MIT’s Latest Bug Robot Is a Super Flyer. It Could One Day Help Bees Pollinate Crops.

Rapid declines in insect populations are leading to concerns that the pollination of important crops could soon come under threat. Tiny flying robots designed by MIT researchers could one day provide a mechanical solution.

Numbers of critical pollinators like bees and butterflies are declining rapidly in the face of environmental degradation and climate change, which research suggests could put as much as one third of the food we eat at risk.

While the most obvious solution to this crisis is to find ways to reverse these declines, engineers have also been investigating whether technology could help plug the gaps. Several groups have been building insect-scale flying robots that they hope could one day be used to pollinate crops.

Now, a team at MIT has unveiled a new design that they say is much more agile than predecessors and capable of flying 100 times longer. The bug-sized bot is powered by flapping wings and can even carry out complex acrobatic maneuvers like double aerial flips.

“The amount of flight we demonstrated in this paper is probably longer than the entire amount of flight our field has been able to accumulate with these robotic insects,” associate professor Kevin Chen, who led the project, said in a press release. “With the improved lifespan and precision of this robot, we are getting closer to some very exciting applications, like assisted pollination.”

The new design, reported in Science Robotics, weighs just 750 milligrams (0.03 ounces) and features four modules, each consisting of a carbon-fiber airframe, an artificial muscle that can be electrically activated, a wing, and a transmission to transfer power from the muscle to the wing.

Previous versions of these modules featured roughly the same configuration, but with two flapping wings apiece. However, Chen says this resulted in the downdraft of the wings interfering with each other, reducing the amount of lift generated. In the new set-up, each module’s wing faces away from the robot, which boosts the amount of thrust it can generate.

One of the main reasons for the short shelf life of previous designs was the significant mechanical stress generated by the flapping movement of the wings. An upgraded transmission and a longer wing hinge helped to reduce the strain—allowing the robot to generate more power than before and last longer.

Put together this allowed the robot to achieved average speeds of 35 centimeters per second (13.8 inches per second)—the fastest flight researchers have reported—and sustained hovering for nearly 17 minutes. “We’ve shown flight that is 100 times longer than anyone else in the field has been able to do, so this is an extremely exciting result,” says Chen.

The robot was also able to carry out precise maneuvers, including tracing out the letters MIT in midair, as well as acrobatic double flips with a greater rotational speed than a fruit fly and four times as fast as the previous quickest robot.

Currently, the bug-bot is powered by a cable, which means it can’t move about freely. But the researchers say cutting down the number of wings freed up space on the airframe that could be used to install batteries, sensors, and other electronics that would enable it to navigate outside the lab.

That’s likely still some way off though. For now, Chen says the goal is to boost the flight time by another order of magnitude and increase the flight precision so the robot can take off and land from the center of a flower.

If all that comes together, however, our beleaguered natural pollinators may soon have some much-needed help in their efforts to keep our food systems ticking.