Did you hear about the “belly bands”, the ultra smart fabric that has been designed to help women with complicated pregnancies. Integrated with RFID technology, it is a highly comfortable and stretchable fabric that women carrying foetus wear over their abdomens. These actually serve as sensors that are capable of monitoring respiration patterns, contractions, as well as limb movements. These keep a track of data and caution the doctors in case of emergency.
These belly band sensors are formed from folded dipole antenna that are equipped and coupled with passive RFID tag. It basically uses an in-built RFID reader that is very much similar to a baby monitor for tracking and sending data from band. The sensor works with the help of returned signal strength indication (RSSI) from the RFID backscatter to find the deformation of the fabric. As and when the shape of antenna alters, for example by the breathing pattern, a shift is experienced in the resonance frequency. This leads to a variation in RSSI that can be checked over the reader, offering a way to track alterations in the female’s body with the help of machine learning techniques.
According to Kapil Dandekar, the electrical and computer engineer, “We’re looking at making antennas out of knitted conductive materials. As those antennas stretch due to, say, uterine contraction in a pregnant woman or infant respiration, we can detect changes in signal characteristics that come off of that antenna and process that to infer what’s happening biologically.” The usage of a passive RFID technology implies that there is no requirement for battery inside the sensor, however, this is a single step in the making of belly band that is suitable for regular usage. It is for this reason, the fashion industrial designer, Genevieve Dion is looking for ways to make the sensor practical as well as comfortable.
Dion says, “If it doesn’t fit well, you’ll be tugging on it, and you won’t want to wear it, and then it’s useless. But also if it doesn’t interact well, then it’s a gadget, because you have to fuss with it. So I think it has to be well-designed so that we can be comfortable in them, but it also has to be well-engineered in many ways so that it functions properly.”