A research team at University of Sussex in the UK has developed a strain sensor capable of detecting a touch as gentle as a feather. Their device was made using networks of graphene nanosheets placed in a flexible polymer matrix, Physics World writes. The hypersensitive material could have applications in the medical and robotics fields.
Polydimethylsiloxane, or PDMS, is a highly flexible biocompatible, transparent polymer being eyed for use in the current generation of strain sensors. But due to the twisting of molecules within the material making it an uneven distributor of nanoparticles, it has yet to find widespread mainstream use.
The University of Sussex team has figured out a way to process PDMS using graphene nanosheets assembled to stabilize oil droplets containing molecules of PDMS. By making various adjustments, the researchers were able to alter the material’s molecular structure to create “highly elastic films containing large quantities of conductive graphene nanosheets.”
Their material was sensitive to strains ranging from 0.1% to over 80%, a considerable improvement over today’s best strain sensors. Such technology could revolutionize healthcare applications where accurate strain measuring is critical, such as patient breathing and heart rate.