Sensors MIT engineers have shown that they can use magnetic fields to track the location of this ingestible sensor within the GI tract. (Image: Courtesy of the researchers) The sensor could be used to monitor GI motility disorders such as constipation or gastroesophageal reflux disease. (Image: Courtesy of the researchers) measures the field, we can back-calculate what the location of the device is. " To accurately pinpoint a device's location inside the body, the system also includes a second sensor that remains outside the body and acts as a reference point. This sensor could be taped to the skin, and by comparing the position of this sensor to the position of the sensor inside the body, the researchers can accurately calculate where the ingestible sensor is in the GI tract. The ingestible sensor also includes a wireless transmitter that sends the magnetic field measurement to a nearby computer or smartphone. The current version of the system is designed to take a measurement any time it receives a wireless trigger from a smartphone, but it can also be programmed to take measurements at specific intervals. The current version of the sensor can detect a magnetic field from electromagnetic coils within a distance of 60 cm or less. The researchers envision that the coils could be placed in the patient's backpack or jacket, or even the back of a toilet, allowing the ingestible sensor to take measurements whenever it is in range of the coils. For more information, contact Sarah McDonnell at s_mcd@ mit.edu; 617-253-8923. 40 www.techbriefs.com Tech Briefs, November 2023http://info.hotims.com/84485-730 http://info.hotims.com/84485-731 http://www.techbriefs.com