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Lighting Up Your Garments: An Investigation into Methods of Making Fabrics Glow Emma Rowley (N0358635) Smart Design (MSc), School of Architecture Design and the Built Environment, Nottingham Trent University Burton Street, Nottingham, NG1 4BU [email protected] ABSTRACT A growing number of fashion designers and apparel manufacturers are attempting to integrate lighting into their products. Some designers use light to communicate and visualise many different ideas to consumers whereas others are simply trying to keep them safe. There are three commonly used methods employed to light up garments. These are the use of fibre optics, electroluminescent yarns and the use of LEDs with conductive treads. Although many projects have been undertaken by artists and designers using these technologies the author has yet to find a comprehensive resource detailing the advantages of each of these methods and their suitability to various applications. This work sets out to examine the work done to date in this field and detail areas of interest for future development. Author Keywords e-Textiles, lighting, fibre optics, electroluminescence (EL), light emitting diodes (LEDs) INTRODUCTION The idea of wearable electronics is not a new one; the first commercially available range of electronic apparel was released as early as 2000 and was manufactured by Industrial Clothing Design Plus. Ten years later the high street is not full of hats with inbuilt headphones which wirelessly communicate with the wearer‟s mp3 player or cycle safety jackets which light up in the dark. This lack of commercially successful products is primarily due to the fact that most available technologies and materials are simply not suitable for mass produced commercial products [19]. Another reason for the seemingly slow progress in producing products suitable for commercialisation is due to the fact that the field of e-textiles and soft circuits lies directly on the intersection between art and science as fashion meets engineering. Although the power of this medium has been recognised in its potential to address the gender imbalance currently existing in the fields of electrical engineering and programming [9], to date there are very examples of collaborative research involving experts in both fields. This has resulted in many of the projects undertaken in the past taking a fairly limited approach to designing fully integrated circuits into garments, many works attaching off the shelf electrical components to traditional clothing materials resulting in a cloth “bread board” [12]. There have however been some very successful collaborative projects between engineers and fashion designs which have produced interesting, fully functional and aesthetically pleasing outcomes, namely the e-Motion project in 2008 [20]. This paper aims to further build these bridges between the two communities to allow greater understanding between the fields of fashion and engineering. Although the author has no more than an interest in the field of fashion and textiles they aim to highlight several noteworthy projects which use lighting in their design to illustrate to the engineering community the creativity of, and challenges faced by, fashion designers wishing to experiment with this medium. The author will also try to simply explain the technology behind each of the three lighting methods discussed in this paper to allow novices in the field of electronic circuit design to understand the needs and limitations of each of the methods. The lighting methods examined in this paper will be fibre optic fabrics, electroluminescent dyes, wires and panels and light emitting diodes. These methods have been selected as they are the three most commonly used methods for making fabrics light up in both DIY projects and in more professional contexts. Each section will begin with a brief overview of the technology and an explanation of the technical considerations when applying this technology to pieces of fashion. This will be followed by a few recent or current examples of the method being used in the fashion industry and details of how the technology has been integrated into these projects. FIBRE OPTIC FABRICS Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. CHI 2009, April 4–9, 2009, Boston, Massachusetts, USA. Copyright 2009 ACM 978-1-60558-246-7/09/04...$5.00. Fibre optics are long thin strands of very pure glass. Commonly used in telecoms to transmit light signals over very long distances, the fibres consist of a core of glass, about the width of a human hair, which is surrounded in an optic cladding to reflect the light back into the core and all wrapped in a protective plastic coating. Research into using fibre optic textiles dates back to 1996 and a project called “Georgia Tech Wearable Motherboard” (Smart Shirt) which ELECTROLUMINESCENT DYES, WIRES, PRINTS AND PANELS was funded by the US Navy. In 2002 France Telecom announced that a prototype of a flexible screen utilising fibre optic technology had been developed. This innovation allowed for garments to become graphical communication interfaces for the first time [16]. However this technology has since been made generally obsolete by recent developments in organic light emitting diode (OLED) screens. This technology utilises the fact that when electroluminescent substrates, such as phosphors, are exposed to a high frequency electric field they will radiate light. The two most commonly found electroluminescent (EL) products are panels and wire. EL panels take the form of a base, commonly a thin plastic sheet, with fine layers of inks printed over it to form the lamp. First a layer of conductive silver is printed onto the base, followed by two dielectric layers and then the EL layer. The panel then needs to be coated in a further conductive layer; this layer is required to be transparent to allow the light to be transmitted to the viewer. In order for the voltage required to illuminate the panel to be kept at a minimum these layers need to be as thin as possible, current panels use layers of phosphors and dielectrics which are only micrometers thick. EL wires use a similar combination of layers of materials, only the dielectric and EL layers are applied directly onto a copper wire instead of being printed onto plastic coated with silver. Both of these products are flexible yet not soft like a fabric. Luminex fabric, which was named in TIME magazine‟s coolest inventions of 2003 [10], allowed fabric to be given its own luminescence rather than just being reflective or „glow in the dark‟. Indeed the fibres themselves do not emit light, but the way they act as a conduit for the light source built into the fabric gave it a “magical” (Lousmijn Van Den Akker) look. The fabric integrates a luminous fibre into a weave of optical strands to give the fabrics its glow. The power requirements of this luminescent fibre dictate the needs of the fabric. Data found by the author suggest that this fibre requires a 200V supply [16], which can be fed by batteries connected to a transformer. Luminex fabric samples purchased through LumiGram are sold with all these connections already made requiring the user to simply plug in. Although Luminex fabric is washable, the fabric is fairly fragile and care much be taken not to fold the fabric in a way which will cause the glass fibres to snap. This means that the fabric is much more flexible in the direction perpendicular, or at right angles, to the direction in which the fibre optic strands run. There have been some experiments carried out by teams attempting to apply EL lamps directly to fabrics and yarns. This has been made possible by the development of LuxPrint by DuPont which is a solvent based vehicle which can be used as a carrier for electroluminescent phosphor powders [15]. There have been several successful projects which have managed to either silk print this or similar ink onto a woven fabric or apply the ink directly onto yarns which can then be knitted or woven. The main flaws in these methods are getting the ink to form sufficiently thin and even films of each of the required layers on the base material and repeated bending of the fabric or yarn can cause the printed lamp to fracture, potentially causing breaks in the printed circuit. Designers working with Fibre Optics LumiGram There are a number of designers licensed to work with Luminex fabric. One of these companies trades under the name of LumiGram and their fibre optic garments are available to purchase on the internet [3]. LumiGram, based in France, sell a number of off the shelf fashion items, such as various tops, as well as bespoke custom designs for both clothing and interior decoration. It also possible to purchase fabric samples though this online outlet as well as spare or replacement optical modules to allow the user to change the colour of the illuminated garment. EL products require a high frequency alternating current (AC) supply. Glowire runs at 120V AC and needs a frequency of about 2000Hz (2kHz) although the voltage required depends on the length of wire being. The brightness of the wire is also directly dependent on the frequency of the electricity used to run it, the higher the frequency the brighter the wire will glow. However running the wire at a high frequency will reduce its life; a length of Glowire operated at 4kHz will glow with a consistent brightness for about 1600 hours, whereas the same length run at 400Hz will glow for over 5600 hours without a reduction in its intensity [1]. Scarlett Holland – Fibreoptic Handbag Scarlett Holland produced a range of handbags using fibre optic materials in combination with laser cutting and LEDs as part of her masters in Fashion and Technology at Coventry University. The handbags were exhibited at the Made in Future: Made in UK partnering event held in Milan, Italy in December 2009. This event was held to bring research centres in the UK together with commercial enterprises in Italy who may be interested in pursuing their work at a commercial level. Sarah‟s work was exhibited as an example of the cutting edge design and research work being carried out at Coventry University as it combines optical fibres with LEDs as the lining of a bag which utilises digital technology and laser cutting to manufacture the exterior and handles of the pieces. Projects and Designers using this Technology Elise Co – Puddlejumper The puddlejumper coat, from 2001, is a raincoat/cape containing EL panels which glow in response to rain. Water sensors are embroidered onto the hood and shoulders of the jacket and allow the electroluminescent panels in the garment to illuminate based on the pattern of the rain. The EL panels are constructed through a silkscreen printing 2 process onto a suitable fabric substrate and then attached to the rain coat [11]. This is required because the most current will flow down the branch with least resistance, therefore each current path must provide the same resistance to the current to ensure an even distribution of current across the branches of the circuit and prevent a single LED from being overloaded. Although this method is more difficult to implement than the series arrangement it offers the advantage that if the resistor values are calculated correctly the failure of a single branch of the circuit should have no effect on the remaining branches which each make separate circuits for the current to follow round. Although the parallel method requires a much lower voltage to run multiple LEDs, when compared to a series circuit, it does significantly reduce battery life. Illum Illum is a concept EL cycle jacket produced through a collaborative project between apparel designers, goose, and product designers, PDD. This project attempts to combine fashion and functionality into a safety garment to allow the wearer to stand out on the road, when it matters, and blend into a crowd [4]. The jacket utilises EL inks to create a garment which produces a 360o light source when activated but appears blank when not in use. This item is also selfcharging using printed photovoltaic panels across the shoulders and on the back of the jacket [2]. Projects and Designers Currently using LEDs LIGHT EMITTING DIODES Light emitting diodes (LEDs) are commonly used as indicator lights on many electrical devices. First introduced in the 1960‟s as a low intensity red light, LED technology has progressed significantly over the last 50 years producing LEDs which give out light across the visible spectrum, as well as infrared and ultraviolet wavelengths. Progression in this field has also lead to miniaturisation of the component as well as a marked reduction in cost. Joanna Berzowska Joanne is research director of the design research studio XS Labs based in Canada. Recent works to come out of the studio include the Leeches [7] and Constellation Dresses [6]. Although both these works focus on the human need or requirement for power to fuel our lives [5], they both visualise this energy usage though emitting light. Leeches takes the form of a dress which is constructed in such a way as to form a power-distribution grid for a series of silicone-coated electronic „leeches‟ which contain three red LEDs and can be attached individually to the dress in a variety of positions and configurations. The „leeches‟ are held in place by magnetic snaps which provide not only the mechanical connection between the dress and the electronic capsule but also the electrical conductivity required. LEDs have become popular with designers working in the field of e-textiles and wearable technology because of their low cost and easy availability. LEDs are available from a number of stockists, based in the UK and around the world, mainly through their online catalogues. Technical data sheets for the components are also easily obtained through the internet. LEDs have fairly low power requirements and generally only need to be driven by a few milliamps. This means that generally to stop the LED from being over loaded a resistor is required to be used in series with the component for most applications. “LED calculators” can be used to work out the resistor size required based on the voltage of the power supply, the type of circuit being used and the voltage and current the designer wishes to drive the LED at. Constellations uses chains of square LEDs sewn to the dresses using conductive treads. The dresses are also covered in six pairs of magnetic snaps, these pairs act as switches for the LED circuit and when joined with a pair of snaps from another dress the LEDs light up. Thus the dresses only function as a group or collection to encourage interaction between the wearers through physical contact. Barbara Layne A major drawback to the use of LEDs in wearables is the difficulty attached to joining them up in chains. LEDs can be connected in series however a greater voltage is required to drive the LEDs without reducing the brightness of the lights. Care must be taken to ensure that the LEDs are connected according to the manufactures instructions and the power supply is also the correct way round (this is true for any arrangement of LEDs). It should be noted that resistors can also be used in this circuit to fine tune the voltage fed to the components in the ring, and that the failure of a single component in the ring will cause all the lights in the ring to go out. Barbara is the director of Studio subTela which focuses on the development of intelligent cloth structures. Her work has focused on the development of soft programmable LED matrices, grids or screens. These arrays are woven into textile bases to create pieces which either interact with their environment through passive sensing, of ambient light levels or the proximity of viewers, or can be programmed by the user to display scrolling texts and patterns. Blue Code, an interactive piece from 2008 [18], comprises of two panels. The first panel contains a hand woven display of 384 blue LEDs and the second companion panel has 8 pairs of conductive squares which the viewer can connect together to change or control the pattern scrolling across the display. The piece can be reconfigured in 256 (or 28) different ways, each one revealing a different weave which has been pre-programmed into the memory of a microcontroller. Parallel circuits can also be used with LEDs. Although this method is not generally recommended it does allow for a large number of lights to be driven off a single low voltage power supply. To run LEDs in parallel they must be either of exactly the same specifications or each have their own resistor in series with the LED in the branch of the circuit. 3 e-MOTION at the end of the fabrication process but instead a part of the fabric itself. E-Motion was a one year project which took place in the 2008/09 academic year. The project was co-ordinated by the Fashion and Textile Design Institute at the University of the Arts, in Berlin and was supported by Fraunhofer IZM, Germany and the Institute for Special Textiles and Flexible Materials – TITV Greiz, Germany. The project hoped to foster a good working relationship between fashion designers and technologists to allow for a series of innovative, interactive and elegant designs. The fashion designed and developed attempts to add another layer of communication between the wearer and the world, projecting the user‟s emotions out into the world without the use of words. Several of the projects utilised LEDs to subtly visualise their messages [14, 20]. The e-Motion projects featured in this document used possibly the most high-tech electronics based solution to the problem with the use of SCBs which are laminated onto the inside of the fabric. These purpose printed circuit boards provide a flat base on to which the electronic components are attached by conventional methods either directly onto the board or soldered to copper wires which are in turn attached to the SCB. Although this appears to be the most technically elegant and commercially viable method its applications may be limited as the drape and feel of the fabric is compromised at the place of the lamination as although the circuit board is flexible and stretchy it will stiffen the fabric which it is laminated to. One of these projects, Pneuma by Synne Geirsdatter, uses carbon-filled stretch sensitive yarn sewn into a tight fitting cocktail dress to detect the breathing of the wearer. The signals from the stretch sensor are processed by a controller unit which is placed, along with other electronic components, on a large stretchable circuit board (SCB) laminated onto the inner layer of the dress. The LEDs integrated into the SCB fade in and out in relation to the strength of the in- and ex-haling of the wearer. The Constellation project uses possibly the most widely used technique for joining LEDs and soft circuits to fabrics which is hand embroidery with conductive threads. This method is simple and requires little specialist knowledge or access to expensive equipment so is therefore widely used across the DIY community. There are a number of different conductive threads available on the internet, which are useful for different applications. Copper threads have the advantage that they can be soldered to, although are expensive compared to the nylon based threads now available. Dis.appear, a coat by Theresa Lusser, was inspired by people‟s interaction, or lack of, with the urban landscape at night. The coat features a collection of white LEDs whose brightness is synchronised to the surroundings by two light sensitive sensors placed at the front and back of the coat, allowing the garment to reflect the atmosphere of the streets around it. The electronic components are, like in Pneuma, integrated onto a SCB and laminated into the inlay of the jacket. There are also individuals and studios developing new and novel ways to utilise this technology to light up various garments. Professor Tilak Dias, of the School of Art and Design at Nottingham Trent University has recently developed a method to embed tiny LEDs, about the same size as a grain of sand, into copper treads which can then be sewn, woven or knitted straight into garments. This process, currently at the proof of concept stage, involves soldering the LEDs into the tread using specialist equipment adapted to work with the flexible nature of the copper threads rather than the standard rigid printed circuit boards [13]. If commercialised this method could allow individuals to purchase lengths of this light up tread, like miniaturised fairy lights, to embroider straight into their clothes. LED Joining Techniques Across the projects given above the designers have used a variety of different methods to attach the LEDs used in their projects to the fabric of their concepts. The author believes these designers and their methods represent a good cross section of the most commonly used methods of applying LEDs to e-textiles. The variety of techniques on show reflects the large range of backgrounds, interests and facilities the various designers are working around. CONCLUSION A number of different methods for lighting up garments have been discussed with a basic outline of their energy requirements and other factors which may require the consideration of the designer when beginning a project using one or more of these methods. It is hoped that this paper provides enough information about the various methods to allow the reader to make their selection of lighting method for their future projects more informed and highlights that the selection process of method is more than just a question of aesthetic but also about how will the technology integrate or join with the fabric. Barbara Layne, uses an interesting solution to the problem of how to build stiff metal based components into a soft fabric structure. Her pieces tend to make use of wirewrapping techniques, which originate in jewellery making, to create robust yet flexible chains of LEDs which can be incorporated into the fabric a long side the traditional yarns as it is woven on a loom [8]. The weaving process allows changes the positions of the lengthwise (warp) and crosswise (weft) yarns so the conductive threads can follow the often complex schematic design of the electric circuits. The result is robust electrical circuits which are fully integrated into the cloth before it is cut and used to make garments [17]; the electronics are not an added extra added Although the author has tried their upmost to highlight a broad cross section of the imaginative and innovate projects which have been undertaken by design teams from around 4 the world, this paper only has space to merely scratch the surface of the work being undertaken in this field. Therefore this paper represents a starting point to illustrate the creativity and challenges faced by fashion designers and those working in the field of textile and apparel design to those of a more engineering science background wishing to develop techniques or technologies for use in this field. [7] Berzowska, J. the leeches. 2010, 11/27/2010 ( 2004). [8] Braddock, S. and O'Mahony, M. Techno textiles 2 : revolutionary fabrics for fashion and design. Thames & Hudson, London, 2005. [9] Buechley, L. A Construction Kit for Electronic Textiles. In Anonymous 10th IEEE International Symposium on Wearable Computers. (Montreux, Switzerland, October 1114, 2006). IEEE Computer Society, http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=406 7731, 2006, 83. Above all this paper shows the need for close cooperation and collaborations between experts in these two fields if etextiles are to move past catwalks, student exhibitions and high-tech super soldier prototype and become common place on the high street. [10] Buechner, M. M., Grossman, L. and Hamilton, A. Coolest Inventions: Coolest Inventions 2003. TIME Magazine, (Nov 2003). ACKNOWLEDGMENTS The author wishes to thank Dr. Sarah Kettley for her guidance and direction in both researching and writing this paper as well as other the students and staff on the Smart Design course at Nottingham Trent University (2010). Thanks should also go to Professor Tilak Dias, Nottingham Trent University, for his time and thoughts on electrical active textiles, and Mark Lawrence for his assistance in editing the final draft. [11] Co, E. luminescent. 2010, 11/28/2010 (Jul 28 2001). [12] DeRossi, D. and Carpi, F. e. a. Eletroactive Fabrics and Wearable Man-Machine Interfaces. In Tao, X. ed. Wearable electronics and photonics. Woodhead ;, Cambridge ; Florida, 2003. REFERENCES [13] Dias, T. Research in Electronically Active Textiles (EAT). ( 2010). [1] Anonymous BASIC GLOWIRE INFORMATION 2010, 11/28/2010 (). [14] Dils, C. e. a. Fraunhofer IZM e-Motion. 2010, 11/27/2010 (). [2] Anonymous Goose Design 2010, 11/28/2010 (). [15] DuPont. Technical Data Sheet: DuPont LuxPrint 8155. (Oct 2009). [3] Anonymous LumiGram, Luminous clothes, fiber optic clothes, fiber optic fabric, luminous fabric 2010, 11/27/2010 (). [16] Emirhan, K. Fiber Optics in Textile. In Anonymous 3rd International Symposium of Interactive Media Design. (Istanbul, Turkey, January 5-7, 2005). http://newmedia.yeditepe.edu.tr/pdfs/isimd_05/14.pdf, 2005. [4] Anonymous Work | PDD product and service innovation consultancy 2010, 11/28/2010 (). [17] Layne, B. more Black Wall Hanging. 2010, 11/27/2010 (). [5] Berzowska, J. Constellation Dresses and the Leeches: Questions of Power for Electronic Garments. In Anonymous International Foundation of Fashion Technology Institutes Conference, 2007. (Toronto, Canada, April 27-30, 2007). http://xslabs.net/papers/iffti07-berzowska-LC.pdf, 2007. [18] Layne, B. More Blue Code. 2010, 11/27/2010 (). [19] Tao, X. Introduction. In Tao, X. ed. Wearable electronics and photonics. Woodhead ;, Cambridge ; Florida, 2003. [6] Berzowska, J. constellation dresses. 2010, 11/27/2010 ( 2004). [20] UdK Berlin - Studiengang Industrial Modedesign - E Motion. 2010, 11/27/2010 (). 5 Design.