CACSD for hydraulic cylinders

Hydraulic drives such as synchronizing cylinders or differential cylinders have nonlinear plant dynamics. This paper demonstrates the advantage of using the computer algebra/symbolic computation system Maple to compute nonlinear controllers for the two different kind of plants treated here. Thus, we compute an exact linearizing controller for synchronizing cylinders with static state feedback using Maple. The controller shows good performance in experiments. Hydraulically driven differential cylinders, however, are not exact linearizable by static feedback with respect to the piston rod position as output. Thus, we design an input-output-linearizing controller for this kind of plant with the same software package. Again, this controller is tested in experiments and shows good performance