Force-deflection behavior for C-block piezoelectric actuator architectures

Although piezoelectric actuators are widely used in smart structure applications, they frequently can not generate directly both the force and deflection required. A new class of piezoelectric actuators, called C-blocks, have been developed that provide greater force than traditional bimorphs and greater deflection than stacks. C-blocks are piezoelectric bimorphs configured into a half circle shape and are fabricated on the mesoscale (10 - 10-3) mm). This paper describes how C-blocks can be used alone or combined in parallel and/or series, like building blocks, to form C-block actuator architectures to further improve force and/or deflection capabilities. This paper presents the derivation and experimental testing of force-deflection models for four common C-block architectures. These models predict the full static performance of C-blocks including the maximum performance characteristics. To test the models, force-deflection experiments were performed with a polymeric piezoelectric C- block. The experimental results are in close agreement with the behavior predicted by the model and demonstrate that a C-block has potential to generate approximately five times more force than an equivalent traditional straight bimorph and orders of magnitude greater deflection than an equivalent stack.