Microrobots from Drexel University

Microrobotics is not only hot in Europe. "A team of researchers at Drexel has developed an assembly of microscopic robots, suspended in liquid, that assemble and swim together at remarkable speeds when exposed to a rotating magnetic field.  This finding represents a key step in the development of 'microswimmers' for the delivery of medicine and the performance of surgery inside the body.

The robot chains move as a long, screw-like propeller as each individual robot in the chain spins in response to the external rotating magnetic field. Increasing the external field strength increases the rate the robots spin at which, in turn, increases the velocity of the robot chain, allowing the velocity of the chain to be controlled. The magnetic field can also be used to divide the chain into shorter segments as, at certain magnetic frequencies, the chain will split into two separate smaller chains which move independently of one-another.

After being separated, the field can be adjusted to make the smaller robots travel in different directions. The beads can also be reconnected as they are magnetized. This is achieved by tweaking the field to bring them back into contact.

This finding is a vital part of a bigger project in which Drexel is collaborating with 10 institutions of medicine and research from across the world to develop technology for executing minimally invasive surgery on blocked arteries."

Source: AZO Robotics, Drexel