Characterization of a radio cap of Valtronic SA Technologies

The precise measurement of insuline volume contained in an insuline pen is crucial for both the patients and the doctors. The development by Valtronic, with the collaboration of the EPFL, of a measurement device with a 10uL resolution, is the focus of this master thesis. This device is called a radio cap. The insuline pen is inserted inside the radio cap. The cap is made so that the system {cap+insuline pen} resembles a waveguide, wherein the external conductor would be the copper envelope and the central conductor would be the insuline solution. The cap would carry a radio transmitter at its tip in order to send a radio wave through the cap, as well as a radio receiver. The transmitter would send a radio wave through that cap, which would be reflected at the end of the insuline column due to a large change of permittivity between insuline and air. The receiver would then register the reflected wave. We get back to the filling level of the ampoule thanks to the phase difference between the incident and the reflected waves. In the following, we model the prototype built by Valtronic, test it’s performances and create a new design wherein said performances are improved.