Satellite vibration control using frequency selective feedback

This paper addresses the problem of actively attenuating the vibration of plates on satellites. A pure feedback controller is demonstrated which operates at a set of dominant frequencies in a disturbance spectrum, where the control path model is estimated on-line. A new feature of the frequency selective feedback is the use of the inverse Hessian to improve adaptation speed. The control scheme also incorporates a frequency estimation technique to determine the relevant disturbance frequencies with higher precision than the standard fast Fourier transform (FFT). The controller is implemented on a test rig to demonstrate the practical feasibility of the method. A disturbance with three rational dominant frequencies is introduced. If FFT were used instead of the frequency estimation method proposed, then a large number of samples would be required to accurately estimate the disturbance frequencies, and, most importantly, FFT-estimated frequencies could lead to an unstable control system due to their granularity. Using the proposed frequency estimation method, the total achieved attenuation is 26 dB on the experimental rig.