Piezoelectric coupling as a feature sensitive to structural alterations

The paper presents an exploratory study about the use of electro-mechanical coupling measurements as a feature for detecting structural alterations using piezoelectric transducers. This coupling between the piezoelectric transducers and the structure can be estimated by means of low frequency vibration measurements and will prove to be a feature sensitive to structure alterations and scarcely influenced by temperature variations. Moreover, the approach proposed is designed such that it can also employ piezoelectric elements already available in the system for other purposes (e.g., vibration control), thus not requiring any additional expensive device, and can work while the system to be monitored is operating. The paper introduces at first the principle of the method and shows how to improve its accuracy by connecting the piezoelectric transducers with proper electric impedances. Then, numerical simulations and experimental results are presented to prove the feasibility of the proposed approach

Comprehensive analysis of a butterfly-shaped piezoelectric shunting vibration absorber for robust vibration reduction and isolation: Theoretical and experimental validation

The Piezoelectric Shunting Vibration Absorber (PSVA) has garnered attention for its effectiveness in vibration control. This paper aims to propose a novel PSVA capable of simultaneously amplitude reduction and vibration isolation under various conditions. The PSVA consists of a butterfly-shaped link component and a piezoelectric stack, connected to the structure to be damped via bolts. Subsequently, an equivalent schematic diagram of the PSVA is established, and its equivalent stiffness is determined. Taking a single-degree-of-freedom structure as an example, considering the dynamic stiffness of the shunting circuit, a dynamic model of the electromechanical coupled system is developed, obtaining the system's acceleration response and force transmissibility frequency response functions. Following this, experimental equipment is designed and fabricated, and the performance of the PSVA is tested under various excitation conditions. Finally, inspired by the experimental results, a segmented inductance circuit is designed and tested for its capability to broaden the vibration control bandwidth