三旋翼飞行器动力学分析及建模

摘要

根据国内外旋翼飞行器的发展趋势,提出了三旋翼飞行器的研究方案.首先,介绍了三旋翼无人飞行器的机械结构,分析了它的整体物理力矩,理论解决了力矩相互抵消的问题.其次,对飞行器的起飞、俯仰、滚转、偏航等姿态进行了数学分析,建立了三旋翼无人飞行器的数学模型.最后,利用PID控制法和线性二次高斯(LQG)控制方法设计了三旋翼飞行器的控制器.实验结果表明,PID控制器振荡时间比较长,次数较多,没有达到理想状态;利用LQG方法对控制器进行了改进,对各个通道阶跃函数及脉冲响应函数仿真图的分析显示,系统改进后响应速度有了提高,2 s左右受控达到平衡.本文的研究为无人机的姿态控制提供了理论基础.%This paper proposes research schemes for a tricopter based on its developing trend.It focuses on its mechanical structures and physical moments and solves the problem that moments in the system offset each other.Then,it analyzes aircraft attitudes on launching,pitching,rolling and yawing by aerodynamic analysis and establishes a mathematical model for the tricopter.Finally,the PID and Linear Quadratic Gaussian(LQG) control methods are used to design a controller for the tricopter.The results show that the PID method does not achieve the desired states for its long equilibrium time and overmuch oscillations.However,after improving the controller by the LQG method,the simulation experiments on step functions and pulse response functions from different channels show that the response speed of the control has increased,and the balance of control can be implemented by about 2 s.the research can provide theoretical function for controlling aircraft attitudes.