摘要本文对于四旋翼无人飞行器设计了一种轨迹跟踪控制器。首先,基于牛顿欧拉定律建立了四旋翼无人飞行器的非线性数学模型,然后引入奇异摄动理论,通过时间尺度分解的方法将系统分解成内环快子系统和外环慢子系统,再引入非线性动态逆的思想分别线性化快慢两个子系统,最后分别对线性化后的两个子系统设计控制器。针对内环慢子系统设计了 LQR控制器以稳定快速地控制飞行器角速度;针对外环快子系统设计了经典的PID控制器来跟踪所给定的轨迹。 最后,针对所设计的控制器搭建了 Simulink 仿真模型,仿真结果表明所设计的双环控制器能较好的跟踪所给定的复杂飞行轨迹。此外,还进行了实际的飞行试验,内环达到了良好的控制效果,从一定程度上证明了所设计控制器的可行性。 26002 毕业论文关键词 四旋翼无人飞行器 奇异摄动 非线性动态逆 PID LQR
Title Separate Frequency Modeling and Flexible Control of Quad-rotor Unmanned Aerial Vehicles
Abstract
This paper has implemented control strategy for path tracking control of quad-rotor
unmanned aerial vehicles. Based on Newton-Euler’s laws, the nonlinear
mathematical model of the quad-rotor is represented, and reduced subsystems
(inner-loop and outer-loop models) are obtained via time-scale techniques. The
two subsystems are linearized via nonlinear dynamic inversion approach. The
controlled inner loop via Linear Quadratic Regular control provides stabilization,
decoupling and angular rate control. For outer-loop controller design,
Proportional Integral Derivative control is utilized to ensure desired tracking
performance. The dual loop control structure, aiming at incorporating both
inner-loop and outer-loop control, is adopted to achieve sufficient stability and
tracking performance.
Simulation results indicate the developed flight control system of a quad-rotor
is competent and efficient enough for tracking the reference path. In addition,
actual flight test was carried out. It turns out that the inner-loop has a great
performance. To some degree, it proved that the controller works well.
Keywords Quad-rotor miniature unmanned aerial vehicles singular perturbation
approaches nonlinear dynamic inversion PID LQR
目 次