Robust stochastic controller for a missile guidance system

This paper generalizes the previous results on the stabilizing property of a control scheme designed for a class of discrete-time nonlinear stochastic systems. The proposed controller was made more robust with a prescribed degree of stability by proper modifications. In this work the guidance process equations are represented by the kinematic equations of motion of a missile, and approximate equations of rotary motion of a missile around the center of gravity. These equations describe the missile motion in the vertical plane only. It is assumed that there is a symmetry between the vertical and the horizontal planes. The nonlinear equations are linearized in the discrete form. A state feedback controller is used for minimizing the error between reference states, which represent the system states when there is no noise, and the system states which are affected by noise. The noise is represented by white noise with zero mean and unit variance. In this paper, it is shown, by numerical examples, that when the guidance process is affected by the noise the target will be missed, and after applying the controller to the guidance process target impact will be achieved