Scientists use 'mini force fields' to control individual microbots; could lead to the development of tiny machines for medicine and manufacturing

A team of engineers at Purdue University have found a technique to control individual robots operating in a group using “mini force fields.” The researchers are hopeful that the technique would allow development of tiny machines used in the field of medicine and manufacturing.

What makes this technique unique is its ability to control individual microbots. Until now, it was only possible to control the entire group of microbots together to move in unison. No individual-level intervention was possible.

Researcher David Cappelleri says that the reason why the team wants to control each microbot individually is to enable them to do cooperative manipulation tasks.

"Think of ants. They can independently move, yet all work together to perform tasks
such as lifting and moving things,” said Cappelleri, reports Phys.org. “We want to be able to control them individually so we can have some robots here doing one thing, and some robots there doing something else at the same time."

During the research, the team developed a mechanism for “controlling the robots with individual magnetic fields from an array of tiny planar coils.” Since the microbots are so tiny to have a power source embedded on them, the team used external magnetic fields to generate forces on the microbots. The researchers refer to these external magnetic fields as mini force fields.

The systems developed previously used fewer coils around the perimeter of the workspace containing microbots to control them. However, the field produced by them is not enough to control individual robots.

The new system developed by the Purdue University team works at microscale level and is able to produce local field rather than a single “global” field. The local fields control independent motion of multiple robots within the same workspace. The team is now planning to print planar coils directly onto the substrate, rather than to have the coils along the perimeter of the workspace.

The complete details of the research have been published this month in the journal Micromachines.