Utilizing Origami Integrated Piezoelectric Foil Acoustic Emission and Acceleration Sensor Fused with Omnidirectional Motion Detector For Knee Joint Health Monitoring

This paper presents a new type of wearable piezoelectric multifunctional knee joint health monitoring module. This module can detect acoustic emission waves (AE), acceleration, and knee motion near the knee joint without additional power supply. The module consists of two parts, one part is the motion sensor and the other part is the AE and acceleration integrated sensor, both based on micro-machined piezoelectric film and 3D printed base, achieving the sensing of motion, AE and acceleration through the three-dimensional structure combined with the origami technology. Experimental results verify the functionality of the fabricated devices. We successfully acquired the signals of AE and acceleration at a specific position on knee joint and signals of knee joint moving from different statuses when a subject wearing the developed module performs the knee joint motions.