中文摘要：

研究气动参数摄动和外界扰动下高超声速飞行器姿态系统的鲁棒自适应控制问题.引入特征建模的思想对高超声速飞行器的姿态系统建立二阶差分方程模型.考虑到高超声速飞行器再入过程要经历飞行环境的剧烈变化的特点,为了提高闭环系统的瞬态响应性能和抗扰能力,设计了黄金分割鲁棒自适应控制器.该控制器具有与特征模型相似的结构,控制器参数通过在线辨识获得,并且按照黄金分割比生成控制信号,能够保证辨识参数收敛过程中系统的稳定性.基于混合H2和H∞控制思想对标准的黄金分割自适应控制器中的参数λ进行在线优化,从而保证了姿态回路对气动参数摄动和外界扰动具有满意的鲁棒性.所提出的λ（k）优化算法是通过对一组线性矩阵不等式求解得到的,因此易于工程实现.改进后的黄金分割鲁棒自适应控制算法在自适应性和鲁棒性的优越性使得该方法尤其适用于高超声速飞行器姿态控制系统.仿真结果验证了控制方法的有效性和实用性.

英文摘要：

This paper is concerned with the mixed H2 and H∞ adaptive control for hypersonic vehicles during reentry phase. The dynamics of the angle of attack in the longitudinal plane is modeled by using a second-order difference equation known as the characteristic model. In order to improve the transient per- formance in the presence of large aerodynamic coefficient variations and unknown exogenous disturb- ances, a more intelligent golden-section robust adaptive control law with the similar structure as the char- acteristic model with golden-section parameters, is proposed based on our previous work. In addition to easy implementation and guarantee of stability before the convergence of parameter estimation, this new a- daptive control law contains an adjustable parameter A （k） that guarantees H2 and H∞ robustness of the system, and is calculated based on the linear matrix inequality approach. The integration of adaptive con- trol and robust control provides the attitude control system for hypersonic vehicles with the capability to accommodate large flight conditions in a reliable way. Simulations are carried out on a hypersonic vehiclewith a high lift-drag ratio during the reentry phase, and the effectiveness and practicability of the control scheme is verified.