Continuous Sliding Mode Control of a Quadrotor

TLDR: In this article, a sliding mode controller for stabilizing and trajectory tracking control of a quad-rotor helicopter using sliding mode controllers has been investigated, based on the definition of several terminal attractors to establish certain relationships between variables to be maintained.

Abstract: The interest into the unmanned aerial vehicles has largely increased recently. With the advances in technologies it has become possible to test efficiently and cost effectively different autonomous flight control concepts using small-scale aircrafts. In this work the stabilizing and trajectory tracking control problem of a quad-rotor helicopter using sliding mode controllers has been investigated. The well-known ability of the above control approach to stabilize under-actuated systems and to deal with existing nonlinear mismatched uncertainties in their dynamic models makes it a suitable choice for controlling rotorcrafts. The proposed method is based on the definition of several terminal attractors to establish certain relationships between variables to be maintained, thus allowing a designed continuous sliding mode controller to drive the system’s trajectory to a sliding surface in a finite time. Asymptotic stability of the system’s motion in the sliding mode is then achieved. The effectiveness of the adopted approach is demonstrated by the results from a simulated flight of an automatically controlled small-scale four-rotor helicopter.