抄録
In this study, a wooden javelin that conformed to the current length and weight regulations for javelin throw competitions was produced, and various characteristics were measured and compared with those for javelins of three other materials measured in a previous study. The reproduced wooden javelin was confirmed to not differ from the other javelins in shape, weight, position of the center of gravity, or relative size of each part, thus meeting current regulations for javelin throw competitions. The moment of inertia about the short axis through the center of gravity for the wooden javelin was much smaller than that for the other javelins. The resonant frequency of the wooden javelin at the first mode was much lower than that of the other javelins, but the compliance at the loop and the tail and the position of the node were not dramatically different between the wooden javelin and the other javelins. Compared with the other javelins, the wooden javelin had much lower static bending stiffness and bent more than the others by far, by approximately 3-fold. Furthermore, in javelins used for competitions, the relationship where the resonant frequency at the first mode is low such that the static bending stiffness is large was applicable to the wooden javelin.
