Finite-Time Convergent Sliding-Mode Guidance Law for High-Speed Flight Vehicle with Bearings-Only Measurement

Aiming at the problem of a high-speed flight vehicle accurate tracking a target on the ground, a finite-time sliding-mode guidance law during the whole guidance period is proposed. Different from the traditional tracking guidance problem which believes that the acceleration of non-cooperative targets is known, this paper uses filtering method to obtain target motion parameters. First of all, the model of the vehicle-target tracking is established in the planar. Then, by combining the finite-time control and sliding-mode variable structure control methods, the finite-time sliding-mode guidance law is developed, and the designed guidance law's finite-time stability proved theoretically. Furthermore, the extended Kalman filter (EKF) is used to estimate vehicle-target relative range, relative velocity, and target acceleration involved in the guidance law during the whole guidance period, in which the vehicle equips a passive seeker that the bearings-only measurement (BOM) is available. Finally, numerical simulations demonstrate it can provide good performance for the filter.