Abstract:

To meet the requirements of the low-cost rockets for hypersonic flight tests, a synchronized control scheme is proposed for controlling the procession and nutation of a rocket through a simple reaction control system (RCS), which can achieve the large-scale attitude adjustment and reentry control. The RCS consists of a single nozzle with nonadjustable duration of jet-flow. Firstly, the spinning rocket dynamic processes with the control of RCS are analyzed. Then the system models and the stability conditions, which show the coupled effects of precession and nutation, are established. Finally, the RCS control strategy is designed with the help of the attitudes and the angular rate information. Moreover, the control strategy can make the rocket attitudes meet the demands. The theoretical simulation results demonstrate that the large-scale adjustment of the pitch angle (+10°～-60°) can still be achieved under the condition that the relative error of RCS impulsive moment is 26.7% and the variation range of spin angular rate is 2.0~4.0 r/s. This method is applicable to the low-cost rockets for hypersonic flight experiments, and promotes the development of the extensive flight experiments for hypersonic research.

Key words: Hypersonic, Spinning rocket, Attitude control, Reaction control system (RCS), Precession, Nutation