The latest findings from a team of researchers at Massachusetts Institute of Technology (MIT) show magnetic, 3D printed creatures capable of rolling, crawling, creeping, folding and catching objects, without any “strings” attached.
Made from a new type of soft material, these incredibly lifelike structures have virtually limitless potential in intelligent robot development, especially within the field of medicine.
“There is no ideal candidate for a soft robot that can perform in an enclosed space like a human body, where you’d want to carry out certain tasks untethered,” explains Yoonho Kim, co-author of a paper explaining the discoveries.
“That’s why we think there’s great promise in this idea of magnetic actuation, because it is fast, forceful, body-benign, and can be remotely controlled.”
Soft robotics and 4D printing
The developing field of soft robotics is affording scientists the opportunity to create more flexible, and therefore more versatile, machines. Soft robots, like Harvard University’s well-known Octobot, are designed to move using mechanisms that more closely resemble living organisms.
“Living” mechanisms, like muscles, are often replicated by hydraulic or pneumatic power. However, to make these systems more intelligent, and adaptable, they need to be activated with little input from a human operator.
4D printing, i.e. 3D printing materials that autonomously transform, is one area that is discovering new ways of “hands free” activation. But, at present, the process often takes too long, and it isn’t easily reversible.
Timelapse showing a 4D printed tetrahedron assembling when heat is applied. Clip via ETH Zurich Engineering Design and Computing Laboratory on YouTube
Magnetic 3D printing
MIT’s magnetic objects are 3D printed on a specially designed platform, from a newly-formulated ink infused with magnetic particles.
The platform hosts a 3D printer nozzle in the center of an electromagnet, which is used to control the orientation of particles in the ink. When deposited, the ink flows much like the perfect cake frosting.
With magnetic particle control, combined with a flexible material, the researchers are capable of programming a 3D printed shape to move in a certain way when a field is applied.
Xuanhe Zhao, the study’s lead author believes that objects developed in this latest research could find promising application in the field of biomedicine, much like other micro robots.
“For example,” Zhao explains, “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 […]”
“You can design, simulate, and then just print to achieve various functions.”
To explore the full range of possibilities open to these devices, the MIT team has made the predictive model used to make creatures available for others to use.
“Printing ferromagnetic domains for untethered fast-transforming soft materials” is published online in nature journal. It is co-authored by Yoonho Kim, Hyunwoo Yuk, Ruike Zhao, Shawn A. Chester and Xuanhe Zhao.
Featured image shows a snowflake shaped, 3D printed magnetic structure with spider-like abilities. Clip via MIT/nature