ABSTRACT

Electronic textiles (e-textiles) are fabrics where computing elements, sensors, actuators, and networks are an intrinsic part of the cloth. E-textiles are an enabling technology for wearable computers (Starner 2001a,b) that look like normal clothing and for intelligent room furnishings in a pervasive computing environment. In this chapter, we make the case that e-textiles occupy a unique corner of the distributed, embedded computing design space, and therefore require a hardware and software architecture that is tailored to this space. While previously reported research in e-textiles has primarily examined individual applications, the technology itself supports, and to a large extent requires, a computing architecture that simultaneously supports multiple applications and heterogeneous sensors and computing elements. For example, users should not be expected to choose between garments that support MP3 capability (Jung, Lauterbach, and Weber 2002), heart monitoring (Paradiso et al. 2003), and gait analysis (Edmison et al. 2003); all three capabilities and more

6.1 Introduction ................................................................................................... 135 6.2 Properties of E-Textiles ................................................................................. 137

6.2.1 Wearability ........................................................................................ 137 6.2.2 Reliability ......................................................................................... 138 6.2.3 Adaptive Functionality ...................................................................... 139

6.3 A Hardware Architecture for Electronic Textiles .......................................... 140 6.3.1 On-Fabric Digital Communication Network .................................... 140 6.3.2 Two-Tier Processing Architecture .................................................... 143

6.4 The Software Architecture ............................................................................ 145 6.4.1 E-Textile Software Services .............................................................. 146 6.4.2 Overview of the Publish-Subscribe Architecture ............................. 147

6.5 Concluding Remarks ..................................................................................... 149 Acknowledgments .................................................................................................. 150 References .............................................................................................................. 150

should be simultaneously and reliably available to the user. To draw an analogy with desktop computing, the current state of the art of e-textiles is equivalent to requiring a different desktop computer for each application that the user would like to run: one computer for word processing, one computer for using a spreadsheet, and a third for browsing the Web. Instead, a single e-textile fabric should support multiple applications running simultaneously, each with a range of sensing and computation requirements.