A Study of Large Flexible Space Structure Control Using γ-Passivity

本研究的目的是：1)提出一种基于Gamma无源概念的控制器设计方法；2)对大型柔性空间结构振动的Gamma无源控制进行验证。该方法的特点是使我们能够指定控制系统的增益和相位裕度，并保证对常见的非结构不确定性的鲁棒稳定性。指出H_无穷控制作为一种标准的鲁棒控制系统设计方法，并不是指定期望的增益和相位裕度。因此，本研究提出的方法比H_无穷大控制方法更灵活。并对柔性结构控制方法进行了实验验证。控制的目的是抑制结构的振动和调整结构的角位置。控制的难点在于角位置的运动会刺激结构的高频振动。因此，在位置的沉降性能和振动之间存在折衷。针对这一困难，需要设计控制系统来改善系统的调节性能，并保证未建模高频动态的鲁棒稳定性。伽马无源控制，更广泛地说，是一种基于耗散性概念的控制，从理论和实验上都证明了它是有效的。

The purpose of this study is 1) to develop a controller design method based on the notion of gamma-passivity and 2) to validate the gamma-passivity control for the vibration of large flexible space structures. The feature of the method is to enable us to specify gain and phase margins of control systems as well as to guarantee the robust stability for usual unstructured uncertainty. The H-infinity control which is known as a standard design method for robust control systems is pointed out not to be specify desired gain and phase margins. Therefore, the method proposed in this study is more flexible than the H-infinity control. An experimental validation of the method has been made for a flexible structure control. The aim of the control is to suppress the vibration and to regulate the angular position of the structure. The difficulty of the control is that the movement of the angular position stimulates high-frequency vibrations of the structure. Consequently, there is a tradeoff between the performance of settlement of the position and vibration. Toward such difficulty, the control system should be designed to improve the regulation performance and to guarantee the robust stability for unmodelled high-frequency dynamics. The gamma-passivity control, more generally, a control based on the notion of dissipativity has been shown to be effective the requirement mentioned above, theoretically and experimentally.