基于PZT和脉冲调制控制的挠性卫星振动抑制

针对推力器作为执行机构的挠性卫星大角度姿态机动时帆板的振动抑制问题，提出了伪速率（PSR）调制式喷气控制与基于压电陶瓷（PZT）材料的主动振动控制技术相结合的复合控制方法．该方法的前者是采用传统的PD控制，利用四元数和角速度作为反馈信号，并基于Lyapunov方法证明了姿态的渐近稳定和模态振动的衰减性；另外，为了减少推力器的非线性开关控制激起的挠性结构振动，采用PSR的准线性调制技术使推力器产生所需要的控制力矩的脉冲序列，从而实现大角度姿态机动控制；后者是通过设计正位置反馈（PPF）补偿器以增加结构的阻尼，进一步抑制挠性结构残余振动．数值仿真结果表明，该方法不仅能够使航天器完成对姿态的机动，而且能够抑制帆板的弹性振动．

Vibration reduction of flexible satellite using pseudo rate modulated thrusters and smart materials during attitude maneuvers

This paper presents an approach to vibration reduction of a flexible spacecraft during rest-to-rest maneuvers by using a Pseudo Rate Modulator(PSR) for thruster firings and smart materials for active vibration suppression.Based on quaternion and the angular rate,the Lyapunov technique is applied in the design of a PD controller,which is able not only to stabilize the spacecraft attitude but also suppress vibrations of the flexible solar panels.The PSR modulation is used to control the on-off thrusters for attitude maneuvers to reduce vibration introduced to the flexible solar panels,which can be considered as a passive means for vibration reduction.Nevertheless,some residual micro-vibrations may be present.On the contrary,the technique of PPF control using smart materials as sensors/actuators is more suitable for suppression of micro-vibrations,i.e.,fine tuning the system at the final stage of operations, which is desirable for precision pointing of advanced spacecraft.Simulation results demonstrate the proposed approach can significantly reduce the vibration of the flexible appendages during and after the maneuver operations.