The sitting position is very common in everyday life and therefore any garment should be comfortable in that positon. It is especially important for those who are disabled and are confined to a sitting position throughout life. These include paraplegics whose restricted movements are due to paralysis of the lower limbs and restrict them to a wheelchair. Garments for a sitting position should meet certain particular needs like the body dimensions and postures of each individual. Design considerations should provide ergonomic comfort in a sitting position and include functional requirements due to limitations of strength and mobility in such a way that they do not cause additional health problems to paraplegics, e.g. skin irritations, pressure sores, obstruction of the blood flow etc., but rather to improve the quality of life for paraplegics. Today, the development of garments is practically impossible to imagine without the assistance of 3D CAD systems for the virtual prototyping of garments, which usually provide only the 3D body models in a standing position. The aim of this study was to explore the possibilities for the virtual prototyping of garments in regard to the sitting position, using the OptiTex 3D commercial CAD system. For this purpose 3D scans of subjects in sitting position were performed using a general-purpose ATOS II 3D optical scanning system. In addition, processing techniques of the human body mesh modeling and surface reconstruction techniques were involved to obtain a sitting 3D body model. The garments' basic pattern designs for a standing position were constructed according to the rules of the M. Müller&Sohn construction system. Their reconstruction into garments' basic pattern designs for a sitting position were performed by using the virtual measured dimensions of the scanned 3D body model in a sitting position, and virtual prototyping of the garments. Comparisons between the dimensions of the real and the 3D body models were carried out, as well as a comparison between the real sewn and virtually developed garments. The research showed that a reliable sitting 3D body model was achieved by used scanning technology, modeling and reconstruction techniques, as well as the usefulness and effectiveness of the virtual prototyping of the garments for a sitting position. In this study fully mobile individuals were involved to avoid unnecessary burdening of paraplegics in this stage of the research. The experiences gained from this study will enable us to include paraplegics within the study during the scanning and anthropometric survey with the aim of designing a general parametric 3D body model. Its body dimensions and postures would be possible for adapting from able-bodied persons with the purpose of developing individual garments for paraplegics.

This study examined the effects of ultrasonic welding parameters on bond strength, seam thickness and seam stiffness, as well as water permeability. For study purpose, two types of four-layered fabrics with same compositions and different areal densities suitable for inner part of sport shoes were used. Two different types of seams, lapped and superimposed, were applied for ultrasonic welding and also compared by traditional seam applied by shoe manufacturer. The morphology of different type of seams was also analyzed to observe the influence of welding parameters on the layers during the ultrasonic welding process. Bonding strength was found to depend on the seam type and composition of the joined fabric layers. It was confirmed by the shoe manufacturer that all the produced welded seams provided the requested minimum bond strength to be suitable for the use of the shoes. The traditional seams applied by the shoe manufacturer were thicker but had lower stiffness in comparison to all welded seams. It was also found out that ultrasonic welding damaged the membrane, which was confirmed by no water resistance of welded seams. Statistical analysis showed that ultrasonic welding parameters, such as welding frequency and velocity, influence the bond strength, thickness, and bending stiffness of welded seams, but the obtained results were statistically insignificant.

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In this research, the use of new technologies for the development of special protective overall for sport aircraft pilots was studied, with a focus on a comparative analysis of the static and dynamic body postures’ dimensions, intended for the development of the overall’s pattern design. For this purpose, digitalization of five male persons was carried out with the 3D human body scanner Vitus Smart by using 3D printed markers, precisely positioned on defined body locations, intended for exact measurement of body dimensions. Male persons, aged between 19 and 35 years with the same athletic body type and different body heights and body mass indexes (BMIs), were scanned in a standard static standing body posture and three dynamic body postures. A comparative analysis between the static and dynamic body postures was carried out. Based on the established body dimensions and girth dimensions of the 3D body model with 3D-modeled compression elements, made-to-measure construction of the overall pattern design was carried out. The function of these compression elements is redistribution of the blood from the lower extremities to the upper body parts at the appearance of high g-forces. Therefore, increased girth dimensions due to the use of compression elements were applied in the overall development process as construction measures with needed ease allowances. The functionality of the developed special protective overall was explored on the scanned 3D body model with 3D-modeled compression elements in a real sitting posture of the sport aircraft pilot in a cab by using virtual prototyping. The virtual simulation technology showed that a well-fitted protective overall for sport aircraft pilots can be developed by using a 3D scanned body model of a person in a sitting posture and its 3D body dimensions.

Selection of suitable sewing needle is one of the most important parameters for ensuring an effective and fault‐free sewing process. This task requires good knowledge of basic characteristics of a sewing needle, i.e. needle type, point shape and needle fineness. Also good knowledge of sewing materials is required. The contribution presents an analysis of important parameters that influence the sewing needle selection in women’s underwear production. The importance of those parameters in ensuring the appropriate seam quality is described. The selection of a suitable sewing needle was carried out on the basis of analysis of influential sewing parameters with application of machine learning from examples.