The key, he told them, is that the caterpillar's body is made of "smart material," a term familiar to engineers. Smart material has its function built in, so it doesn't take much brain power to make it do its thing, like a foam mattress that always returns to its original shape. Some smart materials change shape when a modest electric current is applied. The material, like the outer skin of a caterpillar, "knows" what it's supposed to do.
Thus robots, based on biological models, wouldn't need a complex control system, because the function would be encoded in the tissues of the robot. Like the caterpillar, a tiny "brain" could run the show.
The first synthetic caterpillar will look pretty much like an overgrown caterpillar, Trimmer says. But it should be easy to scale it down to a size so small it could work inside the human body, flexing its way through blood vessels, or even into the lungs, says Trimmer.
During its lifetime, a caterpillar increases its body mass 10,000 fold, Trimmer says.
"If we use the same principles to build our robots we'll be able to scale them up or down, make them small or very big quite easily," he adds.
And if he's right, here's the best part. These little critters will be dirt cheap, because once all the bugs are sorted out, it won't take much to produce them.
"You could make them disposable," Trimmer says. "You could compress a bunch of robots into a canister, and shoot them into a mine field. The canister breaks open, all these little critters crawl out and go off in different directions. When they find a mine, they send out a signal. You don't care if they get blown up because they don't cost $100,000 each. They cost 50 cents."
Maybe so, but it's hard to believe the Tufts team can come even close to matching the marvels of the caterpillar.
The caterpillar is one of the most successful animals on the planet. It's found on nearly every tree in the world, Trimmer says. And at the end of its life it turns into a moth.
"That's like a PC suddenly turning into a Macintosh," Trimmer says.
And the amazing thing is the caterpillar, and the moth it becomes, have the same set of genes. Somewhere along the way, the caterpillar rewires its own system.
"It keeps the same neurons," Trimmer says, "but they do a different job in the moth than they do in the caterpillar. That's remarkable because it must know what it's supposed to be in two different life stages. That never ceases to amaze me."
So it's quite possible that the Tufts team will learn some astonishing things from the caterpillar. But surpass it? Not likely.