Researchers at Eindhoven University of Technology in the Netherlands have developed artificial cilia that can surpass reality. Tiny projections often adorn the exterior of certain cells in nature, and this artificial version can help propel small biomedical robots or feed microfluidic bombs. Artificial cilia rely on magnetic fields to generate motion, and researchers have already shown that they can move soft little robots in a variety of ways, including the ability to “walk” on vertical surfaces and even upside down.
Soft robots have enormous biomedical potential. Their physical properties make them a good match for our fabrics and allow them to perform tasks that would be difficult or impossible for a rigid device. Scientists have been expanding what is possible in this field, and this latest development provides new capabilities for small robots.
The idea of small robots that can perform therapeutic functions within our body has existed for a long time, and new developments bring this concept from the realm of science fiction to reality. However, handling such small devices is a challenge that requires a bit of ingenuity. These researchers were inspired by hair-like projections called cilia, which certain cells use to move or move liquids near them. These projections beat like a whip and are very effective in producing coordinated waveform movements that resemble a traveling wave created by sports fans in a stadium.
To achieve this using artificial materials, the researchers incorporated carbonyl iron powder particles into a mixture of polymers and used it to create small cilia-like projections by pouring the polymer into a mold. As the polymer cured, the team placed magnets near the molds, resulting in a slightly different alignment of the particles and magnetic properties in each cilia.
Once they removed the structure of the mold, the researchers used rotating magnets to create a magnetic field around the resulting soft robot, and this stimulated the cilia to move in a travel wave due to the slightly different magnetic properties of the adjacent cilia.
If the cilia are placed at the bottom of the structure, they can push them along. The resulting movements are quite impressive, as the robot can climb vertical surfaces and even walk upside down on an inverted horizontal surface. Turning the magnets in the opposite direction causes the robot to reverse its direction. Aside from medical robots, technology can also be useful for propelling very small amounts of water through microfluidic systems.
Watch a video about the technology below:
Study a ACS Mater application. Interfaces: Μ-Metachronial cilia for integrated chip pumps and climbing robots