Design of Piezoelectric Actuators By Optimizing the Electrodes Topology

Abstract

Piezoelectric materials based actuators are highly recognized for the development of microrobotic systems thanks to their high bandwidth, high resolution and high force density. However, one of their main drawback is the low relative stroke (0.1% of actuator's size) that limits the actuator motion range. Overcoming this limitation is challenging but would increase the achievable working space of microrobots. In this paper, topology optimization method is used to maximize the actuator stroke. Instead of optimizing only the material density, we also consider the optimization of the electrodes polarity. This approach allows to combine both material expansion and compression in order to increase the actuator output displacement. To demonstrate this approach, two actuators were designed starting from a full domain considered as a basic reference piezoelectric actuator. The first design considered only the density optimization while the second one took into account the optimization of the topology of electrodes. Both simulation and experiment showed a good agreement between the obtained designs and the fabricated prototypes. The result revealed that the optimized design with polarization has an improved factors of 2.8 and 2.02 compared to full plate and actuator without electrodes optimization, respectively.

Reliability-based topology optimization of piezoelectric smart structures with voltage uncertainty

“…( 6), which may generate numerical singularity in the finite element analysis. To avoid this problem and ensure the accuracy of displacement response, normalization method is adopted as the author's previous work in (Homayouni-Amlashi et al 2020). The normalization mechanical stiffness matrix and the normalization piezoelectric coupling matrix are expressed as follows…”

“…In this study, we propose an RBTO method of piezoelectric smart structures with multi-parameters optimization based on the author's previous work (Homayouni-Amlashi et al, 2021). The proposed approach embeds reliability analysis into the entire topology optimization process, providing a proper design that meets reliability requirements.…”

“…Wang et al (2014) employed the level set function to describe the geometrical shapes and placement of the piezoelectric actuators for optimizing the positions of the movable actuators and the topology of the host structure based on independent point-wise density interpolation (iPDI) approach. Schlinquer et al (2021) designed a piezoelectric actuator by topology optimization combining both piezoelectric material expansion and compression when the voltage condition imposed to each plane-stress element was the same and performed experiments to validate the obtained designs. However, while the working strokes of piezoelectric smart structures have been extended successfully through the introduction of topology optimization, so far the uncertainty of the overall structures has been completely neglected.…”

Comparing Different Electrodes of Piezoelectric Single Crystal Composites for Underwater Acoustic Transducers

“…Pb-based relaxor piezoelectric single crystal composites (PSCCs) show great potential for improving the performance of next generation underwater acoustic transducers (UATs) owing to their superior electromechanical and piezoelectric properties compared to piezoelectric ceramic composites and their higher figure of merit ( d 33 × g 33 ) compared to piezoelectric single crystals (PSCs). − The electrode plays a significant role for piezoelectric materials in directly determining the reliability and electrical efficiency of piezoelectric devices. To maximize the advantages of piezoelectric materials in devices, a major part of research on piezoelectric material electrodes is focused on structural design to meet flexibility requirements or achieve a high piezoelectric response of devices. − In addition to high efficiency and good flexibility, the adhesion durability of electrodes in maintaining the electro performances of PSCCs during the service period is also essential.…”

Piezoelectric MEMS Linear Motor for Nanopositioning Applications

“…The combination of two orthogonal bending modes in a 10 × 10 mm 2 Mn-BSPT square plate recently demonstrated linear speeds of 200 mm/s with payloads above 35 g [13]. However, attaining high linear speeds and high payloads, together with accurate and precise positioning is a challenge of recent interest in piezoelectrically actuated microrobots [14]. Tellers et al [15] proposed a linear conveyor based on an array of PZT-actuated microhammers, capable of transporting 2 mg masses at 1 mm/s with 5 V excitation and positional errors as low as 80 µm, without speed control.…”