摘要气动弹性的颤振问题广泛存在于航空航天、土木结构、风力发电及海洋平台等工程领域。当飞行器的飞行速度超过临界颤振速度时往往会引发机翼颤振，对飞行器造成极大危害。本文以带后缘控制面二元机翼为研究对象，研究非线性气动弹性机翼的颤振主动控制，用于抑制二元机翼由气动力、弹性力、惯性等各种因素引起的颤振问题，以提高飞机的稳定性、机动性和安全性。 

对于二元机翼的颤振问题，设计使用一种滑模控制方法对机翼的俯仰运动和沉运动进行控制，首先以准定长气动理论为基础建立二元机翼气动弹性模型，然后设计一种反演滑模控制器来实现对二元机翼颤振问题的主动控制并进行了仿真，最后由lyapunov定理证明了控制系统的稳定性。仿真结果表明，机翼的浮沉运动可以由初始状态的0.1m的偏差逐渐收敛到零点，调整时间为1s。俯仰角度也能在6s内由10°逐渐收敛为零并且能够保持在稳定状态，即所提出的反演滑模控制方法能够保证系统的稳定性并能有效地抑制颤振。62317

毕业论文关键词：二元机翼；反演滑模；气动弹性；颤振抑制；

Abstract The flutter problem of aeroelastic is widely existed in the fields of aerospace, civil engineering and wind power generation. When flight velocity exceeds the critical flutter velocity of self-excited vibration, it tends to cause catastrophic damage to the wing or tail. This paper mainly discusses the method of actively control the flutter of the nonlinear aeroelastic aerofoil and the research object is a two-dimensional airfoil equipped with a trailing edge surface. This method can be applied to the flutter surpression, which is caused by various factors such as aerodynamic force, elastic force, inertia and so on. Therefore it may contribute to improving the stability, maneuverability and safety of the aircraft. 

For the flutter of a two-dimensional airfoil, a method based on Backstepping Sliding Mode Control is introduced to control the pitching motion and plunge displacement of the two-dimensional airfoil in this paper. Firstly，an aeroelastic model of the two-dimensional airfoil is established on the base of the steady aerodynamic theory. Moreover the backstepping sliding mode controller is designed to manage to solve the airfoil flutter problems. Then the stability of the control system is proved according to the Lyapunov theory. The simulation results show that the plunge displacement can converge back to steady state from the initial state 0.1m in 1s. Furthermore the pitching motion can be controlled to go back to be stable from the initial state 10° in 1s. Therefore the proposed backstepping sliding mode control approach can guarantee the stability of the system and can effectively suppress the flutter.

Keywords: Two-dimensional Airfoil; Backstepping; Sliding Mode Control; Aeroelasticity; Flutter Surpression

第一章  绪论 1

1.1 引言 1

1.2 机翼颤振问题简述 1

1.4 弹性颤振国内外研究现状 2

1.4.1 非线性颤振 2

1.4.2 颤振主动控制 3

1.5 本文研究意义及内容 5

第二章  二元机翼气动弹性模型的建立 6

2.1 气动弹性力学概述 6

2.2 二元机翼气动弹性系统建模 8

2.4 颤振的临界速度 11

2.5 影响颤振速度的因素 11

第三章  反演滑模控制器的设计