带鸭翼的弹性高超声速飞行器非线性控制

高超声速飞行器纵向静不稳定、非最小相位和突出的弹性效应等特性给飞行器控制系统设计带来严峻挑战。针对该问题,文中采取鸭翼作为附加俯仰控制舵面与升降舵进行联动控制的策略,以改善高超声速飞行器的非最小相位特性和严重的弹性效应,从而达到提高控制性能的目的。首先,给出了考虑弹性模态的高超声速飞行器动力学模型;其次,研究了鸭翼对飞行器非最小相位特性以及弹性模态响应的影响,并给出合适的鸭翼布局位置和鸭翼/升降舵联动增益参数;最后,采用基于反馈线性化方法和LQR理论的非线性控制器对弹性飞行器进行控制,对比分析了鸭翼联动控制对闭环控制性能的改善作用。研究结果表明,合理的鸭翼配置可以缓解系统的非最小相位特性带来的不利影响,同时避免了控制输入对特定弹性模态的激励,从而达到提高弹性高超声速飞行器控制性能的目的。

Nonlinear control of flexible hypersonic vehicles with canard

For a hypersonic vehicle with unstable longitudinal dynamics, non-minimum phase and severe aeroelastic effects, the design of flight control system is a challenging task. The feasibility of the strategy using canard in conjunction with the elevator as an additional factor is investigated, aiming to eliminating the non-minimum phase behavior and suppress the elastic mode, and to improve the performance of control system. First, a flight dynamic model with flexibility effects is presented. Second, the effects of the placement and relative ganging gain of the canard on the non-minimum phase behavior and elastic modes are demonstrated. At last, with the design of a nonlinear controller based on feedback linearization and LQR technology, the performances of the strate-gies with and without canards are comparatively evaluated. The simulated results show that, with the placement and relative ganging gain carefully chosen, the proposed control strategy provides an increased level of closed loop performance by suppressing the non-minimum phase behavior and eliminating control excitation of the first elastic mode.