Abstract
Underactuated flying object of this research imitates a helicopter. The helicopter is applied in a large field from ability of flight such as vertical ascent, vertical descent and hovering. Especially manned helicopter is used for rescue, emergency activity and fire fighting at the time of disaster, and unmanned helicopter is precious sources of information in the danger spot where people cannot approach. However the helicopter is complex and a nonlinear system. Moreover, change of the center of gravity by collapse of cargo piles is considered as a cause of the plane crash in recent years. In this research, we examine the relation of the frequency response for pitch angle and the center of gravity of underactuated flying object in order to consider the stabilization method of the orientation.
