Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). Includes bibliographical references (p. 169-183). Also available via the World Wide Web.

Decreased fetal movement can indicate uncommon complication of labor; in response, we have developed a non-invasive, wearable monitoring tool to objectively assess fetal movement called the Babykick device. The novelty of this device is that it moves away from a traditional subjective assessment of fetal movement to an objective, quantitative measurement that remains low-cost. The designed tool refrains from utilizing expensive and less available monitoring modalities such as ultrasound imaging, Doppler velocimetry or cardiotocography. Instead, the wearable consists of a piezo-sensitive belt that is wirelessly connected to a phone or tablet. It can be used to record the frequency and amplitude of fetal movements perceived passively and non-invasively on the surface of the abdomen of the pregnant woman for a period of up to one hour while she is supine or seated in a reclined position. The ndings from the Babykick device will be correlated with those from subjective maternal assessment and the observation of the Research Coordinator during the test. This low-cost, non-invasive wearable belt could potentially reduce negative outcomes such as stillbirth, perinatal mortality and neonatal morbidity in low- to middle-income settings and is anticipated to be useful for long-term home monitoring. / Graduate

Ti3C2Tx MXene has gained significant attention for biosensor and supercapacitor applications because of 1) its metallic conductivity, large surface area, and reversible surface redox reactions led to high pseudocapacitance and high-rate performance; 2) the unique 2D morphology and high biocompatibility drive great motivation to design advanced nanohybrid systems with bio-receptors; 3) the high density of surface functional groups offers improved biomolecule loading and flexibility for further functionalization. In this thesis, biosensors and electrochemical energy storage devices based on Ti3C2Tx MXene are proposed. Specifically, Ti3C2Tx nanosheets were uniformly functionalized with aminosilane to provide a covalent binding for the immobilized bio-receptor (anti-CEA) for label-free ultrasensitive detection of cancer biomarker (CEA). [Ru(NH3)6]3+ is discovered as the preferable redox probe for biosensing. The fabricated MXene-based sensor exhibits a more comprehensive linear detection range and high sensitivity. Further, Ti3C2Tx nanosheets were introduced as the transducer, and Ti3C2Tx /Prussian blue (Ti3C2Tx/PB) composite was synthesized for sensitive detection of hydrogen peroxide. Meanwhile, a one-step patterning process for highly conductive nitrogen-doped laser-scribed graphene (N-LSG) has been developed. Working electrodes (Ti3C2Tx/PB/N-LSG) were extended by using different enzymes for corresponding biomarker detection, namely glucose, lactate, and alcohol. The enzyme/Ti3C2Tx/PB/N-LSG electrodes exhibit significantly improved electrocatalytic activity and outperform previously reported on-chip graphene-based biosensors. Further, a stretchable, wearable, and multifunctional Ti3C2Tx-based biosensor were designed for durable and sensitive detection of biomarkers in sweat. A unique modular design enabled a simple exchange of the specific sensing electrode to target the desired analytes, while an implemented three-phase interface design for the constant supply of oxygen led to superior sensor performance and stability. As expected, during in-vitro perspiration monitoring of human subjects, the physiochemistry signals (glucose and lactate level) could be measured simultaneously with high sensitivity and good repeatability, outperforming traditional reported graphene/PB- and CNTs/PB-based biosensors. Finally, we developed an in-plane hybrid microsupercapacitor, employing battery-type CuFe-Prussian blue analog (CuFe-PBA) as the positive electrode and pseudocapacitive Ti3C2Tx as the negative electrode. Due to the excellent match of the two types of high-rate performance materials in proton-based electrolyte, the designed on-chip device achieved excellent electrochemical performance.

Thin film heaters, corrosion-resistance electrode, thin film inductors / Stretchable electronics are soft and light weight. Compared with conventional wafer-based electronics, which are rigid and planar, stretchable electronics can conform to curved surfaces and movable parts. The unique properties of stretchable electronics enable their integration with the human body, and open the door for ever more compelling applications, such as advanced surgical tools, wearable monitoring electronics, implantable prosthesis, and many others. However, the development of stretchable electronics is still at an early stage since their mechanical robustness and electrical performance are still far from satisfying. In this work, I have developed a method to fabricate thin film stretchable devices by solvent-assisted transfer of wrinkled thin films from rigid polystyrene (PS) substrates to elastomeric polydimethylsiloxane (PDMS) substrates. Using this approach, structured thin films containing multiple materials and hybrid structures could be lifted off simultaneously, facilitating the fabrication of stretchable thin film devices. With this approach, I have built corrosion-resistant stretchable electrodes, stretchable thin film heaters, and stretchable thin film inductors. These applications demonstrate the simplicity and effectiveness of this stretchable electronics fabrication strategy. Finally, I made the first step towards fabricating dye-sensitized solar cells (DSSCs) with room temperature processes, including the preparation of mesoporous TiO2 layers through mechanical compression and the integration of an interdigitated electrode that was fabricated solely by bench-top patterning, alignment, and sputtering deposition. These steps lay the foundation for the future development of stretchable DSSC. I anticipate that the fabricated stretchable thin films electronic components will contribute to the advancement of wearable and implantable electronics. / Thesis / Doctor of Philosophy (PhD) / Electronics that can be deformed and conform to the irregular surfaces are attractive because they can be better integrated with the human body. For example, they could improve disease diagnostics and therapeutic treatments by providing wearable continuous monitoring devices and more advanced surgical tools. In this work, I created wrinkled thin films that could be affixed onto an elastic substrate and stretched. The principle of operation of these wrinkled devices mimics the way that the wrinkled skin on our knuckles and elbows allows us to bend our fingers and elbows. This approach makes wrinkled thin films stretchable and could lead to robust electronic devices. I have showcased this approach building a corrosion-resistant stretchable electrode, thin films heaters that can closely conform to joints, and a spiral-shaped inductor that could be used to wirelessly transfer data or power wearable devices. I believe that this work will contribute to the development of electronics that can be worn or implanted in the human body.

Intra-articular corticosteroid knee injections (ICIs) were used as a tool to determine the sensitivity of wearable inertial sensors and machine learning algorithms in identifying meaningful changes in gait patterns amidst day-to-day fluctuations in out-of-laboratory gait. Specifically, three overarching aims were proposed; I) Determine if three gait trials could define an everyday typical gait pattern, II) investigate if post-injection atypical strides are significantly different from pre-injection atypical strides and III) explore the relationship between changes in pain and atypical strides. Nine knee OA patients (7M/2F) were recruited from St. Joseph’s Healthcare Hamilton. Participants completed a total of four walking trials prior to the ICI and three following. Participants were fitted with two wearable sensors on each shank just below the knee, and one sensor on the lower back during every trial. Data from these sensors were processed to train and test a one-class support vector machine (OCSVM). Individual gait models were created based on three out of the four pre-injection trials. Each trained model was tested on a withheld pre-injection trial and three post-injection trials to determine the number of typical and atypical gait cycles. Self-reported pain was analyzed throughout the study and compared to the percent of atypical strides seen during each walk. It was found that three gait trials could not define a typical gait model and that post-injection atypical strides were not significantly different from with-held pre-injection atypical strides. Finally, large variations and fluctuations in self-reported pain were observed on a week-to-week basis, which were not significantly correlated to atypical strides observed. This study was the first to investigate the sensitivity of wearable inertial sensors and machine learning algorithms to detect changes in real-world gait patterns and provides foundational work for using wearable sensors to monitor and triage knee OA patients. / Thesis / Master of Science (MSc)

Recent advances in technology are reshaping and enhancing the role of the industrial designer. While industrial designers are already trained to be experts in process and possess a wide range of skills, there must be a higher level of fusion between design, science, and technology than ever before. This paradigm presents an opportunity in the emerging field of wearable technology; industrial design, engineering and computer science would be an optimal collaboration for the inevitable increase in mixes of disciplines to address all aspects of a product and its development. By investigating products from companies such as Nike and Adidas, and also by exploring themes of personal augmentation in science fiction, this thesis will explore the conceptualization of a soft, wearable garment system for runners that utilizes developing advancements in technology, apparel and graphical user interface. / Master of Science

No description available.

This study proposed a new topic in exploring what factors cause most Chinese customers not continue to use their healthcare wearables after purchasing. Based on the framework of “the self-regulation of attitudes, intentions, and behavior” (Bagozzi, 1992), which is used to determine what factors impact satisfaction and how satisfaction can in turn impact stickiness, this study developed a new research model and proposed seven hypotheses. And based on the theories, firstly, this study used interview technique to understand what practical factors people think about would affect consumers’ satisfaction and stickiness towards healthcare wearables in China. Secondly, combined theories with all the hypotheses and the interview results, this study applied survey method to collect empirical data. As all the constructs were validated with exploratory factor analysis and reliability analysis, then the model was tested with linear multiple regression. The findings showed that the proposed research model fits in testing in this study, as three factors (value, quality and trust) have significant effects on Chinese consumers' satisfaction and stickiness towards healthcare wearables consumption. This study suggested that healthcare wearable companies need to put more emphasis on maintaining and increasing consumers’ trust, should continually improve consumers’ satisfaction, and should emphasize more on how to improve consumers’ attitudes of value and trust instead of putting more efforts on quality. These study results can help healthcare wearables companies make correct marketing strategies by putting efforts and resources on more valuable aspects, meanwhile, can help Chinese people to really improve health by using healthcare wearables.

To investigate the integration of a textile antenna into a woven substrate at the point of production. The antenna was to have the characteristics of a conventional fabric interms of the handle and drape.

This thesis explores aesthetization in general and fashion in particular in digital technology design and how we can design digital technology to account for the extended influences of fashion. The thesis applies a combination of methods to explore the new design space at the intersection of fashion and technology. First, it contributes to theoretical understandings of aesthetization and fashion institutionalization that influence digital technology design. We show that there is an unstable aesthetization in mobile design and the increased aesthetization is closely related to the fashion industry. Fashion emerged through shared institutional activities, which are usually in the form of action nets in the design of digital devices. “Tech Fashion” is proposed to interpret such dynamic action nets of institutional arrangements that make digital technology fashionable and desirable. Second, through associative design research, we have designed and developed two prototypes that account for institutionalized fashion values, such as the concept “outfit-centric accessory.” We call for a more extensive collaboration between fashion design and interaction design. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Accepted. Paper 5: Manuscript.</p>