While robots like Boston Dynamics’ Spot or the manipulator arms that assemble automobiles can achieve some pretty impressive feats, they’re still quite limited by their fixed form. Some applications may require a slightly more flexible robot. A recently published article in Scientific robotics describes a new type of robot that aims to meet these needs.
Using “shape morphing” material, the researchers designed a robot that can be transformed from a flat shape into a variety of complex shapes. Although the robots built for the study serve more as a proof of concept than an industry-ready product, the design marks a breakthrough in the field of soft robotics by demonstrating a material that is flexible enough to change shape but tough enough to support different functions. .
The material consists of metal tubes embedded in rubber sheets. These sheets are structured in patterns inspired by the Japanese art of kirigami, a variant of origami in which the paper is both cut and folded. (In recent years, the structural advantages and malleability offered by kirigami-based designs have inspired numerous engineering research teams.)
Initially a flat mesh sheet, the material can be made into complex shapes depending on the situation. When a new shape is needed, the mesh is folded into a new structure. To restore it to its original shape, small heating elements in the mesh melt the metal – a special type of metal called a low melting point alloy – while the rubber tube springs back to its original shape. The metal then resolidifies.
This process can occur in as little as a tenth of a second and can be repeated multiple times without failure. Above all, if something breaks, it can be repaired by heating and reshaping the composite. Taken together, the material has what its creators call “reversible plasticity.” This allows for some pretty remarkable things, like the robot transforming from a ground vehicle into a small flying drone and then back again, harmless.
The researchers also used the material to create a craft capable of floating on the surface of water and then submerging like a submarine. other modifications allow the craft to collect objects with its hull before returning to its form.
The actual applications of a shape-shifting robot like this have yet to be seen. The researchers suggest the materials could be used to create machines that can self-repair, interface with humans in new ways, or even be worn. One promising aspect of the designs is that they are strong enough, at least at this scale, to withstand the forces of engines and propulsion systems.
Still, it’s not the first soft robot to be built. But the material used here is new and represents a different approach to existing models. These models, which are designed for tasks as diverse as exploring the oceans or help improve mobility, are also in the early stages of development. Beyond their abilities to shape change or endure conditions that more traditional robots would struggle with, robots made from soft materials would be safer for people to work with in many situations and could enable the automation in situations where it is currently impractical or unsafe.