MIT engineers have created soft, 3-D-printed structures whose movements can be controlled with a wave of a magnet, much like marionettes without the strings.
The menagerie of structures that can be magnetically manipulated includes a smooth ring that wrinkles up, a long tube that squeezes shut, a sheet that folds itself, and a spider-like “grabber” that can crawl, roll, jump, and snap together fast enough to catch a passing ball. It can even be directed to wrap itself around a small pill and carry it across a table.
The researchers fabricated each structure from a new type of 3-D-printable ink that they infused with tiny magnetic particles. They fitted an electromagnet around the nozzle of a 3-D printer, which caused the magnetic particles to swing into a single orientation as the ink was fed through the nozzle. By controlling the magnetic orientation of individual sections in the structure, the researchers can produce structures and devices that can almost instantaneously shift into intricate formations, and even move about, as the various sections respond to an external magnetic field.
Xuanhe Zhao, the Noyce Career Development Professor in MIT’s Department of Mechanical Engineering and Department of Civil and Environmental Engineering, says the group’s technique may be used to fabricate magnetically controlled biomedical devices.
“We think in biomedicine this technique will find promising applications,” Zhao says. “For example, we could put a structure around a blood vessel to control the pumping of blood or use a magnet to guide a device through the GI tract to take images, extract tissue samples, clear a blockage, or deliver certain drugs to a specific location. You can design, simulate, and then just print to achieve various functions.”
Zhao and his colleagues have published their results today in the journal Nature. His co-authors include Yoonho Kim, Hyunwoo Yuk, and Ruike Zhao of MIT, and Shawn Chester of the New Jersey Institute of Technology.
thumbnail courtesy of news.mit.edu