基于滑模方法的小型无人直升机混沌振荡控制

Chaotic Oscillation Control of Small Unmanned Helicopter Based on Sliding Mode Method

小型无人直升机具有主旋翼转速高、机身轻的特点。在配重失当、风力干扰情况下,机身会剧烈抖动,小型无人直升机的角速度甚至产生混沌振荡行为。控制小型无人直升机减轻、消除混沌振荡成为研究的重点。首先,给出了小型无人直升机的6自由度数学模型,并在悬停状态下,给出了该系统的线性化模型。其次,将该系统分为高度模型、航向角模型、X轴和Y轴位置模型、滚转角和俯仰角模型等几个控制部分,分别构建滑模控制律。运用指数趋近律方法消除滑模控制律的抖振问题。最后,仿真分析验证了该控制律可有效抑制小型无人直升机混沌振荡的产生,实现悬停状态。

The small unmanned helicopter has the characteristics of high rotation speed and light fuselage. In the case of improper weight and wind disturbance, the fuselage will shake, and the angular velocity of the small unmanned helicopter will even produce chaotic oscillation behavior. Controlling the small unmanned helicopter to reduce and eliminate chaotic oscillation has become the focus of research. Firstly, the 6 degrees of freedom(6-DOF) mathematical model of the small unmanned helicopter is given, and the linearized model of the system is given in the hovering state. Secondly, the system is divided into several control parts, such as height model, heading angle model, X-axis and Y-axis position models, roll angle and pitch angle models, and the sliding mode control law is constructed respectively. The exponential approach law is used to eliminate the chattering problem of the sliding mode control law. Finally, the simulation results show that the control law can effectively suppress the chaotic oscillation of the small unmanned helicopter and achieve the hovering state.