Starfish-inspired robot created: biomimetic structure is flexible and self-repairing

The starfish skeleton has inspired a new flexible yet resilient morphing structure with promising applications in roboticsaviation and medical technology.

This research is being presented at the Society for Experimental Biology Annual Conference in Prague, Tech Explore reports.

“Starfish have the remarkable ability to effortlessly maintain any body posture by varying the stiffness of their endoskeleton,” says Raman Raman, a PhD student in the Biological Structures and Biomimicry working group at the Hochschule Bremen in Germany.

Ossicles are microstructures of calcite found inside the body of starfish and are networked by collagen fibers to form the endoskeleton. This strong but simple structure allows them to adopt a wide variety of body postures with minimal use of energy.

“We were fascinated by this biological solution to a complex engineering problem,” Raman continues. “Our goal was to unlock the secrets of its intricate skeleton and translate those principles into a new material with equally remarkable properties.”

Raman and his team used a multidisciplinary approach for this project. Using high-resolution X-ray CT scans, they visualized the skeletal structures of sea stars and used mathematical models (finite element analysis and multibody simulations) to understand the complex, interrelated mechanics of the skeletal components.

“For the first time, we can show the complex three-dimensional structure of the starfish skeleton and the fine ultrastructure of the tiny bones,” Raman says. “We have now used this knowledge for the biomimetic design process of our own morphing structure, incorporating rapid prototyping techniques for its fabrication.”

Raman and his team have used 3D printing to produce a variety of functional prototypes that can overcome an impressive array of physical challenges. “Our patented starfish-inspired structure exhibits self-locking, continuous bending, self-healing, and shape memory characteristics,” Raman says.

The scalability, low cost, and relative ease of fabrication of this transformable structure provide many opportunities for industrial applications, including robotics, aviation, and biomedical devices such as prosthetics and implants.