Ghent University. Faculty of Engineering and Architecture
Abstract
In recent years, a number of research projects and patents have proposed to apply embroidery of conductive yarn to build electric circuits on textile substrates. To contact electronic modules or components to these circuits, embroidery itself was applied as a contacting method. Thereby, the embroidery needle is stitching through a conductive pad on an electronic substrate and is laying the conductive thread over this pad. The yarn and the pad establish an electrical contact.
However, until today this contacting technology based on embroidery has not been adopted by the industry since reliability issues during stress were reported by different researchers. Yet, neither these failure phenomena were investigated comprehensively, nor was it attempted to understand their cause. This inhibited potential improvements to make these embroidered contacts reliable. Furthermore, the lack of alternative technologies for a reliable and volume producible contacting of embroidered circuits with electronic components or modules kept embroidered circuits from evolving to actual products.
Therefore, this thesis primarily develops an understanding of the contact mechanism underlying embroidered contacts, and develops a theory that explains the failure phenomena. Secondarily the thesis overcomes these reliability issues by improving these contacts and by finding alternatives. The ultimate goal beyond this thesis is a volume producible contacting process. Therefore, this thesis looks mainly at machine embroidered contacts
