Sliding Mode Control Using Disturbance Observer for a Flexible Link Robot

This article focuses on the robust position tracking control of a two-degree-of-freedom serial flexible link (2DOFSFL) robot. With a disturbance observer (DO), the robust backstepping sliding mode controller which combines both the merits of the backstepping control and sliding mode control, is proposed to deal with the position tracking control problem of a 2DOFSFL robot in the presence of disturbances. The disturbance observer is employed to estimate the unknown disturbance which caused by DC motors and unknown external environment. The relevant experimental results are given to illustrate the effectiveness of the proposed control strategy for the position tracking of the 2DOFSFL robot system.