Variable stiffening device comprising electrode stacks in a flexible envelope

A variable stiffening device comprising:

• a flexible envelope comprising a plurality of fluid chambers each fluidically separate from one another by one or more divider portions;
• a dielectric fluid housed within the plurality of fluid chambers;
• and
• a plurality of electrode stacks each comprising a plurality of electrodes and a plurality of abrasive strips;
• wherein:
• the plurality of electrodes comprise one or more positive electrodes and one or more negative electrodes stacked in an alternating arrangement;
• each electrode stack is housed within and is configured to receive voltage;
• and
• an individual abrasive strip is positioned between each pair of adjacent electrodes of each of the plurality of electrode stacks such that such that when voltage is applied to the plurality of electrode stacks thereby drawing adjacent electrodes together, the plurality of abrasive strips generate frictional engagement between adjacent electrodes thereby actuating the variable stiffening device from a relaxed state to a rigid state.

A method of actuating a variable stiffening device, the method comprising:

• generating voltage using a voltage source electrically coupled to an electrode stack of the variable stiffening device, the variable stiffening device further comprising a flexible envelope that comprises a fluid chamber;
• wherein:
• the electrode stack comprises a plurality of electrodes and one or more abrasive strips positioned between at least one pair of adjacent electrodes of the plurality of electrodes;
• and
• the electrode stack is housed within the fluid chamber together with a dielectric fluid;
• and
• applying voltage generated by the voltage source to the electrode stack, thereby electrostatically drawing adjacent electrodes together, such that the one or more abrasive strips generate frictional engagement between adjacent electrodes and actuate the variable stiffening device from a relaxed state to a rigid state.