Fig. 1.

Wireless, soft, skin-interfaced platform designed for vocal fatigue monitoring with haptic feedback. (A) Simplified illustration of the platform operation. A MA sensor mounts on the upper chest, below the SN, for real-time data acquisition of signals related to vocal, cardiac, respiratory, and overall physical activities. A wrist band provides haptic feedback. The user interface supports signal analysis by machine learning to monitor vocal fatigue and to generate graphical and haptic forms of feedback to the user. (B) Representative data from continuous monitoring: MA signal, spectrogram, cumulative vocal energy dose, vocal intensity.