Control and stability analysis of an autonomous helicopter

This paper presents some results from the research on autonomous helicopter control conducted in the framework of the COMETS project. The paper presents both linear and non-linear control laws. A two-time scale decomposition of the helicopter dynamic has been used to analyse the dynamic behaviour of the system. The fast subsystem copes with the rotational dynamics, while the slow subsystem represents the translational dynamics. The stability of the fast dynamics is demonstrated by means of a Lyapunov function. Furthermore, a feedback linearization technique is proposed to stabilize the slow dynamics. Moreover, the drawbacks of the linear control laws are pointed out and a new nonlinear control law is proposed. This control law is able to control the helicopter when large variations occur in the orientation angles and position of the helicopter