2022 Volume 19 Issue 9 Pages 20220094
Breathing monitoring is important in the health and sports area. In this paper, a wireless self-powered health system for breathing monitoring is designed using the piezoelectric devices and buckled n-shape and L-shape structure. A cotton belt is used to tie the system to the chest and deliver the force stimulated by the chest cavity enlargement caused by the breathing, which can be collected and measured based on the three-dimension n-shape and L-shape structure. Three hard lead zirconate titanate (PZT) patches are used as the energy source to support the sensing circuit and soft piezoelectric polyvinylidene fluoride (PVDF) works as the sensor to measure the stretching force, which are placed at the gap between the 3D-printed n-shape and L-shape structure, making the measurement more precise. Breathing signal comparison between commercially used battery-powered respiration belts shows the efficiency of the piezoelectric devices on the accuracy, precision, and recall factors. The system is also used in practical experiments and it is found that the intense actions have a similar peak-peak value of breathing wavefront but a much higher frequency of respiration. This design can be used in health monitoring and sports training, which also shows the potential of data acquisition for disease diagnosis applications.
