基于MPSP的次优滑模制导律

Sub-optimal sliding mode guidance law based on MPSP

针对导弹拦截机动目标的问题,提出了一种能满足多终端约束的次优滑模制导律(Sub-OSMG)。该算法将模型预测静态规划(MPSP)与滑模控制(SMC)相结合,解决了MPSP在系统模型不精确时由于依赖模型预测而导致的控制量发散问题;基于三自由度相对运动方程建立所提出的制导律,其鲁棒性通过Lyapunov稳定性理论进行了证明;在滑模控制的设计中引入一种较为新颖的滑模面,巧妙地继承了两种方法的优点,其区别于传统扩展比例导引(APN),在仅知机动幅值的情况下,能精确地击中目标。仿真结果表明,所提出的Sub-OSMG能够有效地抵消外部扰动,具有更高的精度、更好的鲁棒性、更小的控制代价。

A sub-optimal sliding mode guidance law（ Sub-OSMG） which can satisfy the multiple terminal constraints is proposed for missile to intercept maneuvering target. By combining sliding-mode control（ SMC） and model predictive static programming（ MPSP）,the results divergence problem of MPSP due to excessive dependence on model prediction when system model is inaccuracy can be solved successfully.The guidance law is established based on three degree of freedom motion equation and its robustness against disturbance is proved by Lyapunov theory. In sliding mode control a new sliding surface is introduced,so the proposed guidance law can inherit the merits of the two methods,it is therefore different from the conventional guidance law like APN and can accurately hit the target with only the maneuvering amplitude. Simulation results show that the Sub-OSMG is of higher accuracy,better robustness and lower control cost,and could effectively counteract the external disturbance.