An Hoo controller design scheme based on the matrix fraction stability condition is proposed for the vibration control of a flexible manipulator, which has the matrix fraction uncertainty. The proposed controller is then applied to the cantilever beam with a piezoelectric-type servo-damper so that the vibration at the free end of the beam is effectively suppressed, while its effective length sl...

This paper discusses the selection process for piezoelectric transducers (PZT) used as actuator elements for suppressing vibrations in a flexible beam system. The effects of changing physical parameters such as the relative thickness of the piezoelectric ceramic with respect to the beam, the optimum location of the PZT actuator, and the length of the PZT are studied based on the singular value ...

This paper presents a piezoelectric energy harvester using an eccentric cylinder undergoing bending–torsion vibration in low-speed water. It can harvest energy from water using vortex-induced vibration (VIV). A distributed parameter beam model with respect to the motion of the piezoelectric beam was established based on Euler–Bernoulli beam theory. The governing coupled equations of the harvest...

The built-in piezoelectric fields in group III-nitrides can act as road blocks on the way to maximizing the efficiency of opto-electronic devices. In order to overcome this limitation, a proper characterization of these fields is necessary. In this work nano-beam electron diffraction in scanning transmission electron microscopy mode has been used to simultaneously measure the strain state and t...

In this paper, a numerical solution procedure is presented for the free and forced vibration of a piezoelectric nanowire under thermo-electro-mechanical loads based on the nonlocal elasticity theory within the framework of Timoshenko beam theory. The influences of surface piezoelectricity, surface elasticity and residual surface stress are taken into consideration. Using Hamilton’s principle, t...

Piezoelectric transducer (PZT) patches can be attached to structures in order to reduce vibration. The PZT patches essentially convert vibrational mechanical energy to electrical energy. The electrical energy can be dissipated via an electrical impedance. This paper introduces a method of implementing an arbitrary impedance using a current source and digital signal processor (DSP). The \synthet...

We propose a spiral-shaped piezoelectric bimorph power harvester operating with coupled flexural and extensional vibration modes for applications to low frequency energy sources. A theoretical analysis is performed and the computational results show that the spiral structure has relatively low operating frequency compared to beam power harvesters of the same size. It is found that to optimize t...

This study presents a generic TITOP (Two-Input Two-Output Port) model of a substructure actuated with embedded piezoelectric materials as actuators (PEAs), previously modeled with the FE technique. This allows intuitive assembly of actuated flexible substructures in large flexible multi-body systems. The modeling technique is applied to an illustrative example of a flexible beam with bonded pie...

This paper describes an approach to harvest electrical energy from a mechanically excited piezoelectric element. The structure of piezoelectric energy harvester is optimized for maximum power with minimum dimensions through Genetic Algorithm approach to enhance the conversion of mechanical energy into electrical energy using direct piezoelectric effect. Numerical analysis is carried out to obta...

This study reports piezoelectric properties and crystallographic microstructures of aluminium nitride (AlN, wurtzite structure) thin films on 50 μm thick stainless steel foil. The transverse piezoelectric coefficient d31,f and e31,f of 10 μm thick AlN films were estimated as -1.42 ± 0.08 pm/V and -0.48 ± 0.03 C/m 2 from a tip displacement of the piezoelectric cantilevers. Dielectric constant ε3...