Underwater structures that can dynamically change their shape, similar to fish, are more efficient in movement than conventional rigid ones. However, creating deformable devices that can change the shape of their bodies has been a challenging and time-consuming process. The RoboTuna developed at MIT, for example, consisted of about 3,000 different parts and took approximately two years to create.

MIT researchers and their colleagues have now proposed an innovative approach to creating deformable underwater robots using simple repeating substructures instead of unique components. This new modular system, published in the journal Soft Robotics, allows for virtually unlimited variations in shape and scale, making it a game-changer for robot jobs in underwater environments.

The new system, developed by Parra Rubio and his team, can be easily expanded to larger sizes without requiring the kind of restructuring and redesign necessary for existing systems. The low density and high rigidity of the lattice elements called voxels that make up their system provide ample opportunities for further expansion.

The team demonstrated the new system in two different configurations: one resembling a snake and the other a wing. The snake-like structure, consisting of 60 parts, was assembled in about two days, showcasing the efficiency of the modular system. The structure was tested in MIT's experimental pool and proved capable of generating sufficient thrust to move forward with wave-like movements.

The wing-like device, also made of the same voxels, can change the shape of its profile, controlling the lift-to-thrust ratio and other properties. This concept can be applied to various purposes, such as generating energy from waves and increasing the efficiency of ship hulls. The wing is covered with an array of tiles that maintain waterproof tightness even when the curvature of the wing changes.

The concept can also be applied to other vessels, such as racing yachts, where a keel or rudder that can bend smoothly during a turn can provide an additional advantage. According to the researchers, this will help "pass the turn much more efficiently."

The innovative modular system for deformable underwater robots offers a scalable, efficient, and versatile design for various robot jobs. By simplifying the creation process and allowing for virtually unlimited shape and scale variations, this approach has the potential to revolutionize the field of soft robotics and underwater exploration.