体自由度颤振主动抑制的多输入/多输出自抗扰控制律设计
沐旭升, 邹奇彤, 黄锐, 胡海岩
摘要：提出了一种新颖的抑制体自由度颤振（BFF,Body Freedom Flutter）的多输入/多输出（MIMO,Multiple Input/Multiple Output）控制律设计方法。该控制律将受控对象的不确定因素作为未知扰动,通过受控对象的输入/输出关系对其进行估计并给予补偿,最后综合出具有高鲁棒性的MIMO输出反馈控制律。为了验证所提出的控制律设计方法对于BFF抑制的有效性,选择一大展弦比飞翼布局无人机为研究对象,分别以机身升降舵与机翼外侧副翼为控制输入,飞机刚体俯仰率和翼尖加速度为反馈信号来设计MIMO自抗扰控制器。对闭环系统根轨迹分布、闭环时域仿真和闭环系统最小奇异值等进行了数值仿真,结果表明该MIMO自抗扰控制律设计方法能有效提高飞机BFF临界速度,可将飞翼布局无人机的BFF颤振临界速度提高约45.3%,并且具有很高的鲁棒性。
关键词：气动弹性力学，颤振主动抑制，飞翼布局飞行器，体自由度颤振，自抗扰控制器
Design of Multiple-Input/Multiple-Output Active Disturbance Rejection Controller for Body-Freedom Flutter Suppression
Xunsheng Mu, Qitong Zou, Rui Huang, Haiyan Hu
Abstract: The flying-wing aircraft has attracted extensive attention at home and abroad in recent years due to the advantages of high aerodynamic efficiency, long endurance time and excellent stealth performance. However, low-order elastic modes of the aircraft tend to be coupled with short-period rigid body modes under aerodynamic excitation, which induces a new flutter morphology - body freedom flutter. The re-search on BFF active suppression in the international aviation field has just started, and the design of MIMO BFF control law is rarely published. In this paper, a novel MIMO control law design method for suppressing BFF is proposed. This control law takes the uncertain factors of the controlled plant as un-known perturbation, estimates and compensates the unknown perturbation through the input/output relationship of the plant, and finally synthesizes the MIMO feedback control law with high robustness. In order to validate the effectiveness of proposed control law in the aspect of the suppressing BFF, a high aspect ratio flying-wing unmanned aircraft is chosen as the research object in this paper, and the MIMO active disturbance rejection controller is designed with the fuselage elevator and the outboard wing flap as the control input, the aircraft rigid body pitch rate and wingtip acceleration as the feedback signal. The numerical simulations of closed-loop root locus, time-domain simulation and minimum sin-gular value analysis were developed, and the results indicate that the presented MIMO active disturb-ance rejection control law design method could improve the BFF critical velocity effectively, specifical-ly, the BFF critical velocity of the flying-wing drone can be increases by about 45.3% with high robust-ness.
Keyword: aeroelasticity, active flutter suppression, flying-wing aircraft, body-freedom-flutter, active disturbance rejection controller
