Integration of stretchable and washable electronic modules for smart textile applications

Today electronics in “wearable systems” or “smart textiles” are mainly realised on traditional interconnection substrates, like rigid printed circuit boards or mechanically flexible substrates. The electronic modules are detachable to allow cleaning and washing of the textile. In order to achieve a higher degree of integration and user comfort, a technology for flexible and stretchable electronic circuits was developed. The electronic system is completely embedded in an elastomer material like polydimethylsiloxane (PDMS, silicone), resulting in soft and stretchable electronic modules. The technology uses standard packaged components (ICs) and meander-shaped copper tracks, so that stretchable systems with complex functionality can be achieved. This paper describes how these stretchable modules can be integrated in textiles. Also the influence of the PDMS on the stretchability of the textile has been examined. A basic electronic module with blinking light emitting diodes (LEDs) was designed and produced to illustrate the textile integration and to perform initial washing tests.