Active Actuating of a Simply Supported Beam with the Flexoelectric Effect

Abstract

Piezoelectric materials with the electro-mechanical coupling effect have been widely utilized in sensors, dampers, actuators, and so on. Engineering structures with piezoelectric actuators and sensors have provided great improvement in terms of vibration and noise reduction. The flexoelectric effect—which describes the coupling effect between the polarization gradient and strain, and between the strain gradient and electric polarization in solids—has a fourth-rank order tensor electro-mechanical coupling coefficient, and in principle makes the flexoelectricity existing in all insulating materials and promises an even wider application potential in vibration and noise control. In the presented work, a flexoelectric actuator was designed to actuate a simply supported beam. The electric field gradient was generated by an atomic force microscopy probe. Flexoelectric control force and moment components could be induced within the flexoelectric control layer. As flexoelectricity is size-dependent, the key parameters that could affect the actuating effect were examined in case studies. Analytical results showed that the induced flexoelectric control moment was strongly concentrated at the probe location. The controllable transverse displacement of the simply supported beam was calculated with the modal expansion method. It was found that the controllable transverse displacement was dependent on the probe location as well.

Soft Functionally Gradient Materials and Structures – Natural and Manmade: A Review

“…[188] Besides conductivity, EGM with gradient dielectric permittivity to enhance converse flexoelectric effect under electric potential has also been proposed for sensing, actuation, etc. [189][190][191] A ceramic-polymer permittivity gradient composite was prepared by sequential deposition of increasing ceramic particles in a PDMS substrate (Figure 7b). [192] The resulting permittivity gradient was used to generate an electric field gradient, and hence, a larger deformation was induced by the electric field gradient-induced stress.…”

Vibrating Flexoelectric Micro-Beams as Angular Rate Sensors

“…Recently, there has been a growing interest in the flexoelectric effect [14][15][16][17], with which, flexural motion in a homogeneous beam [18][19][20] or plate [21] can be excited or detected with only electrodes. In particular, flexoelectric beams have already been used as actuators or sensors in electromechanical devices [22,23]. This offers the possibility of flexoelectric angular rate sensors.…”

Ultrahigh flexoelectric effect of 3D interconnected porous polymers: modelling and verification

“…The flexoelectricity has demonstrated its broad application prospects in areas of sensing 16,17 , mechanical actuating 18,19 , energy harvesting 20 and high-density data storage 21 .…”