Bug-size robots that fly and flip could pollinate futuristic farms’ crops

In the new design, each of the four units has a single flapping wing pointing away from the robot’s center, stabilizing the wings and boosting their lift forces. The researchers also improved the way the wings are connected to the actuators, or artificial muscles, that flap them. In previous designs, when the actuators’ movements reached the extremely high frequencies needed for flight, the devices often started buckling. That reduced the power and efficiency of the robot. Thanks in part to a new, longer wing hinge, the actuators now experience less mechanical strain and can apply more force, so the bots can fly faster, longer, and in more precise paths.

COURTESY OF THE RESEARCHERS

Weighing less than a paper clip, the new robotic insect can hover for more than 1,000 seconds—almost 17 minutes—without any degradation of flight precision.

“When my student Yi-Hsuan Hsiao was performing that flight, he said it was the slowest 1,000 seconds he had spent in his entire life. The experiment was extremely nerve-racking,” Chen says.

The new robot also reached an average speed of 35 centimeters per second, the fastest flight researchers have reported, and was able to perform body rolls and double flips. It can even precisely track a trajectory that spells M-I-T.

“At the end of the day, 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,” Chen says.

COURTESY OF THE RESEARCHERS

From here, he and his students want to see how far they can push this new design, with the goal of achieving flight for longer than 10,000 seconds.

They also want to improve the precision of the robots so they could land in and take off from the center of a flower. In the long run, the researchers hope to install tiny batteries and sensors so the robots could fly and navigate outside the lab. The design has more room for those electronics now that they’ve halved the number of wings.

The bots still can’t achieve the fine-tuned behavior of a real bee, Chen acknowledges. Still, he says, “with the improved lifespan and precision of this robot, we are getting closer to some very exciting applications, like assisted pollination.”