Abstract
This paper is concerned with robust controller design for hydraulic positioning systems. Generally, hydraulic positioning systems have problems such as large perturbation and input saturation. First, taking account of the large plant perturbation, we give a design method of feedback controllers via an LMI based H∞ loop shaping method, which reflects the current plant dynamics. Second, in order to cope with input saturation, we propose to adopt feedforward controllers which contain velocity limit function. Furthermore, the validity of the proposed design method is shown by experiments.