Variable stiffness apparatuses using an interconnected dual layer fluid-filled cell array

An apparatus comprising:

• a substrate having a first side and an opposing second side;
• and
• a plurality of structures coupled to the substrate, where each structure comprises:
• a flexible first portion having a first end, a second end, and a sidewall extending between the first end and the second end, the first portion defining a single first chamber;
• and
• a second portion having a first end, a second end, and a sidewall extending between the first end and the second end, the second portion defining a single second chamber;
• a medial portion extending between the first and second portions, the medial portion defining a single channel in fluid communication with the first chamber and the second chamber;
• where each of the plurality of structures is coupled to the substrate such that each of the first and second portions is disposed on the first side of the substrate, and
• where for each structure the first portion of the structure and the second portion of the structure are not in fluid communication with any other structures of the plurality of structures.

An apparatus comprising:

• a substrate having a first side, a second side, and an aperture extending between the first side and the second side;
• and
• a structure extending through the aperture of the substrate, the structure comprising:
• a flexible first portion having a first end, a second end, and a sidewall extending between the first end and the second end, the first portion defining a single first chamber;
• and
• a second portion having a first end, a second end, and a sidewall extending between the first end and the second end, the second portion defining a single second chamber in fluid communication with the first chamber;
• a medial portion extending between the first and second portions, the medial portion defining a single channel in fluid communication with the first chamber and the second chamber;
• where the medial portion is disposed in the aperture such that the first portion is disposed on the first side of the substrate, and the second portion is disposed on the second side of the substrate, where the first chamber and the second chamber include a liquid.