Spacesuit Hard Upper Torso Assembly: Development Of Fit Metrics And Customized Design Frameworks

The Hard Upper Torso (HUT) of the spacesuit pressure garment is a central component of a spacesuit, enclosing the upper body and connecting with the shoulder joints, bearings, helmet, hatch, and waist-brief-hip components. The shape and positioning of the HUT and its connected components are critical for ensuring comfort, range of motion, field of view, and minimizing astronaut injury risk.This dissertation aims to build upon previous work on spacesuit sizing and develop new spacesuit fit metrics. Motion-tracking technology has been utilized to define the reach envelope and range of motion for test subjects wearing a HUT. Subjective surveys have also been conducted to evaluate suit mobility, feature alignment, indexing, and discomfort. These tools can be adapted to investigate the effects of HUT sizing, leading to the proposal of new metrics ideal for the fit and mobility of HUT based on these technologies. Additive manufacturing can be employed to create custom spacesuit hardware with minimal additional manufacturing steps. This technique enables efficient testing and benchmarking of a wide variety of HUT prototypes. With the development of fit and performance metrics, it becomes logical to utilize these metrics to design optimally sized HUT geometry. The above goals were pursued through the following activities: 1. Define two separate HUT design frameworks: The first framework will result in an optimally distributed discreet HUT sizing system, while the second will establish a framework for the rapid prediction and design of customized HUTs. 2. Investigate the subjective effect of HUT customization on HUT fitment using a subjective fit survey, demonstrating the benefits of HUT customization. 3. Explore the effect of HUT customization using human in-the-loop testing, including range of motion and reach envelope analyses, highlighting the benefits of HUT customization on suited mobility. 4. Confirm the preliminary feasibility of 3D printed HUTs through stress analysis of virtual HUT prototypes using a range of pressures, shell thicknesses, and candidate materials

Contributions for a new body representation paradigm in pattern design. Generation of basic patterns after the mobile body

Tese apresentada à Faculdade de Arquitectura de Lisboa da Universidade Técnica de Lisboa, para obtenção do grau de Doutor em Design

Development of standardised sizing system and size charts for the production of ready-to-wear clothing for Ghanaian children aged 6-11

Children experience rapid growth rate and often indulge in various physical and motion related activities in education and play spaces. Ill-fitting clothing such as very tight or unproportionally balanced clothes can cause movement restrictions, psychological challenges, and other undesirable health related issues. This makes appropriate clothing sizing crucial to address, as it gives children the right fit that allows room for movement and growth. Effectiveness of fit is based on a sizing system and size charts that have been developed using current and accurate body measurements of a specific population since differences exist among populations. Currently, established size charts and academic publications on sizing systems in Ghana have focused on women. No national database or anthropometric study has been developed exclusively for Ghanaian children. Practitioners either take measurements on ad-hoc basis for made-to-measure outfits; or use adapted versions of the British sizing system for manufacturing ready-to-wear garments such as uniforms. This research has therefore been undertaken to develop a standard clothing sizing system and size charts for Ghanaian children between the (school) ages of 6 and 11. This will sustain the general production of reliably sized garments for Ghanaian children whiles providing appropriate fit. It will further enhance mass production of ready-to-wear garments for the apparel market in Ghana. The study involved both secondary and primary data collection methods. An extensive review of literature was conducted focusing on relevant topics in anthropometry and anthropometric surveys for sizing creation, sizing systems, growth of children and garment fit. A comprehensive set of body measurements including height and weight of the sample population of school children were collected. A critical measurement procedural guide and two instructional videos in English and Twi (dominant Ghanaian language) were developed by the study taking into account efficacy, ethical and sustainable considerations for good practice. These were made available and guided parents/legal guardians and participants in the data collection process during fieldwork. The population consisted of primary school pupils in Ghana. A sample of 776 usable data was used for the analysis. With the IBM SPSS analytics software, appropriate statistical procedures such as means, t-test and analysis of variance tests (ANOVA) were conducted to ascertain the relationships among the variables and to obtain statistical data for the development of the sizing system. Principal component analysis (PCA) and cluster analysis were also used to aid the development of the sizing system. Centred on the PCA technique, three key dimensions (height, chest, and waist girths) were selected based on the factor loading and practicality. The study found and established significant differences between the body measurements of Ghanaian children aged 6-11 along gender lines. Using the cluster analysis technique, the selected dimensions were used to categorize the study sample into homogenous subgroups according to upper and lower body separately for both males and females. Four or five sizes were created for each cluster group, and size charts were established based on percentile values. This study presents theoretical and empirical contributions to the body of knowledge in anthropometrics. It has modelled a guide that demonstrates the capability of remote and safe body measuring practices on children, which is particularly useful, economical, and reliable for clothing related practices that seek to employ consistent traditional manual measuring techniques. The study has created an original up-to-date anthropometric database for Ghanaian children between 6-11 years; and developed a comprehensive sizing system for wider clothing practices. In addition to providing a framework for procedures in creating children’s sizing system and size chart, it establishes new size charts for both males and females aged 6-11, based on the Ghanaian population. These developments stand to increase productivity, consistency, and economic efficiency for the Ghanaian apparel industry. The study makes recommendations for extending this work to other segments of the population

Missed Fit

This thesis examines how the technical fit of a garment can affect an individual’s ability to fit in. It challenges the tool box used by practitioners working with anthropometric data (the surface measurements of the human body) and has produced new methods that are less reliant on published averages. Some of the thesis questions are: how does anthropometric data and the study of human anatomy influence notions of an ideal body? In what ways do anthropometric data and patternmaking principles include or exclude diverse body types? What tools can be developed to assist designing for diverse bodies? It takes a multi-method and multi-theory approach to the research and investigates concepts of fit through phenomenology, semiotics and anatomy. By exploring experimental methods in cut, it challenges the meaning of a key example of conservatism and uniformity in tailoring, the grey flannel suit

Design of human surrogates for the study of biomechanical injury: a review

Human surrogates are representations of living human structures employed to replicate “real-life” injurious scenarios in artificial environments. They are used primarily to evaluate personal protective equipment (PPE) or integrated safety systems (e.g., seat belts) in a wide range of industry sectors (e.g., automotive, military, security service, and sports equipment). Surrogates are commonly considered in five major categories relative to their form and functionality: human volunteers, postmortem human surrogates, animal surrogates, anthropomorphic test devices, and computational models. Each surrogate has its relative merits. Surrogates have been extensively employed in scenarios concerning “life-threatening” impacts (e.g., penetrating bullets or automotive accidents). However, more frequently occurring nonlethal injuries (e.g., fractures, tears, lacerations, contusions) often result in full or partial debilitation in contexts where optimal human performance is crucial (e.g., military, sports). Detailed study of these injuries requires human surrogates with superior biofidelity to those currently available if PPE designs are to improve. The opportunities afforded by new technologies, materials, instrumentation, and processing capabilities should be exploited to develop a new generation of more sophisticated human surrogates. This paper presents a review of the current state of the art in human surrogate construction, highlighting weaknesses and opportunities, to promote research into improved surrogates for PPE development

EXPLORING ILLUSIONS OF HEIGHT IN SUIT DESIGN

Objective: The goal of this research was to explore how the design of clothing, specifically the design of the suit, can create height illusions. Background: Taller people enjoy many advantages, such as increased income and perceived attractiveness. These advantages motivate people to try to appear taller than they actually are, and clothing experts provide advice on how to accomplish this. However, there is little empirical evidence to validate the illusory effects clothing might have on overall height perception. The few studies that have explored illusions of body size created by clothing design have been limited in two important ways – the test stimuli have included unnatural body shapes and have failed to include naturalistic context (i.e., surrounding depth and size cues available in real scenes). Method: In the first phase, participants (nonexperts in clothing design) provided suggestions for how to appear taller by changing clothes. In the second phase, participants 1) viewed photographs of a variety of targets wearing suit designs that are commonly believed to manipulate viewers’ perceptions of height, 2) rated the targets on traits associated with height such as income and attractiveness, and 3) estimated the heights of these individuals. This study focused on the potential effects of suit color, specifically overall lightness (light vs. dark) and monochromaticity (monochromatic vs. lightness blocking). The effects of these designs were tested with and without contextual information by presenting targets within a natural streetscape or on a white background. Results: In the first phase, we found that nonexperts provided similar suggestions as experts in clothing design, including those pertaining to monochromaticity and lightness. In the second phase, we found that estimates were more accurate with more contextual information, and that clothing can impact height estimations, where monochromatic outfits yielded taller height estimates, although other outfit comparisons did not have effects. Outfits overall did not impact ratings such as income and attractiveness, although estimated height did correlate with these same social attributes. In an exploration of the impact of contextual and target-specific cues other than clothing on height estimations, we found that height perception was potentially dependent on a variety of factors such as the target\u27s race, location (indoors vs. outdoors), stance, and the presence of nearby people. Scientific merit: This study increased our understanding of the conditions under which illusions of size in simple geometric stimuli generalize to the manipulation of size perception in real-world scenes. Broader impact: A better understanding of biases in height perception is relevant to domains in which such estimates are used to identify individuals (e.g., criminal justice) as well as domains in which visual characteristics of individuals are associated with errors in judgments of performance-based merit. (e.g., personnel selection and promotion)

Representative testing of personal protection equipment

The purpose of the work reported within this thesis was to design and implement a series of tests which better replicate the impact conditions experienced during a game, and allow for quantitative measurements of performance of various items of personal protection equipment (PPE). The sports of cricket and taekwondo were used as case studies. The aim was to improve on existing testing protocols making them more representative of real life, an approach that has not been previously attempted in the literature and so required design of multiple items of novel equipment. A representative cricket impact test was developed utilizing a ball canon firing a cricket ball mass at an equivalent bowling velocity of 31 m/s (70 mph) and a novel, freely suspended force acquisition system with embedded accelerometers from which the transmitted force values could be derived. Throughout the testing secondary variables of coefficient of restitution (COR), deformation and contact time were measured from high speed video footage to give further insight into the impact mechanics of the three tested leg guards. Contact times were in the range of 3 ms - 4 ms, COR between 0.38 - 0.50 and deformation between 45 mm - 52 mm. These results were compared against other benchmark tests to establish how close the representative test was to an actual human related ball-pad impact and to estimate human tolerance levels to impact. A rig to mimic a human on human kicking impact in taekwondo was designed to measure performance of the piece of body protection equipment used in training and competition, commonly referred to as a hogu. Primarily a mechanical simulator was designed to replicate the speed and mass of a human leg impacting during a roundhouse kick. A force acquisition system was manufactured, capable of integrating with the kicking robot functioning, with a human torso sized and shaped anvil, using a similar accelerometer based system of force measurement as that introduced in the cricket testing. This test was then used to measure performance levels of nine off-the-shelf hogus and protective training pads. Using transmitted peak force and time to peak force (TTPF) as indicators of protection, these values were found to range from between 0.5 kN 7.5 kN and 9 ms - 23 ms across the pads indicating a major difference in the protection provided

An analysis of the anthropometric measurements of the U.S. navy male recruit in order to improve garment and pattern design

The objectives of this study are, first, to improve the clothing and pattern designs of the U.S. Navy male recruits by utilizing anthropometric data, and second, to propose a tariff improvement, if possible. The establishment of a bridge between the anthropometric data and the patternmaker or designer was required. Statistical data of the mean and standard deviation were utilized to identify the range of generic stature sizing for the upper and lower torso garments. These same statistical tools were used to identify the range of generic body type sizes for the full torso garment. The median was utilized for individual garment sizes including the identification of bench marks for pattern and garment design. An improved range of generic sizes was established for stature. The key variable for full torso type garments was identified as vertical trunk circumference and chest circumference. From there a new range of generic size for body type was established. The use of statistical analysis of other body measurements associated with garment design will provide for an improved fit. These same statistical procedures indicate that, in all cases except the new coverall, the tariff required to support 90% of the population can be reduced