Ben Evans, associate professor of physics, is part of a research team looking into developing the new technology that could have application in the biomedical and aerospace fields.
鈥婲ewly published research by a team including聽Associate Professor of Physics Ben Evans and researchers from N.C. State University聽shows the possibility of controlling soft robots with light and magnetic fields, with the new technique to likely be applied to the biomedical and aerospace fields.
In a paper published Aug. 2 in the journal Science Advances titled the research team聽demonstrated for the first time the ability to remotely control soft robots, lock them into position and later reconfigure them into new shapes or have the robot return to its original shape.
鈥淎n important aspect of all this work is being able to manipulate materials in a non-contact way,鈥 said Evans, who was integral to the modeling and simulation work on the project, which is supported by grants from the National Science Foundation.
The team previously demonstrated the ability to remotely control soft robots 鈥 devices made from highly flexible materials that function similar to living organisms 鈥 using magnetic fields. The technique allows for devices to be moved without having to rely upon electricity or pneumatic force.
The big step forward with the research now is the ability to use light to control whether the robot is flexible or rigid, and to then have the robot return to its original shape. The researchers used soft robots made of a polymer embedded with magnetic iron microparticles that is stiff and holds its shape under normal circumstances.
Shining an LED light on the robot makes the robot pliable, and when a magnetic field is then applied, the robot can be manipulated into different shapes. Once the light is removed, the robot again becomes rigid and holds its shape, even when the magnetic field is removed. Shining the light again on the robot again causes it to return to its original shape, or if a magnetic field is also applied again, the robot can be moved into a different shape.
鈥淭he shape memory effect is a new piece,鈥 Evans said.
During testing, the team demonstrated that soft robots can be used to form 鈥済rabbers鈥 for lifting and transporting objects. They can also be used as cantilevers or folded into 鈥渇lowers鈥 with petals that can bend in different directions. During experiments, the researchers used a 鈥渇lower鈥 robot to grab and hold a blueberry and a cherry tomato before releasing them.
Evans is excited about the potential to deploy this new technology in the biomedical field, particularly in medical diagnostic devices. Advances are being made in producing a 鈥渓ab on a chip鈥 that integrates several laboratory functions on a small circuit that is no larger than a few square centimeters and likely smaller. Evans said the team鈥檚 research could allow for the magnetic manipulation of small channels of liquid on the chip, essentially opening and closing valves and doorways.
This research has established a foundational model that will now allow for the robot鈥檚 shape and composition to be fine-tuned, with ongoing research focusing on how to use magnetic fields to manipulate the robot鈥檚 shape in new ways.
鈥嬧淲e鈥檙e at the point where we鈥檙e exploring what鈥檚 possible,鈥 Evans said.
The work was conducted in collaboration with Jessica Liu, Jonathan Gillen, Sumeet Mishra, and Professor Joseph Tracy of N.C. State University with support from the National Science Foundation (NSF) under grants CMMI-1663416 and CMMI-1662641. The work was also supported by the Research Triangle MRSEC, which is funded by NSF under grant DMR-1121107; and by NC State鈥檚 Analytical Instrumentation Facility and the Duke University Shared Materials Instrumentation Facility, which are supported by the State of North Carolina and NSF grant ECCS-1542015.