The history of CORE


The CORE project started in 2014 where we were investigating if we could use an energy transfer sensor to potentially measure core body temperature.

The energy transfer or heat flux sensor from greenTEG is the technical foundation on which the technology of CORE is built. greenTEG, a spin-off from the ETH University in Zurich, had created a new sensing technology back in 2009, based on the findings from several Ph.D. theses.

greenTEG's energy transfer sensors had been primarily used in the laser detection industry and are even being used on the International Space Station (ISS).  A new special version of the sensor was created for the CORE project that allows it to be miniaturized but still extremely accurate.

CORE for core body temperature monitoring


Combining sensing technologies with human physiology and sports science

Applying the theoretical math used in laser detection and other applications is completely different from applying theoretical math to calculate core body temperature. The reason for this can be found in a term called human thermoregulation, a very complex set of processes, which is regulated by the central nervous system and is different for every person. Therefore, a new approach was proposed, and years of clinical trials started, collecting a tremendous amount of data as well as a steep learning curve in terms of human physiology and sports science.

The first difficulty was defining what Core Body Temperature is and how it can be accurately measured. Ear and oral thermometers are not very accurate, so they cannot be used for this purpose. To solve this problem, we used several methods, depending on the study: heart catheter, rectal probes, and e-pills. 

THe gSKIN XU sensor

After several years of data collection, we found clear trends and we could start to make use of them to make accurate readings with CORE.  As the development progressed the accuracy kept increasing and this is what we continue to do today.

To showcase the CORE technology, we wanted to prove that it works well in the most difficult environments - which is during outdoor sports.  For this reason, we started developing CORE, simultaneously creating a new non-invasive body parameter providing valuable insights for training and performance. The result is the device you can use and enjoy today.

The CORE technology can be integrated into other products and wearables from heart rate monitors, medical patches, or even smartwatches.  If you wish to find out more about these options please contact greenTEG to discuss your project.