Robust Active Mirror Control Based on Hybrid Sensing for Spacecraft Line-of-Sight Stabilization

Abstract

Modern space observation missions demand stringent pointing requirements that motivated a significant amount of research on the topic of microvibration isolation and line-of-sight stabilization systems. While disturbances can be reduced by mounting some of the noisy equipment on various isolation platforms, residual vibrations can still propagate through and be amplified by the flexible structure of the spacecraft. In order to alleviate these issues, the line-of-sight must also be actively controlled at the payload level. However, such systems typically have to rely solely on low frequency sensors based on image processing algorithms. The goal of this paper is to present a model-based control methodology that can increase the bandwidth of such systems by making use of additional rate sensors mounted on the main disturbance elements impacting the optical path. Following a comprehensive model identification and uncertainty quantification part, the robust control strategy is designed to account for plant uncertainty and provide formal worst-case performance guarantees. Excellent agreement between theoretical prediction and experimental results are obtained on a test bench developed at the European Space Agency.

Integrated modelling of microvibrations induced by Solar Array Drive Mechanism for worst-case end-to-end analysis and robust disturbance estimation

“…All the models derived in TITOP approach have been recently implemented in the last release of the Satellite Dynamics Toolbox (SDT) [13,14,15], which allows the user to easily build the model of a flexible spacecraft with several appendages by assembling elemental Simulink customized blocks. This model is then ready for robust control synthesis and robust stability and performance assessment [3,16,17] by using the available Matlab routines of the Robust Control Toolbox [18].…”

Linear Fractional Transformation modeling of multibody dynamics around parameter-dependent equilibrium

“…The approach is originally limited to tree-like structures, but it extends to closed-loop kinematic chains of flexible bodies [29]. The resulting model is provided under the form of a block-diagram with minimal number of states, and the parameters can be isolated to obtain a minimal LFT model [30], allowing robust control [31] or integrated control/structure co-design with the H ∞ synthesis [32]. This framework was applied to stratospheric balloons, which can be modeled as multibody structures composed of rigid bodies connected with revolute joints [33].…”

Compound Attitude Maneuver and Collision Avoiding Control for a Novel Noncontact Close-Proximity Formation Satellite Architecture

“…With the development of the space camera technology, highresolution imaging under attitude maneuver has been focused on recently [1][2][3]. However, the imaging results could be declined seriously by the huge flexible solar array and the vibration-generating devices [4][5][6].…”