Electroactive polymer (EAPs)-based technologies have shown promise in areas such as artificial muscles, aerospace, medical devices and soft robotics because of large electromechanical actuation at relatively high speed. The promises of EAPs have led us to study EAP-based grippers. The in-plane actuation of P(VDF-TrFE-CTFE) is converted into bending actuation using unimorph configurations, where one passive substrate layer is attached to the active polymer. On-demand segmented folding is harnessed from this pure bending actuation by creating notch samples with an aim to implement them for applications like soft robotics gripper. In this paper, we studied the effect of various design parameters of notched folding actuators to establish a design reference and maximize the actuation performance of EAP based devices. Both finite element analysis (FEA) and micromechanics based analytical study is performed to investigate the effect of actuator parameters on the folding actuation of notched samples. The notched configuration has been analyzed via FEA for the non-uniform deformations and stress-fields. FEA analysis shows the importance of notch positioning to maximize the electromechanical performance. On the other hand, analytical study has proposed a design curve for the selection of proper notch parameters (e.g. notch length and Young’s Modulus) to maximize the actuation performance. Finally, based on the FEA and analytical analysis, a human finger inspired ‘finger-like’ biomimetic actuator is realized by assigning multiple notches to the structure.

Date Published: 29 March 2019
PDF: 15 pages
Proc. SPIE 10968, Behavior and Mechanics of Multifunctional Materials XIII, 109680P (29 March 2019); doi: 10.1117/12.2514902

Published in SPIE Proceedings Vol. 10968:
Behavior and Mechanics of Multifunctional Materials XIII
Hani E. Naguib, Editor(s)