Contoured fluid-filled chamber

An article of footwear having an upper and a sole structure that includes a fluid-filled chamber, the chamber comprising:

• a polymer material that defines a first surface, a second surface located opposite the first surface, and a sidewall surface extending around a periphery of the chamber and between the first surface and the second surface;
• and
• a plurality of separate bonds spaced inward from the sidewall surface and joining the first surface and the second surface, the bonds being distributed to form a hexagonal array, and the bonds being located at a midpoint between the first surface and the second surface,
• wherein the first surface and the second surface define elliptically-shaped structures between the bonds, the elliptically-shaped structures having a first eccentricity in a forefoot region of the chamber and a second eccentricity in a heel region of the chamber, the first eccentricity being less than the second eccentricity.

An article of footwear having an upper and a sole structure that includes a fluid-filled chamber, the chamber comprising a polymer material that defines

• a first surface oriented to face the upper, an elevation of the first surface in a heel region of the footwear being above an elevation of the first surface in a forefoot region of the footwear;
• a second surface located opposite the first surface, an elevation of the second surface in the heel region of the footwear being above an elevation of the second surface in the forefoot region of the footwear;
• and
• a plurality of bonds that join the first surface and the second surface, the bonds being distributed to form a regularly-spaced hexagonal array.

An article of footwear having an upper and a sole structure that includes a fluid-filled chamber, the chamber comprising:

• a polymer material that defines a first surface, a second surface located below the first surface, and a sidewall surface extending around a periphery of the chamber and between the first surface and the second surface;
• a plurality of bonds spaced inward from the sidewall surface and joining the first surface and the second surface, the bonds being distributed to form a hexagonal array;
• and
• a fluid located within the chamber,
• wherein the first surface has a first point that is centered between two of the bonds that are adjacent to each other, and the first surface has a second point that is centered between three of the bonds that are adjacent to each other, the first point being closer to the adjacent bonds than the second point, and the chamber having:
• an unpressurized state wherein the fluid has a pressure substantially equal to an ambient pressure surrounding the chamber, the first point being at a greater elevation than the second point when the chamber is in the unpressurized configuration;
• and
• an pressurized state wherein the fluid has a pressure greater than the ambient pressure, the first point being at an elevation of the second point when the chamber is in the pressurized configuration.