In a new study published in Science Advances a team of engineers at The Chinese University of Hong Kong outlines how it has created small-scale soft robots capable of multimodal locomotion, drug cargo delivery, and the ability to tolerate exposure to acid. A prime use case for the small-scale robots—which are tens of millimeters across depending on their shape—is, according to the engineers, “for biomedical applications that involve operation in the stomach such as gastric ulcer treatment.” As a proof-of-concept for the study, the researchers even had one of the small, soft robots roll around in an ex vivo pig’s stomach and apply a “therapy patch.”
In their study the engineers describe how their small-scale robots utilize a “modular soft magnetic architecture” with individual parts of the robots containing magnetic microparticles that each have their own prescribed magnetization profiles—that is, they each respond to their own type of magnetic field depending on the directionality of the field.
These “modular magnetization units” are embedded into a “network of adhesive sticker layers” in order to form the soft robots, which are capable of taking on either 2D or 3D shapes. “Functional” modules consisting of different materials, and having different shapes—e.g., particles, papers, films, foams, and electronic components—can then be “seamlessly integrated” into the small-scale robots.