Hot soft robot fingers made of liquid crystals and graphene
June 18, 2024 – Researchers from Eindhoven University of Technology (TUE) have developed an innovative robotic hand, made of liquid crystals and graphene, intended for surgical applications. Soft robots can make precise and delicate movements in surgery, which stiff robots can do only to a limited extent. The team created a gripper with four flexible fingers by combining liquid crystals with graphene, resulting in an actuator that controls motion in robotic systems. The movement of these actuators is powered by heat, generated via graphene heating elements. Electric current through these elements changes the molecular structure of the liquid crystals, causing the fingers to bend. When the flow stops, the fingers cool and return to their original shape.
A major challenge was achieving the right temperature without overheating. After various tests, the researchers developed an actuator that works safely at voltages below 15 volts. The robot hand can lift small objects between 70 and 100 milligrams. This research, published in June in ACS Applied Materials & Interfaces under the title “Hot Fingers: Individually Addressable Graphene-Heater Actuated Liquid Crystal Grippers.”