Berkeley Researchers Create Cockroach-Inspired Robots

The common cockroach is hard to kill, and scientists at Berkley have modeled new, small robots on the roach. The smaller robots are about the size of a cockroach and are nearly as hardy as the insect as well. The scientists say that if you try and crush this robot under your foot odds are it will simply keep going.

The scientists says that most robots built at this scale are very fragile, and if stepped on, they are destroyed. Mechanical engineering professor Liwei Lin says that the team has found that with its new robots if you put weight on them, "it still more or less functions." Small robots that are controllable and can carry sensors have potential use in a myriad of scenarios.

They could, for instance, be of help in a search and rescue missions to squeeze into places where dogs and humans can't. The bot could also be useful in environments where its too dangerous for a human to go. The team says in an earthquake its hard for machines and dogs to find life under debris, small robots such as these could be very useful in such situations.

The robots created by the team are about the size of a postage stamp and made of a thin sheet of a piezoelectric material called polyvinylidene fluoride or PVDF. A piezoelectric material is something that causes the materials to expand or contract when an electric voltage is applied. In the robots, the PVDF is coated with a layer of an elastic polymer that causes the sheet to bend rather than expanding or contracting.

A front leg is added so that as the material bends and straightens under the electrical field, the oscillations propel the robot forward in a leapfrog motion. The robots move at 20 body lengths per second, said to be the fastest speed of insect-scale robots. The bots weigh less than one-tenth of a gram and can withstand the weight of about 60 kg. The bot is currently tethered, but testing is underway for untethered bots.