In a National Science Foundation-backed project, researchers from American, Japanese, and Korean universities are pioneering a technique for creating 3D printed soft robotic devices. It is hoped that the technology could someday be used to create realistic robotic muscles.
Robots—3D printed or otherwise—can do some pretty impressive things: clean your house, build a car, and even hold a basic conversation. Typically, however, such machines have been limited by one particular feature: their rigidity. While human beings can perform all kinds of dextrous operations thanks to our spongy nature, robots tend to be made of solid, non-deforming materials, preventing them from maneuvering in tough spaces or performing smooth motions. The emerging field of soft robotics, however, is beginning to embrace new, flexible robotic materials, designed to open up a new world of technological possibilities.
One important goal for many soft roboticists is the creation of robotic muscles, which could someday be used to create realistic and functional prosthetic limbs, amongst other things. For although there are many realistic robotic hands (and other body parts) out there, many of them completely forsake biomimetic realism in favor of kinetic realism; they look like they’re human but don’t work in a human way. While these robots can achieve incredible things, it is difficult to effectively incorporate them into a human body.
Kwang Kim, a professor at the University of Nevada, Las Vegas, recently embarked upon a large collaborative project to create realistic robotic muscles which could be used to revolutionize prosthetic devices for disabled people. To do so, he not only had to identify the most suitable material, but also had to determine how best to control and manufacture it. For the latter problem, the professor and his National Science Foundation-funded team sought the help of 3D printing.
First and foremost, Kim and his team needed to identify a material that would be flexible and strong enough to function like a muscle, as well as being controllable via electronic means. While there were many options at the researchers’ disposal, they decided to use something with a bit of extra spark: Ionic Polymer-Metal Composites. This synthetic material is an electroactive polymer, which means that electricity can be used to alter its shape. “In robotics you’ve got to be able to move and you’ve got to be able to sense,” said Kam Leang, an associate professor at the University of Utah Robotics Center and co-investigator on the project. “In this PIRE, we are using the electroactive polymer itself.”
Using an electroactive polymer actually offers two advantages to the researchers. Not only can the material be controlled with electrical currents, it can also be used to sense motion. Better still, the researchers even found a way to 3D print the material, so they could create precisely shaped robotic components from the material. The researchers are currently working on ways to scale up the 3D printing process and discover new ways to control the motion of the polymer. Since soft robotics remains a relatively new field, nobody is quite sure what they will discover next: “I’m learning every day,” said Kim.
The 3D printing research was supported by NSF‘s Partnerships for International Research and Education (PIRE) program. Other participants in the project included researchers from the Korea Advanced Institute of Science and Technology (KAIST) and Japan’s National Institute of Advanced Industrial Science and Technology.