Compressible dielectric elastomer actuators in high hydrostatic pressures: Models and experiments.

Area of Science:

• Materials Science
• Robotics
• Polymer Science

Background:

• Dielectric elastomer actuators (DEAs) are promising soft actuators for extreme environments like deep-sea exploration due to their inherent compliance.
• However, their performance under high hydrostatic pressures is poorly understood, limiting their practical application.
• Existing theoretical models and experimental techniques are insufficient for characterizing DEAs under such conditions.

Purpose of the Study:

• To develop a coupled theoretical model for DEAs under hydrostatic pressure.
• To introduce novel experimental techniques for characterizing DEA behavior under high hydrostatic pressures.
• To investigate the effects of hydrostatic pressure on DEA mechanical and electromechanical properties.

Main Methods:

• Development of a hydrostatic pressure-coupled DEA model.
• Implementation of experimental characterization techniques for DEAs under hydrostatic pressure.
• Testing DEAs at pressures up to 105 MPa, simulating deep-sea conditions.

Main Results:

• Observed stiffening of the elastomer with increasing hydrostatic pressure.
• Quantified reduction in actuation strain under high hydrostatic compression.
• Reported an increase in the electrical breakdown field strength of DEAs at elevated pressures.
• Model predictions align with experimental observations.

Conclusions:

• Hydrostatic pressure significantly alters DEA properties, including mechanical stiffness, actuation strain, and electrical breakdown strength.
• The developed model and experimental methods provide accurate characterization of DEAs under high hydrostatic pressures.
• This research offers essential guidelines for designing robust DEAs for deep-sea applications and advanced soft robotic systems.