A robust feedback linearization force control of a pneumatic actuator

In this paper, an implementation of a force control for a rodless pneumatic actuator is proposed. The increasing interest of pneumatic drives is due to numerous advantages as high degree of compliance and dexterity, force capabilities and ready availability of cheap air supply. We describe a feedback linearization technique applied on the analytical nonlinear structure, dependently affine on parameter uncertainties, that genetically characterizes the pneumatic plants. Farther parametric uncertainties and exogenous disturbances arise on the deduced linear structure, for which we require a multi-objective state-feedback control synthesis. The design objective is performed using a constrained H_∞ minimization that is compared to peak-to-peak gain performance. Additionally, in both cases, the optimization objective is applied under some closed-loop pole location constraints. A linear matrix inequality (LMI) based parametrization of both H_∞ and peak-to-peak gain suboptimal controllers is developed. And, experimental results are illustrated to validate the approach and to compare the performances.