Dr. Robot, master of surgery

Imagine a tiny snake robot crawling through your body, helping a surgeon identify diseases and perform operations.

It's not science fiction. Scientists and doctors are using the creeping metallic tools to perform surgery on hearts, prostate cancer, and other diseased organs. The snakebots carry tiny cameras, scissors and forceps, and even more advanced sensors are in the works. For now, they're powered by tethers that humans control. But experts say the day is coming when some robots will roam the body on their own.

But Dr. Argenziano and experts in robotics say the new creations work best when they're designed for very specific tasks. “The robot is a tool. It is no different in that sense than a scalpel. It's really a master-slave device,” he said. Howie Choset has been researching and building robots, particularly snake robots, at Pittsburgh's Carnegie Mellon University for years.

Mr. Choset believes that his snake robot and others like it help reduce medical costs by making complex surgeries faster and easier. Mr. Choset says his new design is smaller and more flexible than earlier models — the diameter of the head is less than the size of a dime.

The size of surgical robots allows surgeons to operate with far less damage to the body, helping the patient heal faster. For example, instead of opening the entire chest up during heart surgery, a small incision is made, and the robot crawls inside to the proper spot.

Dr. Ashutosh Tewari of Cornell University Medical Centre has used robotic tools to perform thousands of prostate operations. He said the precision of the tiny robotic tool is vital not just to cutting out cancerous tumours, but to seeing exactly what nerves to leave intact.

Dr. Tewari said he's most excited about the potential for surgical robots to do things humans can't do. He said the variety of sensors available for surgical robots keeps expanding, even as they get smaller.

Mr. Choset has also built larger snake robots designed for search and rescue, or just exploration. They can climb poles or trees and then look around through a camera in the head, and slither through places humans can't reach.

“We sent our snake robots into these caves off the coast of the Red Sea to look for evidence of ancient Egyptian ships,” he said.