Patent ID: 8916262

Claim:
A structure comprising two or more composite components and at least one core component disposed directly between at least two of the composite components, each of said composite components having a negative effective Poisson's ratio, each composite component comprising: a first component and a second component, the first component and the second component extending longitudinally relative to an axis, the first component being provided around the second component through one or more turns, the one or more turns being spaced longitudinally relative to the axis, wherein variation in tensile or compressive load on the first component causing variation in radial position of the second component relative to the axis; wherein the first component has a higher modulus of elasticity than the second component; wherein the first component is arranged around the second component in a helical manner, wherein the variation in the tensile or comprehensive load on the first component causing variation in the diameter of the helix of the first component, the variation in the diameter of the helix of the first component causing the second component to form a helix and/or causing variation in the diameter of the helix of the second component, so that the diameter of the second component helix increases as the diameter of the first component helix decreases, and the diameter of the second component helix decreases as the diameter of the first component helix increases; wherein the diameter and/or cross-sectional area of the first component is less than that of the second component; wherein the first component of a first composite component is wrapped around the second component of the first composite component in one direction in the helical manner and the respective first component of a further composite component is wrapped around the respective second component of the further composite component in the helical manner in the opposite direction, wherein the first composite component is a mirror image of the further composite component.