McGill University engineers have developed new ultra-thin materials that can be programmed to move, fold and reshape themselves, much like animated origami. They open the door to softer, safer and more adaptable robots that could be used in medical tools that gently move inside the body, wearable devices that change shape on the skin or smart packaging that reacts to its environment.
The research, jointly led by the laboratories of Hamid Akbarzadeh in the Department of Bioresource Engineering and Marta Cerruti in the Department of Mining and Material Engineering, shows how simple, paper-like sheets made from folded graphene oxide (GO) can be turned into tiny devices that walk, twist, flip and sense their own motion. Two related studies demonstrate how these materials can be made at scale, programmed to change shape and controlled either by humidity or magnetic fields.
"Graphene oxide films are highly promising for next-generation soft robots and adaptive actuators, yet their real-world deployment remains limited because they are brittle, challenging to manufacture at scale and unable to generate complex or programmable motion," said Cerruti. An actuator converts energy into motion to produce controlled movement or functionality.
The team created GO films that are strong and flexible. These materials are well suited for use in soft robots, which need to be lightweight, safe around people and capable of moving in complex ways without heavy motors or rigid parts.
The researchers used the GO films to create structures that may respond to everyday environmental conditions. In the first study, the origami-like structure opens when exposed to humidity and closes again as it dries. In the second study, similar kinds of shapes were combined with tiny magnetic particles so they can be remotely steered using a magnet, without wires or batteries.
The graphene oxide layer's inherent ability to conduct electricity in a way that changes as the material bends allows the folded structures to sense their own movement, the researchers found. This allows the structures to act simultaneously as actuators that move and sensors that measure movement.
"These advances enable robust, reconfigurable and multifunctional GO metamaterials capable of complex motion, user-defined shape changes, integrated sensing and real-time feedback, marking the emergence of the first reconfigurable sensoriactuator metamaterials" Akbarzadeh said.
About the studies
"Strong and flexible graphene oxide paper for humidity responsive origami metamaterials," by Yiwen Chen, Jun Cai, Alireza Seyedkanani, Abdolhamid Akbarzadeh and Marta Cerruti, was published in Materials Horizons. https://doi.org/10.1039/D5MH01681A
"Multifunctional and Reprogrammable Magnetoactive Graphene Oxide Origami," by Jun Cai, Yiwen Chen, Alireza Seyedkanani, Guocheng Shen, Marta Cerruti and Abdolhamid Akbarzadeh, was published in Advanced Science. https://doi.org/10.1002/advs.202514597
The projects have been supported by the New Frontiers in Research Fund, the Canada Research Chairs program in Multifunctional Metamaterials, NSERC Discovery Grants, the Canada Foundation for Innovation, an FRQNT doctoral scholarship, and McGill University.
