旋转柔性梁系统振动频响特性分析及振动抑制

VIBRATION FREQUENCY RESPONSE FEATURE ANALYSIS AND VIBRATION SUPPRESSION OF A ROTATING FLEXIBLE BEAM

航天器挠性附件或柔性机器人等柔性旋转梁系统的模态阻尼小,由于扰动,或者在调姿及转动时,大幅值的振动将持续很长时间,这将影响系统的稳定性和指向精度,因此,必须对振动进行主动控制。提出一种基于加速度传感器反馈的复合控制算法,快速控制系统设定点及转动过程的振动。建立挠性旋转梁试验平台,进行了基于加速度传感器和压电片传感器的试验模态激励分析、振动频响特性分析。并根据振动特性选取加速度反馈控制算法的相应参数,利用交流伺服电机驱动器抑制旋转梁设定点的振动、旋转过程的振动主动控制进行了试验研究。试验结果表明采用提出控制方法能够快速地抑制系统的振动,验证了特性分析和提出控制方法的可行性。

Rotating flexible beam system of spacecraft flexible appendages or flexible manipulator has characteristic of lower modal damping,so large amplitude vibration will last for a long time due to external disturbance excitation and effect of orientation regulation or rotation,it will affect stability and directing accuracy of a system,thus,active vibration control must be adopted.A combining control strategy based on feedback of acceleration sensors is adoped to suppress the unwanted vibration.The experimental setup of a rotating flexible beam is built to verify the proposed control approach.Experimental investigations are carried out based on modal identification and vibration frequency response feature analyses and vibration control with acceleration sensors and PZT sensors.The parameters of the control algorithm can be obtained from the dynamic characteristics,and the experimental study applying the proposed algorithm to AC servomotor actuator for set-point and rotating process vibration control are conducted.The experimental results show that the vibrations are significantly suppressed,thus the feature analysis and the proposed control method are effective.