Analysis and experimental validation of a pressure control method using magneto-rheology fluid flows

In this study, a spool actuating mechanism using controlled pressure difference is proposed for a large hydraulic servo valve. The actuating mechanism is accomplished by tuning magneto-rheological (MR) fluid flow. The relationship between the flow rate and the controlled chamber pressure is obtained based on a non-convex constitutive relation of the MR fluid. The control of the pressure difference by tuning the electrical flow is simulated. A series of experiments are carried out on a prototype system; the numerical and experimental results show that the proposed system can produce a very quick pressure change, which can be used to actuate the spool of the hydraulic servo valves for large flow rate applications.