Robust Nonlinear Control of Missile Longitudinal Dynamics in Presence of Unmatched Uncertainty

In this paper, a robust control law is proposed, based on Lyapunov’s theory and sliding mode control theory, in order to track the angle of attack in nonlinear longitudinal dynamics of a missile. It is assumed that there are unmatched uncertainties in the nonlinear systems. In the proposed algorithm, the controller gains are optimized by Particle Swarm Optimization (PSO) algorithm. For this purpose, a cost function is extracted from the output tracking error. Simulation results show that the proposed algorithm has better performance than conventional Proportional-Integral-Derivative (PID) controller in the presence of unmatched uncertainties.