摘要
To meet the requirements of the landing angle, miss distance, and control energy consumption, we study the optimal guidance law design for time-varying systems. In general, however, the optimal guidance law cannot be solved analytically. To solve the problem, we present a design method that combines the optimal control theory and segmental linear functions (SLFs). The optimal guidance law is designed using the proposed method. Ballistic simulations are conducted. Compared with the proportional navigation law, the optimal guidance law significantly increases the landing angle and decreases the miss distance. By averaging the time-varying coefficients of the optimal guidance law, we obtain a suboptimal guidance law. Simulations using the suboptimal guidance law are also made, and the results are compared with those of the optimal guidance law. The suboptimal guidance law is extremely simple and requires minimal onboard computational resources.