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Research paper : Spinning process using robot technology (H. Arai)−153−Synthesiology - English edition Vol.5 No.3 (2012) a paper is required to be somewhat plausible, stringent verification of its feasibility is not required, and this does not necessarily influence the judgment in the peer review process. On the other hand, once the paper is accepted for publication, the entire content of the research, including the research objective, which may be mere fiction, is authorized. Such a made-up research objective is useful for affirming the reason for the existence of the research, and the same reason is often carried over to the following research. The existence of a previous study may justify a subsequent study. As the citation of a research objective is repeated and spread among several researchers, the fiction turns into a verified truth and may exist on its own. I myself became apprehensive when a research objective that I wrote with full awareness that it was fiction was cited by other researchers.When this research was started, industry and academia were separated in the robotics field. Although there have been many academic studies, the practical application of research results has been rare. A contributing factor might have been the problem of the fictionalization of research objectives. Until then, we had not been interested in industrial robots and manufacturing was not considered as an application target, which might have been the reason for not being able to do research on practical use. With this awareness, we started to seek topics of practical robot research in manufacturing.2.2 Encounter with metal spinningIn August 2001, the first H2A rocket was launched successfully. As the nose cone of the rocket was fabricated by manual metal spinning, this procedure was broadcast repeatedly on television. There was a monozukuri or manufacturing boom at the time. The author became aware of metal spinning during this time, and because of what can only be explained as intuition, embarked on this research.At first, the image was metal spinning carried out by a robot arm that consisted of a roller at the tip as an application of an industrial robot (Fig. 9), and it was considered as an example of engineering the artificial replication of skilled human labor. In robotics, force control of a robot arm has been studied for a long time, and considerable theoretical and technical know-how has been accumulated. However, since robot researchers were separate from the manufacturing industry, force control had been realized in only a few procedures such as assembly and grinding, and its effective application with high added value was still in the exploratory stage. In manual metal spinning, the sensory perception of the craftsman, particularly the perception of the force transmitted through the roller, plays a significant role. Also, since metal spinning involves incremental forming by partial deformation, the forming force is much smaller than that of other plastic forming processes. It was considered suitable for robots because of the many control parameters and the high degree of freedom. Since manual production was established as a business, it has been a high-mix low-production method with high added value, and we estimated that the profitability would be high if robot technology was introduced. Also in this research, there was a secondary intention of sending a message to other robot researchers. By presenting a specific case study of an excellent field of application where the advantages and potentials of robot technology could be utilized, we wished to arouse robot researchers’ interest in manufacturing.3 Research style and action principle3.1 Bottom-up research styleFor the author, this research was an outreach from the robotics field to the unfamiliar field of metal forming. Since we started with no preliminary knowledge, the research was commenced without preconceptions and progress took place in the dark. Therefore, we did not believe that the research goal would initially be set correctly, as mentioned in the previous section, and we took the stance that the goal was provisional. Therefore, we did not select a plan-driven method where a specific scenario for realizing a goal is set in a top-down style, and then the breaking down of the problem to the elemental technologies to be developed is carried out.Instead, the strategy taken was to stay with a vague research goal and temporary scenario, go ahead and make something, and carry out revisions as needed, under the loose direction of “realizing a technology that may be useful for metal spinning by applying robotics technology.” By operating an actual machine, the changes in the situation such as the progress of research, new inspirations, changes in awareness, and accidental external factors came into play. The research goal and scenario were changed frequently. For the elemental technology, whatever was available at the time was used, and the primary standard for the selection of elemental technology was that it was available and usable immediately. The technology developed was newly added to the inventory of elemental technologies. This was a bottom-up-style Fig. 9 Initial research concept (metal spinning robot)Robot armForce sensorSpinning rollerMandrelWorkpieceSpindle motor

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