Electroactive polymer-based actuators for artificial muscles and soft robotics

Summary:

Ionic electroactive polymer based artificial muscles are promising alternative to traditional actuators, especially where compliant muscle-like response is desirable. The short cycle life and robustness of the fabrication technique are two important issues limiting applications of soft conducting polymer based actuators. Short life-time is often a consequence of delamination of the components due to stresses at the interface during the actuation. We develop a fabrication technique for conducting polymer based actuators that could be up-scalable and enable facile integration of sensory feedback.

To favor a strong adhesion to PEDOT: PSS electrodes, wetting properties of a PVDF membrane surface were improved using Ar plasma-induced surface polymerization of PEGMA.

PEDOT:PSS/PVDF/PEDOT:PSS actuators were then made by simple drop-casting or ink-jet printing. Actuators with high strains of 0.6% were obtained and showed no signs of delamination after more than 150 hours or 104 actuation cycles. Recently, we have shown that sprayed carbon nanotube carpets can significantly reduce electrochemical creeping by facilitating charge and discharge of the conducting polymer and, consequently leads to a more reversible harmonic cycling.

Illustration of a fabrication process flow for a solvent casted actuators

Merged images of the actuator at its extremities during actuation applying square wave with frequency of 50 mHz and 2.0 V amplitude. Actuator displacement profile vs time of a function of the applied voltages.

 

Contact:

C. Bergaud

 

Collaborations:

B. Tondu and P. Souères, Gepetto Team, LAAS ; E. Flahaut, CIRIMAT, Toulouse

 

Financial Support:

PhD Grant from DGA (French Ministry of Defense)

 

Selective list of publications:

  • A. Simaite, F. Mesnilgrente, B. Tondu, P. Souères, C. Bergaud “Towards inkjet printable conducting polymer artificial muscles”, Sensors and Actuators B, 229, 425-433 (2016)
  • A. Simaite, B. Tondu, P. Souères, C. Bergaud « Hybrid PVDF/PVDF-graft-PEGMA Membranes for Improved Interface Strength and Lifetime of PEDOT:PSS/PVDF/Ionic Liquid Actuators”, ACS Applied Materials & Interfaces, 7 (36), 19966-19977 (2015)