Design, modeling and testing of d33-mode surface-bondable multilayer piezoelectric actuator

In this work, a surface-bondable multilayer piezoelectric actuator, which utilizes the '33' electromechanical coupling for actuation, has been designed, modeled and tested. This actuator was developed to excite thick and stiff structures. The most commonly used form of piezoelectric actuator-the piezoelectric patches-are typically used for actuating thin beams, plates and shells. On the other hand, for actuating large, thick and stiff structures, piezoelectric stack actuators are preferred, due to their ability to generate larger block forces. But, unlike the piezoelectric patches, which are just bonded to the surface of the substructure with epoxy adhesive, the implementation of the stack actuators present certain drawbacks. Traditionally, the stack actuators have to be either integrated into the structure, or be utilized like an electrodyanmic exciter. Both of these methodologies of actuation are accompanied by several complications-large weight penalty being one of them-which render the choice of stack actuators undesirable for several applications. To overcome these shortcomings, and to offer a feasible solution, the concept of the surface-bondable multilayer piezoelectric actuator is proposed in this article. Besides retaining the actuation capabilities of a regular stack actuator, the design of the surface-bondable multilayer piezoelectric actuator allows it to be bonded to the surface of the substructure (like a piezoelectric patch). Thus, this design allows us to access the best of both worlds-the ease of implementation achieved with the patches, and the high actuation capability of the stack actuators. The design of the actuator, the inspiration for the design, the mechanism of operation of the actuator, its performance against other piezoelectric-based actuation methodologies, and the experimental validation of the concept, form the contents of the article.