Piezoelectric d₁₅shear response-based torsion actuation mechanism: an experimental benchmark and its 3D finite element simulation

Abstract

An experimental benchmark is proposed for piezoelectric, direct-torsion actuation using mono-morph piezoceramic d 15 shear patches. This is reached by designing and assembling an adaptive plate having two identical composite faces sandwiching a core made of connected six oppositely polarized (OP) piezoceramic d 15 shear patches along the length. An electronic speckle pattern interferometry system was used to measure the static tip deflection of the adaptive sandwich composite plate that was mounted in a cantilever configuration and actuated in torsion by progressively applied voltages on the piezoceramic shear core electroded major surfaces. Then, the effective rate of twist was post-processed and proposed as an evaluation criterion for smart composites under piezoelectric torsion actuation. For verification of the experimental results, the proposed experimental benchmark was simulated using three-dimensional piezoelectric finite elements (FE) within ABAQUS ® commercial software. The comparison of the obtained experimental and simulation results showed reasonable agreement, but the slight nonlinear experimental response was not confirmed by the linear FE analysis. The experimentally proved torsion actuation mechanism, produced by OP piezoceramic d 15 shear patches, can be applied actively to prevent torsion in many applications, such as in wind turbines, helicopter blades, robot arms, flexible space structures, etc.

Static experimentations of the piezoceramic d15-shear actuation mechanism for sandwich structures with opposite or same poled patches-assembled core and composite faces

“…These curves indicate that the d 15 -shear actuated composite benchmarks responses are nonlinear, in terms of the applied voltages, starting from 107 V for the OP-50mm, 91.5 V for the SP-50mm and 92.5 V for the SP-75mm benchmarks, respectively. This experimental nonlinearity was already shown in the open literature for the extension (d 31 effect) actuation mechanism (EAM) [4][5][6][7] and for the torsion actuation mechanism (TAM) [11], while it is shown here for the first time for the present shear actuation mechanism (SAM).…”

“…Static strain and deflection are generally measured using light probes, as in [5], or strain gages, as in [6]. However use of the so-called electronic speckle pattern interferometry (ESPI) is becoming very popular for both conventional [8] and smart [9][10][11] structures. This is due in particular to the fact that the ESPI system provides more sensitive and full-range measurement possibilities than strain gages and has the advantage of being able to measure deformations and deflections of engineering structures and materials without contact.…”

Enhanced torsional actuation and stress coupling in Mn-modified 0.93(Na0.5Bi0.5TiO3)-0.07BaTiO3 lead-free piezoceramic system

“…Butz et al [10] conducted a numerical analysis on a bimorph torsional transducer composed of two adjacent piezoceramic rods (PZT-5H) bonded to each other along their width with polarization axes opposite to each other in the same plane. In that study, a bimorph d 15 torsion transducer was theoretically introduced [10] which was later experimentally demonstrated by Berik and Benjeddou [11] using a sandwich patch actuator made of axially oppositely poled (OP) two adjacent rows of triple PZT PIC 255 patches and glass fiber reinforced polymer (GFRP) face covering layers. The torsion actuation mechanism (TAM) [11,12] has been further analyzed [13] by conducting quasi-static and static experiments for a benchmark that was validated through Saint Venant-type solutions presented by Krommer et al [14,15].…”

Piezoelectricd15shear-response-based torsion actuation mechanism: An exact 3D Saint-Venant type solution

“…A benchmark was recently proposed consisting of a slender cantilever beam comprising two piezoceramic layers with opposite polarization along their length and perfectly bonded along their width by Butz et al [21]. This concept was experimentally proven by Berik and Benjeddou [22] for a cantilever plate consisting of two identical glass fiber/epoxy faces sandwiching a core torsion actuator; the latter mimics the benchmark by using a total of six segmented d 15 piezoceramic patches. Yet, a thorough mathematical analysis of this electromechanically coupled problem has not been reported; the latter is the topic of the present paper.…”