WASHINGTON -- Scientists have created a small robotic device that guides itself safely through a beating pig's heart, demonstrating what such tools might one day do in surgery.

And they borrowed some tricks from animals to do the job. To find its way to a specific point in the heart, the thin tube called a catheter gently tapped its path along heart walls and to a valve, much like how cockroaches skitter along walls and rats reach out with their whiskers

Researchers from Boston Children's Hospital tested their robot in pigs. Experienced doctors were a little faster threading catheters into place. But researchers say robotic devices might one day do routine steps in operations so doctors could focus on more complicated tasks.

The research was published Wednesday in Science Robotics.