Cars have dent resistant side panels, crumple zones and composite bumpers to absorb and disperse impact energy protecting occupants. Each of these improvements share a common feature: once activated or deformed, their load carrying capacity is diminished. A bistable structure is such that, once activated, it has a second stronger phase which has the ability to sustain higher loads. This allows for a better distribution of damage, and in addition the structure keeps its integrity for a longer time. Initial tests have verified this concept proving that a bistable structure under tensile loading has the capacity of absorbing more energy than a similar monolithic structure under the same load conditions. Bistable structure behavior has also been shown for a system composed of advanced fiber reinforced composites, which has the potential of being a break-through for applications where energy absorption is sought.
