Robust Precision Motion Control for a Pneumatic Flexible Manipulator With Joint Coupling and Grasped Loads Based on a Nonlinear ESO and a Sliding Mode TD

In this paper, a motion control strategy is proposed for a pneumatic flexible manipulator with joint decoupling and a grasped load. A nonlinear extended state observer (ESO) is employed to estimate grasped load disturbances and joint coupling in the pneumatic flexible manipulator. An adaptive tornambe controller (TC) is proposed to provide further compensation and achieve robust precision motion control. A sliding mode tracking differentiator (TD) is designed to arrange a rapid transition process for the pneumatic flexible manipulator. Moreover, stability analyses of the sliding mode TD, the nonlinear ESO and the adaptive TC are conducted by Lyapunov methods. Experimental results are given to illustrate the feasibility of the proposed motion control strategy for the pneumatic flexible manipulator.