带有攻击角约束的无抖振滑模制导律设计

考虑到自动驾驶仪的动态延迟问题和攻击角度约束问题,根据寻的导弹拦截逃逸机动目标设计了一种新的无抖振的滑模制导律。首先,对视线角进行三次微分可得到制导系统的状态方程;其次,根据制导系统状态方程设计滑模算法,通过选取满阶终端滑模(TSM)滑动流形避免了TSM的奇异问题,在控制输入的导数项中引入切换函数项进行扰动补偿,有效消除了控制器中的抖振现象;最后,将提出的控制算法应用到制导律的设计中,保证了视线角在有限时间内收敛到期望值。通过与现存的有限时间制导律对比,本文设计的制导律不仅能够补偿自动驾驶仪的动态延迟而且能够有效消除控制器中的抖振现象。数字仿真验证了所提出的控制算法在制导律设计中的有效性。

Chattering-free sliding mode guidance law with impact angle constraint

Taking into account both the autopilot dynamics and impact angle constraint,a novel chattering-free sliding mode control guidance law for homing missile to intercept a target performing evasive maneuvers was proposed. Firstly, we establish the guidance system state equation by differentiating the line-of-sight (LOS) angle three times. Secondly, a new sliding mode control system is put forward based on guidance system state equation, and we choose full-order TSM (terminal sliding mode)manifold to avoid the singularity of TSM, and introduce the sliding mode switching term compensating the unknown bounded disturbance in the derivative of controller to eliminate the chattering phenomenon. Finally, we apply the new sliding mode control in designing the guidance law, which enforces the LOS angle convergence to desired value in finite time. Compared with the existing finite time guidance laws, this guidance law can not only compensate for the effects of the autopilot lag but also eliminate chattering phenomenon of controller effectively. The numerical simulation verifies the effectiveness of the proposed method in the design of guidance law.