SteadySense has developed an intelligent temperature measuring solution for medical applications


SteadySense, develops femSense® technology – an innovative and smart temperature measuring solution for medical applications. One key drawback of non-invasive intermittent temperature measurements is that sudden temperature increases – indicating an infection following an operation, for example – are not recorded. By contrast, continuous temperature checking for up to seven days with femSense is an ideal solution, e.g. for identifying fertile days when trying to have a baby or for patient monitoring in hospitals. AT&S was involved in the development process from the beginning – from the feasibility study to product development and production. SteadySense benefited not only from leading printed circuit board (PCB) technology from AT&S, but also from their extensive system expertise, especially in the medical sector.

Apart from the circuit logic, the femSense smart sensor system essentially comprises a temperature-sensitive fully integrated sensor. The thermometer patch is applied under the armpit and is activated using a smartphone. The high-tech patch measures and then continuously saves current body temperature values at specified time intervals. If required, measured values can be read out using an NFC (near-field communication) capable smartphone, then analyzed and displayed in a specially developed app. The result is accurate, simple, continuous and discreet temperature measurement.

Help when trying to conceive

The first application for the femSense sensor patch focuses on calculating ovulation based on the user’s basal body temperature. The goal is to increase the chances of getting pregnant for women who are trying to conceive. A correlation between the increase in body temperature and the time of ovulation has been known for almost 100 years. The innovation is that the femSense patch measures temperature continuously and accurately. Unlike intermittent measurements (e.g. once a day), this allows a precise temperature curve to be calculated, significantly increasing this method’s reliability.

The one-time use of the adhesive patch minimizes infection risks. In addition to the sensor patch, SteadySense also provides the app and all interfaces to the central database. femSense is an ISO 13485 certified medical product.

Compact design with flexible PCB

The convenient and compact femSense patch is based on circuitry using a flexible PCB from AT&S that fits comfortably on the wearer’s body. Flexible printed circuit boards are now in use throughout the electronics industry. The circuit board is generally installed bent, twisted or folded. Flexible PCBs can be used to create configurations and geometries – as in femSense patches, for example – that would be impracticable with a rigid PCB. The femSense circuit board was assembled with the temperature sensor and a battery using surface-mount technology (SMT). AT&S not only developed the circuit board, they also assembled it with components utilising corresponding capacities and technologies in their Korean factory. The Korean plant particularly specializes in flexible PCB solutions for the medical sector.

Close cooperation with SteadySense is just one example of how AT&S contributes its extensive expertise beyond the PCB and into system design, while being closely involved with partners or customers in product development from an early stage. AT&S particularly supports young, innovative startups and is the ideal development partner to realize new design ideas even for low volume applications. In addition, proximity to the technology cluster around Graz is an important factor for innovations.