Artificial muscle actuators comprising electrodes with an insulation bilayer

An artificial muscle actuator comprising:

• a housing comprising an electrode region adjacent an expandable fluid region;
• a dielectric fluid housed within the housing;
• and
• an electrode pair positioned in the electrode region of the housing, wherein:
• the electrode pair comprises a first electrode and a second electrode;
• the first electrode and the second electrode each comprise a metal film and an insulation bilayer disposed on the metal film, the metal film of the first electrode includes a first surface and an opposite second surface, the first surface facing the second electrode;
• the insulation bilayer of the first electrode is disposed on first surface and the second surface of the metal film of the first electrode;
• the insulation bilayer of the second electrode is disposed on the metal film of the second electrode in an orientation facing the first electrode;
• the insulation bilayer comprises an acryl-based polymer layer disposed on the metal film and a biaxially oriented polypropylene (BOPP) layer disposed on the acryl-based polymer layer;
• and
• the electrode pair is drawn together in response to an applied voltage, pushing the dielectric fluid into the expandable fluid region to hydraulically inflate the expandable fluid region.

A method of actuating an artificial muscle actuator, the method comprising:

• generating voltage using a voltage source electrically coupled to an electrode pair of the artificial muscle actuator, the artificial muscle actuator further comprising a housing having an electrode region and an expandable fluid region;
• wherein:
• a dielectric fluid is housed within the housing;
• the electrode pair is positioned in the electrode region of the housing;
• the first electrode and the second electrode each comprise a metal film, the metal film of the first electrode includes a first surface and an opposite second surface, the first surface facing the second electrode;
• the first electrode comprises an insulation bilayer disposed on the first surface and the second surface of the metal film of the first electrode;
• and
• the insulation bilayer comprises an acryl-based polymer layer disposed on the metal film and a biaxially oriented polypropylene (BOPP) disposed on the acryl-based polymer layer;
• and
• applying voltage generated by the voltage source to the electrode pair, thereby electrostatically drawing the first electrode and the second electrode together, pushing the dielectric fluid into the expandable fluid region to hydraulically inflate the expandable fluid region.