An increase in national income generally increases the level of interest in marine leisure activities and the demand for vessels used for such activities. As sale yachts approximately 30 ft in length have recently gained global popularity, many of these vessels have been manufactured in many countries, including South Korea. International competitiveness in sale yacht manufacturing can be achieved only through the satisfaction of conditions related to exterior design and price competitiveness based on the performance and price of fittings and production process efficiency. A steering system is an essential vessel device for marine navigation; it is connected to a rudder to enable an operator to control the direction of the vessel. Both the steering system and sails are main vessel equipment that require the operator to control them appropriately with less power applied (Song et al., 2017). Although the steering system serves as the core facility for sail yachts, South Korean manufacturers have primarily imported most components of these systems, such as the pedestals, sheaves, chain gears, and quadrants have been imported. The steering system requires a considerable amount of time and labor for its installation in the body of a sail yacht owing to connections to various components, such as those mentioned above. Hence, its price competitiveness is affected significantly. In this study, methods for improving the structural stability and functionality of existing steering systems and reducing the cost of these systems based on their characteristics were investigated. Accordingly, a steering system modularization method based on the development of components that can replace imported components for reducing manufacturing cost and increasing productivity during production is proposed. In addition, it is confirmed that the proposed method increased the price competitiveness of the developed steering system and its technological competitiveness through performance enhancement.
Structure and Modularization of Steering Systems
Overview of Steering SystemsSteering systems in sail yachts are devices connected to rudders and are used to change the direction of the vessels. They are classified into tiller-and wheel-based steering systems based on steering methods. Furthermore, they can be categorized into single-and twin-wheel steering systems according to wheel operation methods (Miyata et al., 1998(Miyata et al., /2006. Fig. 1 shows the process of operating a steering wheel system. When the steering wheel is rotated to change the direction of the sail yacht, the torque from the wheel is transmitted to a rudder and used to change the direction of the sail yacht. The components involved in transmitting the wheel torque to the rudder include a steering wheel, cable sheave, bulkhead, quadrant, and a rudder on a steering stand.