A prototype shape-shifting robot is rather like a bacterium, with a tail that "folds away" when it enters the human bloodstream. The robot can carry drugs to specific areas all over the body through the bloodstream. It can also offer help during operations.
It has been created by scientists from the Ecole Polytechnique Federale Lausanne (EPFL) and the Eidgenössische Technische Hochschule Zürich (ETHZ).
"We show that both a bacterium's body and its flagellum play an important role in its movement," said EPFL scientist Selman Sakar, who teamed up with Hen-Wei Huang and Bradley Nelson at ETHZ. "Our new production method lets us test an array of shapes and combinations to obtain the best motion capability for a given task. Our research also provides valuable insight into how bacteria move inside the human body and adapt to changes in their microenvironment."
The micro-robots, or bio-inspired robots, are "soft, flexible and motor-less." They have been made with biocompatible hydrogel and magnetic nanoparticles that are responsible for giving the robots their shape. Secondly, they respond to electromagnetic fields, prompting them to swim and move.
The manufacturing process is complicated. The nanoparticles are packed within layers of a biocompatible hydrogel. After that, through an electromagnetic field to orientate the nanoparticles at different parts of the microbots, the team took a polymerization step in order to solidify the hydrogel. The robot is next put under water. It folds there in a number of ways depending on the nanoparticles' orientation within the gel. The 3D architecture of the microbot is thus formed.
Electromagnetic fields are used to make the robot swim. A laser beam can heat the robot and enable it to change shape.
Finally, the robot "mimics the behavior of the African trypanosomiasis, a parasitic bacterium that uses its flagellum (tail) for propulsion, but wraps it around itself when inside the host's body."
However, the exciting microbots are still in the initial stages. They need to be researched further before they can be finalised.
The paper has been published in the journal Nature Communications.
