基于二步线性化的实验直升机模型跟踪控制

Tracking control for 3-DOF helicopter model based on 2-step feedback linearization

一种基于二步反馈线性化方法设计解耦跟踪控制器,应用于一个三自由度(3-DOF)直升机实验系统。3-DOF直升机实验模型是典型的高阶多输入设计的多输出系统,具有较强的通道耦合和非线性特性。基于该仿真平台,将线性化系统分解成两个子系统,定义输出为输出误差积分以实现积分控制,按照输入-输出线性化方法通过坐标变换和输入变换对其线性化模型全状态精确线性化,实现了系统完全解耦,对扩展系统按照线性LQR方法设计跟踪控制器。计算机仿真和实时控制表明系统能够很好的跟踪高度和旋转速度参考轨迹。

A method of trajectory-tracking based on integral control realized by 2-step input-output linearization for a laboratory 3 degrees of freedom （3-DOF） helicopter model is introduced. The 3-DOF helicopter is a typical multi-input multi-output system with high-order. It has small channel coupling between pitch and travel acceleration. The tracking error integral is defined as the plant output, and the real model is transformed equivalently into a model without coupling by applying input-output linearization to the two subsystems hierarchically. Then, the method of linear quadratic regulator （LQR） is utilized to obtain the gain of the state feedback for the decoupled system. Simulation and real-time experimental results demonstrate that the designed system can track the given reference trajectory through the proposed method effectively.