2015 年 63 巻 2 号 p. 68-76
Unmanned helicopters are widely used in various industrial applications. Conventional unmanned helicopters equip stabilizer-bar on their rotor system, and it is effective to slow the gust response of the helicopter. However, the stabilizer-bar has brought about increase of complexity and inefficiency. The purpose of our work is to develop unmanned helicopters without stabilizer-bar system. In this paper, a model of flapping motion of the stabilizer-bar is derived. A model of flapping motion of the rotor blades and interactive dynamical model of the helicopter is derived, and a lower-dimensional model is also discussed. It was found that the lower-dimensional model was good approximation of the original model in the frequency domain which is important for the unmanned helicopter's flight. Flight experiments were carried out for the evaluation and the collected data were consistent with the proposed model. In conclusion, the model of the functions of mechanical feedback of the stabilizer-bar is developed. Moreover, the drawback of the stabilizer-bar is also elucidated. Our results shows that electrical control system can replace the stabilizer-bar as the stability augment system and it is possible to improve not only gust response but maneuverability of unmanned helicopters.