Researchers from the Universities of California, North Carolina, and Virginia have created a flexible aquatic robot inspired by the marine invertebrate known as feathered starfish. This robot can move in three dimensions in water and is powered by just two motors. The research paper was published in the journal Science Advances.
He adds: "By coordinating their multiple flexible arms, these creatures can swim in different directions, change position, and glide through the water, and we were particularly interested in this combination of flexibility and multimodal mobility."
Hot Topics
"But our goal wasn't to accurately mimic the feather starfish," explains Haitao. "We wanted to understand its basic locomotion strategy and how its multiple flexible limbs could work together as a single, coordinated body. This inspired us to wonder if we could build a robot whose own structure helps coordinate movement, allowing it to achieve complex three-dimensional swimming with minimal control input."
Haitao says that what distinguishes this new robot from other aquatic robots is its ability to achieve multi-pattern three-dimensional maneuvering using only two motors.
He explains: “Using the same robot structure, we can generate three completely different swimming patterns: a jellyfish-like pattern for ascending, descending, and hovering; a fish-like pattern for swimming forwards and backwards; and a spinner-like pattern for turning and changing direction. By combining these patterns, the robot can maneuver in three-dimensional space.”
What makes this possible is what researchers call "mechanical intelligence." Instead of dedicating a separate motor to each movement, they use flexible structure, structural interconnectivity, and interaction with the surrounding water to transform simple inputs into coordinated movements. In other words, some of the coordination and control is built into the robot's body itself.
According to the study, this is crucial because complex aquatic robots often gain greater maneuverability by adding more motors, mechanisms, and control channels.
The researcher adds: "But our work takes a different approach, which is to achieve more functionality through smarter mechanical design rather than simply adding more physical components."
The robot achieved a maximum swimming speed of about 1.64 times its body length per second, and a maximum rotation speed of about 90 degrees per second, while maintaining this simple operating structure.
Tags:
science