Triboelectric Pressure Sensor With Microstructured PDMS for Human Motion and Gait Pattern Monitoring

This work presents a low-cost, out-of-cleanroom method for fabricating microstructured polydimethylsiloxane (PDMS) films for triboelectric pressure sensors, using a tape mold replication process that eliminates the need for expensive equipment. A triboelectric nanogenerator (TENG)-based pressure sensor is developed with materials, including PDMS, polyimide (kapton) films, and copper electrodes. The TENG-based pressure sensors have been successfully applied to monitor various human motions, such as walking (via insole integration), tactile sensing (via cup integration), foot pressure detection, and tracking movements such as elbow and finger bending, as well as jumping. The flexible sensor demonstrated high linearity (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$R^{2} =0.9817$ </tex-math></inline-formula>), a quick response time (100 ms), and a reliable loading and unloading rate (10 Hz). The sensor showed stable output across diverse forces and frequencies, which is ideal for flexible and wearable applications. These findings highlight the potential of the proposed TENG fabrication method for applications in wearable pressure sensors, self-powered electronic skin (e-skin) for humanoid robots, and human--machine interaction systems.