Research on the Monitoring of Human Acoustic Field Signals Based on Gelatin-Based Hydrogel Sensors

In this paper, natural gelatin is used as a substrate for flexible sensors, and hydrogel films are prepared using the hybrid cross-linking technique. However, natural gelatin films used directly as substrates for human wearable devices suffer from temperature inadaptation and poor film formation. By adding k-carrageenan, modified starch and potassium chloride solution as cross-linking agents to the gelatin solution, the crosslinking reaction results in the formation of stable chemical bonds between the gelatin molecular chains. This leads to the formation of a three-dimensional network structure in the hydrogel and enhances its ionic conductivity. Increasing the hydrogel solidliquid phase transition temperature threshold to 44° C makes hydrogel sensors a more suitable wearable device. The sensor, worn in a wearable form, conducts stress sensing detection. With real-time monitoring of human sound field signals, the oscilloscope displays reproducible characteristic signal patterns, indicating excellent sensing performance. Gelatin-based hydrogel sensors have promising applications in human sound field signal monitoring.