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Nowadays, the flight distance of champion team of the birdman rally contest was over 400 m. In order to break the record, we have to consider the weather conditions, flight conditions and design optimization of the glider. For this purpose, we developed the three-dimensional flight simulator and the optimization program based on genetic algorithm. The simulation result of the three-dimensional flight simulator was reasonably agreement with the real flight. GA (Genetic Algorithm) optimization was carried out with two hundreds samples and fifty generations. The dominant genes of airplane for the contest were obtained with GA. The performance map showed the optimal airplanes such as the champion team were sensitive and not easy-handle. The simulator was suggested another optimized model with flexible wing that was not sensitive to flight conditions. The proposed model got the fourth prize and the referee's award of the birdman rally contest 2005., JAXA Special Publication, 宇宙航空研究開発機構特別資料

A method is presented for the optimum aeroelastic design of a flapping wing employing lifting-surface theory as an aerodynamic tool and the complex method as the optimization algorithm. The method is applied to the optimum design of a flapping wing of a Kite Hawk (Milvus migrans) UAV (Unmanned Aerial Vehicle) and the optimum thickness distribution of the main-spar is determined. As the result of the optimization, a high propulsive efficiency of 75 percent is attained considering only dihedral flapping of the main spar. By evaluating the viscous effect for this optimum design using a three-dimensional Navier-Stokes code, the effectiveness of the design is confirmed., JAXA Special Publication, 宇宙航空研究開発機構特別資料

The orbital dynamics of magnetoplasma sail (MPS) is investigated focusing on the required acceleration for escape from the solar system. One of the main features of the MPS propulsion system is that the thrust in confined to anti-sun direction. This motivates the study of the orbital motion under an outward continuous radial acceleration as a function of the distance from the central body. Two representative cases in terms of the MPS power system are analyzed; one is the constant radial acceleration case, and the other assumes the radial acceleration inversely proportional to the square of the radial distance. The former corresponds to constant power case such as Radioisotope Thermoelectric Generator (RTG) system, while the latter corresponds to the case assuming solar paddle for the MPS power system., JAXA Research and Development Report, 宇宙航空研究開発機構研究開発報告