Adaptive sliding mode control for quadrotor helicopters

This paper proposes an adaptive method based on sliding mode control for quadrotor helicopters. The flight control system of quadrotor helicopters is a typical nonlinear and uncertain system. Sliding mode control (SMC) is a robust method to control nonlinear and uncertain systems, and can keep the system insensitive to uncertainties on the sliding surface. However, its design requires the knowledge of the bound on the uncertainties, and sometimes it could be a hard task to estimate accurately the bound. The goal is to design an adaptive control law based on sliding mode control without the knowledge of uncertainties and perturbations bound. This adaptive methodology provides a minimum value of control gain K(t) resulting in minimization of the chattering effect. In order to adjust quickly the control gain K(t), the attenuation factor is introduced in the region of quasi sliding mode in this paper. Finally, Simulation results demonstrate the effectiveness of the proposed control method.