Endoscopy generally isn't much fun. It's easier in the rare cases when a patient can swallow a tiny camera, instead of having a long cord threaded down the throat or through the intestines.
But such "capsule endoscopy" has limited value to many doctors: The capsules travel one way, twist to face the wrong direction and can't be steered to trouble spots, experts said.
So University of Colorado engineer Kamran Mohseni has added tiny engines to the mini-cameras. His goal is to let doctors guide the tiny machines to a damaged area in a person's intestines, where they could deliver medicine, take pictures or collect a biopsy.
"The basic idea comes from squid locomotion," Mohseni said.
Mohseni and his colleagues think their innovative "squid engines," submitted for a patent, also could be used to make extremely maneuverable underwater vehicles, useful in search-and-rescue missions or exploration.
Squid "jump" to catch prey by quickly forcing water out of a cavity, Mohseni said: "The jet of water rolls out in a vortex ring, and the vortex ring goes one way, the squid goes the other."
He's used that concept to create "vortex thrusters," engines that use the power of a swirl to move. The engines, which punch air or water out an opening, can work in fluid or air, although they're designed slightly differently for each, Mohseni said.
Because air fills the small intestine after a night's fast, he uses puffs of air to delicately maneuver his prototype capsule.
That prototype is penny-sized -- too big for most of the small intestine, Mohseni said. But it was a cheap first draft, and he's optimistic that with better materials and a few more months, he and his students can produce something far smaller.