A Midcourse Guidance Algorithm with Track Angle Constraint for Near Space Target Interception

For the multi-constraint problem in midcourse guidance stage of an interceptor which intercepts a near space target with double-pulse motor, a predictor-corrector guidance method based on head-on interception is proposed which can meet the overload convergence. In terms of the optimal control theory, the ZEM-ZEV guidance law is derived which can satisfy both the position and velocity constraints. The method uses the zero-effort-intercept manifold with the track angle constraint as the transfer conditions of the midcourse-to-terminal guidance. The numerical prediction method is used to solve the time-to-go with high accuracy. The velocity direction in the handover of initial-to-midcourse guidance and the ignition time of the second-pulse motor are introduced which can reduce the overload in the midcourse guidance stage. The results of the Monte Carlo simulation demonstrate that the proposed midcourse guidance algorithm can meet the requirements of the zero-effort-intercept manifold with the track angle constraint. It has strong robustness and excellent performance to the deviations and uncertainties of the model parameters. The algorithm has important theoretical significance and certain reference value for practical engineering applications. © 2020, Editorial Dept. of JA. All right reserved.