Abstract
Lure fishing and fly-fishing have been positioned as sports deliberately different from the traditional Japanese fishing-style. In the case of fly-fishing, casting is the element which anglers must master in order to cast a fly, done so by using the weight of a line. This study uses experimental and computational analysis to investigate the dynamic behavior of a fly line. Fly-fishing is constituted by various elements, but the importance that casting holds is extremely large. Fling speed, the casting process and the loop shape of the line while in flight are important for the proper presentation of flies. Moreover, the shape of a fly line is also important for a long cast or controlled cast. Therefore, the most suitable casting method will be clarified from the viewpoint of sports engineering and human dynamics. There are some types of casting techniques, overhead cast, side cast, false cast (forward cast and back cast), double haul cast and roll cast. In the case that there is an obstacle something like a tree, anglers can not do back cast while the false cast. In such situation, anglers have to select “Roll cast”. Roll cast consists of only forward cast. The arms motion of roll cast is different from the motion of forward cast. Therefore, the initial condition at the time anglers start the roll cast is important for the appropriate casting. In this paper, a rod, a line and arms are modeled by using rigid bodies and links. The time history behavior of the model is calculated by pseudo angler velocity of the arms. The difference of the arms motion between forward cast and roll cast is evaluated. And the line behavior with respect to the initial condition that anglers start casting is clarified.