Design of flextensional transducers using homogenization design method

Abstract

Flextensional transducers consist of a piezoceramic (or a stack of piezoceramics) connected to a flexible mechanical structure that converts and amplifies the output displacement of the piezoceramic. Among the applications, they can be used as actuators and sonars. The transducer performance in these application depends on the distribution of mass, stiffness, and flexibility in the coupling structure domain, which is related to the coupling structure topology. By designing other types of coupling structures connected to the piezoceramic, we can obtain new types of flextensional transducers with enhanced performance for a desired application. In this work, we extended the method for designing flextensional transducers in static and low-frequency applications to dynamic applications by introducing the inertia effect in the optimization problem. The method applies topology optimization technique based on the homogenization design method, which consists of finding the optimal material distribution in a perforated design domain with infinite microscale voids. The problem is posed as the design of a flexible structure coupled to the piezoceramic that produces high output displacements in a specified point of the domain and direction, in a specified frequency. Therefore, it consists of designing a flexible structure with a specified mode shape in a desired resonance frequency. As a result, designs of flextensional transducers are presented.