A New TurbineSail Coupled Propulsive System for Autonomous Sailboats * Autonomous sailboats are good candidates to perform longterm missions in oceans since they are windpropelled. Furthermore, wind turbine is a useful device that can provide autonomous sailboats with necessary electrical energy to support controller, drive rudder and sail. Some current applications for onboard wind turbines can reduce fuel demand of autonomous power sailboats. Apart from necessary electrical energy supply, autonomous sailboats also need enough propelling forces to move efficiently in the direction of the course.In this paper, we propose a new turbinesail coupled system that utilizes wind sources by adding two vertical wind turbines on both sides of the sail. Experiments are conducted in a wind tunnel. The results show that the system can increase the maximum propelling force when sailing downwind and allow further regulation of the force by slowing the rotation speed of wind turbine on one side.

Wing Sail Landyacht Modeling And System Verification Winddriven vehicle is a kind of promising way to utilize wind energy due to its nonpollution feature. This paper presents a practical design of the winddriven vehicle in the form of landyacht, which is equipped with a wing sail and a microcontroller unit. Theoretical analysis and simulation were performed to find the total force coefficient corresponding to each combination of attack angle and heading angle, and the best attack angle corresponding to each different heading angle. A prototype was built and tested in a windfield environment. The simulation and experiment were concordant, both of which showed the relation between the movement of landyacht and these angles when moving upwind well.