# A Review on Vibration Control Using Piezoelectric Shunt Circuits
## 1 Introduction  
Vibration suppression is a critical aspect in various engineering applications, aimed at improving performance, reducing noise, and extending the lifespan of structures and machines. The design of effective vibration absorbers plays a critical role in ensuring the optimal performance and longevity of equipment, regardless of whether the systems involved are on the microscale, such as MEMS, or larger-scale industrial applications. Poorly designed vibration absorbers can lead to a range of undesirable consequences, from increased noise pollution to poor performance and, eventually, system failure. Before a detailed discussion of the piezoelectric shunts is presented, the reader is referred to relatively new vibration suppression techniques. In the past two decades, the inerter has garnered much attention owing to its unique mechanical characteristics. As a substitution of the capacitance element based on the electrical-mechanical analogy, the inerter has outstanding advantages [1]. Inerter is a new element in the vibration isolation system. It can improve the vibration suppression ability of the system effectively. In addition,inerter is lightweight and has two free terminals compared with mass. These advantages make the application fields of inerter wider than those of mass. Vibration monitoring through smart controllers and a specific class of shell dampers. In particular, the reader can refer to the use of a smart controller for the assessment of drill string bottom-part vibrations and shock loads, [PERSON] et al. [2]. They used Smart 4 controller, which is equipped with a three-axis accelerometer and a gyroscope, paired with a lithium thionyl chloride battery. [PERSON] et al. [3] presented friction dampers based on the effects of dry friction because of their simple design, low manufacturing and maintenance costs, and high efficiency under heavy loads. This study proposed a new damper design based on an open shell with a deformable filler, with the shell cut along a cylindrical helical line. [PERSON] and [PERSON] [4] presented a new dry friction shell shock absorber design. The shock absorber contains two spring sections and a friction module with an open shell and an elastic filler; at the same time, the spring sections and the friction module work in parallel. The proposed device demonstrates good damping characteristics, is capable of operating under high operating loads, and at the same time has compact transverse dimensions. With a nonmonotonic loading of such a shock absorber, due to the contact interaction of the filler with an open shell, part of the energy that is supplied to the system will be dissipated. Piezoelectric shunt circuit absorbers have been used as a passive vibration absorber as an alternative to the traditional tuned mass dampers (TMDs), where they have the advantage due to their ease of tuning, straightforward implementation, and minimal added weight, making them a preferred choice for many applications [5,6]. Piezoelectric materials, known for their ability to convert mechanical energy into electrical energy and vice versa, have been extensively utilized for this purpose. Piezoelectric shunt circuits offer an effective method by dissipating vibrational energy through conversion into electrical energy, which is then dissipated in the circuit. Piezoelectric shunt circuits operate on the principle of the direct piezoelectric effect, where mechanical vibration induces an electrical charge in the piezoelectric material. This electrical energy is then routed into a shunt circuit, where it is dissipated, typically as heat, thereby reducing the mechanical vibration. The effectiveness of the shunt circuit depends on its ability to match the impedance of the piezoelectric transducer and the host structure, ensuring efficient energy transfer. Modeling involves understanding the electromechanical coupling, often using finite element methods, and tuning the circuit parameters to achieve desired damping.