Optimal Attitude Control of Large Flexible Space Structures with Distributed Momentum Actuators

TL;DR

This paper presents a distributed momentum actuator approach for large, lightweight space structures to improve attitude control stability and reduce vibrations, addressing challenges posed by flexible structures.

Contribution

It introduces a novel distributed actuator configuration and control strategy to enhance control authority and vibration suppression in flexible space structures.

Findings

Distributed actuators improve control authority over vibrations.

Expanded bandwidth reduces jitter and vibrations.

Lower settling times and structural deformation achieved.

Abstract

Recent spacecraft mission concepts propose larger payloads that have lighter, less rigid structures. For large lightweight structures, the natural frequencies of their vibration modes may fall within the attitude controller bandwidth, threatening the stability and settling time of the controller and compromising performance. This work tackles this issue by proposing an attitude control design paradigm of distributing momentum actuators throughout the structure to have more control authority over vibration modes. The issue of jitter disturbances introduced by these actuators is addressed by expanding the bandwidth of the attitude controller to suppress excess vibrations. Numerical simulation results show that, at the expense of more control action, a distributed configuration can achieve lower settling times and reduce structural deformation compared to a more standard centralized configuration.