风洞试验绳牵引并联支撑系统自适应滑模控制
Adaptive sliding mode control of wire-driven parallel suspension system in wind tunnel tests

针对绳牵引并联支撑系统在风洞试验中的应用，提出一种自适应滑模控制方法以提高飞行器模型动态试验的运动精度。首先，详细分析了系统不确定因素，并重点考虑了气动力与绳弹性变形的影响，重构了系统动力学方程；基于奇异摄动理论，提出一种复合控制律，其中对慢变状态量采用自适应连续非奇异终端滑模控制，对快变状态量采用微分控制；通过李雅普诺夫函数法对系统的稳定性进行了分析，确定了控制律中微分增益项的影响。最后，以两种典型的动态轨迹为例，考虑气动力建模，对所设计控制律进行多参数仿真分析。结果表明该复合控制律可以减小绳弹性以及气动力等不确定性参数对跟踪误差的影响，提高运动控制精度，因此该控制方法有效可行，可为绳牵引并联支撑的动态试验应用提供理论指导。
Adaptive sliding mode control method is proposed to achieve high precision motion of aircraft model, which is suspended by wire-driven parallel robot in wind tunnel tests. Firstly, uncertainties in system parameters are analyzed in detail, and the aerodynamic forces and wire elastic properties are especially considered in the reconstruction of system dynamic equations. Secondly, a composite control law is designed based on the singular perturbation theory, in which slow variables are dealt with adaptive continuous non-singular sliding mode control, and fast variables are coped with differential control. Then, stability of the overall closed-loop system is analyzed through Lyapunov function method, and differential gains in the control law are determined. Finally, two typical dynamic test trajectories for aircraft model are taken as examples. Taking aerodynamic forces into account, numerical simulation is conducted by using this compound control law. Simulation results show that the tracking error induced by parameters uncertainties and elastic properties could be decreased by the proposed control method, and it’s quite effective and feasible, which could provide theoretical guidance for the wire-driven parallel suspension system in dynamic wind tunnel tests