Reduced-computation end-game steering laws for predictive guidance

Abstract

A reduced-computation end-game (RCEG) steering law is derived for predictive guidance and simulated for a class of command guided weapons. The RCEG law considers maneuver control system response dynamics and variable axial and normal accelerations. It substantially reduces the guidance computational burden, while achieving accuracy comparable to that realizable with iterative predictive guidance (IPG). With IPG, each iteration requires numerical integration of vehicle equations of motion to predict the miss distance, whereas the RCEG law is noniterative and requires no integration. RCEG guidance uses closed-form miss distance estimates based upon lumped-parameter rotational and translational dynamics. Results of a six-degree-of-freedom simulation of a hypersonic intercept weapon system indicate that the RCEG law, compared with a representative form of IPG, has miss distances that are statistically similar to those of IPG but a computational burden smaller by a factor of approximately 36.

A Methodology for Missile Countermeasures Optimization under Uncertainty

“…The time derivative of the line-of-sight angle λ is known as the line-ofsight rate. The effective navigation ratio for a given guidance system, also known as the guidance law gain, may be determined mathematically from a complex series of computations (Barron, 1995); for practical guidance systems, optimal values for N range between 3 and 5 (Ramo and Pucket, 1959).…”

“…It is important to note that by focusing entirely upon the identification of optimal sequences of aircraft maneuvers to be performed immediately prior to the predicted moment of impact, Zarchan's (1990) analytical approach identified what amounts to an end-game solution (Barron, 1995) to the MCO problem. This approach cannot effectively handle uncertainty about either the type or current state of the SAM, and cannot be extended to combine maneuvers with additional countermeasures.…”

“…The problem of optimizing aircraft maneuvers to evade incoming surface-launched antiaircraft missiles (SAMs) has been the subject of extensive research in the fields of game theory and automatic control systems (Shinar and Steinberg, 1977;Krasovskii and Subbotin, 1988;Grimm and Well, 1990;Zarchan, 1990;Barron, 1995). Closed-form solutions to simple versions of the Missile Countermeasures Optimization (MCO) problem require the evading aircraft to execute specific sequences of maneuvers at precisely known distances from the pursuing missile.…”

A genetic programming methodology for missile countermeasures optimization under uncertainty

“…The time derivative of the line-of-sight angle λ is known as the line-of-sight rate. N' may be determined mathematically from a complex series of computations [2]; for practical guidance systems, optimal values range between 3 and 5 [3].…”

“…The missile countermeasures optimization (MCO) problem has been the subject of intensive research [12], [6], [13], [2]. Closed-form analytic and control-theoretic solutions require the evading aircraft to execute specific sequences of maneuvers at precise distances from the pursuing missile.…”