Accurate Position Control for Hydraulic Servomechanisms

A common problem when operating heavy hydraulic machines consists in the inability of performing accurate motion. In the last few years the development of non-linear control techniques and the production of increasingly more accurate and cheaper hydraulic drives induced a steadily growing interest towards the development of controlled hydraulic systems. Clearly, this interest is also motivated by the possibility to exploit the huge power density, which is an intrinsic feature of hydraulic systems. This paper specifically focuses on the development of several position control schemes, whose aim is to guarantee accurate motion of a standalone hydraulic servomechanism. By relying on an experimentally validated mathematical model of the servomechanism itself, different control schemes have been synthesized and the resulting control performances have been verified and compared together.