系统收敛时间和攻击角度控制的滑模导引律

Sliding Mode Guidance Law With Impact Angle and Convergence Time Control

针对打击机动目标带攻击角度约束的导引律设计问题,采用滑模控制理论、任意收敛时间控制方法和干扰观测器,设计了一种攻击角度和收敛时间控制的导引律。根据弹目相对运动关系,将目标机动和建模误差等视为干扰,构建了考虑攻击角度约束的制导系统状态方程。分析了任意收敛时间控制方法在干扰情况下的性能,采用滑模控制和干扰观测器对任意收敛时间控制方法进行改进,提升鲁棒性。将该方法用于滑模面和趋近律设计中,采用干扰观测器对系统扰动进行估计,基于滑模控制理论,结合制导控制系统状态方程,推导出了收敛时间和攻击角度可控的滑模导引律。相比有限时间收敛导引律,该导引律的收敛时间和攻击角度可直接设定,无需根据制导参数计算。设置不同的目标机动方式以及不同的攻击角度和收敛时间,进行了多场景的数值仿真。结果表明,所提导引律能够有效实现攻击角度和收敛时间控制,并精确命中目标,同时相比现有导引律其制导性能更佳。

Aiming at designing the guidance law for attacking maneuvering targets with impact angle constraint,a guidance law with impact angle and convergence time control was proposed by using sliding mode control theory,arbitrary convergence time control method and disturbance observer.According to the relative motion relationship of the missile and the target,the state equation of guidance system considering impact angle constraint was constructed,and the target maneuver and modeling errors were regarded as the disturbance.The performance of the arbitrary convergence time control method in the case of interference was analyzed.The sliding mode control and disturbance observer were used to improve the robustness of arbitrary convergence time control method.The method was applied to the design of sliding mode surface and approach law,and the disturbance observer was used to estimate the system disturbance.Based on the sliding mode control theory combined with the state equation of the guidance control system,a sliding mode guidance law with convergence time and impact angle control was derived.Compared with the finite-time convergence guidance law,the convergence time and impact angle of the guidance law can be set directly without the calculation of guidance parameters.By setting up different target maneuvers,different impact angles and convergence times,numerical simulations under various cases were carried out.The results show that the proposed guidance law can control impact angle and convergence time effectively and hit the target accurately.At the same time,the guidance performance is better than that of the existing guidance law.