运输机外伸硬式桁杆系统控制律设计方法研究

对运输机上改装的外伸硬式桁杆系统,提出了一种控制律设计思路。通过风洞试验与力学分析建立飞机-桁杆系统耦合模型;在此基础上,通过特征根比对研究桁杆系统对原机飞控系统的影响,并对耦合模型进行降阶处理,建立了短周期模态结合桁杆系统运动模态的低阶模型;最后结合任务剖面特点,通过内环阻尼器结合外环PI控制进行桁杆系统姿态保持控制律设计,并进行仿真分析。结果表明桁杆系统不影响原机飞控系统正常使用;采用短周期模态结合桁杆系统运动模态的控制模型精度高,满足控制律设计要求;采用内环阻尼增稳结合外环PI控制的桁杆姿态保持控制的设计方法可行,具有重要理论参考意义。

A kind of control law design method is proposed for the transport aircraft overhanging rigid truss rod system. The coupling model of aircraft and truss rod system is established by the wind tunnel test and mechanical analysis, based on which the influence of the truss rod system on the original flight control system is studied by eigenvalue ratio. And the simplified control model composed of the short-period mode and the motion mode of the truss rod system is established. Finally, the attitude control law design for the truss rod system is achieved by the inner damper combined with the outer PI control according to characteristics of the task profile and the simulation demonstration is conducted, which shows that the truss rod system have little influence on the original aircraft system, and the high accuracy of the control model which is established on the short-period mode combined with the motion mode of the truss rod system is satisfied for the control law design. Therefore, the attitude control law design method which is achieved by the inner damping augmentation with the outer PI control is feasible and has engineering application value.