Flexible acoustic sensor systems

A method of operating a flexible acoustic sensor apparatus, the method comprising:

• controlling a first group of acoustic sensor elements of the flexible acoustic sensor apparatus to transmit acoustic signals toward an object of interest;
• receiving, at a second group of acoustic sensor elements of the flexible acoustic sensor apparatus, reflected acoustic signals from the object of the interest;
• and
• performing one or more beamforming techniques with the transmitted acoustic signals and the reflected acoustic signals, the one or more beamforming techniques comprising:
• row-column driving based on the transmission of the acoustic signals by the first group of acoustic sensor elements and the receipt of the reflected acoustic signals by the second group of acoustic sensor elements;
• a delay-and-sum beamforming process comprising applying a time delay to one or more of the received reflected acoustic signals, and summing the received reflected acoustic signals;
• division of a plurality of pixelated sensor elements into subarrays;
• positioning at least a portion of the plurality of pixelated sensor elements at different heights;
• or
• a combination thereof.

An acoustic sensing apparatus comprising:

• a flexible substrate comprising polyimide and having a thickness between 5 and 80 μm;
• and
• a first flexible acoustic sensor element disposed adjacent to the flexible substrate and comprising a first plurality of pixelated sensor elements;
• a second flexible acoustic sensor element disposed adjacent to the flexible substrate and comprising a second plurality of pixelated sensor elements;
• and
• a coupling layer configured to secure the flexible substrate to a body part of a user having a target object;
• wherein the flexible acoustic sensor element is communicatively coupled with at least one control system, and the at least one control system is configured to determine, based on one or more first acoustic signals received at the first plurality of pixelated sensor elements, and one or more second acoustic signals received at the second plurality of pixelated sensor elements, a physiological characteristic associated with the target object.