Conductive cold-resistant and elastic hydrogel: A potential bionic skin for human-machine interaction control over artificial limbs

This work enables conductive cold-resistant and elastic hydrogel for a new application in electric steering engine control, demonstrating a great potential as bionic skin for goal-directed control over artificial limbs. The photocrosslinking of acrylamide provides an elastic matrix that is functionally improved by physical crosslinking of K₂CO₃, carrageenan and locust bean gum. The hydrogel is highly elastic with the stress of 0.04 MPa at 650% strain, and can recover immediately after being stretched to 500% or pressed to 10% of its original length. It can keep its softness and conductivity at a low temperature of −10 °C. When an intermittent bending force is applied, it synchronously outputs the resistance variation signals between 1.1 and 0.9 times the original value. We take advantages of all these physical features to create a soft controller for the convenient manipulation of electric steering engine. We translate the bending-induced resistance variation signals into digital data of between 0 and 1023, which are then encoded to direct the electric steering engine for various controlled motility. A simple bending of hydrogel can activate the electric steering engine in 0.18 s, showing a highly-synchronous control over the dynamic response of electric steering engine in many models.