized. The current investigation examines several piezoceramic actuator geometries, including dome, spiral and a telescoping shaped actuators. Using finite element analysis (FEA), parametric studies are performed to identify some key issues in the optimization of actuator performance. Results of the dome study indicate that an actuator having a tangentially alternating poling direction and applied electric field exhibits a much larger displacement when compared to dome actuators having either a through-the-thickness or tangential poling direction. Analysis of spiral actuators indicates that the spiral geometry results in pronounced displacement amplification when compared to the displacement of an equivalent length piezoelectric strip. In summary, some remarks will be made on the optimal use of piezoelectric material properties and actuator geometry in actuator design.