Inkjet printing of a low actuation voltage dielectric elastomer actuator

Inkjet printing of a low actuation voltage dielectric elastomer actuator

Elschot, Sanne (TU Delft Mechanical, Maritime and Materials Engineering)

Tichem, M. (mentor)
Hunt, A. (graduation committee)
Goosen, J.F.L. (graduation committee)

Delft University of Technology

Mechanical Engineering | Micro and Nano Engineering

2021-07-23

Dielectric elastomer actuators (DEAs) are a type of soft actuators that consist of a dielectric elastomer membrane, covered with an electrode on the top and the bottom. When applying a potential, the opposite charges on the electrodes induce an electrostatic force which squeezes the elastomer, causing it to expand. This expansion can be used as an actuation mechanism, in a wide variety of applications. A specific field of interest are low actuation voltage DEAs. These DEAs require low stiffness and thin elastomer layers, but are easier and cheaper to implement due to the lower voltage requirements. The goal of this research is to develop a manufacturing process for an inkjet-printed low actuation voltage DEA while achieving insights into the requirements and limitations of the steps involved with this process. By using the PiXDRO LP50 inkjet printer in combination with the Dimatix DMC printhead, the bottom electrode is printed on a Novele substrate with Mitsubishi NBSIJ-MU01 AgNP ink. A dielectric elastomer ink has been formulated consisting of polydimethylsiloxane (PDMS) and octyl acetate (OA) in 1:4 and 1:3 ratios. These inks have been characterised on several printability parameters, placing both formulations in the jettable range based on their Z-value. Although theoretically jettable, both formulations showed difficult jetting behaviour. To resume the research, the PDMS layer is instead applied by spin coating. The PDMS surface is hydrophobic, requiring surface treatment before the electrode can be printed on top. Several methods have been investigated, of which O2 plasma treatment showed the best results. The top electrode is printed using NovaCentrix Metalon JS-B25P AgNP ink. Several different sintering methods have been explored to cure the printed silver. Next to the experimental work, a finite element analysis model has been built to provide a basis for designing low actuation voltage DEAs.

Dielectric Elastomer Actuator
Inkjet printing
soft electronics
PDMS
manufacturing

http://resolver.tudelft.nl/uuid:718af51f-43ec-46b0-9a40-787a171f6768

Student theses

master thesis

© 2021 Sanne Elschot