Highly Sensitive Wearable Flexible Pressure Sensor Based on Conductive Carbon Black/Sponge

At present, more and more flexible pressure sensors are used in wearable devices. The improvement of the adsorbability of nanomaterials on sponge flexible pressure sensors is an urgent problem to be solved. Here, using conductive carbon black with good dispersibility and small particle size as the conductive filler filled in the middle of the sponge can improve the absorbability of the sponge. A simple method of soaking a sponge with different thicknesses in conductive carbon black dispersion is used to obtain flexible pressure sensors based on conductive carbon black/sponge. We compare and analyze the differences in initial resistance and sensitivity of sponge pressure sensors with different thicknesses and select the sensor with higher sensitivity (0.194 kPa ⁻¹ ) for response time, recovery time, and stability tests. The sensor is used in the neck, wrist, knee, and other body parts for motion recognition. The two conductive carbon black/sponge sensors are placed orthogonally on the back to identify nod, tilt head, and placed on the elbow to test the angle of arm bending. Conductive carbon black/sponge flexible pressure sensor shows good application prospects in the wearable field.