A sliding mode controller design for a missile autopilot system

Abstract

A description is given of an application of sliding mode control (SMC) for stabilizing the static and dynamic characteristics of an anti-aircraft missile. The solution provides effective separation of the control process from the dynamics of the missile airframe. In the equivalent part of the stabilization system a linear-quadratic regulator (LQR) is considered, and an analytical method of selecting the weighting elements of the amplification matrix is proposed. This eliminates the need for a cyclic solution of the Riccati equation; however, due to the simplifications adopted in the model, there is the undesired consequence of a non-zero steady-state error. Therefore, a nonlinear switching component is introduced into the control signal, to reduce the error to zero. In simulation tests, the proposed solution was evaluated against selected quantity indices. The paper ends with conclusions and observations.