Tunable structural member for a vehicle generally comprises an active
material adapted to selectively undergo a change in at least one
attribute in response to an activation signal. The change in the at least
one attribute results in a change in the mechanical properties of the
tunable structural member. Active materials generally include shape
memory alloys, shape memory polymers, magnetorheological fluids and
elastomers, piezoelectrics, electroactive polymers, and the like.