Dynamics of a Fly Line

—Forward Cast with 2 Link Casting System—

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 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. Flying 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. Fly casting has an aspect that is one of the means to place lightweight objects in places that are difficult for humans to reach using flexible strings. The lightweight objects are expected to be applied to transport in a wide range of spaces by constructing a casting system. Therefore, this study focuses on the constructing a casting system with reference to fly casting. In the past studies, fly casting was not applied to transport. Only the flight shape of the line was focused on. In this study, a two-link casting system that reproduces the movements of the human forearm and wrist is created. The possibility of that the system can transport lightweight objects in forward casting would be shown.