Rise Of The Biobots

In nature, elegant engineering solutions abound. The robotics world is working to unravel them.

- Michelle Z. Donahue

My escorts and I walked for five solid minutes through a converted World War II–era warehouse, winding through a maze of dim corridors and a cavernous rail bay, then through a lab full of spacecraft skeletons in the midst of prototyping. We finally reached the workbench where the Navy is building...a robot squirrel.

“Squirrel” is a bit of a stretch, as the first fully built-out version of the Meso-scale Robotic Locomotion Initiative (MeRLIn) will weigh 10 to 20 pounds when it’s finished this spring—a monster of a rodent, by anyone’s definition. The robot in its current form consists of a rectangular manifold and the 10th iteration of a dog-jointed leg, mounted on a sliding aluminum strut. A bright-blue 3-D printed model nearby showed how it will look when complete: a headless, four-legged machine about the size of a Yorkshire terrier.

But when the project’s engineers fired it up to give me a demonstration, I saw why they refer to MeRLIn as a squirrel: Despite its tiny motors and hydraulic-driven pistons, it can jump like hell.

MeRLIn is just one of the recent robots that have animals to thank for their inspiration. The animal kingdom is rife with examples of clever sensing and movement, and efficiency is king in the battery-driven, limited-power world of autonomous robotics. The ability to imitate a kangaroo’s jump, for instance, would realize an ideal tradeoff between power and performance: The tendons in their formidable hind limbs store energy between every stride, allowing the animals to travel long distances with relatively little energy expenditure.

Biology is behind some of the most innovative robotic designs emerging today: Look at UC Berkeley’s Salto, inspired by the high-jumping African bushbaby, or the University of Virginia’s mantabot, modeled after cownose rays of the Chesapeake Bay.