Modeling of SoFT Electrohydraulic Polymer (SEH) Actuators*
*For a more in-depth explanation, see "A physics-based modeling of a hydraulically amplified electrostatic actuator" published in the Journal of Physics.
Project Objective
Use COMSOL Multiphysics to examine the complex physics of the actuator and provide an underlying principle for the electrohydraulic polymer actuator system.
Presenting the dynamic performance of the actuators, including the fluid dynamics, fluid properties, and the relationship between the fluid mechanics, solid mechanics, and the electrostatics physics.
Simulate:
The experimental testing conditions and provide predictive data on film deformation.
The fluid motion and general fluid dynamic properties
Provide preliminary data on the output force-displacement relationship.
This study describes an alternative to the current state of modeling HASEL actuators.
Methodology and Results
The current model is modeled in two space dimensions, the analysis is conducted along the cross-section along the x-y plane.
The physics and geometry can be mirrored about the x-axis.
To capture the motion of the actuator system, this model considers a time-dependent study.
Three fundamental physics modules are applied in this model.
The solid mechanics is applied to the film, wherein the film is classified an orthotropic material according to the commercial materials used in experimentation.
The electrostatics physics, the dielectric liquid and the film material are described as the regions of interest because the film and the liquid act as the deformable dielectric medium.
For the fluid dynamics physics, a laminar, incompressible flow using a Newtonian fluid is considered; the Navier-Stokes equation and the continuity equation describes the dynamics of the dielectric fluid within the film pouch.
The experimental conditions are simulated within the model.
The model results:
Provides the response time and the displacement in relation to the applied voltage for a single actuator unit.
Provides data on the motion of the fluid within the packet.
Provided data on the electric field, stress on the film material, and pressure on the fluid before, during, and after actuation.
