NISCAIR Online Periodicals Repository Community: IJFTR Vol.36 [2011]

Development and characterisation of elastomeric tape sensor fabrics for elbow angle measurement

Mon, 28 Nov 2011 22:58:59 GMT

Title: Development and characterisation of elastomeric tape sensor fabrics for elbow angle measurement

Authors: Kannaian, T; Neelaveni, R; Thilagavathi, G

Abstract: This paper deals with the development of electro-active elastomeric fabric sensor using silver coated polyamide yarn at the centre of the tape along with polyester and rubber yarns and its electrical characterisation for the application towards elbow angle measurement. Box and Behnken 3-variable and 3-level experimental design has been used and 15 different samples are produced. The resistance change in the samples caused by linear extension as well as the angular movement of the elbow is measured. The variables for sensor design have been optimized using gauge factor (∆r/∆x) values as dependent variable and the results show that the variables such as number of conductive threads, picks per inch and rubber: polyester thread ratio influence the ∆r/∆x value negatively. Different sensor characteristics have also been analysed. The sample with 4 conductive threads, 20 picks/inch and 1:8 polyester : rubber ratio shows a higher gauge factor of 0.583 and has proportional resistance change with length; this sample is therefore chosen to be good among all the 15 samples developed. It is also observed that this sample with higher sensitivity value can be used to measure elbow joint up to 90⁰ angle.

Page(s): 436-442

Flexible displays for smart clothing: Part II— Electrochromic displays

Mon, 28 Nov 2011 22:58:59 GMT

Title: Flexible displays for smart clothing: Part II— Electrochromic displays

Authors: Meunier, Ludivine; Kelly, Fern M; Cochrane, Cédric; Koncar, Vladan

Abstract: Chromic materials have the ability to change their colour reversibly according to external environmental conditions. They are categorised by the stimulus that triggers the colour change. For example, thermochromic materials can be defined as those in which a colour change is induced by a change in temperature and electrochromic materials are those in which a colour change is induced when an electrical current is applied. Thermochromism is already a well-known application within the textile field, however electrochromism is not as common. In this paper, an overview of the field of electrochromic devices has been presented and the successful development of a first generation flexible textile electrochromic device, achieved by ourselves, is discussed. The flexible electrochromic textile display consists of a novel 4-layer sandwich structure containing a thin spacer fabric with electrochromic compound (Prussian blue), a conductive layer and two electrodes; bottom and upper (transparent). If powered with a low voltage battery, this structure is able to generate a reversible colour change. The switching times have been measured at ~ 5 s and 4.5 V. The colour changes are monitored via CIE L*, a*, b* values.

Page(s): 429-435

Flexible displays for smart clothing: Part I—Overview

Mon, 28 Nov 2011 22:58:59 GMT

Title: Flexible displays for smart clothing: Part I—Overview

Authors: Cochrane, Cédric; Meunier, Ludivine; Kelly, Fern M; Koncar, Vladan

Abstract: This overview describes different technologies and developments over the past few decades that have been used in the production of textile-based flexible displays and screens. The paper covers textile displays based on optical fibres for the use in communicative clothing, fashion or medical applications; large flexible screens based on flexible ribbons and LEDs to make or to create communicative clothing; and low cost, washable ‘textronics’ produced by combining SMD components with textile materials for the production of light-producing multilayered OLED flexible structures. For each technology covered in the review, the examples from the commercial products or from the products under research have been considered to illustrate the concept and its potential applications.

Page(s): 422-428

Comfort properties of pressure garments in extended state

Mon, 28 Nov 2011 22:58:59 GMT

Title: Comfort properties of pressure garments in extended state

Authors: Gupta, D; Chattopadhyay, R; Bera, M

Abstract: Pressure garments are used to exert pressure on human limbs for scar management, venous and lymphatic problems, bone and muscle injury, sportswear, post cosmetic surgery, etc. The amounts of pressure required for each medical condition are different. Pressure garments are produced from knitted elastic fabrics, which on wearing get extended and remain in the extended state, thereby exerting a positive pressure on the body. Since they are worn next to skin and are in intimate contact with the body, their comfort properties are of immense importance. In this paper, an attempt has been made to study the air permeability, water vapour transmission rate and thermal behavior of elastic fabrics in extended condition to simulate the conditions during wear. Results show that the comfort properties change significantly when the fabric is held in an extended state.

Page(s): 415-421