The investigation of the work-fluid characteristics of precision hydraulic active vibration control module

Vibration control in the systems of precise positioning is an important problem that nanotechnology sector is facing. This problem challenges the engineers to develop advance positioning mechanisms such as hydraulic magnetorheological (MR) actuators or MR modules. These modules combine the characteristics of hydraulic systems and electromagnetic control because of the use of magnetorheological fluids instead of traditional hydraulic fluid. This allows to avoid using inertial valves that results in higher accuracy and dynamic characteristics as compared with conventional systems. The main element of a MR valve is a solenoid that creates a magnetic field to control viscosity and rheological behavior of the fluid due to structuring of the disperse phase of magnetic particles in magnetic field. The positioning error of the MR module depends, to great extent, on the minimum current which should be applied to the coil to start the motion. This work is aimed at the experimental study of the response of the MR module on the applied current. The response was measured as the pressure drop in the fluid at the exit of the MR module. It was found that the maximum magnetic field in the working gap of the module of 0.04 T corresponded to the pressure drop 0.12 MPa. The results form the base for design of MR modules of automatic control systems operating under semi- active and active vibration control modes. (C) 2017 The Authors. Published by Elsevier Ltd.