Video Robofly To study the aerodynamics of flapping flight... Credit: Michael Dickinson, California Institute of Technology  View Video Requires Real Player

Evolution has produced a wide range of intelligent, mobile sensor units in the form of living organisms ranging from insects to humans. Compared to current robots, insects and other animals often have much more flexible and efficient control of their movements. Some researchers study organisms to develop better robots, while others build robots to better understand the organisms.

A research team at the University of Illinois led by Fred Delcomyn is one group that has developed a six-legged robot modeled after cockroaches, in this case the American cockroach Periplaneta americana. The researchers hope to mimic the insect's extraordinary speed and agility by learning and applying the biological structure and principles in the robot's design.

Hexapod robot, MARK I, developed at the University of Illinois... Credit: © F. Delcomyn, University of Illinois, 1996

Insect flight, particularly the airborne maneuvers of the fruit fly Drosophila melanogaster, has been the decade-long research pursuit of Michael Dickinson at Caltech. Dickinson has tethered flies to poles and mimicked them with robots to examine the mechanics of their muscles and the flight control behind the rapid rotation of their wings.

Researchers study not only whole organisms but also their parts for possible use in robotic applications. Take hair, for example. Chang Liu at the University of Illinois has developed microscopic sensors modeled on biological hair cells for a robotic imitation of the "lateral line" fish use to sense vibrations in the water. Other researchers have looked to mimic hair-like cilia, which help some single-celled organisms swim, in motors for microscale robots.

UC Berkeley engineering professors Robert Full and Ron Fearing have studied how the feet of geckos allow the lizards to stick to almost any surface. This work has translated both into gecko-inspired robots with sticky feet and treads (built by iRobot) and to an NSF nanoscience award to develop synthetic gecko adhesives and a biology award to understand animal movement.

Humanoid robots can also help to better understand humans. For example, to learn how people routinely make complex movements, researchers from the University of Southern California and Carnegie Mellon University have built robots that can copy humans to learn skills, including tennis forehands and arm gestures, and improve these skills through practice. And Jessy Grizzle at the University of Michigan has taught a robot to walk on two feet to get a deeper understanding of the control mechanisms involved in walking. Such understanding could lead to improved physical therapy for stroke and spinal cord injury patients and to better prosthetics.