Robo-roach controlled by people scuttles into reality
Experts hope the cockroach will gather information from places humans can't get to very easily
They lurk in dark corners, feed off crumbs - and obey the commands of their human overlords.
Years in the making, and a contender for the most revolting creation to emerge from a laboratory, the robo-roach has arrived.
Built by engineers in Texas, the robotic insect is a live cockroach with a miniature computer that is fused to the animal's nervous system. At the push of a button, a human operator can control the beast. Or, at least, which way it scuttles.
Hong Liang, who led the research at Texas A&M University, said the controllable insect could carry tiny video cameras, microphones and other sensors. With those on board, it could gather information from places where humans would rather not be - collapsed buildings, broken sewers, and the kitchens in student house shares.
"Insects can do things a robot cannot. They can go into small places, sense the environment, and if there's movement, from a predator say, they can escape much better than a system designed by a human," Liang said. "We wanted to find ways to work with them."
The US team made tiny backpacks for the cockroaches which contained a computer chip to send signals down a pair of fine wires into nerves that controlled legs on either side of the cockroach. With a rechargeable lithium battery to power the device, the total weight of the backpack was less than three grams.
In a series of demonstrations, the scientists showed how they remotely controlled the direction in which the cockroach walked by stimulating nerves on either side of its body. When cockroaches walk, the three legs on each side move in time with each other. But the electrical pulses disrupt this, making the middle leg fall out of step with the others. The result is that a pulse to the left makes the cockroach turn left.
The system is far from perfect. In tests when robotic roaches were held on little leashes, the insects could be steered about 70 per cent of the time. But when the insects were left to roam free, the remote control worked only 60 per cent of the time. To make them turn could take multiple jabs of the button.
Working with cockroaches has changed how Liang views the insects. "When I first saw them, my hair stood up. But I went on to keep some in my office as pets for a while. They are actually beautiful creatures. They are constantly cleaning themselves," she said.
How useful robotic roaches prove to be will depend in part on how much gadgetry they can carry.
Liang says some cockroaches can carry five times their own bodyweight, but the heavier the load, the greater the toll it takes on their performance. "We did an endurance test and they do get tired," Liang said. "We put them on a treadmill for a minute and then let them rest. If the backpack is lighter, they can go on for longer."
The team are now investigating how to make cockroaches respond to directions more reliably. Another avenue of inquiry is whether stimulating several legs at once can make the roach stop, start, walk and run on command. Roy Ritzmann, who studies how insects move at Ohio's Case Western Reserve University Ohio, said if cockroaches could be controlled for long periods, they could prove useful. "There are certainly cockroaches that are large enough and strong enough to carry reasonable payloads for providing intelligence," he said.
Sethu Vijayakumar, of the University of Edinburgh, has reservations. "As much as the technology is interesting, there are a lot of ethical issues before we go down that line, even with cockroaches," he said.
