Position control for a two

In this paper, position control is addressed for a two-joint robot finger system driven by pneumatic artificial muscles. It is hard to obtain high precision control for a two-joint robot finger system due to coupling and nonlinearities. A two-input and two-output decoupling problem is solved via active disturbance rejection control without complicated calculations. An extended state observer is designed to estimate the nonlinearities. Furthermore, the stability of the two-joint robot finger system is shown by a back-stepping method. Results from experiments are demonstrated to show the effectiveness of the proposed control approach