Passivity Based Control of Two Degrees of Freedom Twin Rotor Control System

This paper presents the passivity based control (PBC) design of a twin rotor helicopter model. Twin rotor system (TRS) is a two input two output nonlinear system. It consists of a vertical axle, on which a cylindrical joint connects a lever arm. It has two degrees of freedom, the azimuth and the vertical angle. Two rotors are mounted on the lever arm with the resultant aerodynamic forces giving rise to moments in both directions. There is a strong coupling between the movements about both the axes. The task is to control the attitude of the system. We design a feedback control law based on the energy shaping and damping injection (ESDI) technique and apply it to the twin rotor system. Our main contribution in this paper is the application of the technique to the system of this kind. Simulation results are shown to see the effectiveness of the approach.