@article{oai:kitami-it.repo.nii.ac.jp:00008007, author = {羽二生, 博之 and 鈴木, 聡一郎 and 武田, 修平}, issue = {630}, journal = {日本機械学會論文集. B編}, month = {2016-11-22}, note = {When a manipulator is operated in water, fluctuating fluid forces produced by vortex formation will cause problems in precised positioning control of the manipulator. However, in this kind of studies to date, people were mainly interested in control theory of linearizing the nonlinear drag evaluated from assumption of constant drag coefficient, and nobody paied attention to the fluctuating fluid forces due to vortex formation. On the other hand, the presence of strong irregularity in vortex shedding from a two dimensional bluff body ill uniform flow is reported by number of researchers. Therefore, nonrepeatability of fluctuating fluid forces acting on a manipulator arm repeatedly commencing its motion in still water is expected to appear. In this study, two kinds of circular cross sectioned manipulator arms were provided. Then, one was towed and the other was swang in still water. In eatch case of motion, variation of fluctuating lift with towed distance or swing angle was measured for one hundred times. From ensembly collected data at particular towed distance or swing angle, presence of nonrepeatability of fluctuating lift was clarified.}, pages = {642--647}, title = {水中マニピュレータに作用する変動流体力 (静水中で反復的に動き始めるときの渦形成に基づいて作用する変動揚力の非反復性)}, volume = {65}, year = {} }