Multivariable Super Twisting Based Robust Trajectory Tracking Control for Small Unmanned Helicopter

Abstract EN

This paper presents a highly robust trajectory tracking controller for small unmanned helicopter with model uncertainties and external disturbances.

First, a simplified dynamic model is developed, where the model uncertainties and external disturbances are treated as compounded disturbances.

Then the system is divided into three interconnected subsystems: altitude subsystem, yaw subsystem, and horizontal subsystem.

Second, a disturbance observer based controller (DOBC) is designed based upon backstepping and multivariable super twisting control algorithm to obtain robust trajectory tracking property.

A sliding mode observer works as an estimator of the compounded disturbances.

In order to lessen calculative burden, a first-order exact differentiator is employed to estimate the time derivative of the virtual control.

Moreover, proof of the stability of the closed-loop system based on Lyapunov method is given.

Finally, simulation results are presented to illustrate the effectiveness and robustness of the proposed flight control scheme.