Interdigitated cellular cushioning
An interdigitated cellular cushioning system includes an array of void cells protruding from each of two binding layers interdigitated between the two binding layers. Peaks of each of the void cells are attached to the opposite binding layer forming the interdigitated cellular cushioning system. The interdigitated cellular cushioning system may be used to absorb and distribute a source of kinetic energy incident on the interdigitated cellular cushioning system (e.g., an impact or explosion) so that the amount of force transmitted through the interdigitated cellular cushioning system is low enough that it does not cause injury to personnel or damage to personnel and/or equipment adjacent the interdigitated cellular cushioning system.
1. An interdigitated cellular cushioning system comprising:
a first sheet of thermoplastic elastomer material defining a first binding layer having a top surface and a bottom surface, each of the top surface and the bottom surface being either planar or curved, and a first array of void cells contiguous with and protruding from the first binding layer, each void cell in the first array extending from the top surface and having a base integral with the binding layer, a wall, and a peak; and
a second sheet of thermoplastic elastomer material defining a second binding layer having a top surface and a bottom surface, each of the top surface and the bottom surface being either planar or curved, and a second array of void cells contiguous with and protruding from the second binding layer, each void cell in the second array extending from the top surface and having a base integral with the second binding layer, a wall, and a peak,
wherein the walls of the void cells in the first array are distinct from and non-contactingly spaced from the walls of the void cells in the second array, and wherein the peaks of the void cells in the first array are welded to the top surface of the second binding layer at first attachment points and the peaks of the void cells in the second array are welded to the top surface of the first binding layer at second attachment points, and
wherein the void cells in the first array and the void cells in the second array are configured to collapse under a load and return to an uncollapsed state when the load is removed.
2. The interdigitated cellular cushioning system of claim 1 , wherein the void cells in the first array and the void cells in the second array have a hollow interior volume.
3. The interdigitated cellular cushioning system of claim 1 , wherein the void cells in the first array and the void cells in the second array have one or more of a hemiellipsoidal, cubic, hemispherical, conical, truncated conical, and pyramidal shape.
4. The interdigitated cellular cushioning system of claim 1 , wherein the first attachment points surrounding a base of a void cell in the second array are equidistant, and the second attachment points surrounding a base of a void cell in the first array are equidistant.
5. The interdigitated cellular cushioning system of claim 1 , wherein at least one of the first binding layer and the second binding layer is configured to conform to a curved surface.
6. The interdigitated cellular cushioning system of claim 1 , wherein the void cells in the first array and the void cells in the second array do not rely on air pressure to provide resistance to deflection.
7. The interdigitated cellular cushioning system of claim 1 configured to be installed within a helmet.
8. The interdigitated cellular cushioning system of claim 1 , wherein the void cells in the first array and the void cells in the second array are configured to monotonically collapse under a load.
9. An interdigitated cellular cushioning system comprising:
a first planar thermoplastic elastomer binding layer;
a second planar thermoplastic elastomer binding layer;
a first array of truncated conical void cells, the void cells in the first array having a peak, a wall, and a base, the base of the void cells connected to the first binding layer and the peak of the void cells in the first array welded to the second binding layer at a first planar attachment point, with each base creating a discontinuity in the first binding layer; and
a second array of truncated conical void cells, the void cells in the second array having a peak, a wall, and a base, the base of the void cells connected to the second binding layer and the peak of the void cells in the second array welded to the first binding layer at a second planar attachment point, with each base creating a discontinuity in the second binding layer, wherein the walls of the void cells in the first array are distinct from and non-contactingly spaced from the walls of the void cells in the second array,
wherein the void cells in the first array and the void cells in the second array are configured to collapse under a load without fracturing.
10. The interdigitated cellular cushioning system of claim 9 , wherein the void cells in the first array and the void cells in the second array have a hollow interior volume.
11. The interdigitated cellular cushioning system of claim 9 , wherein the first attachment points surrounding a base of a void cell in the second array are equidistant, and the second attachment points surrounding a base of a void cell in the first array are equidistant.
12. The interdigitated cellular cushioning system of claim 9 , wherein at least one of the first binding layer and the second binding layer is configured to conform to a curved surface.
13. The interdigitated cellular cushioning system of claim 9 configured to be installed within a helmet.
14. The interdigitated cellular cushioning system of claim 9 , wherein the void cells in the first array and the void cells in the second array are configured to monotonically collapse under a load.
15. A method of manufacturing an interdigitated cellular cushioning system comprising:
molding a first sheet of thermoplastic elastomer material into a first binding layer with a first array of void cells protruding from the first binding layer, each void cell having a base integral with the first binding layer and a peak;
molding a second sheet of thermoplastic elastomer material separate from the first sheet into a second binding layer with a second array of void cells protruding from the second binding layer, each void cell having a base integral with the second binding layer and a peak;
interleaving the first array of void cells with the second array of void cells so that the peaks of the first array of void cells are proximate the second binding layer and the peaks of the second array of void cells are proximate the first binding layer and so that the void cells of the first array do not contact the void cells of the second array;
attaching the peaks of the void cells in the first array to a planar attachment point on the second binding layer; and
attaching the peaks of the void cells in the second array to a planar attachment point on the first binding layer.
16. The method of manufacturing the interdigitated cellular cushioning system of claim 15 , wherein the interdigitated cellular cushioning system is configured to be installed within a helmet.
17. The method of manufacturing the interdigitated cellular cushioning system of claim 15 , wherein the void cells in the first array and the void cells in the second array are configured to monotonically collapse under a load.