Robotic Insects See Improvement

Flying insect-like robots that would be able to navigate situations too dangers for humans—such as environmental hazards and forest fires—are one step closer to becoming a reality.

Researchers at the School of Engineering and Applied Sciences recently completed the construction of an essential mechanism that allows the microbot to automatically adjust imbalances of the wings caused by natural impediments like wind.

“I am quite excited,” said Pratheev S. Sreetharan, lead author of the study and a graduate student at SEAS. “We are the only lab in the world that can build an upscale robotic insect.”

The mechanism, which weighs around 10 milligrams and is roughly the size of Abraham Lincoln’s face on a penny, obviates the use of a computer microchip.

By allowing the microbot to flap its wings asymmetrically in the event of turbulence, the central device is analogous to a car differential, which splits the torque so that the wheels can move at different speeds when the car makes a turn.

The research team parted from traditional approaches to the field of Flapping Wing Micro-Air Vehicles—which extensively uses electrical sensors and computer chips—by replacing electronic controls with “highly sophisticated” mechanics that adjust the wing speed and amplitude.

Microrobots have very little power and mass available for electronic sensors and chips, according to Sreetharan.

The microbotic research is part of the RoboBees Project, a larger initiative funded by the National Science Foundation that seeks to artificially mimic the behaviors of a bee colony and deftly adapt to changing environments.

“We’ve been using insights from biology as shortcuts to engineering,” said Associate Engineering Professor and study co-author Robert J. Wood in a 2007 interview, when he first announced the start of the project. “Hovering is the most attractive feature for application...Surveillance, for example, requires the machine to hover and stare.”

“This is a pretty ambitious project,” Sreetharan said.

—Staff writer Gautam S. Kumar can be reached at gkumar @college.harvard.edu.

—Staff writer Sirui Li can be reached at sli@college.harvard.edu.