fig4

Figure 4. Integration of sensor unit on airbag pillow for snoring monitoring. (A) Photograph showing one single sensor unit mounted on the top layer of one airbag; (B) Flowchart illustrating the acquired signal processing process and a photograph showing the home-made circuit board of the electromechanical system; (C) Relative current change curve upon different internal pressures of the airbag; (D) Photograph showing the lie-down and sit activities and corresponding response signals. Comparison of response signals obtained from different snoring modes of (E) normal regular snoring and (F) abnormal long snoring.