变体飞行器链式平滑切换控制
Chained smooth switching control for morphing aircraft

针对变体飞行器在连续变形过程中的高度保持和姿态稳定问题, 提出了一种平滑切换状态反馈控制器设计方法. 建立了纵向运动的链式平滑切换系统模型, 相比于传统的任意切换律和硬切换方案, 所提出的模型能够更准确的反映变形过程的运动特性, 且降低了设计的保守性. 推导了链式平滑切换系统有限时间有界且具有鲁棒性能指标的充分条件, 将增稳控制器设计转化为具有线性矩阵不等式组约束的优化问题. 所设计的控制器虽然放宽了对系统渐近稳定性的要求, 但能够保证系统状态在变形时间段内有界稳定, 且兼顾了实际的舵偏响应. 控制算例和非线性仿真验证了所提方法的有效性.
Considering the altitude-keeping and attitude-stabilization during the continuous transformation of the morphing aircraft, we propose a design method for the smooth switching state feedback controller. A class of chained smooth switched system model for the longitudinal motion is built. This model is more precise in approximating the transition dynamics than the hard switching scheme with arbitrary switching law; it can also reduce the conservatism of the control design. The sufficient condition is derived for ensuring the finite-time boundedness and the robustness performance of the chained smooth switched system. The design problem of the stability- enhancement controller is translated to an optimization problem involving linear matrix inequalities. Although the obtained controller relaxes the requirement of asymptotic stability, it guarantees that the system states to be boundedly stable during the variation process, and also synthesizes the elevator characteristics. The numerical example and nonlinear simulation are given to illustrate the efficacy of the proposed approach.