Self-Healing Ionic Gelatin/Glycerol Hydrogels for Strain Sensing Applications

Soft sensing technologies have the potential to revolutionize wearable devices, haptic interfaces and robotic systems. However, there are numerous challenges in their deployment due to their poor resilience, high-energy consumption, and omnidirectional strain responsivity. This work reports the development of a versatile ionic gelatin-glycerol hydrogel for soft sensing applications. The sensing device is cheap and easy to manufacture, self-healable at room temperature, can undergo strains of up to 454%, is stable over long periods of time, biocompatible and biodegradable. It is ideal for strain sensing applications, with R^2 = 0.9971 linearity and a pressure insensitive conduction mechanism. Experimental results show the applicability of the ionic hydrogel for wearable devices and soft robotic technologies for strain, humidity and temperature sensing, while being able to partially self-heal at room temperatures.SHERO project, a Future and Emerging Technologies (FET) programme of the European Commission (grant agreement ID 828818). EPSRC DTP (EP/R513180/1)