Parviz Alavi Tabrizi - Assistant Professor, Faculty of Mechanical Engineering, University of Tabriz
Mousa Rezaee - Assistant Professor, Faculty of Mechanical Engineering, University of Tabriz
Mehdi Hashemi - Graduate Student of Mechanical Engineering, Faculty of Mechanical Engineering, University of Tabriz

A combined adaptive control and pole placement approach for an electrohydraulic position tracking system is described. Nonlinear dynamic of the electrohydraulic servo system is obtained and linearized near the valve spool null position. The pole placement approach is used as the primary control system for the obtained linearized state space model of the position tracking system. There is wide variety of parametric uncertainties in the linearized model, so a model reference adaptive control system is applied to the resulted closed loop system as the complementary control system. The reference model which is selected by SQP optimization method is an ideal mathematical model which represents a desired response. This control approach is shown to be effective in the presence of disturbances and uncertainties by simulation.

Pole Placement, SQP Optimization, Adaptive Control, Lyapunov’s Direct Method