Yuka Takai

Motion Analysis of Weaving “Kana-ami” Technique With Different Years of Experience

The technique of making “KANA-AMI” is traditional craftsmanship in Kyoto. All wire net fabrications are made by the hand work, so that it is expected that the craft man has the exquisiteness of motion. The purpose of this study is to clarify the characteristics of motion during the weaving the wire nets with different years of experience.The subjects were three males whose have experienced wire netting craftsman for 44 years, 8 years and 0 years respectively. The working environment was reproduced in the laboratory so that the subjects might work usual like working environment as much as possible and they could concentrate on them work. The infrared reflection markers were affixed at 21 points on the body of the craftsman to analyze motion during the wire netting. And six cameras (hawk-i Motion Analysis Co. Ltd.) captured the position of each marker, and all markers position data which synchronized were taken in by a computer (sampling rate: 100Hz). It was defined that right to left direction was X axis, front to rear direction was Y axis, top to bottom direction was Z axis for subjects. In addition, shape and degradation of wire net were evaluated. The shapes of hexagonal pattern were evaluated. Degradation of wire nets were evaluated by salt spray tests.Copyright

Biomechanics Investigation of Skillful Technician in Spray-up Fabrication Method

Spray up fabrication has been used for forming composite structures since ancient times as it can be performed as long as the mold, skills, and materials are available. Hence highly specialized control technique and the tradition of skill are required to ensure the consistent stability of product quality. In this study, the authors thus conducted a motion analysis experiment using hand lay-up fabrication experts as subjects. The experiment, seemingly a new and only attempt in Japan, quantified techniques that are not visibly apparent and considered to be tacit knowledge. The dimension stability of samples was measured, and their relationships with the motions of experts were also evaluated. It was also suggested that highly specialized control techniques, the appropriate training of non-experts, and technical tradition are possible.

Mechanical Property of CFRP by Carbon Spray Up Method

Spray up method is one of methods for composite molding and it is traditional and common molding method that can deal with various shapes according to workmen skill. The essence of the composite molding impregnates resin to fiber;, in other words, is to substitute air included in the fiber for resin. Spray up method can spray matrix on mold together while cutting reinforcements continually, and the cutting of the reinforcement, setting up and the impregnation of the matrix are carried out at the same time. That is why working process is made efficiency and can cope with a design change easily. However, the quality of the composites depends on the techniques of workmen and the judgment with Spray up technique is too difficult, because it has not clarified that the difference of that techniques has how influence with manufactured products. In addition, in a spray up method, glass reinforcements is usually used, but carbon reinforcements is not put to practical use. High quality is required with the CFRP composite, and this is because it is thought that techniques of Spray up method does not satisfy this demand. In this study, motion analysis was used to compare the difference between Spray up techniques by expert and non-expert. Expert’s carrier of Spray up was 19 years and non-expert’s carrier was a year. Motion analysis, which is applied to various fields like sports or traditional crafts and so on, can visualize human motion. The Mac 3D System was used as equipment, since it is the most powerful tool for the motion capture and analysis particularly. The sampling rate was 60 Hz. The object of this study was to contribute that technique back to fabrication fields by analyzing and considering what was important factor. Furthermore, this trial is thought that leads to the development of new technology. As the result, the motion of expert’s lower half of body indicated different motion compared with non-expert one. Expert’s centroid moved smoothly and his motion showed constant tendency. On the other hand, non-expert’s motion was awkward in several points and his motion didn’t show the tendency like expert. Furthermore, The CFRP structures that manufactured with Spray up method are cut for the tensile testing. Tensile test were performed by using an Instron universal testing machine under a speed 1mm/min. Spray up technique is discussed based on the motion analysis method and moreover it is shown that Spray up method is useful in CFRP materials production.Copyright

Analysis on the Three-Dimensional Wire Orientation of ‘Kana-Ami’ Metal Network Between Expert and Non-Expert

As well known, Kyoto has been the capital city of Japan for one thousand years. The long ancient culture brings out a serious of traditional craft products, such as ‘Kana-ami’ — a kind of metal wire network. ‘Kana-ami’ was all made by hand work, for this reason there was no industrial pollution produced during the manufacturing process. In other words, ‘Kana-ami’ is a kind of green manufacturing product, and its processing motion and working experience make a big effect on final products’ quality. Product’s quality was judged by the standard structure of ‘Kana-ami’, which was established after a long period of history and culture accumulation. That aesthetical standard has already been consistently rooted into Japanese peoples’ heart deeply. Dated back to around 50 years, there were about 30 handmade wire net shops in Kyoto. However, it has decreased dramatic until 7 shops now. Therefore, it is urgent time to pay attention to this severe reality and try to do something to keep this traditional culture wealth and continue green manufacturing technique and skill to the next generation.In this study, the expert and non-expert were employed as the target investigated subject from ‘Kanaami Tsuji’ workshop. Investigated subjects were required to fabricate a Kana-ami product, which was investigated by 3D motion capture during product’s fabrication. The structural features of final products by expert and non-expert were illustrated and compared by the numerical analysis. The moment of scoop tofu was recorded by high-speed camera in order to clarify the small differences on product performance. In a word, the great effort is to reduce the final products impact to the surface of tofu.Copyright

Research on the Performance of Three Tea Whisks of “The Way of Tea” with Different Experience

In this paper, three kinds of Japanese tea whisks’ influence on bubble form in “the way of tea” process were investigated. The bubble form and distribution state by each whisk after 30 %, 50 %, 80 % and 100 % of tea making finishing time were recorded and analyzed through numerical processing. In order to verify the quality of tea whisk, two tea masters were employed as expert and non-expert, and three kinds of tea whisks’ performance were evaluated and compared during the whole tea making process. The expert can controlled three tea whisks very well.

Experience Factors Influence on Motion Technique of “The Way of Tea” by Motion Analysis

In this paper, the difference technique of motion and process for “The way of tea” on were investigated. The expert and beginner’s motion and trace were captured by High-speed camera system. In order to verify the correct motion technique, a tea master and three people were employed as expert and beginner, and two kinds of motion techniques and moving tracks were summarized and compared during the whole tea making process. The expert’ motion can be considered as a good reference.

Comparison of Characteristics Recognition in the “Mitate” of Urushi Crafts

Urushi crafts is one of the Japanese traditional crafts. Urushi painting and “Maki-e” decoration of these Urushi crafts works were removed by usage for many years. Experts of Urushi crafts have repaired and restored them correctly by gain an insight into their conditions, materials and techniques. They can understand the contained information by watching the works. This observation method is called “Mitate”. In this study, it was aimed to examine how to conduct Mitate when Urushi craftspeople look at the works. As a result, it is considered that expert craftspeople could ensure the characteristics recognition by gaining and combining more information from the work than the other subject.

Mechanical and optical properties of silk fabric/glass fiber mat composites: an artistic application of composites

Currently, hybrid glass fiber-reinforced plastics (GFRPs) have attracted increasing attention as gradually common used materials. Glass/silk fiber hybrid reinforced plastic (GSFRP), a new kind of material, is designed aiming to create a kind of opaque effect of specific use. Three types of silk/glass composites with five layers of glass mats and a single layer of woven silk fabric lamina with small, medium and large crepe are fabricated by using the hand lay-up method to compare with pure GFRP. Optical properties, including the light transmission property and luminance distribution, were examined with regard to the specimens of GSFRP. Results indicate that light was diffused more efficiently by GSFRP than pure GFRP laminates. Moreover, the greater the crepe degree of silk fabric is, the more efficiently light is diffused and the rise of luminance suppressed. Furthermore, mechanical properties, including the flexural as well as the impact property, were examined through three-point bending and Izod tests, respectively. There is little negative influence on the flexural strength of GSFRP when silk inserted in layer 3 and, as the crepe degree of silk fabric increases, a slightly inferior effect on the impact test presented. From the scanning electron microscopy observation, it is found that the existence of silk fabric inserted in layer 3 could prevent further propagation of the crack and alleviate the delamination of the specimens during the bending process, improving resistance to delamination and bending.

Comparative Analysis of Wheelchair Transfer Movements Between Nurse and Care Worker

It is considered that, even though it is for the same purpose, there is a difference in the methods of body position changing or wheelchair transfer between nurses and care workers. The authors had attempted in the previous study to develop a self-learning support tool for nursing students. As a part of the previous experiment, wheelchair transfer method discussed in the nursing technique textbook commonly used among nursing students was extracted. Then, this movement was filmed in order to produce an “example video”. We showed this “example video” to our test subjects consisting of care workers, and asked them to imitate the wheelchair transfer movement shown in the video. During this experiment, we received feedbacks from the test subjects that claimed; “We do not take this approach when transferring an elderly to and from a wheelchair in care work”. Even though care worker are all categorized as “care profession”, there are positions, such as Certified Care Worker and Certified Social Worker, that require national qualifications. There are also positions, commonly referred to care worker, that does not require any qualification. An unqualified care worker is required to receive the initial training seminar, and one of the professions that are qualified to become the instructor of this seminar is nurse. If there is a difference in the methodology between nurses and care workers, it means that the techniques taught by nurses were transformed through time in order to adapt to the environment of frontline care work. As movements involved in body position changing or wheelchair transfer are type of technique that is physically demanding and could potentially cause backache for both nurses and care workers, it is highly significant that the current technique is improved and becomes an easier technique for the practitioners. Therefore, in this study, we engaged veterans of both nursing and care work, measured their movement during body position changing and wheelchair transfer, and examined the characteristics of movements of each subject. In general, the location where a nurse conducts the movement in discussion is a hospital ward. On the other hand, it would normally be a facility such as a nursing home for a care worker. Between a hospital ward and a care facility, there are many differences such as the legally required size of a room or the fact that one place is for medical treatment and the other is for living, resulting in dissimilarities such as the positioning of beds. By exploring the difference in the movement of nurses and care workers, while taking these factors into consideration, it is possible that improved methods for body position changing and wheelchair transfer that are better adapted to the environment could be devised.

Expert’s Common Factor of Painting Motion in Auto Repair Painting Process

This study aimed to develop a learning system for studying the coating and painting tasks performed in automobile repair. This study analyzed and compared the characteristics of skilled spray gun handling for automobile repair painting with those with little experience. The spray gun movements and postures of 10 participants were measured using a motion capture system. The results showed the distance between the door and the experts’ body to be approximately 1 m. The experts kept their axillae closed, bent an elbow, and set the distance between the door and the spray gun to approximately 0.22 m. The experts’ spray gun running speed was faster than that of non-experts, and the speed reduced at the door panel edge. The experts’ body movement realized a uniform thickness coating.