Tufts University and Virginia Tech collaborated on an interesting study that has implications in robot locomotion ( Gut Movements in Caterpillars Have Impact on Robotic Design):

BLACKSBURG, Va., July 23, 2010 – Weird movements in the abdomens of freely crawling caterpillars are making headlines in the fields of engineering and biology, says Jake Socha, Virginia Tech assistant professor of engineering science and mechanics.

Beyond evolutionary implications, the findings are already contributing to the design and development of soft material robots.

…combined imaging showed that the caterpillar’s gut slid forward in advance of the surrounding tissues. Seem inconsequential? Actually, it is “unlike any form of legged locomotion previously reported and represents a new feature in our emerging understanding of crawling,” they reported in Current Biology.

The novelty is that the caterpillar’s center of mass moves forward while the middle ‘legs’ are anchored to the substrate. The internal gut movements are locally decoupled from visible translations of the body.

“This type of two-body mechanical system has never been seen before, and is probably unique to soft, squishy animals,” Socha explained.

Read the entire article and see video at: http://www.physorg.com/news199007129.html