This paper combines the nonlinear Udwadia-Kalaba control approach with the Assumed Mode Method to model flexible structures and derives an attitude controller for a spacecraft. The study case of this paper is a satellite with four flexible cantilever beams attached to a rigid central hub. Two main topics are covered in this paper. The first one is the formulation of the equation of motion and the second one is the nonlinear controller design. The combination of these two techniques is able to provide a controller that damps the vibration of a flexible structure while achieving the desired rigid-motion state.

中文翻译：

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挠性航天器的非线性控制器设计

本文将非线性Udwadia-Kalaba控制方法与假定模式方法结合起来，对挠性结构进行建模，并推导了航天器的姿态控制器。本文的研究案例是一个卫星，其四个柔性悬臂梁连接到刚性中心轮毂。本文涵盖两个主要主题。第一个是运动方程的公式，第二个是非线性控制器设计。这两种技术的组合能够提供一种控制器，该控制器可在实现所需的刚性运动状态的同时，衰减柔性结构的振动。