Robust Control of Non-linear Flexible Spacecraft


1 Department of Civil Engineering,Amirkabir University of Technology

2 Department of Aerospace Engineering,Amirkabir University of Technology

3 Department of Electronical Engineering,Amirkabir University of Technology


In this paper, the problem of attitude control of a 1D non-linear
exible spacecraft is
investigated. Three controllers are presented. The rst is a non-linear dynamic inversion, the second is
a linear -synthesis and the third is a composition of dynamic inversion and a -synthesis controller. It
is assumed only one reaction wheel is used. Actuator saturation is considered in the design of controllers.
The performances of the proposed controllers are compared in terms of nominal performance, robustness to
uncertainties, vibration suppression of panels, sensitivity to measurement noise, environment disturbance
and non-linearity in large maneuvers. To evaluate the performance of the proposed controllers, an
extensive number of simulations on a non-linear model of the spacecraft are performed. Simulation results
show the ability of the proposed controller in tracking the attitude trajectory and damping panel vibration.
It is also veri ed that the perturbations, environment disturbance and measurement errors have only slight
e ects on the tracking and damping responses.