Study On Vibration Control Of Spacecraft Antenna Based On Wave Method

The large meshed structures in spacecraft antennas,is easy to vibrate with the dense vibration modes at low frequency range once disturbed.Wave method,which can be used to analyze the motion of the spacecraft antenna accurately,has a great advantage over modal method by avoiding truncate relatively higher modes.In the wave method,vibration of a structure is considered as the combination of two traveling waves,and can be controlled by altering wave transmission.Here,dynamic analysis for large meshed structures in both frequency domain and time domain are carried out,and feedforward control experiments are performed as well,to prove the controllable vibration of meshed structures.The main work of this paper is as follows:1.Dynamic analysis of large meshed structures in frequency domain is achieved by programming with MATLAB,and then subspace iterative method and circular transfer matrix method are proposed.These methods have a great advantage over traditional transfer method,making the dynamic analysis on the large meshed structure more convenient and rapid2.A time-domain wave method is carried out in a form of analytical solutions.Besides,a MATLAB program is programmed to ensure wave solution can be transferred freely from frequency domain to time domain,opening the doors for getting dynamic response of large meshed structures under stimuli.3.A platform for feedforward control on the vibration of the meshed structure is set up,and the dynamic characteristic of the meshed structure with and without frame are tested.The effect of actuators’ number on the control strategy is also investigated.The experimental and theoretical results indicate that feedforward control based on wave method makes a distinct contribution to vibration control,making the vibration cut off up to 75% and even more.