EnteroPhone™ is an ingestible electronic capsule about the size of a multivitamin, yet it contains an array of advanced sensors that can monitor a person's vital signs from inside the body. EnteroPhone™ listens to heart and lung sounds, and it measures body core temperature, movement, and gastrointestinal pressure. A custom piezoelectric hydrophone assembly, thermistor, accelerometer, and barometer are built into EnteroPhone™ to capture these biosignals. These data are processed on-board the capsule within the gastrointestinal tract, then transmitted wirelessly to an external processor that delivers reliable, useful information about a person's physiological status. EnteroPhone™ could give physicians, physical therapists, and athletic trainers a tool that monitors a person's vital signs without using uncomfortable external sensors or surgically implanted devices. A team from Lincoln Laboratory and MIT campus developed and tested this technology.