While many of the factors influencing strain sensor properties have been explained in literature, other very important parameters that influence actual design performance of sensors remain obscure. This paper investigates the impact of conductive profile and area design including post fabric treatments such as dyeing and washing on sensor performance. 1 × 1 mock rib was the fabric structure of choice, and silver-plaited nylon was the conductive yarn used in knitting all the samples. Six main polygonal shapes including ellipse, diamond shape, corrugated rectangular shape, rectangular horse shoe, rectangular dough roller shape, and plain rectangular shape were designed and knitted. Plain rectangular profile has been found to deliver the best results characterized by noiseless signals, highest gauge factor, and good result repeatability. The analysis of results also reveals a positive linear correlation between conductive path and initial electrical resistance of a sensor. The inverse is true for the relation between the conductive width values and their corresponding initial resistances. Higher conductive widths led to low initial resistance, and values less than 20 Ω for a sensor could lead to inferior sensor sensitivity. High conductive paths produced high initial resistances, and values within the range of 40–120 Ω could deliver higher sensitivity. This study thus concludes that the optimum aspect ratio range for conductive area to deliver satisfactory sensitivity results is approximately between 24:1 and 77:1 cm. Laundry and dyeing have also been found to result in reduced sensor dimensions, resistance, and sensitivity levels.

Recognizing alterations in respiration patterns is an essential early sign not only for disease diagnoses but also for determining psychosomatic condition of the individual. The desire for measuring these parameters outside the hospital setting has led to a great interest in embedding this functionality in everyday wearable materials. This study presents an assessment of respiration patterns using a knitted piezoresistive smart chest band. A total of 20 users—Asians and Africans from 8 countries—were tested 14 times over a 67-day period. Experiments were conducted with users being under several varied test conditions including standing and sitting posture, varying physical activities, and different times in the day. Results show a successful application of the band with result patterns being in congruence with studies conducted using other related respiratory measurement technologies and instruments. Sedentary standing posture presented less signal noise compared to physical activity tests. Individuality and the repeatability of results over time suggest feasibility of the use of breath patterns as a biometric feature. Influences of ethnicity, gender, and body mass index on respiration patterns have also been discussed.

Production parameters have been established to play a fundamental role in dictating the physical characteristics and sensing properties of knitted sensors. This research studied the influence of yarn type and rib fabric structure variation on the physical, tensile and conductive properties and sensitivity performance of knitted underwear strain sensors to be used for breathing mensuration. Four different structures in 1×1, 1×2, 1×3 and 2×2 mock ribs were knitted using covered elastic (CY) and bare strand elastic yarn (BS) combinations. These two parameters proffered unique physical, conductive and tensile characteristics to the samples. Wear and machine tests were conducted to ascertain the sensor’s piezoresistive responses. The machine test showed a higher piezoresistive response, with an average peak value (APV) from 1.70Ω to 0.24Ω, while those for the wear test recorded were around 0.0110Ω to 1.867Ω for all sample categories. However, sensors knitted with covered elastic yarns produced the best breathing test results (APV of 1.089Ω – 1.86Ω) compared to bare strand elastic yarns (APV 0.0027Ω - 0.0790Ω) when used in a wearable environment. Fabric structure variation had influences on both conductive and tensile characteristics; however, the effects on the piezoresistive response were negligible. The influences of the unique characteristics provided by these core parameters on sensor resistance values, piezoresistance, aging, ease of deformation and dimensional stability have also been discussed.

The advent of 3D printing (3DP) has garnered significant interest from both academia and industry due to its potential to revolutionize engineering, manufacturing, and through its utilization of advanced materials. Even though the application of 3D printing in footwear design and manufacture is quite appreciated, academic discourse on the subject relative to footwear design and manufacture is rather scarce compared to other fields such as pharmaceuticals, electronics and food. The purpose of this review is to explore the techniques, the application trends and the impact of 3D printing technology concerning footwear design and manufacture. Using relevant data from many relevant sources, this study uncovered that 3D printing has significantly impacted shoe design and manufacture by enhancing production efficiency, environmental sustainability, material innovation and Inter-Industry Collaborative Projects among others. Most of the major players in the footwear industry such as Nike, Adidas, Reebok and New Balance already have many footwear releases based on 3D printing. Also discussed are some specific areas in which 3D printing is being applied in footwear design and manufacture. These areas include but are not limited to the design of smart shoes, shoe lasts, complex shoe geometries, avant-garde concept shoes and so on. This study is of particular importance to stakeholders in the footwear research and design industry as it provides important information about the current trends as well as the impact of 3D printing technology on the sector.

Purpose: The use of conductive yarns or wires to design and construct fabric-based strain sensors is a research area that is gaining much attention in recent years. This is based on a profound theory that conductive yarns will have a variation in resistance if subjected to tension. What is not clear is to which types of conductive yarns are most suited to delivering the right sensitivity. The purpose of this paper is to look at strain sensors knitted with conductive composite and coated yarns which include core spun, blended, coated and commingled yarns. The conductive components are stainless steel and silver coating respectively with polyester as the nonconductive part. Using Stoll CMS 530 flat knitting machine, five samples each were knitted with the mentioned yarn categories using 1×1 rib structure. Sensitivity tests were carried out on the samples. Piezoresistive response of the samples reveals that yarns with heterogeneous external structures showed both an increase and a decrease in resistance, whereas those with homogenous structures responded linearly to stress. Stainless steel based yarns also had higher piezoresistive range compared to the silver-coated ones. However, comparing all the knitted samples, silver-coated yarn (SCY) proved to be more suitable for strain sensor as its response to tension was unidirectional with an appreciable range of change in resistance.Design/methodology/approach: Conductive composite yarns, namely, core spun yarn (CSY1), core spun yarn (CSY2), silver-coated blended yarn (SCBY), staple fiber blended yarn (SFBY) and commingled yarn (CMY) were sourced based on specifications and used to knit strain sensor samples. Electro-mechanical properties were investigated by stretching on a fabric tensile machine to ascertain their suitability for a textile strain sensor.Findings: In order to generate usable signal for a strain sensor for a conductive yarn, it must have persistent and consistent conductive links, both externally and internally. In the case of composite yarns such as SFBY, SCBY and CMY where there were no consistent alignment and inter-yarn contact, resistance change fluctuated. Among all six different types of yarns used, SCY presented the most suitable result as its response to tension was unidirectional with an appreciable range of change in resistance.Originality/value: This is an original research carried out by the authors who studied the electro-mechanical properties of some composite conductive yarns that have not been studied before in textile strain sensor research. Detailed research methods, results and interpretation of the results have thus been presented.

BACKGROUND: Before the emergence of ready-to-wear (RTW) garments, production of apparels relied on ergonomics considerations through body measurements (anthropometry) of individual users. This is an indication of the inherent nature of ergonomics in apparel fabrication; however active mention of ergonomics related to fashion engineering and design before then was lacking. OBJECTIVE: This article seeks to emphasize the need for an organized framework of knowledge for ergonomics suited to fashion engineering and design education and research. METHODS: Relevant literature have been reviewed and three main knowledge components of ergonomics relevant to fashion engineering and design have been identified and classified based on standard classes of areas within the general field of ergonomics. RESULTS: Areas of ergonomics applications in fashion engineering and design under the headings of consumer product design, i.e. apparel design, workspace or office design, manufacturing process design and man-machine system, have been discussed. CONCLUSION: Comprehensive ergonomics education related to fashion engineering and design consist of the three main knowledge components: (1) the five aspects of ergonomics, (2) anthropometry and biomechanics and (3) the three domains of ergonomics.