Integral sliding mode altitude control for a small model helicopter with ground effect compensation

In this paper, a robust altitude control for small RC helicopters near ground surface is proposed. Stable takeoff, landing and hovering near surface are realized by both ground effect compensation and robust sliding mode control which suppresses the modeling error of dynamics and ground effect. To prevent the steady state error induced by the boundary layer which is indispensable to avoid chattering phenomena, integral sliding mode function is introduced which achieves asymptotic convergence to the desired altitude with continuous control input. We verified the robustness and effectiveness of the proposed control method through experiments of a RC small scale helicopter on hovering control near ground surface and external disturbance attenuation.