Applying fuzzy tuned PI control to a nonlinear hydraulic positioning system

Control of a nonlinear hydraulic positioning system which has been taken as an IFAC benchmark problem is studied in this paper. The robust control based on the linearised model was considered by Davison (1990). In this study we show that it is very difficult to design a controller based on the linearised model with the parameter uncertainties as given by Davison to achieve the required performance. However, it is possible to develop a simple fuzzy tuned PI controller based on the original nonlinear model given by Baumgartner (1977) to achieve a satisfactory performance.