由于高超声速飞行器具有飞行速度快、机动能力强等特点,因此,传统的制导方式难以保证拦截弹拦截高超声速飞行器时的制导精度。为了减小弹目相对速度,降低对拦截弹的过载能力要求,按照前向制导方式,设计了有限时间收敛的三维前向滑模制导律。该制导律采用了连续的快速双幂次趋近律,不仅保证收敛速度快,同时削弱了传统制导律中存在的抖振现象。在此基础上为了处理系统扰动的上界未知的问题,又设计了自适应滑模制导律,该制导律既可以处理未知上界的外部扰动又可以保证第一种制导律所具有的良好特性。运用李雅普诺夫稳定性理论对所设计的滑模制导律进行了理论证明,最后,通过数值仿真验证了所设计制导律的有效性及优越性。
Traditional guidance method is difficult to ensure the interceptor's guiding accuracy in intercepting a hypersonic vehicle due to the vehicle's fast flight speed and high maneuverability. To reduce the relative velocity between the target vehicle and the interceptor, and lower the overload requirement of the interceptor, a three-dimensional head-pursuit sliding mode guidance law is presented. The guidance law adopts continuous fast double-power reaching law, which can ensure the convergence speed and weaken the chattering phenomenon caused by traditional guidance laws. Based on these, a three-dimensional head-pursuit adaptive sliding mode guidance law is designed to deal with the problem of unknown upper bound of the external disturbance. The guidance law can not only deal with this problem, but also can ensure the good characteristics of the first controller. The sliding mode guidance laws are proved by the theoretical perspective based on Lyapunov stability theory. Finally, the correctness and effectiveness of the methods are verified by numerical simulation.