Pitch handling characteristics of the stratospheric airship based on moving mass control

In this paper the pitch handling characteristics of the stratospheric airship without rudder and elevator based on moving mass control are analyzed. First of all, the common moving mass control mechanisms are introduced, and the mathematics model is established. Then, the static and dynamic handling characteristics are respectively analyzed. It is indicated that, through the rational allocation of proportion of the movable mass in the total weight, with the movable distance, the moving mass control mechanisms can produce relatively large pitch control torque, and have high efficiency, low energy consumption, no need of sustained energy consumption. But the moving mass control mechanisms are static trim mechanisms in essence, which means, at a fixed amount of control, as airspeed changes, the control moment cannot compensate for the changing aerodynamic moment, difficult to implement fine-tuning. It is hard to adjust the pitch angle to a small amount of low drag state for the open-loop control of moving mass control mechanisms. Finally, the above conclusions are verified by flight tests.