The future of robotics may be defined by an unlikely source: the tails of seahorses.
A new study cites the fish appendages as possible inspiration for a breakthrough after finding that its movements facilitate bending and twisting while also providing strong resistance to crushing—key components for engineers developing new technologies.
Researchers from Clemson University in collaboration with U.C. San Diego, Ghent University, and Oregon State University began their work by seeking to ascertain why seahorses’ tails are made up of square, as opposed to cylindrical (as found in most animals from rodents to monkeys), segments.
“Almost all animal tails have circular or oval cross-sections—but not the seahorse’s. We wondered why,” explained Michael Porter, assistant professor in mechanical engineering at Clemson University. “We found that the squared-shaped tails are better when both grasping and armor functions are needed.”
To arrive at their findings, the team created a 3D-printed version of a seahorse’s tail based on its square prisms and another model consisting of cylindrical segments. “New technologies, like 3D-printing, allow us to build idealized models of natural systems to better understand their different functions,” Porter said. “This study demonstrates that engineering designs are convenient means to answer elusive biological questions when biological data are nonexistent or difficult to obtain.”
The prototypes were twisted, bent, and hit with a rubber mallet to analyze the range of their functionality, with the square version proving to be stiffer and more resilient than its circular counterpart. With a far diminished ability to twist, this restriction could provide vital protection to the animal by preventing damage and enabling better control when latching onto things—crucial given their tendency to wrap their tails around stationary objects. It could also prove to be life saving when battling water birds—the sea creatures’ biggest predator—as they attempt to crush their prey with their beaks.
“Understanding the role of mechanics in these prototypes may help engineers to develop future seahorse-inspired technologies that mimic the prehensile and armored functions of the natural appendage for a variety of applications in robotics, defense systems, or biomedicine,” the researchers write. Porter believes that the seahorse tail could not only inspire new types of armor, but could also pave the way for robots with an ability to move, snake-like, on the ground, while contracting to fit into small spaces.
This isn’t the first time creatures from the animal kingdom have served as a muse for the world of robotics: a starfish-inspired mechanism developed by scientists at Harvard is being pegged as a future lifesaver in disaster zones. The “soft robot”—made from silicone rubbers—could be the next generation of these autonomous machines, proving simpler and cheaper to make than their metallic predecessors.
With an ability to withstand being run over by a car, direct exposure to flames and a snowstorm, and featuring a lightweight camera (which can transmit audio and video), the robot illustrates how mimicking the movements and dexterity of wildlife can lead to enhancements in the field.
Porter and his team are continuing to investigate how mechanisms loosely based on the structure of the seahorse’s tail might be applied to everyday life. One of the possibilities they have been considering is increasing the scale of the structure to create a large, robotic arm with the capacity to grip items, perhaps in hostile environments where it would be able to withstand the forces of crushing and twisting. With the potential of 3D printing growing exponentially over the past few years, combining this with inspiration from the animal world could prove to be revolutionary.