| abstract |
A fluid-filled structure, such as a bladder, is disclosed. The bladder has a first surface and an opposite second surface that are peripherally joined to define various edges. The bladder encloses a fluid between the first surface and the second surface. A portion of the edges may have a concave configuration, or the edges may have both concave and convex configurations. A shape of the bladder may be a tessellation pattern so that a plurality of the bladder may be efficiently. |