Sliding mode control and Lyapunov based guidance law with impact time constraints

This paper analyses the issue of impact time control of super-cavitation weapons impact sxed targets which mainly refer to the ships or submarines who lost power, but still have combat capability. Control over impact time constraints of guidance law (ITCG) is derived by using sliding mode control (SMC) and Lyapunov stability theorem. The expected impact time is realized by using the notion of attack process and estimated time-to-go to design sliding mode surface (SMS). ITCG contains equivalent and discontinuous guidance laws, once state variables arrive at SMS, the equivalent guidance law keeps the state variables on SMS, then the discontinuous guidance law enforces state variables to move and reach SMS. The singularity problem of ITCG is also analyzed. Theoretical analysis and numerical simulation results are given to test the effectiveness of ITCG designed in this paper.