Adaptive Pole-Placement Control for Pneumatic Servo Systems.

In pneumatic servo systems, it is difficult to achieve high positioning accuracy using PID or optimal control methods, because the change in load mass and air compressibility causes parameter variation of the plant. In this paper, to enhance the positioning accuracy of pneumatic servo systems, we propose design scheme of the adaptive pole-placement control system. This plant consists of a pneumatic cylinder which is sealed by labyrinth packing, supported by air bearings and driven by two electro-pneumatic proportional valves. The Coulomb friction of the cylinder is negligible. Therefore, we consider only the influence of static friction. The feature of this design scheme is that an approximate integral compensator is introduced in order to eliminate the influence of constant disturbance caused by static friction