Impact time guidance for large heading errors using sliding mode control

Impact time and angle constrained integrated guidance and control with application to salvo attack

“…From cos( (0) − M (0)) > 0 (implied by Assumption 1) and the fact that cos( (t) − that there exists a time interval t ∈ [T 1 , T 2 ] (where T 1 ≥ 0 and T 2 < T 3 ) such that cos( (t) − M (t)) > 0 and cos( (t) − M (t)) is a decreasing function of time t; combining this with cos 2 + sin 2 = 1, it follows that | sin( (t) − M (t))| is an increasing function of time t in t ∈ [T 1 , T 2 ]. In addition, combining cos( (t) − M (t)) > 0 with (2), it follows thaṫr < 0 namely r(t) is a decreasing function of time t. From (3), it follows that…”

“…Remark 10. It is noted that in all literature on both cooperative and individual guidance [1][2][3][4][5][6][7]10], only the engagement geometry (4) was involved to generate the missile acceleration, and the missile dynamics (1) was not considered, causing it to have no autopilot. However, in this paper, based on the IGC scheme, the engagement geometry (4) and the missile dynamics (1) are integrated to design directly the commanded (reference) value of the elevator deflection (which is a more realistic control input), exploiting fully the coupling between guidance and autopilot.…”

“…Salvo attack, where several missiles launched from the same or different platforms are required to hit the target simultaneously, is an effective way of destroying a large target (such as ships, submarines and tanks) equipped with advanced anti-missile defence systems (for example, the close-in weapon systems (CIWS)) [1,2]. Salvo attack can be achieved in two ways.…”

“…Hence in cooperative homing the missiles are required to be equipped with a communication device, which increases the cost and complexity of the scheme [8,9]. The second approach is individual homing [1,2,10], in which a common impact time is commanded (pre-specified) to all missiles in advance, and thereafter each missile tries to hit the target at the pre-specified time. This is a more promising way for multiple low-cost missiles attacking a single target simultaneously from various directions.…”

“…This approach combines the engagement geometry with the missile dynamics and directly yields the elevator deflection (which is a realistic control input) to change the velocity direction in the missile control systems. In the current literature [1][2][3][4][5][6][7]10], only the engagement geometry was studied, using the missile normal acceleration as the control input; and the missile dynamics were not considered (which hence ignores the coupling between the engagement geometry and missile dynamics), resulting in no autopilot. 2.…”