Patent ID: 7748507

Claim:
A mechanical device, comprising: an elongate structural element, configured to absorb at least partially impacts by deformation, wherein the structural element comprises a profile of a selected straight section, the profile including localized alterations that are shaped and that are positioned on said selected straight section such that, when the selected straight section of the structural element is subjected to a combined force of compression in a longitudinal axis of the structural element and torque having an axis perpendicular to a plane passing through the longitudinal axis, the selected straight section undergoes two sequential phases of deformation, wherein the two sequential phases of deformation include a first phase of energy absorption by bunching of the selected straight section followed by a second phase of bending of the selected straight section, wherein the localized alterations are shaped and are positioned on the selected straight section such that the bending of the second phase occurs at the same place on the selected straight section of the structural element as the bunching of the first phase, wherein at least some of the alterations are asymmetrical with respect to opposing portions of said structural element along the longitudinal axis, and wherein said alterations comprise deformations formed in said structural element prior to the selected straight section undergoing said two sequential phases of deformation.