Imagine a future where tiny robotic bees, no bigger than a penny, buzz around fields of wildflowers, assisting their natural counterparts in essential pollination tasks. This vision, which has been a long-term goal of Harvard’s Microrobotics Laboratory, is now a step closer to reality. Until recently, the primary challenge faced by the Harvard RoboBee was its inability to land gracefully. Now, researchers have equipped it with four long, flexible legs inspired by the legs of crane flies—those harmless, spindly insects often mistaken for giant mosquitoes. This innovation, detailed in a study published Wednesday in the journal *Science Robotics*, brings the RoboBee one step closer to practical applications that might have seemed like science fiction just a few years ago, such as environmental monitoring, disaster surveillance, artificial pollination, and even the manipulation of delicate organisms. Previously, if the RoboBee needed to land, researchers would simply turn off the robot a short distance above the ground and hope it landed upright and safely. “This often resulted in a crash landing, which was not ideal,” said Christian Chan, a PhD student at Harvard University’s School of Engineering and Applied Sciences and a co-author of the study. To overcome this challenge, the team, led by Robert Wood, a professor of engineering and applied sciences at Harvard, sought inspiration from nature. They delved into the university’s Museum of Comparative Zoology database and ultimately decided to model the RoboBee's landing legs after those of the crane fly. The chosen design features four long, jointed legs, which allow the robot to make a gentle, controlled descent. In addition, the team updated the RoboBee’s controller, the equivalent of its brain, to better manage the landing process and decelerate the robot’s approach. The problem the researchers were addressing is known as the "ground effect." This phenomenon occurs when the air vortices generated by the RoboBee’s flapping wings create instability close to the ground, leading to uncontrolled landings. Similar issues affect helicopters, but they are particularly challenging for the RoboBee, which weighs just 0.004 ounces (1/10th of a gram) and has a wingspan of only 1.2 inches (3 centimeters). “The successful landing of any flying vehicle depends on minimizing velocity as it approaches the surface and dissipating energy quickly upon impact,” explained Nak-seung Patrick Hyun, a former Harvard postdoctoral fellow and now an assistant professor at Purdue University’s School of Electrical and Computer Engineering. Hyun, who led the landing tests, noted that the ground effect can be significant for a robot with tiny wing flaps, and the aftermath—bouncing and tumbling—can be even more problematic. The new crane fly-inspired legs and the updated controller work together to ensure a gentle and stable touchdown. This is not just a matter of graceful landings; the improved design also protects the RoboBee’s delicate piezoelectric actuators, which are the robot’s equivalent of muscles. “Piezoelectric actuators are fragile and lack fracture toughness,” the researchers noted in the study. “The compliant legs help to absorb impact and prevent these actuators from breaking during crash landings.” Future developments for the RoboBee include integrating sensor, power, and control autonomy. According to the team, achieving this "three-pronged holy grail" will be crucial for making the robot’s practical applications viable. With these advancements, the RoboBee could soon become a valuable tool in various fields, from ecological research to disaster response. The team’s tests, which included landings on both solid surfaces and leaves, have shown promising results. This breakthrough not only enhances the RoboBee’s operational capabilities but also underscores the potential of biomimicry in solving complex engineering challenges. As the tiny robot continues to evolve, it brings us closer to a future where technology and nature work hand in hand to address some of the world’s pressing environmental issues.