Attitude control of a miniature helicopter using optimal sliding mode control

The problem of attitude stabilization of a small sized rotary wing unmanned aerial vehicle in the presence of input and parameters uncertainties is considered. For controller design, the sliding mode control (SMC) approach is employed. The SMC enforces the system trajectory to move towards a socalled sliding surface (manifold) in finite time, and remain on its vicinity thereafter using a high frequency switching signal, while approaching the equilibrium point. We choose a sliding surface which is optimal with respect to a quadratic performance index. The controller gains are tuned based on the upper bounds for the parameters and input uncertainties. Simulation results show the effective performance of the proposed controller.