Missile Autopilot Design via Approximate Nonlinear Dynamic Inversion

Abstract

Input-output approximate linearisation of a non-linear fifth order system has been studied. A method for controlling the non-linear system that is i/o linearisable is examined that retains the order and the relative degree of the system in the linearisation process, hence producing a linearised system with no internal or zero dynamics. Desired tracking performance for lateral accelerations and roll rate of the missile is achieved by using a non-linear control law that has been derived by selecting the lateral velocities and roll rate as the linearisation outputs. Simulation results are shown that exercise the final design and show that the linearisation and controller design are satisfactory.