Patent ID: 8065903

Claim:
An energy absorber comprising: at least one layer of energy absorbing material, each layer having a plurality of cells within the respective layer of energy absorbing material, wherein each layer of energy absorbing material deforms when a force applied to the at least one layer of energy absorbing material reaches a threshold force level; a fluid filling the plurality of cells in each respective layer of energy absorbing material; and a skin covering external surfaces of each respective layer of energy absorbing material to contain the fluid within the cells of the respective layer of energy absorbing material, wherein the skin is configured to break open, allowing the fluid to be expelled, when the force applied to the energy absorbing material causes the respective layer to deform; wherein the threshold force level for each layer of energy absorbing material is based on a viscosity of the fluid in the cells of the respective layer and on a crush strength of the respective layer of energy absorbing material.