Shape-changing electronics for wearable applications

A research team led by the Korea Advanced Institute of Science and Technology (KAIST) has developed a multifunctional electronic platform that can mechanically transform its shape, flexibility and stretchability. The platform, dubbed ‘Transformative Electronics Systems’ and described in the journal Science Advances, allows users to seamlessly and precisely tune its stiffness and shape.

“This new class of electronics will not only offer robust, convenient interfaces for use in both tabletop or handheld set-ups, but also allow seamless integration with the skin when applied onto our bodies,” said Professor Jae-Woong Jeong, who led the research.

The transformative electronics consist of a special gallium metal structure, hermetically encapsulated and sealed within a soft silicone material, combined with electronics that are designed to be flexible and stretchable. The mechanical transformation of the electronic systems is specifically triggered by temperature change events controlled by the user.

“Gallium is an interesting key material,” said KAIST researcher Sang-Hyuk Byun, lead author of the study. “It is biocompatible, has high rigidity in solid form and melts at a temperature comparable to the skin’s temperature.”

Once the transformative electronic platform comes in contact with a human body, the gallium metal encapsulated inside the silicone changes to a liquid state and softens the whole electronic structure, making it stretchable, flexible and wearable. The gallium metal then solidifies again once the structure is peeled off the skin, making the electronic circuits stiff and stable. When flexible electronic circuits were integrated onto these transformative platforms, it empowered them with the ability to become either flexible and stretchable or rigid.

“This technology could not have been achieved without interdisciplinary efforts,” said co-lead author Joo Yong Sim, a researcher at Korea’s Electronics and Telecommunications Research Institute (ETRI). “We worked together with electrical, mechanical and biomedical engineers, as well as material scientists and neuroscientists, to make this breakthrough.”

The universal electronics platform allowed researchers to demonstrate applications that were highly adaptable and customisable, such as a multipurpose personal electronics with variable stiffness and stretchability, a pressure sensor with tuneable bandwidth and sensitivity, and a neural probe that softens upon implantation into brain tissue.

Applicable for both traditional and emerging electronics technologies, the breakthrough could potentially reshape the consumer electronics industry, especially in the biomedical and robotic domains. The researchers believe that with further development, this novel electronics technology can significantly impact the way we use electronics in our daily life.

Image caption: Transformative electronics in soft mode — wearable for outdoor applications.

Please follow us and share on Twitter and Facebook. You can also subscribe for FREE to our weekly newsletter and bimonthly magazine.