Scientists create 3cm robot cockroach that can withstand the weight of a human

Scientists have created a new insect-sized robot that's virtually weightless, yet can still withstand the density of a human being. Researchers at the University of California, Berekely, developed the miniature device based on the durability of cockroaches. Measuring just one inch-long and 1.5cm wide, it's lighter than a grain of sand can scurry across the floor at a speed comparable with the real thing. Developers hope the gadgets can assist in future search and rescue missions, where they can access hard-to-reach places. The robot was built using Piezoelectric materials, which expands or contracts in response to electric voltage. To manage this reaction, researchers coated the PVDF in a layer of an elastic polymer, which made the material bend, rather than grow or shrink.