CFD simulation is an effective means to know and control fluid dynamics in competitive swimming, although it requires a method which is capable of computing highly complex flow with deforming human body. In this paper, we focus on dolphin kick swimming and simulate flow around human body. To implement the simulation, a male swimmer model is made, and movement of human body is captured from video footage. Also, a moving grid finite volume method is used. This computational approach completely fulfills geometric conversation law, so that moving boundary problems become resolvable. For swimmer model to move unrestrictedly, a moving computational domain method is utilized. Furthermore, coupling of kinematics nad these methods allows swimmer model to dynamically accelerate and decelerate by the forces applied to itself. The result shows that most of the thrust is produced in down-kick, and the ring vorticity is genrated in the wake, which appears in practical dolphin kick swimming.

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Following the 33rd America's Cup which featured a trimaran versus a catamaran, and the recent 34th America's Cup in 2013 featuring AC72 catamarans with multi-element wing sail yachts sailing at unprecendented speeds, interest in wing sail technology has increased substantially. Unfortunately there is currently very little open peer-reviewed literature available with a focus on multi-element wing design for yachts. The limited available literature focuses primarily on the structures of wings and their control, rather than on the aerodynamic design. While there is substantial available literature on the aerodynamic properties of aircrafy wings, the differences in the flow domains between aeroplanes and yachts is significant. A yacht sail will operate in a Reynolds number range of 0.2 to 8 million while aircraft operate regularly in excess of 10 million. Furthermore, yachts operate in the turbulent atmospheric boundary layer and require high maximum lift coefficients at many apparent wind angles, and minimizing drag is not so critical. This paper reviews the literature on wing sail design for high performance yachts and discusses the results of wind tunnel testing. Two wings with different symmetrical profiles have been tested at low Reynolds number with surface pressure measurements to measure the effect of gap geometry, angle of attack and camber on a wing sail's performance characteristic. It has been found that for the two element wing studied, the gap size and pivot point of the rear element have only a weak influence on the lift and drag coefficients. Reynolds number has a strong effect on separation for highly cambered foils.

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This paper reports on the analysis of the characteristics for each position in curling based on shot-scores. We computed average shot-scores for each position using 14 game information about college-top level teams, and analyzed the correlation between the differences of average shot-scores and the differences of final game scores. The results show that strong correlations appeared on the results of the lead positions and the fourth position, and no correlation for second position and third relates to the game progress. There is possibility to predict game results and game progress based on short-score for each position.

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A curling robot that can deliver the stone in Curling has been developed. The curling robot is aim to win in curling game with human. In previous paper, we reported mechanism and system of our stone delivery robot, physicals simulator to calculate the movement of the stone on the ice sheet and operation simulator for determining the delivery parameters. The result of game which performed developed curling robotic system vs. human was also reported. The result indicated the need to improve the system. This paper deals with improvement of an operation simulator and the result of second game against human team. The operation simulator improved consideration of probability of delivery error and parameter adjustment of evaluation function. Then, curling game was simulated by using new operation simulator against previous operation simulator. The curling robot had a curling game with human team using the new operation simulator. The curling robot lost the game even though there was no time limit. Evaluation result of new operation simulator and detailes of a game result and its evauation was reporter in this paper.

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Recent high-precision measurements of curling stone dynamics have revealed several funcamental behaviors of a curling stone on an ice sheet. The main results obtained so far are briefly reviewed and some novel experiments are suggested to obtain deeper insight into the curling stone dynamics.

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Curling is a game with an advanced strategy called "Chess on Ice." However, there has not been much research on strategy in the field of systematic artificial intelligence. Since some researches are arguing about the strategy on a respectively original curling simulator, it is difficult to compare the superiority between these algorithms easily. We propose a new server system "Digital Curling" as a field about which these can argue in common. This system has realized an ideal curling sheet using physical simulator. If a client system connects with this server and a candidate move is sent, a simulator will calculate with a constant normal random number and return the actual move to the client. We introduce the system in detail. We show the validity by interview against the curling players and by the success of the competition on this system.

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Friction coefficient of a curling stone was measured with high-precision digital image analysis in order to obtain its relation to the translational velocity and speed of rotation. Movement of the curling stone near the house was recorded in the sequential images with the camera located on the ceiling. Calibrations to remove lens aberration were done prior to the experiment. The translational velocity was calculated using the positions of the stone derived from the sequential images. Then the friction coefficients were calculated from the decrease of the translational velocity, and analyzed with consideration of the relative velocity to ice including the effect of rotation. It was found that the friction coefficients become larger when the translational velocity is smaller with a maximum around 0.1 m/s.

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