Computational modelling methods for sports bra–body interactions

2020 ◽  
Vol 32 (6) ◽  
pp. 921-934
Author(s):  
Liang Ruixin ◽  
Joanne Yip ◽  
Winnie Yu ◽  
Lihua Chen ◽  
Newman Lau

PurposeThe breasts are mainly fatty and connective tissues with no muscles that directly support them, so wearing sports bras is one of the most effective means of alleviating the discomfort of breast movement and potential injury during vigorous physical exercise. However, the design and development processes of traditional sports bras are time-consuming and costly. Hence, a novel method of simulating the static contact pressure between a sports bra and women’s body based on the finite element (FE) and artificial neural network (ANN) models is developed in this study to contribute to the design considerations of sports bras.Design/methodology/approachThree-dimensional FE models of a female subject and sports bras with different fabric properties are developed to determine the amount of contact pressure exerted onto the body. The FE results are then verified by measuring the amount of pressure exerted by the sports bra on the skin with pressure sensors. The Taguchi technique is used to effectively reduce the number of trials from 625 to only 25 cases. These 25 results obtained through FE modelling are then used to provide the training set for the ANNs. Finally, a comparison between the FE and ANN results is carried out.FindingsA novel model of the static contact pressure between a sports bra and human subject based on the FE and ANN methods is presented in this paper. The root mean square error values show that there is only a small difference between the FE and ANN results.Originality/valueThe ANN function established in this study can be used to predict the mechanical behaviours of breasts and has a fundamental impact on the computer-aided design of functional garments in general.

2015 ◽  
Vol 35 (3) ◽  
pp. 269-280 ◽  
Author(s):  
Hu Qiao ◽  
Rong Mo ◽  
Ying Xiang

Purpose – The purpose of this paper is to establish an adaptive assembly, to realize the adaptive changing of the models and to improve the flexibility and reliability of assembly change. For a three-dimensional (3D) computer-aided design (CAD) assembly in a changing process, there are two practical problems. One is delivering parameters’ information not smoothly. The other one is to easily destroy an assembly structure. Design/methodology/approach – The paper establishes associated parameters design structure matrix of related parts, and predicts possible propagation paths of the parameters. Based on the predicted path, structured storage is made for the affected parameters, tolerance range and the calculation relations. The study combines structured path information and all constrained assemblies to build the adaptive assembly, proposes an adaptive change algorithm for assembly changing and discusses the extendibility of the adaptive assembly. Findings – The approach would improve the flexibility and reliability of assembly change and be applied to different CAD platform. Practical implications – The examples illustrate the construction and adaptive behavior of the assembly and verify the feasibility and reasonability of the adaptive assembly in practical application. Originality/value – The adaptive assembly model proposed in the paper is an original method to assembly change. And compared with other methods, good results have been obtained.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Wiktoria Maria Wojnarowska ◽  
Jakub Najowicz ◽  
Tomasz Piecuch ◽  
Michał Sochacki ◽  
Dawid Pijanka ◽  
...  

Purpose Chicken orthoses that cover the ankle joint area are not commercially available. Therefore, the main purpose of this study is to fabricate a customised temporary Ankle–Foot Orthosis (AFO) for a chicken with a twisted ankle using computer-aided design (CAD) and three-dimensional (3D) printing. The secondary objective of the paper is to present the specific application of Additive Manufacturing (AM) in veterinary medicine. Design/methodology/approach The design process was based on multiple sketches, photos and measurements that were provided by the owner of the animal. The 3D model of the orthosis was made with Autodesk Fusion 360, while the prototype was fabricated using fused deposition modelling (FDM). Evaluation of the AFO was performed using the finite element method. Findings The work resulted in a functional 3D printed AFO for chicken. It was found that the orthosis made with AM provides satisfactory stiffen and a good fit. It was concluded that AM is suitable for custom bird AFO fabrication and, in some respects, is superior to traditional manufacturing methods. It was also concluded that the presented procedure can be applied in other veterinary cases and to other animal species and other parts of their body. AM provides veterinary with a powerful tool for the production of well-fitted and durable orthoses for animals. Research limitations/implications The study does not include the chicken's opinion on the comfort or fit of the manufactured AFO due to communication issues. Evaluation of the final prototype was done by the researchers and the animal owner. Originality/value No evidence was found in the literature on the use of AM for chicken orthosis, so this study is the first to describe such an application of AM. In addition, the study demonstrates the value of AM in veterinary medicine, especially in the production of devices such as orthoses.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ran-i Eom ◽  
Yejin Lee

PurposeThe use of shoulder protectors is strongly recommended when carrying objects on the shoulder to ensure the health and safety of workers. Thus, this study aimed to develop and verify an ergonomic shoulder protector that considers human body shape and carrying posture from an ergonomic perspective. Ultimately, this study will present a shoulder protector with enhanced fit and safety for carrying workers at construction sites.Design/methodology/approachThe shoulder protector was designed and printed using three-dimensional printing technology with variable side neck points and shoulder point heights to reflect the human body's shoulder line shape and to position the carried object stably on the shoulder. The developed shoulder protectors were evaluated in terms of their fit according to the work posture of the carrier, adherence upon motion and durability through structural analysis.FindingsThe design of the shoulder protector for carrying workers followed the shoulder line. It is best placed above the side neck point by 1.0 cm and above the shoulder point by 2.0 cm. Its length is slightly shorter than the human shoulder for superior fit and safety.Originality/valueThe final shoulder protector (FSP) for carrying workers reflects the body curvature while enhancing fit and safety by considering activity and protective factors. As functional studies and evaluations on the need for protectors are scarce, this study provides fundamental data in the evaluation of protective gears.


2020 ◽  
Vol 32 (5) ◽  
pp. 691-705
Author(s):  
Nazanin Ansari ◽  
Sybille Krzywinski

PurposeThis paper aims to introduce a process chain spanning from scanned data to computer-aided engineering and further required simulations up to the subsequent production. This approach has the potential to reduce production costs and accelerate the procedure.Design/methodology/approachA parametric computer-aided design (CAD) model of the flyer wearing a wingsuit is created enabling easy changes in its posture and the wingsuit geometry. The objective is to track the influence of geometry changes in a timely manner for following simulation scenarios.FindingsAt the final stage, the two-dimensional (2D) pattern cuts were derived from the developed three-dimensional (3D) wingsuit, and the results were compared with the conventional ones used in the first stages of the wingsuit development.Originality/valueProposing a virtual development process chain is challenging; apart from the fact that the CAD construction of a wingsuit flyer – in itself posing a complicated task – is required at a very early stage of the procedure.


2014 ◽  
Vol 41 (10) ◽  
pp. 869-877 ◽  
Author(s):  
Gabriel B. Dadi ◽  
Timothy R.B. Taylor ◽  
Paul M. Goodrum ◽  
William F. Maloney

Engineering information delivery can be a source of inefficient communication of design, leading to construction rework and lower worker morale. Due to errors, omissions, and misinterpretations, there remains a great opportunity to improve the traditional documentation of engineering information that craft professionals use to complete their work. Historically, physical three dimensional (3D) models built by hand provided 3D physical representations of the project to assist in sequencing, visualization, and planning of critical construction activities. This practice has greatly diminished since the adoption of 3D computer-aided design (CAD) and building information modeling technologies. Recently, additive manufacturing (a.k.a. 3D printing) technologies have allowed for three dimensional printing of 3D CAD models. A cognitive experiment was established to measure the effectiveness of 2D drawings, a 3D computer model, and a 3D printed model in delivering engineering information to an end-user are scientifically measured. The 3D printed model outperformed the 2D drawings and 3D computer interface in productivity measures. This paper’s primary contribution to the body of knowledge is identification of how different mediums of engineering information influence the performance of a simple task execution.


Author(s):  
AN Nithyaa ◽  
S Poonguzhali ◽  
N Vigneshwari

Hemiplegia is a type of paralysis that affects one side of the body due to stroke, characterizing severe weakness or rigid movement. Many people of different age groups are affected by this condition which cannot be completely cured but can be minimized through proper physiotherapy. A continuous and repeated exercise has to be given to the hemiplegic subjects to regain their motor function. To serve this purpose, a three-dimensional model of wheelchair contrived with lower limb exoskeleton is designed and motion analysis is done using SolidWorks. This virtual model of the object is created with the assistance of computer-aided design software. Professionals can be able to do the experiment on what-if scenarios with their three-dimensional designs, which helps to validate their devices and identify any snags with design quality. The pattern of behaviour of lower limb exoskeleton is predicted using SimMechanics in MATLAB.


2020 ◽  
Vol 26 (10) ◽  
pp. 1789-1795
Author(s):  
Mattia Mele ◽  
Giampaolo Campana ◽  
Gregorio Pisaneschi ◽  
Gian Luca Monti

Purpose Multi jet fusion is an industrial additive manufacturing technology characterised by high building speed and considerable properties of the parts. The cooling phase represents a crucial step to determine productivity, since it can take up to 4.5 times the building time. The purpose of this paper is to investigate into effects of cooling rate on parts manufactured by multi jet fusion. Crystallinity, density, distortions and mechanical properties of specimens produced through an HP multi jet fusion 4200 are examined. Design/methodology/approach An experimental activity is carried out on specimens cooled down at three different rates. Properties of the parts are analysed by means of differential scanning calorimetry, optical microscopy, three-dimensional scanning and tensile testing. Originality/value The present work makes a contribution to the body of knowledge providing correlations between the cooling phase of multi jet fusion and part properties. These results can be used to choose the right balance between production time and product quality.


2017 ◽  
Vol 23 (6) ◽  
pp. 1020-1031 ◽  
Author(s):  
Miguel Fernandez-Vicente ◽  
Ana Escario Chust ◽  
Andres Conejero

Purpose The purpose of this paper is to describe a novel design workflow for the digital fabrication of custom-made orthoses (CMIO). It is intended to provide an easier process for clinical practitioners and orthotic technicians alike. It further functions to reduce the dependency of the operators’ abilities and skills. Design/methodology/approach The technical assessment covers low-cost three-dimensional (3D) scanning, free computer-aided design (CAD) software, and desktop 3D printing and acetone vapour finishing. To analyse its viability, a cost comparison was carried out between the proposed workflow and the traditional CMIO manufacture method. Findings The results show that the proposed workflow is a technically feasible and cost-effective solution to improve upon the traditional process of design and manufacture of custom-made static trapeziometacarpal (TMC) orthoses. Further studies are needed for ensuring a clinically feasible approach and for estimating the efficacy of the method for the recovery process in patients. Social implications The feasibility of the process increases the impact of the study, as the great accessibility to this type of 3D printers makes the digital fabrication method easier to be adopted by operators. Originality/value Although some research has been conducted on digital fabrication of CMIO, few studies have investigated the use of desktop 3D printing in any systematic way. This study provides a first step in the exploration of a new design workflow using low-cost digital fabrication tools combined with non-manual finishing.


2019 ◽  
Vol 25 (5) ◽  
pp. 857-863
Author(s):  
Fusong Yuan ◽  
Yao Sun ◽  
Lei Zhang ◽  
Yuchun Sun

Purpose The purpose of this paper is to establish a chair-side design and production method for a tooth-supported fixed implant guide and to evaluate its accuracy. Design/methodology/approach Three-dimensional (3D) data of the alveolar ridge, adjacent teeth and antagonistic teeth were acquired from models of the edentulous area of 30 patients. The implant guides were then constructed using self-developed computer-aided design software and chair-side fused deposition modelling 3D-printing and positioned on a dental model. A model scanner was used to acquire 3D data of the positioned implant guides, and the overall error was then evaluated. Findings The overall error was 0.599 ± 0.146 mm (n = 30). One-way ANOVA revealed no statistical differences among the 30 implant guides. The gap between the occlusal surface of the teeth covering and the tissue surface of the implant guide was measured. The maximum gap after positioning of the implant guide was 0.341 mm (mean, 0.179 ± 0.019 mm). The implanted axes of the printed implant guide and designed guide were compared in terms of overall, lateral and angular error, which were 0.104 ± 0.004 mm, 0.097 ± 0.003 mm, and 2.053° ± 0.017°, respectively. Originality/value The results of this study demonstrated that the accuracy of a new chair-side tooth-supported fixed implant guide can satisfy clinical requirements.


2020 ◽  
Vol 32 (5) ◽  
pp. 743-759
Author(s):  
Hyunjung Han ◽  
Hyunsook Han ◽  
Taehoon Kim

PurposeThe purpose of this paper is to propose the swimsuit patternmaking method suitable for the body shapes of middle-aged women and to propose the swimsuit pattern development procedures that enable automated swimsuit patternmaking.Design/methodology/approachTo propose the patternmaking method of the swimsuit, which is suitable for the body shape of middle-aged women, the swimsuit patterns were developed in three stages in this study. The measurements of the middle-aged woman body model were compared with the size of the developed pattern in each stage, and the optimal stretch rate of the fabric was defined. In total, 22 items were used for size analysis of developed patterns in each stage.FindingsThe swimsuit patternmaking method proposed in this study was derived by considering the body shapes of middle-aged women, desired design and fabric characteristics. Also, a series of processes, including obtaining a raw pattern from the surface of the three-dimensional (3D) human body, designing patterns by the expert, evaluating patterns, drafting the final pattern and the final patternmaking method, was presented.Practical implicationsThis study has great significance to provide a manual of swimsuit patternmaking for middle-aged women, which has high tightness and movement compatibility.Originality/valueThe swimsuit patternmaking method proposed in this study is relatively simple because it is based on the human body measurements and delivers the lines and the calculated values clearly and objectively rather than the patterner's intuition does so that it is suitable for the automation of the swimsuit patternmaking for the middle-aged women.


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