Homing Guidance – An AFSM Approach

This paper presents a new adaptive fuzzy sliding mode algorithm for homing guidance of vehicles, under the presence of unknown target maneuverings. The well-known proportional navigation guidance (PNG) is the optimal solution to the linear homing problem for non-maneuvering targets and with the assumption of a zero-lag autopilot. The effectiveness of the classical PNG, however, degrades considerably in the presence of maneuvering targets and realistic autopilots. Recently, various combinations of Adaptive, Fuzzy and Sliding Mode Control (AFSMC) techniques have been successfully applied for control of uncertain nonlinear dynamical systems. The extension the AFSMC technique to the case of homing guidance problem is proposed in this paper. The new method, namely, the AFSM Guidance, or AFSMG method is shown to lead to smaller lateral accelerations for intercepting the weaving targets, as compared to the previously existing guidance methods. Another advantage of the AFSMG is that it just needs information about the rate of change of the Line Of Sight (LOS) and is independent of the target acceleration, which is hard to measure in many real situations. Various simulation results demonstrate the reliability and stability of the proposed AFSMG approach.