Ferrofluidic Drops Controlled by Light: A New Frontier in Soft Robotics

In this study, Max Planck Institute for Intelligent Systems, the Chinese University of Hong Kong, and the Gwangju Institute of Science and Technology laid out the protocol of taking control of Ferrofluidic drops moving in water with light. Their paper published in Science Advances, show that new ideas in applying the soft robot technology are possible. Ferrofluidic

Academic studies have indicated that with the use of magnets, ferrofluid droplets, which are basically magnetic particles that are dispersed in oil, can be manipulated in water. For these reasons, cells have been known to use light to propel themselves in a particular direction, a feat that this new study expands upon.

The most interesting and famous property of ferrofluid droplets is its buoyancy when that is heated. The investigators of this study suspended these droplets in a water tank and used light to heat them. This made the droplets become lighter to buoyancy leading to rising of the droplets to the surface. To demonstrate the fluid’s ability to maneuver, the team followed a similar process, where they used a laser to control the droplets as they moved through a maze.

These controllable droplets are termed droplet robots or a kind of soft robots by the researchers. When surrounded by a hydrogen layer they resemble jellyfish like robots, controlled by sunlight or laser beams.

These robots are then envisaged to be utilized within the human body as drug delivery structures communicated with by an optical fiber light source. The future work will also involve the expansion of the use of this promising technology

References:

• • Researchers use light to control ferrofluid droplet movements in water

  • Individual and collective manipulation of multifunctional bimodal droplets in three dimensions