A stable linear adaptive controller applied to a pneumatic actuator system

This paper presents a stable linear adaptive control scheme for the position control of a pneumatic actuator system. The proposed controller does not require the experimental identification of the mass flow rate, which is really a novelty in the field of such applications. The controller synthesis is based on an uncertain non-affine nonlinear model of the pneumatic system. Firstly, the existence of an ideal controller which can achieve position control objectives is demonstrated using the implicit function theory. Nevertheless, even if the actuator model is well-known, this ideal controller cannot be known and computed. The aim of the proposed approach is to construct this unknown ideal controller using a simple linear controller with a stable adaptation mechanism. The stability of the closed-loop system is studied by using a Lyapunov approach. Finally, simulation results are provided to show the capabilities of the presented control method.