Researchers at Thayer School of Engineering at Dartmouth College and City University of Hong Kong have developed a light-controlled, shape-changing robot by combining a light-sensitive gel, cardiac tissue engineering and a 3D-printed wing structure. The robot can be made in a variety of different sizes rendering it totally flexible to execute navigation and surveillance tasks in any situation, and capable of delivering drugs more precisely within the body. The robot is driven by a tail fin that mimics the swimming action of whales, and transforms its shape when exposed to skin-penetrating near-infrared light, causing it to start and stop through fluid. The structure was 3D printed in the shape of an airplane wing and then coated with heart muscle cells. Photosensitive hydrogels were applied to the wings to control the movement. In the absence of light, the wings deploy, allowing the heart cells to propel it forward. When exposed to light, the floating plane retracts its wings, causing it to stop, and its sensitivity to near-infrared light means the wing shape is transformed almost instantly.

Zi Chen, an assistant professor of engineering at Thayer, said: “With this technology we can create soft transformable robots with unprecedented manoeuvrability. The heart muscles keep churning, but they are unable to overcome the stopping power of the wings. We literally dropped drug bombs on cancer cells. The realisation of the transformable concept paves a pathway for potential development of next-generation intelligent biohybrid robotic systems.”

“Light-controlled robot could facilitate precise drug delivery. “

Xiaomin Han, a recent PhD graduate from the Chen Research Lab at Thayer, said: “The ability to control the robot’s motion using light creates a much more functional device that can be operated with high precision.”