Robot cockroach 'can squeeze with ease through rubble to find disaster victims'

A scuttling robot cockroach has been developed that mimics the insect's creepy ability to squeeze through the narrowest gaps.

Just like a real 'roach, the palm-sized mechanised bug can keep crawling even when its body is squished to a fraction of its normal width.

The aim is not to shock those with a phobia of the six-legged disease-spreading pests.

Scientists believe cockroach technology could help in the search and rescue of victims buried under rubble as a result of storms, earthquakes or explosions.

Dr Kaushik Jayaram, from Harvard University, who led the US team, said: "What's impressive about ... cockroaches is that they can run as fast through a quarter-inch gap as a half-inch gap, by reorienting their legs completely out to the side.

"They're about half an inch tall when they run freely, but can squish their bodies to one-tenth of an inch - the height of two stacked pennies."

Cockroaches squeezing through crevices can also withstand forces the equivalent of 900 times their body weight without injury, he pointed out.

Inspired by the insects, Dr Jayaram designed a simple robot that can splay its legs outward when squashed and capped it with a plastic shield similar to the tough shell covering a cockroach's back.

The device, called Cram (compressible robot with articulated mechanisms), was able to run through cracks only half its height.

Colleague Professor Robert Full, the University of California at Berkeley, said: "In the event of an earthquake, first responders need to know if an area of rubble is stable and safe, but the challenge is, most robots can't get into rubble.

"But if there are lots of cracks and vents and conduits, you can imagine just throwing a swarm of these robots in to locate survivors and safe entry points for first responders."

He added: "This is only a prototype, but it shows the feasibility of a new direction using what we think are the most effective models for soft robots, that is, animals with exoskeletons.

"Insects are the most successful animals on earth. Because they intrude nearly everywhere, we should look to them for inspiration as to how to make a robot that can do the same."