高超声速巡航飞行器在线自适应反馈控制设计

由于飞行器模型的强非线性,各种建模不确定性以及飞行环境的复杂性,高超声速飞行器控制成为一个研究难点.针对某类具有参数不确定性的非线性系统,提出了一种反馈线性化与自适应估计相结合的方法,对非线性系统的输入输出动态应用反馈线性化处理以得到拟线性模型,并设计反馈控制律;对不确定参数采用自适应在线估计,利用Lyapunov方法分析稳定性;针对选择不同输出的情况,对如何消除内动态进行了讨论.为了验证该方法的可行性,将其应用于某高超声速飞行器巡航段纵向非线性模型,对速度和高度通道进行跟踪控制仿真,由于飞行器和大气环境存在建模不确定性,利用自适应控制对不确定参数进行在线估计.仿真结果显示该方法能够快速收敛,并且具有良好的在线自适应能力.

Adaptive feedback control design for hypersonic cruise flight vehicle

Because of strong nonlinear characteristics, modeling uncertainties and complicated flight environment, the control of hypersonic flight vehicle becomes a challenge. An approach which combines feedback linearization and adaptive control for a multiple-input-multiple-output(MIMO) nonlinear system with parameter uncertainty was proposed. Feedback linearization was used to obtain the linear input-output dynamics and a feedback controller was designed. The uncertain parameters were estimated online by an adaptive control law and the Lyapunov method was introduced to analyse the close-loop system stability. For the conditions of choosing different outputs, a discussion was made on how to remove the inner dynamics to avoid unexpected unstable dynamics. A hypersonic cruise flight vehicle longitude model was used to testify the reliability of the proposed approach. In order to control altitude and velocity channel, a feedback controller with adaptive online estimator was designed for the parameter uncertainties in vehicle model and atmosphere model. The simulation was operated to track the altitude and velocity step commands. Results show the controller has good tracking performance with rapid converge speed.