Researchers at Purdue University have found a means by which to control individual microbots within groups, a feat never before accomplished, using technology that the researchers themselves related to “mini force fields.”
David Cappelleri, an assistant professor of mechanical engineering at the university, stated that he and his colleagues employed “magnetic fields to generate forces on the robots” that are “like using mini force fields.”
The robots are too small to put batteries on them, so they can’t have onboard power […] You need to use an external way to power them. We use magnetic fields to generate forces on the robots. It’s like using mini force fields.
In order to pull off the feat, the researchers, whose recent findings were published in the journal Micromachines, developed a system employing planar coils in a new fashion. Instead of planting the coils around the perimeter of the microbots and creating a globalized field, the planar coils are printed directly onto the substrate– creating a localized field.
Cappelleri explained that the new approach “works at the microscale” and it’ll be the first to offer “truly independent motion of multiple microbots in the same workspace”.
The approach we came up with works at the microscale, and it will be the first one that can give truly independent motion of multiple microrobots in the same workspace because we are able to produce localized fields as opposed to a global field […] What we can do now, instead of having these coils all around on the outside, is to print planar coils directly onto the substrate.
According to the university, the breakthrough in independent microbot control could prove useful in building microelectromechanical systems (MEMS) — tiny machines with applications ranging from homeland security to medicine.
The microbots used by the researchers in their latest study were roughly 2 millimeters in diameter, which is approximately twice the size of a pinhead. Researchers plan on eventually reducing the size of microbots down to a diameter of 250 microns – about the size of the cosmopolitan pyroglyphid known as the house dust mite.
The team of researchers behind the discovery, who are continuing their research, intend on trying to create components for MEMS devices using microscale prototypes, but they may run into an issue that only becomes apparent when working on a micron level, as the effect of van der Waals forces between the molecules could create static friction between them.
The research was funded by grants provided by the National Science Foundation (NSF).
