Prescribed performance control for a pneumatic cylinder with strong friction via nonlinear extended state observer

In this paper, a nonlinear extended state observer (NESO)-based prescribed performance control (PPC) method is developed for a pneumatic cylinder with strong friction. For the system model, a pneumatic servo system with strong nonlinearity is established to describe the pneumatic cylinder with strong friction. To improve control accurate under the strong nonlinearity conditions, PPC is design to prescribe its transient and steady-state performances. Moreover, both the NESO convergence and the closed-loop system stability are analysed by utilising Lyapunov approaches. Finally, simulation results and experimental results confirm the effectiveness and robustness.