This thesis reports the results of a study of problems associated with fabric sewing, such as seam pucker and sewing damage, in commercial garment manufacture. Part 1 continues previous work by the author on seam pucker in structurally jammed fabrics; in particular it has been shown that initial Young's modulus of a fabric is a measure of the ability of the fabric to accommodate compressive forces during sewing. This result provides an additional means of predicting the tendency of a fabric to exhibit seam pucker. The static mechanism of seam pucker proposed previously, based upon the relative magnitudes of bending stiffness of thread and fabric, has been revised by establishing that sewing machine dynamics and pucker are closely related. It has been shown that presser foot bouncing in particular induces pucker and that the sewing thread needs to be positively controlled during stitch formation. These results were verified by simple experimental methods, suggesting that modifications to the sewing machine are needed. Such modifications are beyond the scope of this work. Following the earlier static mechanism of seam pucker, it has been shown that seam pucker in fabrics is reduced significantly when the bending stiffness and extensibility of the sewing thread is reduced. In addition seam pucker can be eliminated by improving fabric stiffness locally along the seam area, by incorporating a stiffening material in the seam; this is based upon the technique of pucker elimination found in the author's previous work. In this study this technique is implemented with considerable success in other types of seams and commercially available stiffening materials have been selected. Part 2 investigates sewing damage to fabrics due to sewing needle penetration. Preliminary studies suggested the need for a reliable testing facility. This was made by instrumenting an industrial overlock sewing machine. The instrumentation was based on measuring the force which is exerted by the sewing needle when penetrating the fabric. The testing facility consists of the sewing machine with a strain gauged sewing needle and plate, and a shaft encoder for stitch marking, which with proper signal amplification and conditioning could be fed to a transient recorder and osciloscope for signal capturing and plotting. Investigations with fabrics revealed that the magnitude of the peak force of each stitch cycle can be related to the degree of sewing damage in the fabric. Based on these results the most important variables in sewing damage were fabric softening and its effective application during finishing, and sewing needle size. Studies of sewing damage under dynamic conditions have shown that sewing damage is a frictional problem between yarns in the fabric and between yarns and the metal of the sewing needle, foot, plate and feed dog. The size of the needle plate of the sewing machine seems to affect the degree of damage and fabric "flagging" during sewing damage has been experienced. Finally in the latter section of this study a prototype routine sewing damage tester has been developed and each stage of its development is described. This tester is based on an instrumented overlock sewing machine, which is interfaced with an IBM PC for computerised data capture and analysis in real time.

A mechanical method for reducing the spirality of single jersey tubular weft knitted fabrics is described. Initial attempts, using a false twisting device, did not prove successful. A later, successful method was developed, based on changes in yarn torque produced by a steaming and untwisting method. The new method is shown to be very effective in reducing spirality. Microscopic examination of changes in yarn structure, including characteristics of fibre migration have also been carried out.

The previous work on measurement of weaving resistance, i. e. the force needed to beat the weft into a fabric, is reviewed and the refinement of one method is described. That method is then used in a comprehensive set of experiments in which the tension applied to the warp and the balance and timing of the shed are all varied. A consistent pattern of influence of the settings on weaving resistance is established and illustrated in graphs. The main experiments relate to plain weave, but the weaving of 2/2 twill is covered in a rather less comprehensive way. The optimum settings are found to be different for the two weaves, and these differences are explained in terms of previous theoretical work. It is shown that the adoption of optimum settings permits the weaving of denser fabrics.

The financial burden on global healthcare systems has reached unprecedented levels and as a result, attention has been shifting from the traditional approach of disease management and treatment towards prevention (Swan, 2012). Wearable devices for Preventative Health have become a focus for innovation across academia and industry, thus this thesis explores the design of wearable biochemical and environmental sensors, which can provide users with an early warning, detection and monitoring system that could integrate easily into their existing lives. The research aims to generate new practical knowledge for the design and development of wearable sensors and, motivated by the identification of compelling design opportunities, merges three strands of enquiry. The research methodology supports this investigation into material, form and function through the use of key practice-based methods, which include Participatory Action Research (active immersion and participation in a particular community and user workshops) and the generation and evaluation of a diverse range of artefacts. Based on the user-centred investigation of the use case for biochemical and environmental sensing, the final collection of artefacts demonstrates a diverse range of concepts, which present biodegradable and recyclable nonwoven material substrates for the use in non-integrated sensors. These sensors can be skin-worn, body-worn or clothing-attached for in-situ detection and monitoring of both internal (from the wearer) and external (from the environment) stimuli. The research proposes that in order to engage a broad section of the population in a preventative lifestyle to significantly reduce the pressure on global healthcare systems, wearable sensors need to be designed so they can appeal to as many users as possible and integrate easily into their existing lifestyles, routines and outfits. The thesis argues that this objective could be achieved through the design and development of end-of-life considered and cost-effective substrate materials, non-integrated wearable form factors and meticulous consideration of a divergent range of user needs and preferences, during the early stages of design practice.

No description available.

Friction spinning is a relative newcomer to textile technology. It has generated great interest because of its potential for wide application of certain problems regarding the quality of yarn produced at high output rates can be solved. General acceptance of the process is hindered by uncertainty as to its capability of producing yarns of sufficient strength at speeds greater than 300 m/min. (NB: as a guide, maximum output rates of competitive technologies are no more than 150 m/min.) Friction spinning appears to have no intrinsic self-limit to its maximum output rate, unlike ring and rotor spinning which are limited by centrifugal effects leading to excessive yarn breakages. The process will therefore provide something of a quantum leap in output if acceptable yarn quality is achieved.

Solar Textiles came out of the idea that everyone has windows in their homes which need to be shaded. The question was simple, why are we not utilizing the sun’s rays which are hitting the shades throughout the day. The project explored the idea of creating solar curtains which would collect the sun’s energy and put it back into the curtain itself. Solar power, solar sensing, fabrics, shapes and movement is what this thesis is intending to explore. How to bring all of these aspects into a simple curtain that could be put into any household;making the world a more beautiful and ecologically friendly place.

Desde el comienzo de la humanidad, el hombre ha utilizado colorantes. Hasta mediados del siglo XIX, todos los colorantes empleados eran de origen natural, tanto orgánicos como inorgánicos. La fabricación de colorantes sintéticos se inició en 1856. Ya a comienzos del siglo XX, los colorantes sinté-ticos suplantaron casi por completo a los colorantes naturales. Sobre la base de la estructura química o del cromóforo, se pueden discernir 20-30 grupos diferentes de colorantes. Los colorantes azo (monoazo, disazo, triazo, poliazo), antraqui-nona, ftalocianina y triarilmetano son los grupos cuantitativa-mente más importantes. La principal vía por la que los colorantes se incorporan al ambiente es a través de las aguas residuales. Muchos colorantes son visibles en agua a concen-traciones tan bajas como 1 mg/L. Los efluentes textiles típica-mente presentan un contenido de colorante en el intervalo 10-200 mg/L y son altamente coloreados. La liberación de estos colorantes supone un peligro ecotóxico. Es así que la descar-ga de aguas residuales coloreadas provenientes de diversos sectores industriales es actualmente un grave problema de la gestión ambiental. Se pueden emplear varios pre-tratamientos físicos, químicos y biológicos, previos al tratamiento principal y a las técnicas de post-tratamiento para eliminar el color de las aguas residuales que contienen colorantes. El objetivo de esta Tesis fue estudiar la eliminación de tres colorantes comerciales: alizarina (colorante antraquinona), azul negro de eriocromo R (colorante azo), y fluoresceína (colorante aril-metano). Los mismos fueron elegidos porque pertenecen a las tres clases de colorantes que representan el mayor porcen-taje de color en un efluente textil real. En primer lugar se detallan las propiedades y la caracterización de los óxidos de hierro utilizados como adsorbentes: goetita, Co-goetita y magnetita, así como también de los tres colorantes seleccio-nados. Luego, se presentan los resultados obtenidos en el estudio de adsorción de los tres colorantes utilizando a los tres óxidos de hierro. Se muestra el estudio de las isotermas de adsorción, el comportamiento de la adsorción en función del pH, las propiedades ácido-base de los sitios superficiales libres y unidos al colorante, y los modelados incluyendo reacciones de complejación superficial aplicando un modelo apropiado de doble capa eléctrica. Los tres óxidos de hierro en la secuencia goetita > Co-goetita > magnetita han demos-trado ser eficientes para la remoción de los tres colorantes estudiados en medio acuoso. Los valores de las constantes de acidez superficial de los óxidos estudiados al igual que los valores de las constantes de desprotonación de los colorantes afectarán en forma conjunta el comportamiento de la adsor-ción con el pH. Puesto que en esta Tesis se utilizó al quitosa-no como soporte para la eliminación de colorantes por catá-lisis enzimática heterogénea, se determinó la capacidad adsorbente del quitosano y se compararon los resultados de adsorción con aquellos obtenidos empleando los adsorbentes goetita y magnetita. A partir de las experiencias cinéticas se pudo concluir que la adsorción de todos los colorantes sobre quitosano es rápida y comparable a la de los óxidos de hierro. El quitosano es un adsorbente excelente (mejor que los óxidos de hierro) para alizarina y azul negro de eriocromo R. En el caso de la fluoresceína, la goetita a pH 5 y 9 fue más eficiente como adsorbente que el quitosano. Se emplearon métodos de mecánica molecular para estudiar las interaccio-nes estéricas entre los colorantes y las superficies de los óxidos. Además, se obtuvieron los correspondientes espectros por espectroscopia infrarroja por transformada de Fourier (FTIR), y en el caso de la fluoresceína también se utilizó espectroscopia Raman. El modelado con MM2 nos permitió considerar estructuras diferentes que pueden explicar las tendencias encontradas en la adsorción de estos tres coloran-tes sobre los óxidos de hierro estudiados en esta Tesis. Los modelados teóricos y moleculares empleados en esta Tesis concuerdan con nuestros datos de adsorción y con los espectros FTIR obtenidos a diferentes valores de pH. Se presenta un análisis comparativo de las capacidades de la enzima peroxidasa de rábano picante (HRP) y su biomimético hematin, ambos en forma libre, en reacciones específicas para la eliminación de los tres colorantes seleccionados. Las activi-dades de la HRP y del hematin son claramente diferentes. No sólo la eficiencia en la eliminación final de los colorantes es diferente, también existen claras diferencias en las vías de reacción. El hematin demostró ser un biomimético potencial, útil y eficaz de HRP. Finalmente, se muestra el estudio de la inmovilización tanto de HRP como de hematin sobre diferen-tes soportes para ser utilizados en la remoción de los tres colorantes. Se evalúa la actividad catalítica a través de experiencias que surgen de la aplicación de un diseño experi-mental utilizando el programa Statgraphics Centurion XVI, y se establece la estabilidad de los sistemas estudiados mediante ensayos de reuso. Se pudo demostrar que la adsorción simple no resulta un método efectivo para inmovi-lizar HRP al quitosano, mientras que sí se logra inmovilizar a esta enzima en el quitosano a través de la activación con glutaraldehído. Solamente se realizó un diseño factorial para el azul negro de eriocromo R. Las experiencias de reuso mostra-ron que los catalizadores soportados son más estables que los solubles. / Since the beginning of humanity, man has used dyes. Until the midnineteenth century, all dyes were natural, organic and inorganic. The manufacture of synthetic dyes began in 1856. By the early twentieth century, synthetic dyes almost comple-tely supplanted the natural dyes. On the basis of the chemi-cal structure or chromophore, one can discern 20-30 different groups of dyes. Azo dyes (monoazo, disazo, triazo, polyazo), anthraquinone, phthalocyanine and triarylmethane are quanti-tatively the most important groups. The main route by which dyes enter the environment is through wastewater. Many dyes are visible in water at concentrations as low as 1 mg/L. Textile effluents typically have dye content in the range 10-200 mg/L and are highly coloured. The release of these dyes supposed an ecotoxic danger. Thus the discharge of coloured wastewater from various industrial sectors is now a serious problem of environmental management. It can be used various physical, chemical and biological pre-treatments, prior to primary treatment and post-treatment techniques to remove colour from wastewater containing dyes. The goal of this Thesis was to study the elimination of three commercial dyes: alizarin (anthraquinone dye), eriochrome blue black R (azo dye) and fluorescein (aryl-methane dye). They were chosen because they belong to the three kinds of dyes repre-senting the highest percentage of colour in a real textile effluent. First details the properties and characterization of the iron oxides used as adsorbents: goethite, Co-goethite and magnetite, as well as the three selected dyes. Next, we pre-sent the results of the adsorption study of three dyes using the three iron oxides. Shown the study of the adsorption isotherms, the adsorption behaviour as a function of pH, acid-base properties of free surface sites and linked to the dye, and models including surface complexation reactions using an appropriate double layer model. The three iron oxides in the sequence goethite > Co-goethite > magnetite have proved be efficient for the removal of the three dyes studied in aqueous media. The values of the surface acidity constants of the oxides studied as well as the values of the constants of desprotonation of the dyes jointly affect the behaviour of the adsorption with pH. Since in this Thesis chitosan was used as a support for the removal of dyes in heterogeneous enzymatic catalysis, we determined the adsorbent capacity of chitosan and compared the results of adsorption with those obtained using the adsorbents goethite and magnetite. From kinetic experiments it was concluded that the adsorption of all dyes on chitosan is rapid and comparable to that of iron oxides. Chitosan is an excellent adsorbent (rather than iron oxides) for alizarin and eriochrome blue black R. In the case of fluorescein, the goethite at pH 5 and 9 was more efficient as an adsorbent that chitosan. We used molecular mechanics methods to study the steric interactions between the dyes and the surfaces of the oxides. In addition, were obtained the corresponding spectra by Fourier Transform infrared spectros-copy (FTIR), and in the case of fluorescein Raman spectros-copy was also used. The MM2 modelling allowed us to consi-der different structures that can explain the trends found in the adsorption of these three dyes on the iron oxides studied in this Thesis. The theoretical and molecular modelling used in this Thesis is consistent with our adsorption data and FTIR spectra obtained at different pH values. We present a compa-rative analysis of the capabilities of the enzyme horseradish peroxidase (HRP) and its biomimetic hematin, both in free form in specific reactions for the elimination of the three selected dyes. The activities of HRP and hematin are clearly different. Not only the final removal efficiency of the dyes is different, also there are clear differences in reaction pathways. The hematin proved to be a potential HRP biomimetic, useful and effective. Finally, we show the study of both HRP and hematin immobilization on different supports for use in the removal of the three dyes. Catalytic activity is evaluated through experiences that arise from the implementation of an experimental design using the Statgraphics Centurion XVI program, and establishing the stability of the systems studied by tests of reuse. We show that simple adsorption is not an effective method for immobilizing HRP to chitosan, whereas it is achieved to immobilize the enzyme on the chitosan via glutaraldehyde activation. Only a factorial design for eriochrome blue black R was performed. The reuse experien-ces showed that supported catalysts are more stable than soluble ones.

Electronic textiles are a sound platform for wearable computing. Many applications have been devised that use sensors placed on these textiles for fields such as medical monitoring and military use or for display purposes. Most of these applications require that the sensors have known locations for accurate results. Activity recognition is one application that is highly dependent on knowledge of the sensor position. Therefore, this thesis presents the design and implementation of a method whereby the location of the sensors on the electronic textile garments can be automatically identified when the user is performing an appropriate activity. The software design incorporates principle component analysis using singular value decomposition to identify the location of the sensors. This thesis presents a method to overcome the problem of bilateral symmetry through sensor connector design and sensor orientation detection. The scalability of the solution is maintained through the use of culling techniques. This thesis presents a flexible solution that allows for the fine-tuning of the accuracy of the results versus the number of valid queries, depending on the constraints of the application. The resulting algorithm is successfully tested on both motion capture and sensor data from an electronic textile garment. / Master of Science

A wearable device that accurately records a user's daily activities is of substantial value. It can be used to enhance medical monitoring by maintaining a diary that lists what a person was doing and for how long. The design of a wearable system to record context such as activity recognition is influenced by a combination of variables. A flexible yet systematic approach for building a software classification environment according to a set of variables is described. The integral part of the software design is the use of a unique robust classifier that uses principal component analysis (PCA) through singular value decomposition (SVD) to perform real-time activity recognition. The thesis describes the different facets of the SVD-based approach and how the classifier inputs can be modified to better differentiate between activities. This thesis presents the design and implementation of a classification environment used to perform activity detection for a wearable e-textile system. / Master of Science