Elizabeth Pennisi | Why is it so hard to squash a cockroach?

Elizabeth Pennisi, Science:

Insects, whether they creep or fly, live in a world of hard knocks. Who has not stepped on a cockroach, then raised her shoe to watch the creature get up and scoot under a door? Bees and wasps, for their part, face a never-ending obstacle course of leaves, stems, and petals—bumblebees crash their wings into obstacles as often as once a second. Now, researchers are learning how these creatures bend but don’t break.

The results do more than explain why cockroaches are so hard to kill. By mimicking the combination of rigid and flexible parts that gives insect exoskeletons and wings their resilience, biomechanicists are making robots tougher. “Bend but not break is a lot of what happens in these insects,” says Harvard University roboticist Robert Wood. “We’re trying the same thing to see if we can have similar robustness in our robots.”

Until recently, most engineers designed for a tough-and-tumble world by making machines stiff and sturdy or agile enough to avoid danger. Modern cars incorporate a third approach: They absorb impacts by crumpling, sacrificing the structure to protect the occupants. “Nature has come up with a tactic that we don’t have,” says David Hu, a mechanical engineer at Georgia Institute of Technology in Atlanta. “Crumple … and then keep on going.”


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