Image Courtesy: Raphael Zufferey
Researchers at the Massachusetts Institute of Technology have developed a bird-inspired robot capable of swimming underwater, taking off directly from the water’s surface, and flying through the air. The breakthrough marks the first time a bird-sized robot has successfully transitioned between both environments using the same set of wings.
The robot, described in a study published in the journal Science, was inspired by diving seabirds such as the Atlantic puffin, which uses its wings for both flight and underwater propulsion. Engineers spent two years designing the half-pound machine, which features a wingspan of just under three feet and relies on flapping wings instead of propellers.
Unlike real diving birds, the robot has no legs. Instead, researchers engineered its wings to generate enough thrust to launch it directly out of the water, a demanding maneuver that requires the wings to flap about ten times per second. During normal flight, the wings flap only five to six times per second. To reduce complexity and weight, the team also avoided foldable wings, choosing flexible wing structures reinforced with carbon fiber instead.
Image Courtesy: Raphael Zufferey
The robot’s open-frame design allows water to flow through its body, meaning every electronic component had to be individually waterproofed. This approach also makes the robot neutrally buoyant, allowing it to remain suspended underwater without sinking or floating.
Mechanical engineer Raphael Zufferey, who led the project, said studying the flight and diving behavior of puffins helped guide the robot’s design. Researchers also calculated optimal launch angles and wing dimensions to maximize efficiency. On a single battery charge, the robot can fly nearly four miles or swim for just over one mile.
Scientists say the technology could eventually be used to monitor coral reefs, harmful algal blooms, fish populations, coastal erosion, and even marine mammals. Glenna Clifton, an animal movement biologist at the University of Portland who was not involved in the research, described the robot as “a monumental step” for aerial-aquatic robotics, noting that bio-inspired machines not only benefit from biology but can also help scientists better understand how animals move.
