A counter of number of products on the shelf - Influences on capacitance of interdigitated capacitor with application in intelligent packaging

Abstract

© MIDEM Society flexible substrate, ink-jet printing, intelligent packaging, interdigitated capacitor (IDC), silver ink. This work is partly supported within the project TR32016 and the equipment provided within the FP7 APOSTILLE project, no. 256615, financed by EC. Products availability on the shelf, in the store, is a very important aspect in order to provide consumer satisfaction. Instead of conducting physical store audit, this paper demonstrates a counter of the exact number of the products on the shelf prototype realization. The complete test platform on Plexiglas has been developed. The proposed principle is based on interdigitated capacitor fabricated using ink-jet technology, where one set of silver electrodes is posted on the platform and another set on the boxes (products). When all products are on the test platform (or shelf ) the capacitance has a maximum value. Taking products from the shelf this capacitance decreases and complete hardware solution has been made to transfer measured capacitance into number of products and to show this number on the display and turn on warning messages, if it is necessary. The proposed solution enables early detection of low number of products on the shelf and timely replenishment. This paper studies performance of interdigitated capacitors printed with ink-jet printing technology on flexible substrate. Focus point of research presented in this paper is influences of different factors (number of capacitors connected in parallel, accurate position of electrodes of one capacitor, frequency range, etc.) on the capacitance of the structure. Main results are in the demonstration of capacitance change due to the influence of position between electrodes. Test platform, using this principle, has been made to demonstrate that it can be used as an effective solution for out-of-shelf problem.