Systems and Methods of Multi-modal Wearable Sensor for Patient Monitoring

A device having a processor and an addressable memory comprising:

• an acoustic sensor module for a wearable medical device, the acoustic sensor module comprising:
• an acoustic impedance-matched diaphragm formed of thermoplastic elastomer, the diaphragm configured to substantially match the acoustic impedance of human tissue;
• a semi-flexible metallic backing plate disposed adjacent to the diaphragm;
• a piezoelectric element, comprising a piezoelectric transducer positioned to receive acoustic energy transmitted through the diaphragm and backing plate;
• a signal electrode operatively coupled to the piezoelectric transducer;
• a closed-cell polyethylene foam backing disposed beneath the transducer and electrode;
• and
• a printed circuit board (PCB) supporting the assembly;
• wherein the acoustic impedance-matched diaphragm is configured to maximize transmission of physiological sounds from the body to the acoustic sensor and to minimize transmission of airborne and ambient noise by reflecting environmental noise at the impedance interface;
• and
• wherein the acoustic impedance-matched diaphragm is integrated into a housing structure of the wearable medical device, such that the diaphragm serves both as an acoustic coupling medium and as a protective enclosure providing ingress protection against liquids and particulates.